System.Data.SQLite

<configuration>
  <system.data>
    <DbProviderFactories>
      <remove invariant="System.Data.SQLite"/>
      <add name="SQLite Data Provider" invariant="System.Data.SQLite" 
           description=".Net Framework Data Provider for SQLite"
           type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite,
                 Version=1.0.67.0, Culture=neutral,
                 PublicKeyToken=db937bc2d44ff139"/>
    </DbProviderFactories>
  </system.data>
</configuration>
</pre>
      </div>
      <p>

          </td>
        </tr>
      </table>
    </div>
    <div id="mainSection">
    <div id="mainBody">
    <h1 class="heading">Version History</h1>
    <p><b>1.0.67.0 - January 3, 2011</b></p>
    <ul>
      <li>Code merge with SQLite 3.7.4</li>
      <li>Continuing work on supporting Visual Studio 2010</li>
    </ul>
    <p><b>1.0.66.1 - August 1, 2010</b></p>
    <ul>
      <li>Code merge with SQLite 3.7.0.1</li>
      <li>Re-enabled VS2005 designer support, broken in previous versions during the 2008 transition</li>
      <li>Implemented new forms of Take/Skip in the EF framework courtesy jlsantiago</li>
      <li>Added "Foreign Keys" to the connection string parameters</li>
      <li>Added the Truncate option to the Journal Modes enumeration</li>
    </ul>
    <p><b>1.0.66.0 - April 18, 2010</b></p>
    <ul>
      <li>Code merge with SQLite 3.6.23.1</li>
      <li>Fixed a bug in the installer that accidentally modified the machine.config on .NET versions prior to 2.0, invaliding the config file.</li>
      <li>Fixed INTERSECT and EXCEPT union query generation in EF</li>
      <li>Fixed an out of memory error in the trigger designer in cases where a WHEN clause is used in the trigger</li>
    </ul>

using System;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.ConstrainedExecution;
using System.Resources;

// General Information about an assembly is controlled through the following 
// set of attributes. Change these attribute values to modify the information
// associated with an assembly.
[assembly: AssemblyTitle("SQLite.Designer")]
[assembly: AssemblyDescription("ADO.NET 4.0 Data Designer for SQLite")]
[assembly: AssemblyConfiguration("")]
[assembly: AssemblyCompany("http://sqlite.phxsoftware.com")]
[assembly: AssemblyProduct("SQLite Designer")]
[assembly: AssemblyCopyright("Public Domain")]
[assembly: AssemblyTrademark("")]
[assembly: AssemblyCulture("")]

//      Major Version
//      Minor Version 
//      Build Number
//      Revision
//
// You can specify all the values or you can default the Revision and Build Numbers 
// by using the '*' as shown below:
[assembly: AssemblyVersion("1.0.38.1")]
[assembly: AssemblyFileVersion("1.0.38.1")]
[assembly: AssemblyDelaySignAttribute(false)]
[assembly: AssemblyKeyFileAttribute("..\\System.Data.SQLite\\System.Data.SQLite.snk")]
[assembly: AssemblyKeyNameAttribute("")]

<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProductVersion>9.0.30729</ProductVersion>
    <SchemaVersion>2.0</SchemaVersion>
    <ProjectGuid>{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}</ProjectGuid>
    <OutputType>Library</OutputType>
    <AppDesignerFolder>Properties</AppDesignerFolder>
    <RootNamespace>SQLite.Designer</RootNamespace>
    <AssemblyName>SQLite.Designer</AssemblyName>
    <SignAssembly>false</SignAssembly>
    <RegisterOutputPackage>false</RegisterOutputPackage>
    <RegisterWithCodebase>false</RegisterWithCodebase>
    <GeneratePkgDefFile>false</GeneratePkgDefFile>
    <FileUpgradeFlags>
    </FileUpgradeFlags>
    <OldToolsVersion>3.5</OldToolsVersion>
    <UpgradeBackupLocation>
    </UpgradeBackupLocation>
    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
    <PublishUrl>publish\</PublishUrl>
    <Install>true</Install>
    <InstallFrom>Disk</InstallFrom>
    <UpdateEnabled>false</UpdateEnabled>
    <UpdateMode>Foreground</UpdateMode>
    <UpdateInterval>7</UpdateInterval>
    <UpdateIntervalUnits>Days</UpdateIntervalUnits>
    <UpdatePeriodically>false</UpdatePeriodically>
    <UpdateRequired>false</UpdateRequired>
    <MapFileExtensions>true</MapFileExtensions>
    <ApplicationRevision>0</ApplicationRevision>
    <ApplicationVersion>1.0.0.%2a</ApplicationVersion>
    <IsWebBootstrapper>false</IsWebBootstrapper>
    <UseApplicationTrust>false</UseApplicationTrust>
    <BootstrapperEnabled>true</BootstrapperEnabled>
    <TargetFrameworkProfile />
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>..\bin\designer\</OutputPath>
    <DefineConstants>DEBUG;TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
    <NoWarn>1701;1702;1699;3001</NoWarn>
    <FileAlignment>512</FileAlignment>
    <PlatformTarget>x86</PlatformTarget>
    <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
    <RegisterOutputPackage>false</RegisterOutputPackage>
    <GeneratePkgDefFile>false</GeneratePkgDefFile>
    <RegisterWithCodebase>false</RegisterWithCodebase>
    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>none</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>..\bin\Designer\</OutputPath>
    <DefineConstants>
    </DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
    <NoWarn>1701;1702;1699;3001</NoWarn>
    <FileAlignment>512</FileAlignment>
    <PlatformTarget>x86</PlatformTarget>
    <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
    <RegisterOutputPackage>false</RegisterOutputPackage>
    <RegisterWithCodebase>false</RegisterWithCodebase>
    <GeneratePkgDefFile>false</GeneratePkgDefFile>
    <UseVSHostingProcess>false</UseVSHostingProcess>
    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|x86'">
    <DebugSymbols>true</DebugSymbols>
    <OutputPath>bin\x86\Debug\</OutputPath>
    <DefineConstants>DEBUG;TRACE</DefineConstants>
    <NoWarn>1701;1702;1699;3001</NoWarn>
    <DebugType>full</DebugType>
    <PlatformTarget>x86</PlatformTarget>
    <CodeAnalysisLogFile>..\bin\designer\SQLite.Designer.dll.CodeAnalysisLog.xml</CodeAnalysisLogFile>
    <CodeAnalysisUseTypeNameInSuppression>true</CodeAnalysisUseTypeNameInSuppression>
    <CodeAnalysisModuleSuppressionsFile>GlobalSuppressions.cs</CodeAnalysisModuleSuppressionsFile>
    <ErrorReport>prompt</ErrorReport>
    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRuleSetDirectories>;C:\Program Files (x86)\Microsoft Visual Studio 10.0\Team Tools\Static Analysis Tools\\Rule Sets</CodeAnalysisRuleSetDirectories>
    <CodeAnalysisRuleDirectories>;C:\Program Files (x86)\Microsoft Visual Studio 10.0\Team Tools\Static Analysis Tools\FxCop\\Rules</CodeAnalysisRuleDirectories>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x86'">
    <OutputPath>..\bin\designer\</OutputPath>
    <Optimize>true</Optimize>
    <NoWarn>1701;1702;1699;3001</NoWarn>
    <PlatformTarget>x86</PlatformTarget>
    <CodeAnalysisLogFile>..\bin\Designer\SQLite.Designer.dll.CodeAnalysisLog.xml</CodeAnalysisLogFile>
    <CodeAnalysisUseTypeNameInSuppression>true</CodeAnalysisUseTypeNameInSuppression>
    <CodeAnalysisModuleSuppressionsFile>GlobalSuppressions.cs</CodeAnalysisModuleSuppressionsFile>
    <UseVSHostingProcess>false</UseVSHostingProcess>
    <ErrorReport>prompt</ErrorReport>
    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRuleSetDirectories>;C:\Program Files (x86)\Microsoft Visual Studio 10.0\Team Tools\Static Analysis Tools\\Rule Sets</CodeAnalysisRuleSetDirectories>
    <CodeAnalysisRuleDirectories>;C:\Program Files (x86)\Microsoft Visual Studio 10.0\Team Tools\Static Analysis Tools\FxCop\\Rules</CodeAnalysisRuleDirectories>
  </PropertyGroup>
  <ItemGroup>
    <Reference Include="EnvDTE, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>..\..\..\Program Files (x86)\Microsoft Visual Studio 9.0\Common7\IDE\PublicAssemblies\EnvDTE.dll</HintPath>
    </Reference>
    <Reference Include="Microsoft.Data.ConnectionUI, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>..\..\..\Program Files (x86)\Microsoft Visual Studio 2008 SDK\VisualStudioIntegration\Common\Assemblies\2005\Microsoft.Data.ConnectionUI.dll</HintPath>
      <Private>False</Private>
    </Reference>
    <Reference Include="Microsoft.VisualStudio.CommandBars, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>..\..\..\Program Files (x86)\Common Files\Microsoft Shared\MSEnv\PublicAssemblies\Microsoft.VisualStudio.CommandBars.dll</HintPath>
    </Reference>
    <Reference Include="Microsoft.VisualStudio.Data, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">

      <SpecificVersion>False</SpecificVersion>
      <HintPath>..\..\..\Program Files (x86)\Microsoft Visual Studio 2008 SDK\VisualStudioIntegration\Common\Assemblies\2005\Microsoft.VisualStudio.Data.dll</HintPath>
      <Private>False</Private>
    </Reference>
    <Reference Include="Microsoft.VisualStudio.Data.Services, Version=9.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL" />
    <Reference Include="Microsoft.VisualStudio.OLE.Interop, Version=7.1.40304.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">
      <SpecificVersion>False</SpecificVersion>
    </Reference>
    <Reference Include="Microsoft.VisualStudio.Shell, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
      <SpecificVersion>False</SpecificVersion>
    </Reference>
    <Reference Include="Microsoft.VisualStudio.Shell.Interop, Version=7.1.40304.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">

  <ItemGroup>
    <VSCTCompile Include="PkgCmd.vsct">
      <ResourceName>1000</ResourceName>
    </VSCTCompile>
  </ItemGroup>
  <ItemGroup>
    <EmbeddedResource Include="SQLiteDataViewSupport2008.xml" />
    <EmbeddedResource Include="SQLiteDataViewSupport2010.xml" />
    <EmbeddedResource Include="VSPackage.resx">
      <Generator>ResXFileCodeGenerator</Generator>
      <LastGenOutput>VSPackage.Designer.cs</LastGenOutput>
      <MergeWithCTO>true</MergeWithCTO>
      <SubType>Designer</SubType>
    </EmbeddedResource>
  </ItemGroup>

  </ItemGroup>
  <ItemGroup>
    <None Include="Resources\ToolboxItems.txt" />
  </ItemGroup>
  <ItemGroup>
    <Folder Include="Properties\" />
  </ItemGroup>
  <ItemGroup>
    <None Include="source.extension.vsixmanifest" />
  </ItemGroup>
  <ItemGroup>
    <BootstrapperPackage Include="Microsoft.Net.Client.3.5">
      <Visible>False</Visible>
      <ProductName>.NET Framework 3.5 SP1 Client Profile</ProductName>
      <Install>false</Install>
    </BootstrapperPackage>
    <BootstrapperPackage Include="Microsoft.Net.Framework.3.5.SP1">
      <Visible>False</Visible>
      <ProductName>.NET Framework 3.5 SP1</ProductName>
      <Install>true</Install>
    </BootstrapperPackage>
    <BootstrapperPackage Include="Microsoft.Windows.Installer.3.1">
      <Visible>False</Visible>
      <ProductName>Windows Installer 3.1</ProductName>
      <Install>true</Install>
    </BootstrapperPackage>
  </ItemGroup>
  <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
  <Import Project="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v10.0\VSSDK\Microsoft.VsSDK.targets" />
  <PropertyGroup>
    <PostBuildEvent>
    </PostBuildEvent>
  </PropertyGroup>
</Project>

Microsoft Visual Studio Solution File, Format Version 11.00
# Visual Studio 2010
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SQLite.Designer", "SQLite.Designer.csproj", "{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}"
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "install", "..\tools\install\install.csproj", "{71EED886-B5BF-488E-A4AA-1403E393D224}"
	ProjectSection(ProjectDependencies) = postProject

		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198} = {9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}
	EndProjectSection
EndProject


Global
	GlobalSection(SolutionConfigurationPlatforms) = preSolution
		Debug|Any CPU = Debug|Any CPU
		Debug|x86 = Debug|x86
		Release|Any CPU = Release|Any CPU
		Release|x86 = Release|x86
	EndGlobalSection
	GlobalSection(ProjectConfigurationPlatforms) = postSolution
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Debug|x86.ActiveCfg = Debug|x86
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Debug|x86.Build.0 = Debug|x86
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Release|Any CPU.ActiveCfg = Release|x86
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Release|Any CPU.Build.0 = Release|x86
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Release|x86.ActiveCfg = Release|x86
		{9B4A5CF6-5BE5-4926-ACC7-B729A8C05198}.Release|x86.Build.0 = Release|x86
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Debug|x86.ActiveCfg = Debug|x86
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Debug|x86.Build.0 = Debug|x86


		{71EED886-B5BF-488E-A4AA-1403E393D224}.Release|Any CPU.ActiveCfg = Release|Any CPU
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Release|Any CPU.Build.0 = Release|Any CPU
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Release|x86.ActiveCfg = Release|x86
		{71EED886-B5BF-488E-A4AA-1403E393D224}.Release|x86.Build.0 = Release|x86
	EndGlobalSection
	GlobalSection(SolutionProperties) = preSolution
		HideSolutionNode = FALSE
	EndGlobalSection
EndGlobal

    private static string GetVSVersion()
    {
      switch (System.Diagnostics.FileVersionInfo.GetVersionInfo(Environment.GetCommandLineArgs()[0]).FileMajorPart)
      {
        case 8:
          return "2005";
		case 10:
		  return "2010";
        default:
          return "2008";
      }
    }
  }
}

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version:4.0.30319.1
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace SQLite.Designer {
    using System;
    
    
    /// <summary>
    ///   A strongly-typed resource class, for looking up localized strings, etc.
    /// </summary>
    // This class was auto-generated by the StronglyTypedResourceBuilder
    // class via a tool like ResGen or Visual Studio.
    // To add or remove a member, edit your .ResX file then rerun ResGen
    // with the /str option, or rebuild your VS project.
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "4.0.0.0")]
    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
    internal class VSPackage {
        
        private static global::System.Resources.ResourceManager resourceMan;
        
        private static global::System.Globalization.CultureInfo resourceCulture;

        internal static string ReEncrypt {
            get {
                return ResourceManager.GetString("ReEncrypt", resourceCulture);
            }
        }
        
        /// <summary>
        ///   Looks up a localized string similar to [SQLite]
        ///System.Data.SQLite.SQLiteConnection, System.Data.SQLite
        ///System.Data.SQLite.SQLiteDataAdapter, System.Data.SQLite
        ///System.Data.SQLite.SQLiteCommand, System.Data.SQLite
        ///.
        /// </summary>
        internal static string ToolboxItems {
            get {
                return ResourceManager.GetString("ToolboxItems", resourceCulture);
            }
        }
    }
}

/* fts2 has a design flaw which can lead to database corruption (see
** below).  It is recommended not to use it any longer, instead use
** fts3 (or higher).  If you believe that your use of fts2 is safe,
** add -DSQLITE_ENABLE_BROKEN_FTS2=1 to your CFLAGS.
*/
#if (!defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS2)) \
        && !defined(SQLITE_ENABLE_BROKEN_FTS2)
#error fts2 has a design flaw and has been deprecated.
#endif
/* The flaw is that fts2 uses the content table's unaliased rowid as
** the unique docid.  fts2 embeds the rowid in the index it builds,
** and expects the rowid to not change.  The SQLite VACUUM operation
** will renumber such rowids, thereby breaking fts2.  If you are using
** fts2 in a system which has disabled VACUUM, then you can continue

**
** This appears to have only a moderate impact on queries for very
** frequent terms (which are somewhat dominated by segment merge
** costs), and infrequent and non-existent terms still seem to be fast
** even with many segments.
**
** TODO(shess) That said, it would be nice to have a better query-side
** argument for MERGE_COUNT of 16.  Also, it is possible/likely that
** optimizations to things like doclist merging will swing the sweet
** spot around.
**
**
**
**** Handling of deletions and updates ****
** Since we're using a segmented structure, with no docid-oriented

# define SQLITE_CORE 1
#endif

#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>


#include "fts2.h"
#include "fts2_hash.h"
#include "fts2_tokenizer.h"
#include "sqlite3.h"
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1

*/
/* TODO(shess) The snippet-generation code should be using the
** tokenizer-generated tokens rather than doing its own local
** tokenization.
*/
/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */
static int safe_isspace(char c){
  return c==' ' || c=='\t' || c=='\n' || c=='\r' || c=='\v' || c=='\f';
}
static int safe_tolower(char c){
  return (c>='A' && c<='Z') ? (c - 'A' + 'a') : c;
}
static int safe_isalnum(char c){
  return (c>='0' && c<='9') || (c>='A' && c<='Z') || (c>='a' && c<='z');
}

typedef enum DocListType {
  DL_DOCIDS,              /* docids only */
  DL_POSITIONS,           /* docids + positions */
  DL_POSITIONS_OFFSETS    /* docids + positions + offsets */
} DocListType;

/* DataBuffer is used to collect data into a buffer in piecemeal
** fashion.  It implements the usual distinction between amount of
** data currently stored (nData) and buffer capacity (nCapacity).
**
** dataBufferInit - create a buffer with given initial capacity.
** dataBufferReset - forget buffer's data, retaining capacity.
** dataBufferDestroy - free buffer's data.
** dataBufferSwap - swap contents of two buffers.
** dataBufferExpand - expand capacity without adding data.
** dataBufferAppend - append data.
** dataBufferAppend2 - append two pieces of data at once.
** dataBufferReplace - replace buffer's data.
*/
typedef struct DataBuffer {
  char *pData;          /* Pointer to malloc'ed buffer. */
  int nCapacity;        /* Size of pData buffer. */
  int nData;            /* End of data loaded into pData. */
} DataBuffer;

static void dataBufferInit(DataBuffer *pBuffer, int nCapacity){
  assert( nCapacity>=0 );
  pBuffer->nData = 0;
  pBuffer->nCapacity = nCapacity;
  pBuffer->pData = nCapacity==0 ? NULL : sqlite3_malloc(nCapacity);
}
static void dataBufferReset(DataBuffer *pBuffer){
  pBuffer->nData = 0;
}
static void dataBufferDestroy(DataBuffer *pBuffer){
  if( pBuffer->pData!=NULL ) sqlite3_free(pBuffer->pData);
  SCRAMBLE(pBuffer);
}
static void dataBufferSwap(DataBuffer *pBuffer1, DataBuffer *pBuffer2){
  DataBuffer tmp = *pBuffer1;
  *pBuffer1 = *pBuffer2;
  *pBuffer2 = tmp;
}
static void dataBufferExpand(DataBuffer *pBuffer, int nAddCapacity){
  assert( nAddCapacity>0 );
  /* TODO(shess) Consider expanding more aggressively.  Note that the
  ** underlying malloc implementation may take care of such things for
  ** us already.
  */
  if( pBuffer->nData+nAddCapacity>pBuffer->nCapacity ){
    pBuffer->nCapacity = pBuffer->nData+nAddCapacity;
    pBuffer->pData = sqlite3_realloc(pBuffer->pData, pBuffer->nCapacity);
  }
}
static void dataBufferAppend(DataBuffer *pBuffer,
                             const char *pSource, int nSource){
  assert( nSource>0 && pSource!=NULL );
  dataBufferExpand(pBuffer, nSource);
  memcpy(pBuffer->pData+pBuffer->nData, pSource, nSource);

}
static void dlrDestroy(DLReader *pReader){
  SCRAMBLE(pReader);
}

#ifndef NDEBUG
/* Verify that the doclist can be validly decoded.  Also returns the
** last docid found because it is convenient in other assertions for
** DLWriter.
*/
static void docListValidate(DocListType iType, const char *pData, int nData,
                            sqlite_int64 *pLastDocid){
  sqlite_int64 iPrevDocid = 0;
  assert( nData>0 );
  assert( pData!=0 );

  DLWriter dlw;
  PLWriter plw;
} DLCollector;

/* TODO(shess) This could also be done by calling plwTerminate() and
** dataBufferAppend().  I tried that, expecting nominal performance
** differences, but it seemed to pretty reliably be worth 1% to code
** it this way.  I suspect it is the incremental malloc overhead (some
** percentage of the plwTerminate() calls will cause a realloc), so
** this might be worth revisiting if the DataBuffer implementation
** changes.
*/
static void dlcAddDoclist(DLCollector *pCollector, DataBuffer *b){
  if( pCollector->dlw.iType>DL_DOCIDS ){
    char c[VARINT_MAX];

}
static void dlcAddPos(DLCollector *pCollector, int iColumn, int iPos,
                      int iStartOffset, int iEndOffset){
  plwAdd(&pCollector->plw, iColumn, iPos, iStartOffset, iEndOffset);
}

static DLCollector *dlcNew(sqlite_int64 iDocid, DocListType iType){
  DLCollector *pCollector = sqlite3_malloc(sizeof(DLCollector));
  dataBufferInit(&pCollector->b, 0);
  dlwInit(&pCollector->dlw, iType, &pCollector->b);
  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
  return pCollector;
}
static void dlcDelete(DLCollector *pCollector){
  plwDestroy(&pCollector->plw);
  dlwDestroy(&pCollector->dlw);
  dataBufferDestroy(&pCollector->b);
  SCRAMBLE(pCollector);
  sqlite3_free(pCollector);
}


/* Copy the doclist data of iType in pData/nData into *out, trimming
** unnecessary data as we go.  Only columns matching iColumn are
** copied, all columns copied if iColumn is -1.  Elements with no
** matching columns are dropped.  The output is an iOutType doclist.

  const char *pRight, int nRight,
  DataBuffer *pOut      /* Write the combined doclist here */
){
  DLReader left, right;
  DLWriter writer;

  if( nLeft==0 ){
    if( nRight!=0) dataBufferAppend(pOut, pRight, nRight);
    return;
  }
  if( nRight==0 ){
    dataBufferAppend(pOut, pLeft, nLeft);
    return;
  }

  const char *pRight, int nRight,
  DataBuffer *pOut      /* Write the combined doclist here */
){
  DLReader left, right;
  DLWriter writer;

  if( nLeft==0 ){
    if( nRight!=0 ) dataBufferAppend(pOut, pRight, nRight);
    return;
  }
  if( nRight==0 ){
    dataBufferAppend(pOut, pLeft, nLeft);
    return;
  }

  dlrDestroy(&left);
  dlrDestroy(&right);
  dlwDestroy(&writer);
}

static char *string_dup_n(const char *s, int n){
  char *str = sqlite3_malloc(n + 1);
  memcpy(str, s, n);
  str[n] = '\0';
  return str;
}

/* Duplicate a string; the caller must free() the returned string.
 * (We don't use strdup() since it is not part of the standard C library and
 * may not be available everywhere.) */
static char *string_dup(const char *s){
  return string_dup_n(s, strlen(s));
}

/* Format a string, replacing each occurrence of the % character with
 * zDb.zName.  This may be more convenient than sqlite_mprintf()

  /* first compute length needed */
  for(p = zFormat ; *p ; ++p){
    len += (*p=='%' ? nFullTableName : 1);
  }
  len += 1;  /* for null terminator */

  r = result = sqlite3_malloc(len);
  for(p = zFormat; *p; ++p){
    if( *p=='%' ){
      memcpy(r, zDb, nDb);
      r += nDb;
      *r++ = '.';
      memcpy(r, zName, nName);
      r += nName;

static int sql_exec(sqlite3 *db, const char *zDb, const char *zName,
                    const char *zFormat){
  char *zCommand = string_format(zFormat, zDb, zName);
  int rc;
  TRACE(("FTS2 sql: %s\n", zCommand));
  rc = sqlite3_exec(db, zCommand, NULL, 0, NULL);
  sqlite3_free(zCommand);
  return rc;
}

static int sql_prepare(sqlite3 *db, const char *zDb, const char *zName,
                       sqlite3_stmt **ppStmt, const char *zFormat){
  char *zCommand = string_format(zFormat, zDb, zName);
  int rc;
  TRACE(("FTS2 prepare: %s\n", zCommand));
  rc = sqlite3_prepare_v2(db, zCommand, -1, ppStmt, NULL);
  sqlite3_free(zCommand);
  return rc;
}

/* end utility functions */

/* Forward reference */
typedef struct fulltext_vtab fulltext_vtab;

} QueryType;

typedef enum fulltext_statement {
  CONTENT_INSERT_STMT,
  CONTENT_SELECT_STMT,
  CONTENT_UPDATE_STMT,
  CONTENT_DELETE_STMT,
  CONTENT_EXISTS_STMT,

  BLOCK_INSERT_STMT,
  BLOCK_SELECT_STMT,
  BLOCK_DELETE_STMT,
  BLOCK_DELETE_ALL_STMT,

  SEGDIR_MAX_INDEX_STMT,
  SEGDIR_SET_STMT,
  SEGDIR_SELECT_LEVEL_STMT,
  SEGDIR_SPAN_STMT,
  SEGDIR_DELETE_STMT,
  SEGDIR_SELECT_SEGMENT_STMT,
  SEGDIR_SELECT_ALL_STMT,
  SEGDIR_DELETE_ALL_STMT,
  SEGDIR_COUNT_STMT,

  MAX_STMT                     /* Always at end! */
} fulltext_statement;

/* These must exactly match the enum above. */
/* TODO(shess): Is there some risk that a statement will be used in two
** cursors at once, e.g.  if a query joins a virtual table to itself?
** If so perhaps we should move some of these to the cursor object.
*/
static const char *const fulltext_zStatement[MAX_STMT] = {
  /* CONTENT_INSERT */ NULL,  /* generated in contentInsertStatement() */
  /* CONTENT_SELECT */ "select * from %_content where rowid = ?",
  /* CONTENT_UPDATE */ NULL,  /* generated in contentUpdateStatement() */
  /* CONTENT_DELETE */ "delete from %_content where rowid = ?",
  /* CONTENT_EXISTS */ "select rowid from %_content limit 1",

  /* BLOCK_INSERT */ "insert into %_segments values (?)",
  /* BLOCK_SELECT */ "select block from %_segments where rowid = ?",
  /* BLOCK_DELETE */ "delete from %_segments where rowid between ? and ?",
  /* BLOCK_DELETE_ALL */ "delete from %_segments",

  /* SEGDIR_MAX_INDEX */ "select max(idx) from %_segdir where level = ?",
  /* SEGDIR_SET */ "insert into %_segdir values (?, ?, ?, ?, ?, ?)",
  /* SEGDIR_SELECT_LEVEL */
  "select start_block, leaves_end_block, root from %_segdir "
  " where level = ? order by idx",
  /* SEGDIR_SPAN */
  "select min(start_block), max(end_block) from %_segdir "
  " where level = ? and start_block <> 0",
  /* SEGDIR_DELETE */ "delete from %_segdir where level = ?",

  /* NOTE(shess): The first three results of the following two
  ** statements must match.
  */
  /* SEGDIR_SELECT_SEGMENT */
  "select start_block, leaves_end_block, root from %_segdir "
  " where level = ? and idx = ?",
  /* SEGDIR_SELECT_ALL */
  "select start_block, leaves_end_block, root from %_segdir "
  " order by level desc, idx asc",
  /* SEGDIR_DELETE_ALL */ "delete from %_segdir",
  /* SEGDIR_COUNT */ "select count(*), ifnull(max(level),0) from %_segdir",
};

/*
** A connection to a fulltext index is an instance of the following
** structure.  The xCreate and xConnect methods create an instance
** of this structure and xDestroy and xDisconnect free that instance.
** All other methods receive a pointer to the structure as one of their

      case CONTENT_UPDATE_STMT:
        zStmt = contentUpdateStatement(v); break;
      default:
        zStmt = fulltext_zStatement[iStmt];
    }
    rc = sql_prepare(v->db, v->zDb, v->zName, &v->pFulltextStatements[iStmt],
                         zStmt);
    if( zStmt != fulltext_zStatement[iStmt]) sqlite3_free((void *) zStmt);
    if( rc!=SQLITE_OK ) return rc;
  } else {
    int rc = sqlite3_reset(v->pFulltextStatements[iStmt]);
    if( rc!=SQLITE_OK ) return rc;
  }

  *ppStmt = v->pFulltextStatements[iStmt];
  return SQLITE_OK;
}

/* Like sqlite3_step(), but convert SQLITE_DONE to SQLITE_OK and
** SQLITE_ROW to SQLITE_ERROR.  Useful for statements like UPDATE,
** where we expect no results.
*/
static int sql_single_step(sqlite3_stmt *s){
  int rc = sqlite3_step(s);
  return (rc==SQLITE_DONE) ? SQLITE_OK : rc;
}

/* Like sql_get_statement(), but for special replicated LEAF_SELECT
** statements.  idx -1 is a special case for an uncached version of
** the statement (used in the optimize implementation).
*/
/* TODO(shess) Write version for generic statements and then share
** that between the cached-statement functions.
*/
static int sql_get_leaf_statement(fulltext_vtab *v, int idx,
                                  sqlite3_stmt **ppStmt){
  assert( idx>=-1 && idx<MERGE_COUNT );
  if( idx==-1 ){
    return sql_prepare(v->db, v->zDb, v->zName, ppStmt, LEAF_SELECT);
  }else if( v->pLeafSelectStmts[idx]==NULL ){
    int rc = sql_prepare(v->db, v->zDb, v->zName, &v->pLeafSelectStmts[idx],
                         LEAF_SELECT);
    if( rc!=SQLITE_OK ) return rc;
  }else{
    int rc = sqlite3_reset(v->pLeafSelectStmts[idx]);
    if( rc!=SQLITE_OK ) return rc;
  }

  return sql_single_step(s);
}

static void freeStringArray(int nString, const char **pString){
  int i;

  for (i=0 ; i < nString ; ++i) {
    if( pString[i]!=NULL ) sqlite3_free((void *) pString[i]);
  }
  sqlite3_free((void *) pString);
}

/* select * from %_content where rowid = [iRow]
 * The caller must delete the returned array and all strings in it.
 * null fields will be NULL in the returned array.
 *
 * TODO: Perhaps we should return pointer/length strings here for consistency

  rc = sqlite3_bind_int64(s, 1, iRow);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3_step(s);
  if( rc!=SQLITE_ROW ) return rc;

  values = (const char **) sqlite3_malloc(v->nColumn * sizeof(const char *));
  for(i=0; i<v->nColumn; ++i){
    if( sqlite3_column_type(s, i)==SQLITE_NULL ){
      values[i] = NULL;
    }else{
      values[i] = string_dup((char*)sqlite3_column_text(s, i));
    }
  }

  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3_bind_int64(s, 1, iRow);
  if( rc!=SQLITE_OK ) return rc;

  return sql_single_step(s);
}

/* Returns SQLITE_ROW if any rows exist in %_content, SQLITE_DONE if
** no rows exist, and any error in case of failure.
*/
static int content_exists(fulltext_vtab *v){
  sqlite3_stmt *s;
  int rc = sql_get_statement(v, CONTENT_EXISTS_STMT, &s);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3_step(s);
  if( rc!=SQLITE_ROW ) return rc;

  /* We expect only one row.  We must execute another sqlite3_step()
   * to complete the iteration; otherwise the table will remain locked. */
  rc = sqlite3_step(s);
  if( rc==SQLITE_DONE ) return SQLITE_ROW;
  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
  return rc;
}

/* insert into %_segments values ([pData])
**   returns assigned rowid in *piBlockid
*/
static int block_insert(fulltext_vtab *v, const char *pData, int nData,
                        sqlite_int64 *piBlockid){
  sqlite3_stmt *s;

  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3_bind_int64(s, 1, iLevel);
  if( rc!=SQLITE_OK ) return rc;

  return sql_single_step(s);
}

/* Delete entire fts index, SQLITE_OK on success, relevant error on
** failure.
*/
static int segdir_delete_all(fulltext_vtab *v){
  sqlite3_stmt *s;
  int rc = sql_get_statement(v, SEGDIR_DELETE_ALL_STMT, &s);
  if( rc!=SQLITE_OK ) return rc;

  rc = sql_single_step(s);
  if( rc!=SQLITE_OK ) return rc;

  rc = sql_get_statement(v, BLOCK_DELETE_ALL_STMT, &s);
  if( rc!=SQLITE_OK ) return rc;

  return sql_single_step(s);
}

/* Returns SQLITE_OK with *pnSegments set to the number of entries in
** %_segdir and *piMaxLevel set to the highest level which has a
** segment.  Otherwise returns the SQLite error which caused failure.
*/
static int segdir_count(fulltext_vtab *v, int *pnSegments, int *piMaxLevel){
  sqlite3_stmt *s;
  int rc = sql_get_statement(v, SEGDIR_COUNT_STMT, &s);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3_step(s);
  /* TODO(shess): This case should not be possible?  Should stronger
  ** measures be taken if it happens?
  */
  if( rc==SQLITE_DONE ){
    *pnSegments = 0;
    *piMaxLevel = 0;
    return SQLITE_OK;
  }
  if( rc!=SQLITE_ROW ) return rc;

  *pnSegments = sqlite3_column_int(s, 0);
  *piMaxLevel = sqlite3_column_int(s, 1);

  /* We expect only one row.  We must execute another sqlite3_step()
   * to complete the iteration; otherwise the table will remain locked. */
  rc = sqlite3_step(s);
  if( rc==SQLITE_DONE ) return SQLITE_OK;
  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
  return rc;
}

/* TODO(shess) clearPendingTerms() is far down the file because
** writeZeroSegment() is far down the file because LeafWriter is far
** down the file.  Consider refactoring the code to move the non-vtab
** code above the vtab code so that we don't need this forward
** reference.
*/

  if( v->pTokenizer!=NULL ){
    v->pTokenizer->pModule->xDestroy(v->pTokenizer);
    v->pTokenizer = NULL;
  }

  clearPendingTerms(v);

  sqlite3_free(v->azColumn);
  for(i = 0; i < v->nColumn; ++i) {
    sqlite3_free(v->azContentColumn[i]);
  }
  sqlite3_free(v->azContentColumn);
  sqlite3_free(v);
}

/*
** Token types for parsing the arguments to xConnect or xCreate.
*/
#define TOKEN_EOF         0    /* End of file */
#define TOKEN_SPACE       1    /* Any kind of whitespace */

** Space to hold the returned array is obtained from a single
** malloc and should be freed by passing the return value to free().
** The individual strings within the token list are all a part of
** the single memory allocation and will all be freed at once.
*/
static char **tokenizeString(const char *z, int *pnToken){
  int nToken = 0;
  Token *aToken = sqlite3_malloc( strlen(z) * sizeof(aToken[0]) );
  int n = 1;
  int e, i;
  int totalSize = 0;
  char **azToken;
  char *zCopy;
  while( n>0 ){
    n = getToken(z, &e);
    if( e!=TOKEN_SPACE ){
      aToken[nToken].z = z;
      aToken[nToken].n = n;
      nToken++;
      totalSize += n+1;
    }
    z += n;
  }
  azToken = (char**)sqlite3_malloc( nToken*sizeof(char*) + totalSize );
  zCopy = (char*)&azToken[nToken];
  nToken--;
  for(i=0; i<nToken; i++){
    azToken[i] = zCopy;
    n = aToken[i].n;
    memcpy(zCopy, aToken[i].z, n);
    zCopy[n] = 0;
    zCopy += n+1;
  }
  azToken[nToken] = 0;
  sqlite3_free(aToken);
  *pnToken = nToken;
  return azToken;
}

/*
** Convert an SQL-style quoted string into a normal string by removing
** the quote characters.  The conversion is done in-place.  If the

  char **azTokenizer;      /* Name of tokenizer and its arguments */
} TableSpec;

/*
** Reclaim all of the memory used by a TableSpec
*/
static void clearTableSpec(TableSpec *p) {
  sqlite3_free(p->azColumn);
  sqlite3_free(p->azContentColumn);
  sqlite3_free(p->azTokenizer);
}

/* Parse a CREATE VIRTUAL TABLE statement, which looks like this:
 *
 * CREATE VIRTUAL TABLE email
 *        USING fts2(subject, body, tokenize mytokenizer(myarg))
 *

  ** The argv[][] array is read-only and transient.  We can write to the
  ** copy in order to modify things and the copy is persistent.
  */
  CLEAR(pSpec);
  for(i=n=0; i<argc; i++){
    n += strlen(argv[i]) + 1;
  }
  azArg = sqlite3_malloc( sizeof(char*)*argc + n );
  if( azArg==0 ){
    return SQLITE_NOMEM;
  }
  z = (char*)&azArg[argc];
  for(i=0; i<argc; i++){
    azArg[i] = z;
    strcpy(z, argv[i]);

  ** converted to "_".  The cNN prefix guarantees that all column
  ** names are unique.
  **
  ** The AAAA suffix is not strictly necessary.  It is included
  ** for the convenience of people who might examine the generated
  ** %_content table and wonder what the columns are used for.
  */
  pSpec->azContentColumn = sqlite3_malloc( pSpec->nColumn * sizeof(char *) );
  if( pSpec->azContentColumn==0 ){
    clearTableSpec(pSpec);
    return SQLITE_NOMEM;
  }
  for(i=0; i<pSpec->nColumn; i++){
    char *p;
    pSpec->azContentColumn[i] = sqlite3_mprintf("c%d%s", i, azArg[i]);

  fulltext_vtab *v = 0;
  const sqlite3_tokenizer_module *m = NULL;
  char *schema;

  char const *zTok;         /* Name of tokenizer to use for this fts table */
  int nTok;                 /* Length of zTok, including nul terminator */

  v = (fulltext_vtab *) sqlite3_malloc(sizeof(fulltext_vtab));
  if( v==0 ) return SQLITE_NOMEM;
  CLEAR(v);
  /* sqlite will initialize v->base */
  v->db = db;
  v->zDb = spec->zDb;       /* Freed when azColumn is freed */
  v->zName = spec->zName;   /* Freed when azColumn is freed */
  v->nColumn = spec->nColumn;

  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
  return SQLITE_OK;
}

static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  fulltext_cursor *c;

  c = (fulltext_cursor *) sqlite3_malloc(sizeof(fulltext_cursor));
  if( c ){
    memset(c, 0, sizeof(fulltext_cursor));
    /* sqlite will initialize c->base */
    *ppCursor = &c->base;
    TRACE(("FTS2 Open %p: %p\n", pVTab, c));
    return SQLITE_OK;
  }else{
    return SQLITE_NOMEM;
  }
}


/* Free all of the dynamically allocated memory held by *q
*/
static void queryClear(Query *q){
  int i;
  for(i = 0; i < q->nTerms; ++i){
    sqlite3_free(q->pTerms[i].pTerm);
  }
  sqlite3_free(q->pTerms);
  CLEAR(q);
}

/* Free all of the dynamically allocated memory held by the
** Snippet
*/
static void snippetClear(Snippet *p){
  sqlite3_free(p->aMatch);
  sqlite3_free(p->zOffset);
  sqlite3_free(p->zSnippet);
  CLEAR(p);
}
/*
** Append a single entry to the p->aMatch[] log.
*/
static void snippetAppendMatch(
  Snippet *p,               /* Append the entry to this snippet */
  int iCol, int iTerm,      /* The column and query term */
  int iStart, int nByte     /* Offset and size of the match */
){
  int i;
  struct snippetMatch *pMatch;
  if( p->nMatch+1>=p->nAlloc ){
    p->nAlloc = p->nAlloc*2 + 10;
    p->aMatch = sqlite3_realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) );
    if( p->aMatch==0 ){
      p->nMatch = 0;
      p->nAlloc = 0;
      return;
    }
  }
  i = p->nMatch++;

  StringBuffer sb;
  char zBuf[200];
  if( p->zOffset ) return;
  initStringBuffer(&sb);
  for(i=0; i<p->nMatch; i++){
    struct snippetMatch *pMatch = &p->aMatch[i];
    zBuf[0] = ' ';
    sqlite3_snprintf(sizeof(zBuf)-1, &zBuf[cnt>0], "%d %d %d %d",
        pMatch->iCol, pMatch->iTerm, pMatch->iStart, pMatch->nByte);
    append(&sb, zBuf);
    cnt++;
  }
  p->zOffset = stringBufferData(&sb);
  p->nOffset = stringBufferLength(&sb);
}

  int nDoc;
  const char *zDoc;
  int iStart, iEnd;
  int tailEllipsis = 0;
  int iMatch;
  

  sqlite3_free(pCursor->snippet.zSnippet);
  pCursor->snippet.zSnippet = 0;
  aMatch = pCursor->snippet.aMatch;
  nMatch = pCursor->snippet.nMatch;
  initStringBuffer(&sb);

  for(i=0; i<nMatch; i++){
    aMatch[i].snStatus = SNIPPET_IGNORE;

  fulltext_cursor *c = (fulltext_cursor *) pCursor;
  TRACE(("FTS2 Close %p\n", c));
  sqlite3_finalize(c->pStmt);
  queryClear(&c->q);
  snippetClear(&c->snippet);
  if( c->result.nData!=0 ) dlrDestroy(&c->reader);
  dataBufferDestroy(&c->result);
  sqlite3_free(c);
  return SQLITE_OK;
}

static int fulltextNext(sqlite3_vtab_cursor *pCursor){
  fulltext_cursor *c = (fulltext_cursor *) pCursor;
  int rc;

}

/* Add a new term pTerm[0..nTerm-1] to the query *q.
*/
static void queryAdd(Query *q, const char *pTerm, int nTerm){
  QueryTerm *t;
  ++q->nTerms;
  q->pTerms = sqlite3_realloc(q->pTerms, q->nTerms * sizeof(q->pTerms[0]));
  if( q->pTerms==0 ){
    q->nTerms = 0;
    return;
  }
  t = &q->pTerms[q->nTerms - 1];
  CLEAR(t);
  t->pTerm = sqlite3_malloc(nTerm+1);
  memcpy(t->pTerm, pTerm, nTerm);
  t->pTerm[nTerm] = 0;
  t->nTerm = nTerm;
  t->isOr = q->nextIsOr;
  t->isPrefix = 0;
  q->nextIsOr = 0;
  t->iColumn = q->nextColumn;

  sqlite3_vtab_cursor *pCursor,     /* The cursor used for this query */
  int idxNum, const char *idxStr,   /* Which indexing scheme to use */
  int argc, sqlite3_value **argv    /* Arguments for the indexing scheme */
){
  fulltext_cursor *c = (fulltext_cursor *) pCursor;
  fulltext_vtab *v = cursor_vtab(c);
  int rc;


  TRACE(("FTS2 Filter %p\n",pCursor));

  /* If the cursor has a statement that was not prepared according to
  ** idxNum, clear it.  I believe all calls to fulltextFilter with a
  ** given cursor will have the same idxNum , but in this case it's
  ** easy to be safe.
  */
  if( c->pStmt && c->iCursorType!=idxNum ){
    sqlite3_finalize(c->pStmt);
    c->pStmt = NULL;
  }

  /* Get a fresh statement appropriate to idxNum. */
  /* TODO(shess): Add a prepared-statement cache in the vt structure.
  ** The cache must handle multiple open cursors.  Easier to cache the
  ** statement variants at the vt to reduce malloc/realloc/free here.
  ** Or we could have a StringBuffer variant which allowed stack
  ** construction for small values.
  */
  if( !c->pStmt ){
    char *zSql = sqlite3_mprintf("select rowid, * from %%_content %s",
                                 idxNum==QUERY_GENERIC ? "" : "where rowid=?");

    rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt, zSql);
    sqlite3_free(zSql);
    if( rc!=SQLITE_OK ) return rc;
    c->iCursorType = idxNum;
  }else{
    sqlite3_reset(c->pStmt);
    assert( c->iCursorType==idxNum );
  }

  switch( idxNum ){
    case QUERY_GENERIC:
      break;

    case QUERY_ROWID:
      rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0]));
      if( rc!=SQLITE_OK ) return rc;

  int iStartOffset, iEndOffset, iPosition;
  int rc;

  rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor);
  if( rc!=SQLITE_OK ) return rc;

  pCursor->pTokenizer = pTokenizer;
  while( SQLITE_OK==(rc=pTokenizer->pModule->xNext(pCursor,
                                                   &pToken, &nTokenBytes,
                                                   &iStartOffset, &iEndOffset,
                                                   &iPosition)) ){
    DLCollector *p;
    int nData;                   /* Size of doclist before our update. */

    /* Positions can't be negative; we use -1 as a terminator
     * internally.  Token can't be NULL or empty. */
    if( iPosition<0 || pToken == NULL || nTokenBytes == 0 ){

      rc = SQLITE_ERROR;
      break;
    }

    p = fts2HashFind(&v->pendingTerms, pToken, nTokenBytes);
    if( p==NULL ){
      nData = 0;
      p = dlcNew(iDocid, DL_DEFAULT);
      fts2HashInsert(&v->pendingTerms, pToken, nTokenBytes, p);

  /* TODO(shess) Check return?  Should this be able to cause errors at
  ** this point?  Actually, same question about sqlite3_finalize(),
  ** though one could argue that failure there means that the data is
  ** not durable.  *ponder*
  */
  pTokenizer->pModule->xClose(pCursor);
  if( SQLITE_DONE == rc ) return SQLITE_OK;
  return rc;
}

/* Add doclists for all terms in [pValues] to pendingTerms table. */
static int insertTerms(fulltext_vtab *v, sqlite_int64 iRowid,
                       sqlite3_value **pValues){
  int i;

  DataBuffer term;           /* Leftmost term in block's subtree. */
  DataBuffer data;           /* Accumulated data for the block. */
  struct InteriorBlock *next;
} InteriorBlock;

static InteriorBlock *interiorBlockNew(int iHeight, sqlite_int64 iChildBlock,
                                       const char *pTerm, int nTerm){
  InteriorBlock *block = sqlite3_malloc(sizeof(InteriorBlock));
  char c[VARINT_MAX+VARINT_MAX];
  int n;

  if( block ){
    memset(block, 0, sizeof(*block));
    dataBufferInit(&block->term, 0);
    dataBufferReplace(&block->term, pTerm, nTerm);

    n = putVarint(c, iHeight);
    n += putVarint(c+n, iChildBlock);
    dataBufferInit(&block->data, INTERIOR_MAX);
    dataBufferReplace(&block->data, c, n);
  }
  return block;
}

#ifndef NDEBUG
/* Verify that the data is readable as an interior node. */
static void interiorBlockValidate(InteriorBlock *pBlock){
  const char *pData = pBlock->data.pData;

  InteriorBlock *block = pWriter->first;

  while( block!=NULL ){
    InteriorBlock *b = block;
    block = block->next;
    dataBufferDestroy(&b->term);
    dataBufferDestroy(&b->data);
    sqlite3_free(b);
  }
  if( pWriter->parentWriter!=NULL ){
    interiorWriterDestroy(pWriter->parentWriter);
    sqlite3_free(pWriter->parentWriter);
  }
  dataBufferDestroy(&pWriter->term);
  SCRAMBLE(pWriter);
  return SQLITE_OK;
}

/* If pWriter can fit entirely in ROOT_MAX, return it as the root info

  ** interior node.
  */
  ASSERT_VALID_INTERIOR_BLOCK(block);
  rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
  if( rc!=SQLITE_OK ) return rc;
  *piEndBlockid = iBlockid;

  pWriter->parentWriter = sqlite3_malloc(sizeof(*pWriter->parentWriter));
  interiorWriterInit(pWriter->iHeight+1,
                     block->term.pData, block->term.nData,
                     iBlockid, pWriter->parentWriter);

  /* Flush additional blocks and append to the higher interior
  ** node.
  */

** this case.  Probably a brittle assumption.
*/
static int leavesReaderReset(LeavesReader *pReader){
  return sqlite3_reset(pReader->pStmt);
}

static void leavesReaderDestroy(LeavesReader *pReader){
  /* If idx is -1, that means we're using a non-cached statement
  ** handle in the optimize() case, so we need to release it.
  */
  if( pReader->pStmt!=NULL && pReader->idx==-1 ){
    sqlite3_finalize(pReader->pStmt);
  }
  leafReaderDestroy(&pReader->leafReader);
  dataBufferDestroy(&pReader->rootData);
  SCRAMBLE(pReader);
}

/* Initialize pReader with the given root data (if iStartBlockid==0
** the leaf data was entirely contained in the root), or from the

/* Initializes pReaders with the segments from level iLevel, returning
** the number of segments in *piReaders.  Leaves pReaders in sorted
** order.
*/
static int leavesReadersInit(fulltext_vtab *v, int iLevel,
                             LeavesReader *pReaders, int *piReaders){
  sqlite3_stmt *s;
  int i, rc = sql_get_statement(v, SEGDIR_SELECT_LEVEL_STMT, &s);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3_bind_int(s, 1, iLevel);
  if( rc!=SQLITE_OK ) return rc;

  i = 0;
  while( (rc = sqlite3_step(s))==SQLITE_ROW ){

 err:
  for(i=0; i<MERGE_COUNT; i++){
    leavesReaderDestroy(&lrs[i]);
  }
  leafWriterDestroy(&writer);
  return rc;
}

/* Accumulate the union of *acc and *pData into *acc. */
static void docListAccumulateUnion(DataBuffer *acc,
                                   const char *pData, int nData) {
  DataBuffer tmp = *acc;
  dataBufferInit(acc, tmp.nData+nData);
  docListUnion(tmp.pData, tmp.nData, pData, nData, acc);
  dataBufferDestroy(&tmp);
}

/* TODO(shess) It might be interesting to explore different merge
** strategies, here.  For instance, since this is a sorted merge, we
** could easily merge many doclists in parallel.  With some
** comprehension of the storage format, we could merge all of the
** doclists within a leaf node directly from the leaf node's storage.
** It may be worthwhile to merge smaller doclists before larger
** doclists, since they can be traversed more quickly - but the
** results may have less overlap, making them more expensive in a
** different way.
*/

/* Scan pReader for pTerm/nTerm, and merge the term's doclist over
** *out (any doclists with duplicate docids overwrite those in *out).
** Internal function for loadSegmentLeaf().
*/
static int loadSegmentLeavesInt(fulltext_vtab *v, LeavesReader *pReader,
                                const char *pTerm, int nTerm, int isPrefix,
                                DataBuffer *out){
  /* doclist data is accumulated into pBuffers similar to how one does
  ** increment in binary arithmetic.  If index 0 is empty, the data is
  ** stored there.  If there is data there, it is merged and the
  ** results carried into position 1, with further merge-and-carry
  ** until an empty position is found.
  */
  DataBuffer *pBuffers = NULL;
  int nBuffers = 0, nMaxBuffers = 0, rc;

  assert( nTerm>0 );


  for(rc=SQLITE_OK; rc==SQLITE_OK && !leavesReaderAtEnd(pReader);
      rc=leavesReaderStep(v, pReader)){
    /* TODO(shess) Really want leavesReaderTermCmp(), but that name is
    ** already taken to compare the terms of two LeavesReaders.  Think
    ** on a better name.  [Meanwhile, break encapsulation rather than
    ** use a confusing name.]
    */

    int c = leafReaderTermCmp(&pReader->leafReader, pTerm, nTerm, isPrefix);
    if( c>0 ) break;      /* Past any possible matches. */
    if( c==0 ){
      const char *pData = leavesReaderData(pReader);
      int iBuffer, nData = leavesReaderDataBytes(pReader);

      /* Find the first empty buffer. */
      for(iBuffer=0; iBuffer<nBuffers; ++iBuffer){
        if( 0==pBuffers[iBuffer].nData ) break;
      }

      /* Out of buffers, add an empty one. */
      if( iBuffer==nBuffers ){
        if( nBuffers==nMaxBuffers ){
          DataBuffer *p;
          nMaxBuffers += 20;

          /* Manual realloc so we can handle NULL appropriately. */
          p = sqlite3_malloc(nMaxBuffers*sizeof(*pBuffers));
          if( p==NULL ){
            rc = SQLITE_NOMEM;
            break;
          }

          if( nBuffers>0 ){
            assert(pBuffers!=NULL);
            memcpy(p, pBuffers, nBuffers*sizeof(*pBuffers));
            sqlite3_free(pBuffers);
          }
          pBuffers = p;
        }
        dataBufferInit(&(pBuffers[nBuffers]), 0);
        nBuffers++;
      }

      /* At this point, must have an empty at iBuffer. */
      assert(iBuffer<nBuffers && pBuffers[iBuffer].nData==0);

      /* If empty was first buffer, no need for merge logic. */
      if( iBuffer==0 ){
        dataBufferReplace(&(pBuffers[0]), pData, nData);
      }else{
        /* pAcc is the empty buffer the merged data will end up in. */
        DataBuffer *pAcc = &(pBuffers[iBuffer]);
        DataBuffer *p = &(pBuffers[0]);

        /* Handle position 0 specially to avoid need to prime pAcc
        ** with pData/nData.
        */
        dataBufferSwap(p, pAcc);
        docListAccumulateUnion(pAcc, pData, nData);

        /* Accumulate remaining doclists into pAcc. */
        for(++p; p<pAcc; ++p){
          docListAccumulateUnion(pAcc, p->pData, p->nData);

          /* dataBufferReset() could allow a large doclist to blow up
          ** our memory requirements.
          */
          if( p->nCapacity<1024 ){
            dataBufferReset(p);
          }else{
            dataBufferDestroy(p);
            dataBufferInit(p, 0);
          }
        }
      }
    }
  }

  /* Union all the doclists together into *out. */
  /* TODO(shess) What if *out is big?  Sigh. */
  if( rc==SQLITE_OK && nBuffers>0 ){
    int iBuffer;
    for(iBuffer=0; iBuffer<nBuffers; ++iBuffer){
      if( pBuffers[iBuffer].nData>0 ){
        if( out->nData==0 ){
          dataBufferSwap(out, &(pBuffers[iBuffer]));
        }else{
          docListAccumulateUnion(out, pBuffers[iBuffer].pData,
                                 pBuffers[iBuffer].nData);
        }
      }
    }
  }

  while( nBuffers-- ){
    dataBufferDestroy(&(pBuffers[nBuffers]));
  }
  if( pBuffers!=NULL ) sqlite3_free(pBuffers);

  return rc;
}

/* Call loadSegmentLeavesInt() with pData/nData as input. */
static int loadSegmentLeaf(fulltext_vtab *v, const char *pData, int nData,
                           const char *pTerm, int nTerm, int isPrefix,
                           DataBuffer *out){
  LeavesReader reader;

** interior node terms logically come between the blocks, so there is
** one more blockid than there are terms (that block contains terms >=
** the last interior-node term).
*/
/* TODO(shess) The calling code may already know that the end child is
** not worth calculating, because the end may be in a later sibling
** node.  Consider whether breaking symmetry is worthwhile.  I suspect
** it is not worthwhile.
*/
static void getChildrenContaining(const char *pData, int nData,
                                  const char *pTerm, int nTerm, int isPrefix,
                                  sqlite_int64 *piStartChild,
                                  sqlite_int64 *piEndChild){
  InteriorReader reader;

  dataBufferInit(&doclist, 0);

  /* Traverse the segments from oldest to newest so that newer doclist
  ** elements for given docids overwrite older elements.
  */
  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
    const char *pData = sqlite3_column_blob(s, 2);
    const int nData = sqlite3_column_bytes(s, 2);
    const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
    rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, isPrefix,
                     &doclist);
    if( rc!=SQLITE_OK ) goto err;
  }
  if( rc==SQLITE_DONE ){
    if( doclist.nData!=0 ){

  DataBuffer dl;

  /* Determine the next index at level 0, merging as necessary. */
  rc = segdirNextIndex(v, 0, &idx);
  if( rc!=SQLITE_OK ) return rc;

  n = fts2HashCount(pTerms);
  pData = sqlite3_malloc(n*sizeof(TermData));

  for(i = 0, e = fts2HashFirst(pTerms); e; i++, e = fts2HashNext(e)){
    assert( i<n );
    pData[i].pTerm = fts2HashKey(e);
    pData[i].nTerm = fts2HashKeysize(e);
    pData[i].pCollector = fts2HashData(e);
  }

                        pData[i].pTerm, pData[i].nTerm, dl.pData, dl.nData);
    if( rc!=SQLITE_OK ) goto err;
  }
  rc = leafWriterFinalize(v, &writer);

 err:
  dataBufferDestroy(&dl);
  sqlite3_free(pData);
  leafWriterDestroy(&writer);
  return rc;
}

/* If pendingTerms has data, free it. */
static int clearPendingTerms(fulltext_vtab *v){
  if( v->nPendingData>=0 ){

    fts2HashInit(&v->pendingTerms, FTS2_HASH_STRING, 1);
    v->nPendingData = 0;
  }
  v->iPrevDocid = iDocid;
  return SQLITE_OK;
}

/* This function implements the xUpdate callback; it is the top-level entry
 * point for inserting, deleting or updating a row in a full-text table. */
static int fulltextUpdate(sqlite3_vtab *pVtab, int nArg, sqlite3_value **ppArg,
                   sqlite_int64 *pRowid){
  fulltext_vtab *v = (fulltext_vtab *) pVtab;
  int rc;

  TRACE(("FTS2 Update %p\n", pVtab));

  if( nArg<2 ){
    rc = index_delete(v, sqlite3_value_int64(ppArg[0]));
    if( rc==SQLITE_OK ){
      /* If we just deleted the last row in the table, clear out the
      ** index data.
      */
      rc = content_exists(v);
      if( rc==SQLITE_ROW ){
        rc = SQLITE_OK;
      }else if( rc==SQLITE_DONE ){
        /* Clear the pending terms so we don't flush a useless level-0
        ** segment when the transaction closes.
        */
        rc = clearPendingTerms(v);
        if( rc==SQLITE_OK ){
          rc = segdir_delete_all(v);
        }
      }
    }
  } else if( sqlite3_value_type(ppArg[0]) != SQLITE_NULL ){
    /* An update:
     * ppArg[0] = old rowid
     * ppArg[1] = new rowid
     * ppArg[2..2+v->nColumn-1] = values
     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
     */

    snippetOffsetText(&pCursor->snippet);
    sqlite3_result_text(pContext,
                        pCursor->snippet.zOffset, pCursor->snippet.nOffset,
                        SQLITE_STATIC);
  }
}

/* OptLeavesReader is nearly identical to LeavesReader, except that
** where LeavesReader is geared towards the merging of complete
** segment levels (with exactly MERGE_COUNT segments), OptLeavesReader
** is geared towards implementation of the optimize() function, and
** can merge all segments simultaneously.  This version may be
** somewhat less efficient than LeavesReader because it merges into an
** accumulator rather than doing an N-way merge, but since segment
** size grows exponentially (so segment count logrithmically) this is
** probably not an immediate problem.
*/
/* TODO(shess): Prove that assertion, or extend the merge code to
** merge tree fashion (like the prefix-searching code does).
*/
/* TODO(shess): OptLeavesReader and LeavesReader could probably be
** merged with little or no loss of performance for LeavesReader.  The
** merged code would need to handle >MERGE_COUNT segments, and would
** also need to be able to optionally optimize away deletes.
*/
typedef struct OptLeavesReader {
  /* Segment number, to order readers by age. */
  int segment;
  LeavesReader reader;
} OptLeavesReader;

static int optLeavesReaderAtEnd(OptLeavesReader *pReader){
  return leavesReaderAtEnd(&pReader->reader);
}
static int optLeavesReaderTermBytes(OptLeavesReader *pReader){
  return leavesReaderTermBytes(&pReader->reader);
}
static const char *optLeavesReaderData(OptLeavesReader *pReader){
  return leavesReaderData(&pReader->reader);
}
static int optLeavesReaderDataBytes(OptLeavesReader *pReader){
  return leavesReaderDataBytes(&pReader->reader);
}
static const char *optLeavesReaderTerm(OptLeavesReader *pReader){
  return leavesReaderTerm(&pReader->reader);
}
static int optLeavesReaderStep(fulltext_vtab *v, OptLeavesReader *pReader){
  return leavesReaderStep(v, &pReader->reader);
}
static int optLeavesReaderTermCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
  return leavesReaderTermCmp(&lr1->reader, &lr2->reader);
}
/* Order by term ascending, segment ascending (oldest to newest), with
** exhausted readers to the end.
*/
static int optLeavesReaderCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
  int c = optLeavesReaderTermCmp(lr1, lr2);
  if( c!=0 ) return c;
  return lr1->segment-lr2->segment;
}
/* Bubble pLr[0] to appropriate place in pLr[1..nLr-1].  Assumes that
** pLr[1..nLr-1] is already sorted.
*/
static void optLeavesReaderReorder(OptLeavesReader *pLr, int nLr){
  while( nLr>1 && optLeavesReaderCmp(pLr, pLr+1)>0 ){
    OptLeavesReader tmp = pLr[0];
    pLr[0] = pLr[1];
    pLr[1] = tmp;
    nLr--;
    pLr++;
  }
}

/* optimize() helper function.  Put the readers in order and iterate
** through them, merging doclists for matching terms into pWriter.
** Returns SQLITE_OK on success, or the SQLite error code which
** prevented success.
*/
static int optimizeInternal(fulltext_vtab *v,
                            OptLeavesReader *readers, int nReaders,
                            LeafWriter *pWriter){
  int i, rc = SQLITE_OK;
  DataBuffer doclist, merged, tmp;

  /* Order the readers. */
  i = nReaders;
  while( i-- > 0 ){
    optLeavesReaderReorder(&readers[i], nReaders-i);
  }

  dataBufferInit(&doclist, LEAF_MAX);
  dataBufferInit(&merged, LEAF_MAX);

  /* Exhausted readers bubble to the end, so when the first reader is
  ** at eof, all are at eof.
  */
  while( !optLeavesReaderAtEnd(&readers[0]) ){

    /* Figure out how many readers share the next term. */
    for(i=1; i<nReaders && !optLeavesReaderAtEnd(&readers[i]); i++){
      if( 0!=optLeavesReaderTermCmp(&readers[0], &readers[i]) ) break;
    }

    /* Special-case for no merge. */
    if( i==1 ){
      /* Trim deletions from the doclist. */
      dataBufferReset(&merged);
      docListTrim(DL_DEFAULT,
                  optLeavesReaderData(&readers[0]),
                  optLeavesReaderDataBytes(&readers[0]),
                  -1, DL_DEFAULT, &merged);
    }else{
      DLReader dlReaders[MERGE_COUNT];
      int iReader, nReaders;

      /* Prime the pipeline with the first reader's doclist.  After
      ** one pass index 0 will reference the accumulated doclist.
      */
      dlrInit(&dlReaders[0], DL_DEFAULT,
              optLeavesReaderData(&readers[0]),
              optLeavesReaderDataBytes(&readers[0]));
      iReader = 1;

      assert( iReader<i );  /* Must execute the loop at least once. */
      while( iReader<i ){
        /* Merge 16 inputs per pass. */
        for( nReaders=1; iReader<i && nReaders<MERGE_COUNT;
             iReader++, nReaders++ ){
          dlrInit(&dlReaders[nReaders], DL_DEFAULT,
                  optLeavesReaderData(&readers[iReader]),
                  optLeavesReaderDataBytes(&readers[iReader]));
        }

        /* Merge doclists and swap result into accumulator. */
        dataBufferReset(&merged);
        docListMerge(&merged, dlReaders, nReaders);
        tmp = merged;
        merged = doclist;
        doclist = tmp;

        while( nReaders-- > 0 ){
          dlrDestroy(&dlReaders[nReaders]);
        }

        /* Accumulated doclist to reader 0 for next pass. */
        dlrInit(&dlReaders[0], DL_DEFAULT, doclist.pData, doclist.nData);
      }

      /* Destroy reader that was left in the pipeline. */
      dlrDestroy(&dlReaders[0]);

      /* Trim deletions from the doclist. */
      dataBufferReset(&merged);
      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
                  -1, DL_DEFAULT, &merged);
    }

    /* Only pass doclists with hits (skip if all hits deleted). */
    if( merged.nData>0 ){
      rc = leafWriterStep(v, pWriter,
                          optLeavesReaderTerm(&readers[0]),
                          optLeavesReaderTermBytes(&readers[0]),
                          merged.pData, merged.nData);
      if( rc!=SQLITE_OK ) goto err;
    }

    /* Step merged readers to next term and reorder. */
    while( i-- > 0 ){
      rc = optLeavesReaderStep(v, &readers[i]);
      if( rc!=SQLITE_OK ) goto err;

      optLeavesReaderReorder(&readers[i], nReaders-i);
    }
  }

 err:
  dataBufferDestroy(&doclist);
  dataBufferDestroy(&merged);
  return rc;
}

/* Implement optimize() function for FTS3.  optimize(t) merges all
** segments in the fts index into a single segment.  't' is the magic
** table-named column.
*/
static void optimizeFunc(sqlite3_context *pContext,
                         int argc, sqlite3_value **argv){
  fulltext_cursor *pCursor;
  if( argc>1 ){
    sqlite3_result_error(pContext, "excess arguments to optimize()",-1);
  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
    sqlite3_result_error(pContext, "illegal first argument to optimize",-1);
  }else{
    fulltext_vtab *v;
    int i, rc, iMaxLevel;
    OptLeavesReader *readers;
    int nReaders;
    LeafWriter writer;
    sqlite3_stmt *s;

    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
    v = cursor_vtab(pCursor);

    /* Flush any buffered updates before optimizing. */
    rc = flushPendingTerms(v);
    if( rc!=SQLITE_OK ) goto err;

    rc = segdir_count(v, &nReaders, &iMaxLevel);
    if( rc!=SQLITE_OK ) goto err;
    if( nReaders==0 || nReaders==1 ){
      sqlite3_result_text(pContext, "Index already optimal", -1,
                          SQLITE_STATIC);
      return;
    }

    rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
    if( rc!=SQLITE_OK ) goto err;

    readers = sqlite3_malloc(nReaders*sizeof(readers[0]));
    if( readers==NULL ) goto err;

    /* Note that there will already be a segment at this position
    ** until we call segdir_delete() on iMaxLevel.
    */
    leafWriterInit(iMaxLevel, 0, &writer);

    i = 0;
    while( (rc = sqlite3_step(s))==SQLITE_ROW ){
      sqlite_int64 iStart = sqlite3_column_int64(s, 0);
      sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
      const char *pRootData = sqlite3_column_blob(s, 2);
      int nRootData = sqlite3_column_bytes(s, 2);

      assert( i<nReaders );
      rc = leavesReaderInit(v, -1, iStart, iEnd, pRootData, nRootData,
                            &readers[i].reader);
      if( rc!=SQLITE_OK ) break;

      readers[i].segment = i;
      i++;
    }

    /* If we managed to successfully read them all, optimize them. */
    if( rc==SQLITE_DONE ){
      assert( i==nReaders );
      rc = optimizeInternal(v, readers, nReaders, &writer);
    }

    while( i-- > 0 ){
      leavesReaderDestroy(&readers[i].reader);
    }
    sqlite3_free(readers);

    /* If we've successfully gotten to here, delete the old segments
    ** and flush the interior structure of the new segment.
    */
    if( rc==SQLITE_OK ){
      for( i=0; i<=iMaxLevel; i++ ){
        rc = segdir_delete(v, i);
        if( rc!=SQLITE_OK ) break;
      }

      if( rc==SQLITE_OK ) rc = leafWriterFinalize(v, &writer);
    }

    leafWriterDestroy(&writer);

    if( rc!=SQLITE_OK ) goto err;

    sqlite3_result_text(pContext, "Index optimized", -1, SQLITE_STATIC);
    return;

    /* TODO(shess): Error-handling needs to be improved along the
    ** lines of the dump_ functions.
    */
 err:
    {
      char buf[512];
      sqlite3_snprintf(sizeof(buf), buf, "Error in optimize: %s",
                       sqlite3_errmsg(sqlite3_context_db_handle(pContext)));
      sqlite3_result_error(pContext, buf, -1);
    }
  }
}

#ifdef SQLITE_TEST
/* Generate an error of the form "<prefix>: <msg>".  If msg is NULL,
** pull the error from the context's db handle.
*/
static void generateError(sqlite3_context *pContext,
                          const char *prefix, const char *msg){
  char buf[512];
  if( msg==NULL ) msg = sqlite3_errmsg(sqlite3_context_db_handle(pContext));
  sqlite3_snprintf(sizeof(buf), buf, "%s: %s", prefix, msg);
  sqlite3_result_error(pContext, buf, -1);
}

/* Helper function to collect the set of terms in the segment into
** pTerms.  The segment is defined by the leaf nodes between
** iStartBlockid and iEndBlockid, inclusive, or by the contents of
** pRootData if iStartBlockid is 0 (in which case the entire segment
** fit in a leaf).
*/
static int collectSegmentTerms(fulltext_vtab *v, sqlite3_stmt *s,
                               fts2Hash *pTerms){
  const sqlite_int64 iStartBlockid = sqlite3_column_int64(s, 0);
  const sqlite_int64 iEndBlockid = sqlite3_column_int64(s, 1);
  const char *pRootData = sqlite3_column_blob(s, 2);
  const int nRootData = sqlite3_column_bytes(s, 2);
  LeavesReader reader;
  int rc = leavesReaderInit(v, 0, iStartBlockid, iEndBlockid,
                            pRootData, nRootData, &reader);
  if( rc!=SQLITE_OK ) return rc;

  while( rc==SQLITE_OK && !leavesReaderAtEnd(&reader) ){
    const char *pTerm = leavesReaderTerm(&reader);
    const int nTerm = leavesReaderTermBytes(&reader);
    void *oldValue = sqlite3Fts2HashFind(pTerms, pTerm, nTerm);
    void *newValue = (void *)((char *)oldValue+1);

    /* From the comment before sqlite3Fts2HashInsert in fts2_hash.c,
    ** the data value passed is returned in case of malloc failure.
    */
    if( newValue==sqlite3Fts2HashInsert(pTerms, pTerm, nTerm, newValue) ){
      rc = SQLITE_NOMEM;
    }else{
      rc = leavesReaderStep(v, &reader);
    }
  }

  leavesReaderDestroy(&reader);
  return rc;
}

/* Helper function to build the result string for dump_terms(). */
static int generateTermsResult(sqlite3_context *pContext, fts2Hash *pTerms){
  int iTerm, nTerms, nResultBytes, iByte;
  char *result;
  TermData *pData;
  fts2HashElem *e;

  /* Iterate pTerms to generate an array of terms in pData for
  ** sorting.
  */
  nTerms = fts2HashCount(pTerms);
  assert( nTerms>0 );
  pData = sqlite3_malloc(nTerms*sizeof(TermData));
  if( pData==NULL ) return SQLITE_NOMEM;

  nResultBytes = 0;
  for(iTerm = 0, e = fts2HashFirst(pTerms); e; iTerm++, e = fts2HashNext(e)){
    nResultBytes += fts2HashKeysize(e)+1;   /* Term plus trailing space */
    assert( iTerm<nTerms );
    pData[iTerm].pTerm = fts2HashKey(e);
    pData[iTerm].nTerm = fts2HashKeysize(e);
    pData[iTerm].pCollector = fts2HashData(e);  /* unused */
  }
  assert( iTerm==nTerms );

  assert( nResultBytes>0 );   /* nTerms>0, nResultsBytes must be, too. */
  result = sqlite3_malloc(nResultBytes);
  if( result==NULL ){
    sqlite3_free(pData);
    return SQLITE_NOMEM;
  }

  if( nTerms>1 ) qsort(pData, nTerms, sizeof(*pData), termDataCmp);

  /* Read the terms in order to build the result. */
  iByte = 0;
  for(iTerm=0; iTerm<nTerms; ++iTerm){
    memcpy(result+iByte, pData[iTerm].pTerm, pData[iTerm].nTerm);
    iByte += pData[iTerm].nTerm;
    result[iByte++] = ' ';
  }
  assert( iByte==nResultBytes );
  assert( result[nResultBytes-1]==' ' );
  result[nResultBytes-1] = '\0';

  /* Passes away ownership of result. */
  sqlite3_result_text(pContext, result, nResultBytes-1, sqlite3_free);
  sqlite3_free(pData);
  return SQLITE_OK;
}

/* Implements dump_terms() for use in inspecting the fts2 index from
** tests.  TEXT result containing the ordered list of terms joined by
** spaces.  dump_terms(t, level, idx) dumps the terms for the segment
** specified by level, idx (in %_segdir), while dump_terms(t) dumps
** all terms in the index.  In both cases t is the fts table's magic
** table-named column.
*/
static void dumpTermsFunc(
  sqlite3_context *pContext,
  int argc, sqlite3_value **argv
){
  fulltext_cursor *pCursor;
  if( argc!=3 && argc!=1 ){
    generateError(pContext, "dump_terms", "incorrect arguments");
  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
    generateError(pContext, "dump_terms", "illegal first argument");
  }else{
    fulltext_vtab *v;
    fts2Hash terms;
    sqlite3_stmt *s = NULL;
    int rc;

    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
    v = cursor_vtab(pCursor);

    /* If passed only the cursor column, get all segments.  Otherwise
    ** get the segment described by the following two arguments.
    */
    if( argc==1 ){
      rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
    }else{
      rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
      if( rc==SQLITE_OK ){
        rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[1]));
        if( rc==SQLITE_OK ){
          rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[2]));
        }
      }
    }

    if( rc!=SQLITE_OK ){
      generateError(pContext, "dump_terms", NULL);
      return;
    }

    /* Collect the terms for each segment. */
    sqlite3Fts2HashInit(&terms, FTS2_HASH_STRING, 1);
    while( (rc = sqlite3_step(s))==SQLITE_ROW ){
      rc = collectSegmentTerms(v, s, &terms);
      if( rc!=SQLITE_OK ) break;
    }

    if( rc!=SQLITE_DONE ){
      sqlite3_reset(s);
      generateError(pContext, "dump_terms", NULL);
    }else{
      const int nTerms = fts2HashCount(&terms);
      if( nTerms>0 ){
        rc = generateTermsResult(pContext, &terms);
        if( rc==SQLITE_NOMEM ){
          generateError(pContext, "dump_terms", "out of memory");
        }else{
          assert( rc==SQLITE_OK );
        }
      }else if( argc==3 ){
        /* The specific segment asked for could not be found. */
        generateError(pContext, "dump_terms", "segment not found");
      }else{
        /* No segments found. */
        /* TODO(shess): It should be impossible to reach this.  This
        ** case can only happen for an empty table, in which case
        ** SQLite has no rows to call this function on.
        */
        sqlite3_result_null(pContext);
      }
    }
    sqlite3Fts2HashClear(&terms);
  }
}

/* Expand the DL_DEFAULT doclist in pData into a text result in
** pContext.
*/
static void createDoclistResult(sqlite3_context *pContext,
                                const char *pData, int nData){
  DataBuffer dump;
  DLReader dlReader;

  assert( pData!=NULL && nData>0 );

  dataBufferInit(&dump, 0);
  dlrInit(&dlReader, DL_DEFAULT, pData, nData);
  for( ; !dlrAtEnd(&dlReader); dlrStep(&dlReader) ){
    char buf[256];
    PLReader plReader;

    plrInit(&plReader, &dlReader);
    if( DL_DEFAULT==DL_DOCIDS || plrAtEnd(&plReader) ){
      sqlite3_snprintf(sizeof(buf), buf, "[%lld] ", dlrDocid(&dlReader));
      dataBufferAppend(&dump, buf, strlen(buf));
    }else{
      int iColumn = plrColumn(&plReader);

      sqlite3_snprintf(sizeof(buf), buf, "[%lld %d[",
                       dlrDocid(&dlReader), iColumn);
      dataBufferAppend(&dump, buf, strlen(buf));

      for( ; !plrAtEnd(&plReader); plrStep(&plReader) ){
        if( plrColumn(&plReader)!=iColumn ){
          iColumn = plrColumn(&plReader);
          sqlite3_snprintf(sizeof(buf), buf, "] %d[", iColumn);
          assert( dump.nData>0 );
          dump.nData--;                     /* Overwrite trailing space. */
          assert( dump.pData[dump.nData]==' ');
          dataBufferAppend(&dump, buf, strlen(buf));
        }
        if( DL_DEFAULT==DL_POSITIONS_OFFSETS ){
          sqlite3_snprintf(sizeof(buf), buf, "%d,%d,%d ",
                           plrPosition(&plReader),
                           plrStartOffset(&plReader), plrEndOffset(&plReader));
        }else if( DL_DEFAULT==DL_POSITIONS ){
          sqlite3_snprintf(sizeof(buf), buf, "%d ", plrPosition(&plReader));
        }else{
          assert( NULL=="Unhandled DL_DEFAULT value");
        }
        dataBufferAppend(&dump, buf, strlen(buf));
      }
      plrDestroy(&plReader);

      assert( dump.nData>0 );
      dump.nData--;                     /* Overwrite trailing space. */
      assert( dump.pData[dump.nData]==' ');
      dataBufferAppend(&dump, "]] ", 3);
    }
  }
  dlrDestroy(&dlReader);

  assert( dump.nData>0 );
  dump.nData--;                     /* Overwrite trailing space. */
  assert( dump.pData[dump.nData]==' ');
  dump.pData[dump.nData] = '\0';
  assert( dump.nData>0 );

  /* Passes ownership of dump's buffer to pContext. */
  sqlite3_result_text(pContext, dump.pData, dump.nData, sqlite3_free);
  dump.pData = NULL;
  dump.nData = dump.nCapacity = 0;
}

/* Implements dump_doclist() for use in inspecting the fts2 index from
** tests.  TEXT result containing a string representation of the
** doclist for the indicated term.  dump_doclist(t, term, level, idx)
** dumps the doclist for term from the segment specified by level, idx
** (in %_segdir), while dump_doclist(t, term) dumps the logical
** doclist for the term across all segments.  The per-segment doclist
** can contain deletions, while the full-index doclist will not
** (deletions are omitted).
**
** Result formats differ with the setting of DL_DEFAULTS.  Examples:
**
** DL_DOCIDS: [1] [3] [7]
** DL_POSITIONS: [1 0[0 4] 1[17]] [3 1[5]]
** DL_POSITIONS_OFFSETS: [1 0[0,0,3 4,23,26] 1[17,102,105]] [3 1[5,20,23]]
**
** In each case the number after the outer '[' is the docid.  In the
** latter two cases, the number before the inner '[' is the column
** associated with the values within.  For DL_POSITIONS the numbers
** within are the positions, for DL_POSITIONS_OFFSETS they are the
** position, the start offset, and the end offset.
*/
static void dumpDoclistFunc(
  sqlite3_context *pContext,
  int argc, sqlite3_value **argv
){
  fulltext_cursor *pCursor;
  if( argc!=2 && argc!=4 ){
    generateError(pContext, "dump_doclist", "incorrect arguments");
  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
    generateError(pContext, "dump_doclist", "illegal first argument");
  }else if( sqlite3_value_text(argv[1])==NULL ||
            sqlite3_value_text(argv[1])[0]=='\0' ){
    generateError(pContext, "dump_doclist", "empty second argument");
  }else{
    const char *pTerm = (const char *)sqlite3_value_text(argv[1]);
    const int nTerm = strlen(pTerm);
    fulltext_vtab *v;
    int rc;
    DataBuffer doclist;

    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
    v = cursor_vtab(pCursor);

    dataBufferInit(&doclist, 0);

    /* termSelect() yields the same logical doclist that queries are
    ** run against.
    */
    if( argc==2 ){
      rc = termSelect(v, v->nColumn, pTerm, nTerm, 0, DL_DEFAULT, &doclist);
    }else{
      sqlite3_stmt *s = NULL;

      /* Get our specific segment's information. */
      rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
      if( rc==SQLITE_OK ){
        rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[2]));
        if( rc==SQLITE_OK ){
          rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[3]));
        }
      }

      if( rc==SQLITE_OK ){
        rc = sqlite3_step(s);

        if( rc==SQLITE_DONE ){
          dataBufferDestroy(&doclist);
          generateError(pContext, "dump_doclist", "segment not found");
          return;
        }

        /* Found a segment, load it into doclist. */
        if( rc==SQLITE_ROW ){
          const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
          const char *pData = sqlite3_column_blob(s, 2);
          const int nData = sqlite3_column_bytes(s, 2);

          /* loadSegment() is used by termSelect() to load each
          ** segment's data.
          */
          rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, 0,
                           &doclist);
          if( rc==SQLITE_OK ){
            rc = sqlite3_step(s);

            /* Should not have more than one matching segment. */
            if( rc!=SQLITE_DONE ){
              sqlite3_reset(s);
              dataBufferDestroy(&doclist);
              generateError(pContext, "dump_doclist", "invalid segdir");
              return;
            }
            rc = SQLITE_OK;
          }
        }
      }

      sqlite3_reset(s);
    }

    if( rc==SQLITE_OK ){
      if( doclist.nData>0 ){
        createDoclistResult(pContext, doclist.pData, doclist.nData);
      }else{
        /* TODO(shess): This can happen if the term is not present, or
        ** if all instances of the term have been deleted and this is
        ** an all-index dump.  It may be interesting to distinguish
        ** these cases.
        */
        sqlite3_result_text(pContext, "", 0, SQLITE_STATIC);
      }
    }else if( rc==SQLITE_NOMEM ){
      /* Handle out-of-memory cases specially because if they are
      ** generated in fts2 code they may not be reflected in the db
      ** handle.
      */
      /* TODO(shess): Handle this more comprehensively.
      ** sqlite3ErrStr() has what I need, but is internal.
      */
      generateError(pContext, "dump_doclist", "out of memory");
    }else{
      generateError(pContext, "dump_doclist", NULL);
    }

    dataBufferDestroy(&doclist);
  }
}
#endif

/*
** This routine implements the xFindFunction method for the FTS2
** virtual table.
*/
static int fulltextFindFunction(
  sqlite3_vtab *pVtab,
  int nArg,
  const char *zName,
  void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
  void **ppArg
){
  if( strcmp(zName,"snippet")==0 ){
    *pxFunc = snippetFunc;
    return 1;
  }else if( strcmp(zName,"offsets")==0 ){
    *pxFunc = snippetOffsetsFunc;
    return 1;
  }else if( strcmp(zName,"optimize")==0 ){
    *pxFunc = optimizeFunc;
    return 1;
#ifdef SQLITE_TEST
    /* NOTE(shess): These functions are present only for testing
    ** purposes.  No particular effort is made to optimize their
    ** execution or how they build their results.
    */
  }else if( strcmp(zName,"dump_terms")==0 ){
    /* fprintf(stderr, "Found dump_terms\n"); */
    *pxFunc = dumpTermsFunc;
    return 1;
  }else if( strcmp(zName,"dump_doclist")==0 ){
    /* fprintf(stderr, "Found dump_doclist\n"); */
    *pxFunc = dumpDoclistFunc;
    return 1;
#endif
  }
  return 0;
}

/*
** Rename an fts2 table.
*/

  ** the two scalar functions. If this is successful, register the
  ** module with sqlite.
  */
  if( SQLITE_OK==rc 
   && SQLITE_OK==(rc = sqlite3Fts2InitHashTable(db, pHash, "fts2_tokenizer"))
   && SQLITE_OK==(rc = sqlite3_overload_function(db, "snippet", -1))
   && SQLITE_OK==(rc = sqlite3_overload_function(db, "offsets", -1))
   && SQLITE_OK==(rc = sqlite3_overload_function(db, "optimize", -1))
#ifdef SQLITE_TEST
   && SQLITE_OK==(rc = sqlite3_overload_function(db, "dump_terms", -1))
   && SQLITE_OK==(rc = sqlite3_overload_function(db, "dump_doclist", -1))
#endif
  ){
    return sqlite3_create_module_v2(
        db, "fts2", &fts2Module, (void *)pHash, hashDestroy
    );
  }

  /* An error has occurred. Delete the hash table and return the error code. */
  assert( rc!=SQLITE_OK );
  if( pHash ){
    sqlite3Fts2HashClear(pHash);
    sqlite3_free(pHash);
  }
  return rc;
}

*/
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS2)

#include <assert.h>
#include <stdlib.h>
#include <string.h>

#include "sqlite3.h"
#include "fts2_hash.h"

/*
** Malloc and Free functions
*/
static void *fts2HashMalloc(int n){
  void *p = sqlite3_malloc(n);
  if( p ){
    memset(p, 0, n);
  }
  return p;
}
static void fts2HashFree(void *p){
  sqlite3_free(p);
}

/* Turn bulk memory into a hash table object by initializing the
** fields of the Hash structure.
**
** "pNew" is a pointer to the hash table that is to be initialized.
** keyClass is one of the constants 

  assert( keyClass>=FTS2_HASH_STRING && keyClass<=FTS2_HASH_BINARY );
  pNew->keyClass = keyClass;
  pNew->copyKey = copyKey;
  pNew->first = 0;
  pNew->count = 0;
  pNew->htsize = 0;
  pNew->ht = 0;


}

/* Remove all entries from a hash table.  Reclaim all memory.
** Call this routine to delete a hash table or to reset a hash table
** to the empty state.
*/
void sqlite3Fts2HashClear(fts2Hash *pH){
  fts2HashElem *elem;         /* For looping over all elements of the table */

  assert( pH!=0 );
  elem = pH->first;
  pH->first = 0;
  fts2HashFree(pH->ht);
  pH->ht = 0;
  pH->htsize = 0;
  while( elem ){
    fts2HashElem *next_elem = elem->next;
    if( pH->copyKey && elem->pKey ){
      fts2HashFree(elem->pKey);
    }
    fts2HashFree(elem);
    elem = next_elem;
  }
  pH->count = 0;
}

/*
** Hash and comparison functions when the mode is FTS2_HASH_STRING

*/
static void rehash(fts2Hash *pH, int new_size){
  struct _fts2ht *new_ht;          /* The new hash table */
  fts2HashElem *elem, *next_elem;  /* For looping over existing elements */
  int (*xHash)(const void*,int);   /* The hash function */

  assert( (new_size & (new_size-1))==0 );
  new_ht = (struct _fts2ht *)fts2HashMalloc( new_size*sizeof(struct _fts2ht) );
  if( new_ht==0 ) return;
  fts2HashFree(pH->ht);
  pH->ht = new_ht;
  pH->htsize = new_size;
  xHash = hashFunction(pH->keyClass);
  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
    next_elem = elem->next;
    insertElement(pH, &new_ht[h], elem);

    pEntry->chain = elem->next;
  }
  pEntry->count--;
  if( pEntry->count<=0 ){
    pEntry->chain = 0;
  }
  if( pH->copyKey && elem->pKey ){
    fts2HashFree(elem->pKey);
  }
  fts2HashFree( elem );
  pH->count--;
  if( pH->count<=0 ){
    assert( pH->first==0 );
    assert( pH->count==0 );
    fts2HashClear(pH);
  }
}

      removeElementGivenHash(pH,elem,h);
    }else{
      elem->data = data;
    }
    return old_data;
  }
  if( data==0 ) return 0;
  new_elem = (fts2HashElem*)fts2HashMalloc( sizeof(fts2HashElem) );
  if( new_elem==0 ) return data;
  if( pH->copyKey && pKey!=0 ){
    new_elem->pKey = fts2HashMalloc( nKey );
    if( new_elem->pKey==0 ){
      fts2HashFree(new_elem);
      return data;
    }
    memcpy((void*)new_elem->pKey, pKey, nKey);
  }else{
    new_elem->pKey = (void*)pKey;
  }
  new_elem->nKey = nKey;
  pH->count++;
  if( pH->htsize==0 ){
    rehash(pH,8);
    if( pH->htsize==0 ){
      pH->count = 0;
      fts2HashFree(new_elem);
      return data;
    }
  }
  if( pH->count > pH->htsize ){
    rehash(pH,pH->htsize*2);
  }
  assert( pH->htsize>0 );

** this structure opaque.
*/
struct fts2Hash {
  char keyClass;          /* HASH_INT, _POINTER, _STRING, _BINARY */
  char copyKey;           /* True if copy of key made on insert */
  int count;              /* Number of entries in this table */
  fts2HashElem *first;    /* The first element of the array */


  int htsize;             /* Number of buckets in the hash table */
  struct _fts2ht {        /* the hash table */
    int count;               /* Number of entries with this hash */
    fts2HashElem *chain;     /* Pointer to first entry with this hash */
  } *ht;
};

#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS2)


#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>


#include "fts2_tokenizer.h"

/*
** Class derived from sqlite3_tokenizer
*/
typedef struct porter_tokenizer {

** Create a new tokenizer instance.
*/
static int porterCreate(
  int argc, const char * const *argv,
  sqlite3_tokenizer **ppTokenizer
){
  porter_tokenizer *t;
  t = (porter_tokenizer *) sqlite3_malloc(sizeof(*t));
  if( t==NULL ) return SQLITE_NOMEM;
  memset(t, 0, sizeof(*t));
  *ppTokenizer = &t->base;
  return SQLITE_OK;
}

/*
** Destroy a tokenizer
*/
static int porterDestroy(sqlite3_tokenizer *pTokenizer){
  sqlite3_free(pTokenizer);
  return SQLITE_OK;
}

/*
** Prepare to begin tokenizing a particular string.  The input
** string to be tokenized is zInput[0..nInput-1].  A cursor
** used to incrementally tokenize this string is returned in 
** *ppCursor.
*/
static int porterOpen(
  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
  const char *zInput, int nInput,        /* String to be tokenized */
  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
){
  porter_tokenizer_cursor *c;

  c = (porter_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
  if( c==NULL ) return SQLITE_NOMEM;

  c->zInput = zInput;
  if( zInput==0 ){
    c->nInput = 0;
  }else if( nInput<0 ){
    c->nInput = (int)strlen(zInput);

/*
** Close a tokenization cursor previously opened by a call to
** porterOpen() above.
*/
static int porterClose(sqlite3_tokenizer_cursor *pCursor){
  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
  sqlite3_free(c->zToken);
  sqlite3_free(c);
  return SQLITE_OK;
}
/*
** Vowel or consonant
*/
static const char cType[] = {
   0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0,

      c->iOffset++;
    }

    if( c->iOffset>iStartOffset ){
      int n = c->iOffset-iStartOffset;
      if( n>c->nAllocated ){
        c->nAllocated = n+20;
        c->zToken = sqlite3_realloc(c->zToken, c->nAllocated);
        if( c->zToken==NULL ) return SQLITE_NOMEM;
      }
      porter_stemmer(&z[iStartOffset], n, c->zToken, pnBytes);
      *pzToken = c->zToken;
      *piStartOffset = iStartOffset;
      *piEndOffset = c->iOffset;
      *piPosition = c->iToken++;

  sqlite3_bind_blob(pStmt, 2, &p, sizeof(p), SQLITE_STATIC);
  sqlite3_step(pStmt);

  return sqlite3_finalize(pStmt);
}

static
int queryFts2Tokenizer(
  sqlite3 *db, 
  char *zName,  
  const sqlite3_tokenizer_module **pp
){
  int rc;
  sqlite3_stmt *pStmt;
  const char zSql[] = "SELECT fts2_tokenizer(?)";

/*
** Implementation of the scalar function fts2_tokenizer_internal_test().
** This function is used for testing only, it is not included in the
** build unless SQLITE_TEST is defined.
**
** The purpose of this is to test that the fts2_tokenizer() function
** can be used as designed by the C-code in the queryFts2Tokenizer and
** registerTokenizer() functions above. These two functions are repeated
** in the README.tokenizer file as an example, so it is important to
** test them.
**
** To run the tests, evaluate the fts2_tokenizer_internal_test() scalar
** function with no arguments. An assert() will fail if a problem is
** detected. i.e.:

  int rc;
  const sqlite3_tokenizer_module *p1;
  const sqlite3_tokenizer_module *p2;
  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);

  /* Test the query function */
  sqlite3Fts2SimpleTokenizerModule(&p1);
  rc = queryFts2Tokenizer(db, "simple", &p2);
  assert( rc==SQLITE_OK );
  assert( p1==p2 );
  rc = queryFts2Tokenizer(db, "nosuchtokenizer", &p2);
  assert( rc==SQLITE_ERROR );
  assert( p2==0 );
  assert( 0==strcmp(sqlite3_errmsg(db), "unknown tokenizer: nosuchtokenizer") );

  /* Test the storage function */
  rc = registerTokenizer(db, "nosuchtokenizer", p1);
  assert( rc==SQLITE_OK );
  rc = queryFts2Tokenizer(db, "nosuchtokenizer", &p2);
  assert( rc==SQLITE_OK );
  assert( p2==p1 );

  sqlite3_result_text(context, "ok", -1, SQLITE_STATIC);
}

#endif

#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS2)


#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>


#include "fts2_tokenizer.h"

typedef struct simple_tokenizer {
  sqlite3_tokenizer base;
  char delim[128];             /* flag ASCII delimiters */
} simple_tokenizer;

*/
static int simpleCreate(
  int argc, const char * const *argv,
  sqlite3_tokenizer **ppTokenizer
){
  simple_tokenizer *t;

  t = (simple_tokenizer *) sqlite3_malloc(sizeof(*t));
  if( t==NULL ) return SQLITE_NOMEM;
  memset(t, 0, sizeof(*t));

  /* TODO(shess) Delimiters need to remain the same from run to run,
  ** else we need to reindex.  One solution would be a meta-table to
  ** track such information in the database, then we'd only want this
  ** information on the initial create.
  */
  if( argc>1 ){
    int i, n = strlen(argv[1]);
    for(i=0; i<n; i++){
      unsigned char ch = argv[1][i];
      /* We explicitly don't support UTF-8 delimiters for now. */
      if( ch>=0x80 ){
        sqlite3_free(t);
        return SQLITE_ERROR;
      }
      t->delim[ch] = 1;
    }
  } else {
    /* Mark non-alphanumeric ASCII characters as delimiters */
    int i;
    for(i=1; i<0x80; i++){
      t->delim[i] = !((i>='0' && i<='9') || (i>='A' && i<='Z') ||
                      (i>='a' && i<='z'));
    }
  }

  *ppTokenizer = &t->base;
  return SQLITE_OK;
}

/*
** Destroy a tokenizer
*/
static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
  sqlite3_free(pTokenizer);
  return SQLITE_OK;
}

/*
** Prepare to begin tokenizing a particular string.  The input
** string to be tokenized is pInput[0..nBytes-1].  A cursor
** used to incrementally tokenize this string is returned in 
** *ppCursor.
*/
static int simpleOpen(
  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
  const char *pInput, int nBytes,        /* String to be tokenized */
  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
){
  simple_tokenizer_cursor *c;

  c = (simple_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
  if( c==NULL ) return SQLITE_NOMEM;

  c->pInput = pInput;
  if( pInput==0 ){
    c->nBytes = 0;
  }else if( nBytes<0 ){
    c->nBytes = (int)strlen(pInput);

/*
** Close a tokenization cursor previously opened by a call to
** simpleOpen() above.
*/
static int simpleClose(sqlite3_tokenizer_cursor *pCursor){
  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
  sqlite3_free(c->pToken);
  sqlite3_free(c);
  return SQLITE_OK;
}

/*
** Extract the next token from a tokenization cursor.  The cursor must
** have been opened by a prior call to simpleOpen().
*/

      c->iOffset++;
    }

    if( c->iOffset>iStartOffset ){
      int i, n = c->iOffset-iStartOffset;
      if( n>c->nTokenAllocated ){
        c->nTokenAllocated = n+20;
        c->pToken = sqlite3_realloc(c->pToken, c->nTokenAllocated);
        if( c->pToken==NULL ) return SQLITE_NOMEM;
      }
      for(i=0; i<n; i++){
        /* TODO(shess) This needs expansion to handle UTF-8
        ** case-insensitivity.
        */
        unsigned char ch = p[iStartOffset+i];
        c->pToken[i] = (ch>='A' && ch<='Z') ? (ch - 'A' + 'a') : ch;
      }
      *ppToken = c->pToken;
      *pnBytes = n;
      *piStartOffset = iStartOffset;
      *piEndOffset = c->iOffset;
      *piPosition = c->iToken++;

//
#include "afxres.h"

/////////////////////////////////////////////////////////////////////////////
#undef APSTUDIO_READONLY_SYMBOLS

/////////////////////////////////////////////////////////////////////////////
// English (United States) resources

#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)

LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
#pragma code_page(1252)


#ifdef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//
// TEXTINCLUDE
//

        BLOCK "040904b0"
        BEGIN
            VALUE "Comments", "http://sqlite.phxsoftware.com"
            VALUE "FileDescription", "System.Data.SQLite Interop Library"
            VALUE "FileVersion", "1.0.67.0"
            VALUE "InternalName", "SQLite.Interop.DLL"
            VALUE "LegalCopyright", "Released to the public domain"
            VALUE "OriginalFilename", "SQLite3.DLL 3.7.4"
            VALUE "ProductName", "System.Data.SQLite"
            VALUE "ProductVersion", "1.0"
        END
    END
    BLOCK "VarFileInfo"
    BEGIN
        VALUE "Translation", 0x409, 1200
    END
END

#endif    // English (United States) resources
/////////////////////////////////////////////////////////////////////////////



#ifndef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//

	Keyword="Win32Proj"
	TargetFrameworkVersion="131072"
	>
	<Platforms>
		<Platform
			Name="Win32"
		/>






		<Platform
			Name="x64"
		/>
	</Platforms>
	<ToolFiles>
	</ToolFiles>
	<Configurations>

				ModuleDefinitionFile="src\sqlite3.def"
				EmbedManagedResourceFile=""
				DelayLoadDLLs="advapi32.dll"
				RandomizedBaseAddress="1"
				DataExecutionPrevention="0"
				ImportLibrary=""
				TargetMachine="1"



















































































































































































				KeyFile="..\System.Data.SQLite\System.Data.SQLite.snk"
				CLRUnmanagedCodeCheck="true"
			/>
			<Tool
				Name="VCALinkTool"
			/>
			<Tool

			<Tool
				Name="VCAppVerifierTool"
			/>
			<Tool
				Name="VCPostBuildEventTool"
				CommandLine=""
			/>








































































































































































		</Configuration>
		<Configuration
			Name="Debug|x64"
			OutputDirectory="$(PlatformName)\$(ConfigurationName)"
			IntermediateDirectory="$(PlatformName)\$(ConfigurationName)"
			ConfigurationType="2"
			CharacterSet="2"

			<Tool
				Name="VCAppVerifierTool"
			/>
			<Tool
				Name="VCPostBuildEventTool"
				CommandLine=""
			/>







































































































































































		</Configuration>
		<Configuration
			Name="StockDebug|x64"
			OutputDirectory="$(PlatformName)\$(ConfigurationName)"
			IntermediateDirectory="$(PlatformName)\$(ConfigurationName)"
			ConfigurationType="2"
			CharacterSet="2"

				<FileConfiguration
					Name="Release|Win32"
					>
					<Tool
						Name="VCManagedResourceCompilerTool"
						ResourceFileName="$(IntDir)\System.Data.SQLite.$(InputName).resources"
					/>

















				</FileConfiguration>
				<FileConfiguration
					Name="Release|x64"
					>
					<Tool
						Name="VCManagedResourceCompilerTool"
						ResourceFileName="$(IntDir)\System.Data.SQLite.$(InputName).resources"
					/>
				</FileConfiguration>
				<FileConfiguration
					Name="Debug|Win32"
					ExcludedFromBuild="true"
					>
					<Tool
						Name="VCManagedResourceCompilerTool"
					/>
















				</FileConfiguration>
				<FileConfiguration
					Name="Debug|x64"
					ExcludedFromBuild="true"
					>
					<Tool
						Name="VCManagedResourceCompilerTool"
					/>
				</FileConfiguration>
				<FileConfiguration
					Name="StockDebug|Win32"
					ExcludedFromBuild="true"
					>
















					<Tool
						Name="VCManagedResourceCompilerTool"
					/>
				</FileConfiguration>
				<FileConfiguration
					Name="StockDebug|x64"
					ExcludedFromBuild="true"

<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <ItemGroup Label="ProjectConfigurations">
    <ProjectConfiguration Include="Debug|Win32">
      <Configuration>Debug</Configuration>
      <Platform>Win32</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="Debug|x64">
      <Configuration>Debug</Configuration>
      <Platform>x64</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="Release|Win32">
      <Configuration>Release</Configuration>
      <Platform>Win32</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="Release|x64">
      <Configuration>Release</Configuration>
      <Platform>x64</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="StockDebug|Win32">
      <Configuration>StockDebug</Configuration>
      <Platform>Win32</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="StockDebug|x64">
      <Configuration>StockDebug</Configuration>
      <Platform>x64</Platform>
    </ProjectConfiguration>
  </ItemGroup>
  <PropertyGroup Label="Globals">
    <ProjectGuid>{10B51CE8-A838-44DE-BD82-B658F0296F80}</ProjectGuid>
    <RootNamespace>SQLite.Interop</RootNamespace>
    <Keyword>Win32Proj</Keyword>
  </PropertyGroup>
  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'" Label="Configuration">
    <ConfigurationType>DynamicLibrary</ConfigurationType>
    <CharacterSet>MultiByte</CharacterSet>
    <CLRSupport>false</CLRSupport>
    <WholeProgramOptimization>false</WholeProgramOptimization>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
    <ConfigurationType>DynamicLibrary</ConfigurationType>
    <CharacterSet>MultiByte</CharacterSet>
    <CLRSupport>false</CLRSupport>
    <WholeProgramOptimization>false</WholeProgramOptimization>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
    <ConfigurationType>DynamicLibrary</ConfigurationType>
    <CharacterSet>MultiByte</CharacterSet>
    <CLRSupport>false</CLRSupport>
    <WholeProgramOptimization>true</WholeProgramOptimization>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'" Label="Configuration">
    <ConfigurationType>DynamicLibrary</ConfigurationType>
    <CharacterSet>MultiByte</CharacterSet>
    <CLRSupport>false</CLRSupport>
    <WholeProgramOptimization>false</WholeProgramOptimization>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="Configuration">
    <ConfigurationType>DynamicLibrary</ConfigurationType>
    <CharacterSet>MultiByte</CharacterSet>
    <CLRSupport>false</CLRSupport>
    <WholeProgramOptimization>false</WholeProgramOptimization>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="Configuration">
    <ConfigurationType>DynamicLibrary</ConfigurationType>
    <CharacterSet>MultiByte</CharacterSet>
    <CLRSupport>false</CLRSupport>
    <WholeProgramOptimization>true</WholeProgramOptimization>
  </PropertyGroup>
  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
  <ImportGroup Label="ExtensionSettings">
  </ImportGroup>
  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'" Label="PropertySheets">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="PropertySheets">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="PropertySheets">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'" Label="PropertySheets">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="PropertySheets">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="PropertySheets">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <PropertyGroup Label="UserMacros" />
  <PropertyGroup>
    <_ProjectFileVersion>10.0.30319.1</_ProjectFileVersion>
    <OutDir Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">$(SolutionDir)bin\</OutDir>
    <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">$(Configuration)\</IntDir>
    <GenerateManifest Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">false</GenerateManifest>
    <EmbedManifest Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</EmbedManifest>
    <OutDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">..\bin\x64\</OutDir>
    <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">x64\$(Configuration)\</IntDir>
    <EmbedManifest Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</EmbedManifest>
    <OutDir Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">$(SolutionDir)bin\</OutDir>
    <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">$(Configuration)\</IntDir>
    <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">false</LinkIncremental>
    <EmbedManifest Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</EmbedManifest>
    <OutDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">$(Platform)\$(Configuration)\</OutDir>
    <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">$(Platform)\$(Configuration)\</IntDir>
    <EmbedManifest Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</EmbedManifest>
    <OutDir Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">$(SolutionDir)bin\</OutDir>
    <IntDir Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">$(Configuration)\</IntDir>
    <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">false</LinkIncremental>
    <EmbedManifest Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">true</EmbedManifest>
    <OutDir Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'">$(Platform)\$(Configuration)\</OutDir>
    <IntDir Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'">$(Platform)\$(Configuration)\</IntDir>
    <EmbedManifest Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'">true</EmbedManifest>
    <CodeAnalysisRuleSet Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRules Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" />
    <CodeAnalysisRuleAssemblies Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" />
    <CodeAnalysisRuleSet Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRules Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" />
    <CodeAnalysisRuleAssemblies Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" />
    <CodeAnalysisRuleSet Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRules Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" />
    <CodeAnalysisRuleAssemblies Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" />
    <CodeAnalysisRuleSet Condition="'$(Configuration)|$(Platform)'=='Release|x64'">AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRules Condition="'$(Configuration)|$(Platform)'=='Release|x64'" />
    <CodeAnalysisRuleAssemblies Condition="'$(Configuration)|$(Platform)'=='Release|x64'" />
    <CodeAnalysisRuleSet Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRules Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'" />
    <CodeAnalysisRuleAssemblies Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'" />
    <CodeAnalysisRuleSet Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'">AllRules.ruleset</CodeAnalysisRuleSet>
    <CodeAnalysisRules Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'" />
    <CodeAnalysisRuleAssemblies Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'" />
    <TargetName Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">System.Data.SQLite</TargetName>
    <TargetName Condition="'$(Configuration)|$(Platform)'=='Release|x64'">System.Data.SQLite</TargetName>
    <PostBuildEventUseInBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">false</PostBuildEventUseInBuild>
    <PostBuildEventUseInBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">false</PostBuildEventUseInBuild>
    <PostBuildEventUseInBuild Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">false</PostBuildEventUseInBuild>
  </PropertyGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
    <PreBuildEvent>
      <Command>
      </Command>
    </PreBuildEvent>
    <ClCompile>
      <AdditionalOptions>/GS- %(AdditionalOptions)</AdditionalOptions>
      <Optimization>MaxSpeed</Optimization>
      <FavorSizeOrSpeed>Speed</FavorSizeOrSpeed>
      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;_CRT_SECURE_NO_DEPRECATE;NO_TCL;THREADSAFE=1;SQLITE_HAS_CODEC;SQLITE_ENABLE_COLUMN_METADATA;SQLITE_ENABLE_FTS3;SQLITE_ENABLE_RTREE;SQLITE_ENABLE_LOAD_EXTENSION;SQLITE_SOUNDEX;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <StringPooling>true</StringPooling>
      <ExceptionHandling>
      </ExceptionHandling>
    </ClCompile>
    <EmbeddedResource>
      <LogicalName>$(IntDir)System.Data.SQLite.%(Filename).resources</LogicalName>
    </EmbeddedResource>
    <Link>
      <AdditionalOptions>/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteCommand.bmp,System.Data.SQLite.SQLiteCommand.bmp
/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteConnection.bmp,System.Data.SQLite.SQLiteConnection.bmp
/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteDataAdapter.bmp,System.Data.SQLite.SQLiteDataAdapter.bmp %(AdditionalOptions)</AdditionalOptions>
      <AdditionalDependencies>..\System.Data.SQLite\bin\System.Data.SQLite.netmodule;%(AdditionalDependencies)</AdditionalDependencies>
      <OutputFile>../bin/System.Data.SQLite.DLL</OutputFile>
      <IgnoreSpecificDefaultLibraries>%(IgnoreSpecificDefaultLibraries)</IgnoreSpecificDefaultLibraries>
      <ModuleDefinitionFile>src\sqlite3.def</ModuleDefinitionFile>
      <EmbedManagedResourceFile>%(EmbedManagedResourceFile)</EmbedManagedResourceFile>
      <DelayLoadDLLs>advapi32.dll;%(DelayLoadDLLs)</DelayLoadDLLs>
      <RandomizedBaseAddress>false</RandomizedBaseAddress>
      <DataExecutionPrevention>
      </DataExecutionPrevention>
      <ImportLibrary>
      </ImportLibrary>
      <TargetMachine>MachineX86</TargetMachine>
      <KeyFile>..\System.Data.SQLite\System.Data.SQLite.snk</KeyFile>
      <CLRUnmanagedCodeCheck>true</CLRUnmanagedCodeCheck>
      <DelaySign>true</DelaySign>
    </Link>
    <PostBuildEvent>
      <Command>"$(FrameworkSDKDir)Bin\sn.exe" -R "$(TargetPath)" "$(SolutionDir)System.Data.SQLite\System.Data.SQLite.snk"</Command>
    </PostBuildEvent>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
    <PreBuildEvent>
      <Command>
      </Command>
    </PreBuildEvent>
    <Midl>
      <TargetEnvironment>X64</TargetEnvironment>
    </Midl>
    <ClCompile>
      <AdditionalOptions>/GS- %(AdditionalOptions)</AdditionalOptions>
      <Optimization>MaxSpeed</Optimization>
      <FavorSizeOrSpeed>Speed</FavorSizeOrSpeed>
      <PreprocessorDefinitions>NDEBUG;_WINDOWS;_USRDLL;_CRT_SECURE_NO_DEPRECATE;NO_TCL;THREADSAFE=1;WIN64;SQLITE_HAS_CODEC;SQLITE_ENABLE_COLUMN_METADATA;SQLITE_ENABLE_FTS3;SQLITE_ENABLE_RTREE;SQLITE_ENABLE_LOAD_EXTENSION;SQLITE_SOUNDEX;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <StringPooling>true</StringPooling>
      <ExceptionHandling>
      </ExceptionHandling>
      <BufferSecurityCheck>false</BufferSecurityCheck>
      <FunctionLevelLinking>true</FunctionLevelLinking>
      <RuntimeTypeInfo>false</RuntimeTypeInfo>
    </ClCompile>
    <EmbeddedResource>
      <LogicalName>$(IntDir)System.Data.SQLite.%(Filename).resources</LogicalName>
    </EmbeddedResource>
    <Link>
      <AdditionalOptions>/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteCommand.bmp,System.Data.SQLite.SQLiteCommand.bmp
/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteConnection.bmp,System.Data.SQLite.SQLiteConnection.bmp
/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteDataAdapter.bmp,System.Data.SQLite.SQLiteDataAdapter.bmp %(AdditionalOptions)</AdditionalOptions>
      <AdditionalDependencies>..\System.Data.SQLite\bin\System.Data.SQLite.netmodule;%(AdditionalDependencies)</AdditionalDependencies>
      <OutputFile>../bin/x64/System.Data.SQLite.DLL</OutputFile>
      <ModuleDefinitionFile>src\sqlite3.def</ModuleDefinitionFile>
      <EmbedManagedResourceFile>%(EmbedManagedResourceFile)</EmbedManagedResourceFile>
      <DelayLoadDLLs>advapi32.dll;%(DelayLoadDLLs)</DelayLoadDLLs>
      <RandomizedBaseAddress>false</RandomizedBaseAddress>
      <DataExecutionPrevention>
      </DataExecutionPrevention>
      <ImportLibrary>
      </ImportLibrary>
      <TargetMachine>MachineX64</TargetMachine>
      <KeyFile>..\System.Data.SQLite\System.Data.SQLite.snk</KeyFile>
      <CLRUnmanagedCodeCheck>true</CLRUnmanagedCodeCheck>
      <DelaySign>true</DelaySign>
    </Link>
    <PostBuildEvent>
      <Command>"$(FrameworkSDKDir).\Bin\sn.exe" -R "$(TargetPath)" "..\System.Data.SQLite\System.Data.SQLite.snk"</Command>
    </PostBuildEvent>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
    <PreBuildEvent>
      <Command>
      </Command>
    </PreBuildEvent>
    <ClCompile>
      <AdditionalOptions>/GS- %(AdditionalOptions)</AdditionalOptions>
      <Optimization>Disabled</Optimization>
      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;_CRT_SECURE_NO_DEPRECATE;NO_TCL;THREADSAFE=1;SQLITE_HAS_CODEC;SQLITE_ENABLE_COLUMN_METADATA;SQLITE_ENABLE_FTS3;SQLITE_ENABLE_RTREE;SQLITE_ENABLE_LOAD_EXTENSION;SQLITE_SOUNDEX;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
      <RuntimeTypeInfo>false</RuntimeTypeInfo>
      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
    </ClCompile>
    <Link>
      <ModuleDefinitionFile>src\sqlite3.def</ModuleDefinitionFile>
      <EmbedManagedResourceFile>%(EmbedManagedResourceFile)</EmbedManagedResourceFile>
      <DelayLoadDLLs>advapi32.dll;%(DelayLoadDLLs)</DelayLoadDLLs>
      <GenerateDebugInformation>true</GenerateDebugInformation>
      <ImportLibrary>
      </ImportLibrary>
    </Link>
    <PostBuildEvent>
      <Command>"$(FrameworkSDKDir)Bin\sn.exe" -R "$(TargetPath)" "$(SolutionDir)System.Data.SQLite\System.Data.SQLite.snk"</Command>
    </PostBuildEvent>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
    <PreBuildEvent>
      <Command>
      </Command>
    </PreBuildEvent>
    <Midl>
      <TargetEnvironment>X64</TargetEnvironment>
    </Midl>
    <ClCompile>
      <AdditionalOptions>/GS- %(AdditionalOptions)</AdditionalOptions>
      <Optimization>Disabled</Optimization>
      <PreprocessorDefinitions>SQLITE_DEBUG;_DEBUG;_WINDOWS;_USRDLL;_CRT_SECURE_NO_DEPRECATE;NO_TCL;THREADSAFE=1;WIN64;SQLITE_HAS_CODEC;SQLITE_ENABLE_COLUMN_METADATA;SQLITE_ENABLE_FTS3;SQLITE_ENABLE_RTREE;SQLITE_ENABLE_LOAD_EXTENSION;SQLITE_SOUNDEX;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
      <RuntimeTypeInfo>false</RuntimeTypeInfo>
      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
    </ClCompile>
    <Link>
      <OutputFile>../bin/x64/$(ProjectName).DLL</OutputFile>
      <ModuleDefinitionFile>src\sqlite3.def</ModuleDefinitionFile>
      <EmbedManagedResourceFile>%(EmbedManagedResourceFile)</EmbedManagedResourceFile>
      <DelayLoadDLLs>advapi32.dll;%(DelayLoadDLLs)</DelayLoadDLLs>
      <GenerateDebugInformation>true</GenerateDebugInformation>
      <RandomizedBaseAddress>false</RandomizedBaseAddress>
      <DataExecutionPrevention>
      </DataExecutionPrevention>
      <ImportLibrary>
      </ImportLibrary>
      <TargetMachine>MachineX64</TargetMachine>
      <KeyFile>..\System.Data.SQLite\System.Data.SQLite.snk</KeyFile>
    </Link>
    <PostBuildEvent>
      <Command>"$(FrameworkSDKDir).\Bin\sn.exe" -R "$(TargetPath)" "..\System.Data.SQLite\System.Data.SQLite.snk"</Command>
    </PostBuildEvent>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">
    <PreBuildEvent>
      <Command>
      </Command>
    </PreBuildEvent>
    <ClCompile>
      <AdditionalOptions>/GS- %(AdditionalOptions)</AdditionalOptions>
      <Optimization>Disabled</Optimization>
      <PreprocessorDefinitions>WIN32;SQLITE_DEBUG;_DEBUG;_WINDOWS;_USRDLL;_CRT_SECURE_NO_DEPRECATE;NO_TCL;THREADSAFE=1;SQLITE_HAS_CODEC;SQLITE_ENABLE_COLUMN_METADATA;SQLITE_ENABLE_FTS3;SQLITE_ENABLE_RTREE;SQLITE_ENABLE_LOAD_EXTENSION;SQLITE_SOUNDEX;SQLITE_CORE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
      <RuntimeTypeInfo>false</RuntimeTypeInfo>
      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
    </ClCompile>
    <Link>
      <OutputFile>../bin/sqlite3.dll</OutputFile>
      <ModuleDefinitionFile>src\sqlite3.def</ModuleDefinitionFile>
      <EmbedManagedResourceFile>%(EmbedManagedResourceFile)</EmbedManagedResourceFile>
      <DelayLoadDLLs>advapi32.dll;%(DelayLoadDLLs)</DelayLoadDLLs>
      <GenerateDebugInformation>true</GenerateDebugInformation>
      <RandomizedBaseAddress>false</RandomizedBaseAddress>
      <DataExecutionPrevention>
      </DataExecutionPrevention>
      <ImportLibrary>
      </ImportLibrary>
      <TargetMachine>MachineX86</TargetMachine>
      <KeyFile>..\System.Data.SQLite\System.Data.SQLite.snk</KeyFile>
      <DelaySign>true</DelaySign>
    </Link>
    <PostBuildEvent>
      <Command>"$(FrameworkSDKDir)Bin\sn.exe" -R "$(TargetPath)" "$(SolutionDir)System.Data.SQLite\System.Data.SQLite.snk"</Command>
    </PostBuildEvent>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'">
    <PreBuildEvent>
      <Command>
      </Command>
    </PreBuildEvent>
    <Midl>
      <TargetEnvironment>X64</TargetEnvironment>
    </Midl>
    <ClCompile>
      <AdditionalOptions>/GS- %(AdditionalOptions)</AdditionalOptions>
      <Optimization>Disabled</Optimization>
      <PreprocessorDefinitions>SQLITE_DEBUG;_DEBUG;_WINDOWS;_USRDLL;_CRT_SECURE_NO_DEPRECATE;NO_TCL;THREADSAFE=1;WIN64;SQLITE_HAS_CODEC;SQLITE_ENABLE_COLUMN_METADATA;SQLITE_ENABLE_FTS3;SQLITE_ENABLE_RTREE;SQLITE_ENABLE_LOAD_EXTENSION;SQLITE_SOUNDEX;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
      <RuntimeTypeInfo>false</RuntimeTypeInfo>
      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
    </ClCompile>
    <Link>
      <OutputFile>../bin/x64/$(ProjectName).DLL</OutputFile>
      <ModuleDefinitionFile>src\sqlite3.def</ModuleDefinitionFile>
      <EmbedManagedResourceFile>%(EmbedManagedResourceFile)</EmbedManagedResourceFile>
      <DelayLoadDLLs>advapi32.dll;%(DelayLoadDLLs)</DelayLoadDLLs>
      <GenerateDebugInformation>true</GenerateDebugInformation>
      <RandomizedBaseAddress>false</RandomizedBaseAddress>
      <DataExecutionPrevention>
      </DataExecutionPrevention>
      <ImportLibrary>
      </ImportLibrary>
      <TargetMachine>MachineX64</TargetMachine>
      <KeyFile>..\System.Data.SQLite\System.Data.SQLite.snk</KeyFile>
      <DelaySign>true</DelaySign>
    </Link>
    <PostBuildEvent>
      <Command>"$(FrameworkSDKDir).\Bin\sn.exe" -R "$(TargetPath)" "..\System.Data.SQLite\System.Data.SQLite.snk"</Command>
    </PostBuildEvent>
  </ItemDefinitionGroup>
  <ItemGroup>
    <ClInclude Include="resource.h" />
    <ClInclude Include="src\sqlite3.h" />
  </ItemGroup>
  <ItemGroup>
    <ClCompile Include="interop.c" />
  </ItemGroup>
  <ItemGroup>
    <EmbeddedResource Include="..\System.Data.SQLite\SR.resx">
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
      <LogicalName Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">System.Data.SQLite.%(Filename).resources</LogicalName>
      <LogicalName Condition="'$(Configuration)|$(Platform)'=='Release|x64'">System.Data.SQLite.%(Filename).resources</LogicalName>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='StockDebug|Win32'">true</ExcludedFromBuild>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='StockDebug|x64'">true</ExcludedFromBuild>
    </EmbeddedResource>
  </ItemGroup>
  <ItemGroup>
    <ResourceCompile Include="SQLite.Interop.rc" />
  </ItemGroup>
  <ItemGroup>
    <ProjectReference Include="..\System.Data.SQLite\System.Data.SQLite - ManagedOnly.csproj">
      <Project>{ac139952-261a-4463-b6fa-aebc25283a66}</Project>
      <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
    </ProjectReference>
    <ProjectReference Include="..\System.Data.SQLite\System.Data.SQLite - Netmodule.csproj">
      <Project>{ac139952-261a-4463-b6fa-aebc25284a66}</Project>
      <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
    </ProjectReference>
  </ItemGroup>
  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
  <ImportGroup Label="ExtensionTargets">
  </ImportGroup>
</Project>

  {
    // Rewrite all the pages in the database using the new encryption key
    Pgno nPage;
    Pgno nSkip = PAGER_MJ_PGNO(p);
    DbPage *pPage;
    Pgno n;

    sqlite3PagerPagecount(p, &nPage);

    for(n = 1; n <= nPage; n ++)
    {
      if (n == nSkip) continue;
      rc = sqlite3PagerGet(p, n, &pPage);
      if(!rc)
      {
        rc = sqlite3PagerWrite(pPage);
        sqlite3PagerUnref(pPage);

/*
** 2005 February 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that used to generate VDBE code
** that implements the ALTER TABLE command.


*/
#include "sqliteInt.h"


/*
** The code in this file only exists if we are not omitting the
** ALTER TABLE logic from the build.
*/
#ifndef SQLITE_OMIT_ALTERTABLE

**     -> 'CREATE TABLE def(a, b, c)'
**
** sqlite_rename_table('CREATE INDEX i ON abc(a)', 'def')
**     -> 'CREATE INDEX i ON def(a, b, c)'
*/
static void renameTableFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
){
  unsigned char const *zSql = sqlite3_value_text(argv[0]);
  unsigned char const *zTableName = sqlite3_value_text(argv[1]);

  int token;
  Token tname;
  unsigned char const *zCsr = zSql;
  int len = 0;
  char *zRet;

  sqlite3 *db = sqlite3_context_db_handle(context);

  UNUSED_PARAMETER(NotUsed);

  /* The principle used to locate the table name in the CREATE TABLE 
  ** statement is that the table name is the first non-space token that
  ** is immediately followed by a TK_LP or TK_USING token.
  */
  if( zSql ){
    do {
      if( !*zCsr ){
        /* Ran out of input before finding an opening bracket. Return NULL. */
        return;
      }

      /* Store the token that zCsr points to in tname. */
      tname.z = (char*)zCsr;
      tname.n = len;

      /* Advance zCsr to the next token. Store that token type in 'token',
      ** and its length in 'len' (to be used next iteration of this loop).
      */
      do {
        zCsr += len;
        len = sqlite3GetToken(zCsr, &token);
      } while( token==TK_SPACE );
      assert( len>0 );
    } while( token!=TK_LP && token!=TK_USING );

    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", ((u8*)tname.z) - zSql, zSql, 
       zTableName, tname.z+tname.n);
    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
  }
}

/*
** This C function implements an SQL user function that is used by SQL code
** generated by the ALTER TABLE ... RENAME command to modify the definition
** of any foreign key constraints that use the table being renamed as the 
** parent table. It is passed three arguments:
**
**   1) The complete text of the CREATE TABLE statement being modified,
**   2) The old name of the table being renamed, and
**   3) The new name of the table being renamed.
**
** It returns the new CREATE TABLE statement. For example:
**
**   sqlite_rename_parent('CREATE TABLE t1(a REFERENCES t2)', 't2', 't3')
**       -> 'CREATE TABLE t1(a REFERENCES t3)'
*/
#ifndef SQLITE_OMIT_FOREIGN_KEY
static void renameParentFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
){
  sqlite3 *db = sqlite3_context_db_handle(context);
  char *zOutput = 0;
  char *zResult;
  unsigned char const *zInput = sqlite3_value_text(argv[0]);
  unsigned char const *zOld = sqlite3_value_text(argv[1]);
  unsigned char const *zNew = sqlite3_value_text(argv[2]);

  unsigned const char *z;         /* Pointer to token */
  int n;                          /* Length of token z */
  int token;                      /* Type of token */

  UNUSED_PARAMETER(NotUsed);
  for(z=zInput; *z; z=z+n){
    n = sqlite3GetToken(z, &token);
    if( token==TK_REFERENCES ){
      char *zParent;
      do {
        z += n;
        n = sqlite3GetToken(z, &token);
      }while( token==TK_SPACE );

      zParent = sqlite3DbStrNDup(db, (const char *)z, n);
      if( zParent==0 ) break;
      sqlite3Dequote(zParent);
      if( 0==sqlite3StrICmp((const char *)zOld, zParent) ){
        char *zOut = sqlite3MPrintf(db, "%s%.*s\"%w\"", 
            (zOutput?zOutput:""), z-zInput, zInput, (const char *)zNew
        );
        sqlite3DbFree(db, zOutput);
        zOutput = zOut;
        zInput = &z[n];
      }
      sqlite3DbFree(db, zParent);
    }
  }

  zResult = sqlite3MPrintf(db, "%s%s", (zOutput?zOutput:""), zInput), 
  sqlite3_result_text(context, zResult, -1, SQLITE_DYNAMIC);
  sqlite3DbFree(db, zOutput);
}
#endif

#ifndef SQLITE_OMIT_TRIGGER
/* This function is used by SQL generated to implement the
** ALTER TABLE command. The first argument is the text of a CREATE TRIGGER 
** statement. The second is a table name. The table name in the CREATE 
** TRIGGER statement is replaced with the third argument and the result 
** returned. This is analagous to renameTableFunc() above, except for CREATE
** TRIGGER, not CREATE INDEX and CREATE TABLE.
*/
static void renameTriggerFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
){
  unsigned char const *zSql = sqlite3_value_text(argv[0]);
  unsigned char const *zTableName = sqlite3_value_text(argv[1]);

  int token;
  Token tname;
  int dist = 3;
  unsigned char const *zCsr = zSql;
  int len = 0;
  char *zRet;

  sqlite3 *db = sqlite3_context_db_handle(context);

  UNUSED_PARAMETER(NotUsed);

  /* The principle used to locate the table name in the CREATE TRIGGER 
  ** statement is that the table name is the first token that is immediatedly
  ** preceded by either TK_ON or TK_DOT and immediatedly followed by one
  ** of TK_WHEN, TK_BEGIN or TK_FOR.
  */
  if( zSql ){
    do {

      if( !*zCsr ){
        /* Ran out of input before finding the table name. Return NULL. */
        return;
      }

      /* Store the token that zCsr points to in tname. */
      tname.z = (char*)zCsr;
      tname.n = len;

      /* Advance zCsr to the next token. Store that token type in 'token',
      ** and its length in 'len' (to be used next iteration of this loop).
      */
      do {
        zCsr += len;

        dist = 0;
      }
    } while( dist!=2 || (token!=TK_WHEN && token!=TK_FOR && token!=TK_BEGIN) );

    /* Variable tname now contains the token that is the old table-name
    ** in the CREATE TRIGGER statement.
    */
    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", ((u8*)tname.z) - zSql, zSql, 
       zTableName, tname.z+tname.n);
    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
  }
}
#endif   /* !SQLITE_OMIT_TRIGGER */

/*
** Register built-in functions used to help implement ALTER TABLE
*/
void sqlite3AlterFunctions(void){
  static SQLITE_WSD FuncDef aAlterTableFuncs[] = {
    FUNCTION(sqlite_rename_table,   2, 0, 0, renameTableFunc),
#ifndef SQLITE_OMIT_TRIGGER
    FUNCTION(sqlite_rename_trigger, 2, 0, 0, renameTriggerFunc),
#endif
#ifndef SQLITE_OMIT_FOREIGN_KEY
    FUNCTION(sqlite_rename_parent,  3, 0, 0, renameParentFunc),
#endif
  };
  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aAlterTableFuncs);

  for(i=0; i<ArraySize(aAlterTableFuncs); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);
  }
}

/*
** This function is used to create the text of expressions of the form:
**
**   name=<constant1> OR name=<constant2> OR ...
**
** If argument zWhere is NULL, then a pointer string containing the text 
** "name=<constant>" is returned, where <constant> is the quoted version
** of the string passed as argument zConstant. The returned buffer is
** allocated using sqlite3DbMalloc(). It is the responsibility of the
** caller to ensure that it is eventually freed.
**
** If argument zWhere is not NULL, then the string returned is 
** "<where> OR name=<constant>", where <where> is the contents of zWhere.
** In this case zWhere is passed to sqlite3DbFree() before returning.
** 
*/
static char *whereOrName(sqlite3 *db, char *zWhere, char *zConstant){
  char *zNew;
  if( !zWhere ){
    zNew = sqlite3MPrintf(db, "name=%Q", zConstant);
  }else{
    zNew = sqlite3MPrintf(db, "%s OR name=%Q", zWhere, zConstant);
    sqlite3DbFree(db, zWhere);
  }
  return zNew;
}

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
/*
** Generate the text of a WHERE expression which can be used to select all
** tables that have foreign key constraints that refer to table pTab (i.e.
** constraints for which pTab is the parent table) from the sqlite_master
** table.
*/
static char *whereForeignKeys(Parse *pParse, Table *pTab){
  FKey *p;
  char *zWhere = 0;
  for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
    zWhere = whereOrName(pParse->db, zWhere, p->pFrom->zName);
  }
  return zWhere;
}
#endif

/*
** Generate the text of a WHERE expression which can be used to select all
** temporary triggers on table pTab from the sqlite_temp_master table. If
** table pTab has no temporary triggers, or is itself stored in the 
** temporary database, NULL is returned.
*/
static char *whereTempTriggers(Parse *pParse, Table *pTab){
  Trigger *pTrig;
  char *zWhere = 0;

  const Schema *pTempSchema = pParse->db->aDb[1].pSchema; /* Temp db schema */

  /* If the table is not located in the temp-db (in which case NULL is 
  ** returned, loop through the tables list of triggers. For each trigger
  ** that is not part of the temp-db schema, add a clause to the WHERE 
  ** expression being built up in zWhere.
  */
  if( pTab->pSchema!=pTempSchema ){
    sqlite3 *db = pParse->db;
    for(pTrig=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){
      if( pTrig->pSchema==pTempSchema ){




        zWhere = whereOrName(db, zWhere, pTrig->zName);


      }
    }
  }
  if( zWhere ){
    char *zNew = sqlite3MPrintf(pParse->db, "type='trigger' AND (%s)", zWhere);
    sqlite3DbFree(pParse->db, zWhere);
    zWhere = zNew;
  }
  return zWhere;
}

/*
** Generate code to drop and reload the internal representation of table
** pTab from the database, including triggers and temporary triggers.
** Argument zName is the name of the table in the database schema at
** the time the generated code is executed. This can be different from
** pTab->zName if this function is being called to code part of an 
** "ALTER TABLE RENAME TO" statement.
*/
static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
  Vdbe *v;
  char *zWhere;
  int iDb;                   /* Index of database containing pTab */
#ifndef SQLITE_OMIT_TRIGGER
  Trigger *pTrig;
#endif

  v = sqlite3GetVdbe(pParse);
  if( NEVER(v==0) ) return;
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  assert( iDb>=0 );

#ifndef SQLITE_OMIT_TRIGGER
  /* Drop any table triggers from the internal schema. */
  for(pTrig=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){
    int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
    assert( iTrigDb==iDb || iTrigDb==1 );
    sqlite3VdbeAddOp4(v, OP_DropTrigger, iTrigDb, 0, 0, pTrig->zName, 0);
  }
#endif

  /* Drop the table and index from the internal schema.  */
  sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);

  /* Reload the table, index and permanent trigger schemas. */
  zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName);
  if( !zWhere ) return;
  sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, zWhere, P4_DYNAMIC);

  sqlite3 *db = pParse->db; /* Database connection */
  int nTabName;             /* Number of UTF-8 characters in zTabName */
  const char *zTabName;     /* Original name of the table */
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers */
#endif
  VTable *pVTab = 0;        /* Non-zero if this is a v-tab with an xRename() */
  int savedDbFlags;         /* Saved value of db->flags */

  savedDbFlags = db->flags;  
  if( NEVER(db->mallocFailed) ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );

  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_rename_table;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;
  db->flags |= SQLITE_PreferBuiltin;

  /* Get a NULL terminated version of the new table name. */
  zName = sqlite3NameFromToken(db, pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse, 
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  */
  if( sqlite3Strlen30(pTab->zName)>6 
   && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7)
  ){
    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto exit_rename_table;
  }

  }
#endif

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto exit_rename_table;
  }
  if( IsVirtual(pTab) ){
    pVTab = sqlite3GetVTable(db, pTab);
    if( pVTab->pVtab->pModule->xRename==0 ){
      pVTab = 0;
    }
  }
#endif

  /* Begin a transaction and code the VerifyCookie for database iDb. 
  ** Then modify the schema cookie (since the ALTER TABLE modifies the
  ** schema). Open a statement transaction if the table is a virtual
  ** table.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;
  }
  sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
  sqlite3ChangeCookie(pParse, iDb);

  /* If this is a virtual table, invoke the xRename() function if
  ** one is defined. The xRename() callback will modify the names
  ** of any resources used by the v-table implementation (including other
  ** SQLite tables) that are identified by the name of the virtual table.
  */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( pVTab ){
    int i = ++pParse->nMem;
    sqlite3VdbeAddOp4(v, OP_String8, 0, i, 0, zName, 0);
    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
    sqlite3MayAbort(pParse);
  }
#endif

  /* figure out how many UTF-8 characters are in zName */
  zTabName = pTab->zName;
  nTabName = sqlite3Utf8CharLen(zTabName, -1);

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  if( db->flags&SQLITE_ForeignKeys ){
    /* If foreign-key support is enabled, rewrite the CREATE TABLE 
    ** statements corresponding to all child tables of foreign key constraints
    ** for which the renamed table is the parent table.  */
    if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
      sqlite3NestedParse(pParse, 
          "UPDATE \"%w\".%s SET "
              "sql = sqlite_rename_parent(sql, %Q, %Q) "
              "WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere);
      sqlite3DbFree(db, zWhere);
    }
  }
#endif

  /* Modify the sqlite_master table to use the new table name. */
  sqlite3NestedParse(pParse,
      "UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
          "sql = sqlite_rename_table(sql, %Q), "
#else

        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqlite3DbFree(db, zWhere);
  }
#endif

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  if( db->flags&SQLITE_ForeignKeys ){
    FKey *p;
    for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
      Table *pFrom = p->pFrom;
      if( pFrom!=pTab ){
        reloadTableSchema(pParse, p->pFrom, pFrom->zName);
      }
    }
  }
#endif

  /* Drop and reload the internal table schema. */
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(db, pSrc);
  sqlite3DbFree(db, zName);
  db->flags = savedDbFlags;
}


/*
** Generate code to make sure the file format number is at least minFormat.
** The generated code will increase the file format number if necessary.
*/
void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
  Vdbe *v;
  v = sqlite3GetVdbe(pParse);
  /* The VDBE should have been allocated before this routine is called.
  ** If that allocation failed, we would have quit before reaching this
  ** point */
  if( ALWAYS(v) ){
    int r1 = sqlite3GetTempReg(pParse);
    int r2 = sqlite3GetTempReg(pParse);
    int j1;
    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT);
    sqlite3VdbeUsesBtree(v, iDb);
    sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
    j1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, r2);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3ReleaseTempReg(pParse, r1);
    sqlite3ReleaseTempReg(pParse, r2);
  }
}

/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
  Table *pNew;              /* Copy of pParse->pNewTable */
  Table *pTab;              /* Table being altered */
  int iDb;                  /* Database number */
  const char *zDb;          /* Database name */
  const char *zTab;         /* Table name */
  char *zCol;               /* Null-terminated column definition */
  Column *pCol;             /* The new column */
  Expr *pDflt;              /* Default value for the new column */
  sqlite3 *db;              /* The database connection; */

  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ) return;
  pNew = pParse->pNewTable;
  assert( pNew );


  assert( sqlite3BtreeHoldsAllMutexes(db) );
  iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
  zDb = db->aDb[iDb].zName;
  zTab = &pNew->zName[16];  /* Skip the "sqlite_altertab_" prefix on the name */
  pCol = &pNew->aCol[pNew->nCol-1];
  pDflt = pCol->pDflt;
  pTab = sqlite3FindTable(db, zTab, zDb);
  assert( pTab );

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */

  if( pCol->isPrimKey ){
    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
    return;
  }
  if( pNew->pIndex ){
    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
    return;
  }
  if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){
    sqlite3ErrorMsg(pParse, 
        "Cannot add a REFERENCES column with non-NULL default value");
    return;
  }
  if( pCol->notNull && !pDflt ){
    sqlite3ErrorMsg(pParse, 
        "Cannot add a NOT NULL column with default value NULL");
    return;
  }

    sqlite3ValueFree(pVal);
  }

  /* Modify the CREATE TABLE statement. */
  zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
  if( zCol ){
    char *zEnd = &zCol[pColDef->n-1];
    int savedDbFlags = db->flags;
    while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){
      *zEnd-- = '\0';
    }
    db->flags |= SQLITE_PreferBuiltin;
    sqlite3NestedParse(pParse, 
        "UPDATE \"%w\".%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
        "WHERE type = 'table' AND name = %Q", 
      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqlite3DbFree(db, zCol);
    db->flags = savedDbFlags;
  }

  /* If the default value of the new column is NULL, then set the file
  ** format to 2. If the default value of the new column is not NULL,
  ** the file format becomes 3.
  */
  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);

    goto exit_begin_add_column;
  }

  assert( pTab->addColOffset>0 );
  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);

  /* Put a copy of the Table struct in Parse.pNewTable for the
  ** sqlite3AddColumn() function and friends to modify.  But modify
  ** the name by adding an "sqlite_altertab_" prefix.  By adding this
  ** prefix, we insure that the name will not collide with an existing
  ** table because user table are not allowed to have the "sqlite_"
  ** prefix on their name.
  */
  pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
  if( !pNew ) goto exit_begin_add_column;
  pParse->pNewTable = pNew;
  pNew->nRef = 1;

  pNew->nCol = pTab->nCol;
  assert( pNew->nCol>0 );
  nAlloc = (((pNew->nCol-1)/8)*8)+8;
  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
  pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
  pNew->zName = sqlite3MPrintf(db, "sqlite_altertab_%s", pTab->zName);
  if( !pNew->aCol || !pNew->zName ){
    db->mallocFailed = 1;
    goto exit_begin_add_column;
  }
  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
  for(i=0; i<pNew->nCol; i++){
    Column *pCol = &pNew->aCol[i];
    pCol->zName = sqlite3DbStrDup(db, pCol->zName);
    pCol->zColl = 0;
    pCol->zType = 0;
    pCol->pDflt = 0;
    pCol->zDflt = 0;
  }
  pNew->pSchema = db->aDb[iDb].pSchema;
  pNew->addColOffset = pTab->addColOffset;
  pNew->nRef = 1;

  /* Begin a transaction and increment the schema cookie.  */
  sqlite3BeginWriteOperation(pParse, 0, iDb);

/*
** 2005 July 8
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code associated with the ANALYZE command.


*/
#ifndef SQLITE_OMIT_ANALYZE
#include "sqliteInt.h"

/*
** This routine generates code that opens the sqlite_stat1 table for
** writing with cursor iStatCur. If the library was built with the
** SQLITE_ENABLE_STAT2 macro defined, then the sqlite_stat2 table is
** opened for writing using cursor (iStatCur+1)
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** Similarly, if the sqlite_stat2 table does not exist and the library
** is compiled with SQLITE_ENABLE_STAT2 defined, it is created. 
**
** Argument zWhere may be a pointer to a buffer containing a table name,
** or it may be a NULL pointer. If it is not NULL, then all entries in
** the sqlite_stat1 and (if applicable) sqlite_stat2 tables associated
** with the named table are deleted. If zWhere==0, then code is generated
** to delete all stat table entries.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere      /* Delete entries associated with this table */
){
  static const struct {
    const char *zName;
    const char *zCols;
  } aTable[] = {
    { "sqlite_stat1", "tbl,idx,stat" },
#ifdef SQLITE_ENABLE_STAT2
    { "sqlite_stat2", "tbl,idx,sampleno,sample" },
#endif
  };

  int aRoot[] = {0, 0};
  u8 aCreateTbl[] = {0, 0};

  int i;
  sqlite3 *db = pParse->db;
  Db *pDb;



  Vdbe *v = sqlite3GetVdbe(pParse);

  if( v==0 ) return;
  assert( sqlite3BtreeHoldsAllMutexes(db) );
  assert( sqlite3VdbeDb(v)==db );
  pDb = &db->aDb[iDb];

  for(i=0; i<ArraySize(aTable); i++){
    const char *zTab = aTable[i].zName;
    Table *pStat;
    if( (pStat = sqlite3FindTable(db, zTab, pDb->zName))==0 ){
      /* The sqlite_stat[12] table does not exist. Create it. Note that a 
      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
      ** of the new table in register pParse->regRoot. This is important 
      ** because the OpenWrite opcode below will be needing it. */
      sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols

      );
      aRoot[i] = pParse->regRoot;
      aCreateTbl[i] = 1;
    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */




      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
        sqlite3NestedParse(pParse,
           "DELETE FROM %Q.%s WHERE tbl=%Q", pDb->zName, zTab, zWhere
        );
      }else{
        /* The sqlite_stat[12] table already exists.  Delete all rows. */

        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
      }
    }







  }

  /* Open the sqlite_stat[12] tables for writing. */
  for(i=0; i<ArraySize(aTable); i++){
    sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur+i, aRoot[i], iDb);
    sqlite3VdbeChangeP4(v, -1, (char *)3, P4_INT32);
    sqlite3VdbeChangeP5(v, aCreateTbl[i]);
  }
}

/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
  Parse *pParse,   /* Parser context */
  Table *pTab,     /* Table whose indices are to be analyzed */
  int iStatCur,    /* Index of VdbeCursor that writes the sqlite_stat1 table */
  int iMem         /* Available memory locations begin here */
){
  sqlite3 *db = pParse->db;    /* Database handle */
  Index *pIdx;                 /* An index to being analyzed */
  int iIdxCur;                 /* Cursor open on index being analyzed */

  Vdbe *v;                     /* The virtual machine being built up */
  int i;                       /* Loop counter */
  int topOfLoop;               /* The top of the loop */
  int endOfLoop;               /* The end of the loop */
  int addr = 0;                /* The address of an instruction */
  int jZeroRows = 0;           /* Jump from here if number of rows is zero */
  int iDb;                     /* Index of database containing pTab */
  int regTabname = iMem++;     /* Register containing table name */
  int regIdxname = iMem++;     /* Register containing index name */
  int regSampleno = iMem++;    /* Register containing next sample number */
  int regCol = iMem++;         /* Content of a column analyzed table */
  int regRec = iMem++;         /* Register holding completed record */
  int regTemp = iMem++;        /* Temporary use register */
  int regRowid = iMem++;       /* Rowid for the inserted record */

#ifdef SQLITE_ENABLE_STAT2
  int regTemp2 = iMem++;       /* Temporary use register */
  int regSamplerecno = iMem++; /* Index of next sample to record */
  int regRecno = iMem++;       /* Current sample index */
  int regLast = iMem++;        /* Index of last sample to record */
  int regFirst = iMem++;       /* Index of first sample to record */
#endif

  v = sqlite3GetVdbe(pParse);
  if( v==0 || NEVER(pTab==0) ){
    return;
  }
  if( pTab->tnum==0 ){
    /* Do not gather statistics on views or virtual tables */
    return;
  }
  if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
    /* Do not gather statistics on system tables */
    return;
  }
  assert( sqlite3BtreeHoldsAllMutexes(db) );
  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
  assert( iDb>=0 );
#ifndef SQLITE_OMIT_AUTHORIZATION
  if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
      db->aDb[iDb].zName ) ){
    return;
  }
#endif

  /* Establish a read-lock on the table at the shared-cache level. */
  sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);

  iIdxCur = pParse->nTab++;
  sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    int nCol = pIdx->nColumn;
    KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);



    if( iMem+1+(nCol*2)>pParse->nMem ){
      pParse->nMem = iMem+1+(nCol*2);

    }

    /* Open a cursor to the index to be analyzed. */

    assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );


    sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
        (char *)pKey, P4_KEYINFO_HANDOFF);
    VdbeComment((v, "%s", pIdx->zName));

    /* Populate the register containing the index name. */
    sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);

#ifdef SQLITE_ENABLE_STAT2

    /* If this iteration of the loop is generating code to analyze the
    ** first index in the pTab->pIndex list, then register regLast has
    ** not been populated. In this case populate it now.  */
    if( pTab->pIndex==pIdx ){
      sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regSamplerecno);
      sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2-1, regTemp);
      sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2, regTemp2);

      sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regLast);
      sqlite3VdbeAddOp2(v, OP_Null, 0, regFirst);
      addr = sqlite3VdbeAddOp3(v, OP_Lt, regSamplerecno, 0, regLast);
      sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regFirst);
      sqlite3VdbeAddOp3(v, OP_Multiply, regLast, regTemp, regLast);
      sqlite3VdbeAddOp2(v, OP_AddImm, regLast, SQLITE_INDEX_SAMPLES*2-2);
      sqlite3VdbeAddOp3(v, OP_Divide,  regTemp2, regLast, regLast);
      sqlite3VdbeJumpHere(v, addr);
    }

    /* Zero the regSampleno and regRecno registers. */
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regSampleno);
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regRecno);
    sqlite3VdbeAddOp2(v, OP_Copy, regFirst, regSamplerecno);
#endif

    /* The block of memory cells initialized here is used as follows.
    **
    **    iMem:                
    **        The total number of rows in the table.

    **
    **    iMem+1 .. iMem+nCol: 
    **        Number of distinct entries in index considering the 
    **        left-most N columns only, where N is between 1 and nCol, 
    **        inclusive.
    **
    **    iMem+nCol+1 .. Mem+2*nCol:  
    **        Previous value of indexed columns, from left to right.
    **
    ** Cells iMem through iMem+nCol are initialized to 0. The others are 
    ** initialized to contain an SQL NULL.
    */
    for(i=0; i<=nCol; i++){
      sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
    }
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
    }

    /* Start the analysis loop. This loop runs through all the entries in
    ** the index b-tree.  */
    endOfLoop = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
    topOfLoop = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);

    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
#ifdef SQLITE_ENABLE_STAT2
      if( i==0 ){
        /* Check if the record that cursor iIdxCur points to contains a
        ** value that should be stored in the sqlite_stat2 table. If so,
        ** store it.  */
        int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
        assert( regTabname+1==regIdxname 
             && regTabname+2==regSampleno
             && regTabname+3==regCol
        );
        sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
        sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 4, regRec, "aaab", 0);
        sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regRowid);
        sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regRec, regRowid);

        /* Calculate new values for regSamplerecno and regSampleno.
        **
        **   sampleno = sampleno + 1
        **   samplerecno = samplerecno+(remaining records)/(remaining samples)
        */
        sqlite3VdbeAddOp2(v, OP_AddImm, regSampleno, 1);
        sqlite3VdbeAddOp3(v, OP_Subtract, regRecno, regLast, regTemp);
        sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
        sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regTemp2);
        sqlite3VdbeAddOp3(v, OP_Subtract, regSampleno, regTemp2, regTemp2);
        sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regTemp, regTemp);
        sqlite3VdbeAddOp3(v, OP_Add, regSamplerecno, regTemp, regSamplerecno);

        sqlite3VdbeJumpHere(v, ne);
        sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
      }
#endif

      sqlite3VdbeAddOp3(v, OP_Ne, regCol, 0, iMem+nCol+i+1);
      /**** TODO:  add collating sequence *****/
      sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
    }
    if( db->mallocFailed ){
      /* If a malloc failure has occurred, then the result of the expression 
      ** passed as the second argument to the call to sqlite3VdbeJumpHere() 
      ** below may be negative. Which causes an assert() to fail (or an
      ** out-of-bounds write if SQLITE_DEBUG is not defined).  */
      return;
    }
    sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
    for(i=0; i<nCol; i++){
      sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-(nCol*2));
      sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
    }

    /* End of the analysis loop. */
    sqlite3VdbeResolveLabel(v, endOfLoop);
    sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);

    /* Store the results in sqlite_stat1.
    **
    ** The result is a single row of the sqlite_stat1 table.  The first
    ** two columns are the names of the table and index.  The third column
    ** is a string composed of a list of integer statistics about the
    ** index.  The first integer in the list is the total number of entries
    ** in the index.  There is one additional integer in the list for each
    ** column of the table.  This additional integer is a guess of how many
    ** rows of the table the index will select.  If D is the count of distinct
    ** values and K is the total number of rows, then the integer is computed
    ** as:
    **
    **        I = (K+D-1)/D
    **
    ** If K==0 then no entry is made into the sqlite_stat1 table.  
    ** If K>0 then it is always the case the D>0 so division by zero
    ** is never possible.
    */




    sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
    if( jZeroRows==0 ){
      jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
    }
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
      sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
      sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
      sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
      sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
    }
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
  }

  /* If the table has no indices, create a single sqlite_stat1 entry
  ** containing NULL as the index name and the row count as the content.
  */
  if( pTab->pIndex==0 ){
    sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
    VdbeComment((v, "%s", pTab->zName));
    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
  }else{
    assert( jZeroRows>0 );
    addr = sqlite3VdbeAddOp0(v, OP_Goto);
    sqlite3VdbeJumpHere(v, jZeroRows);
  }
  sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
  sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
  sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
  sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
  sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
  if( pParse->nMem<regRec ) pParse->nMem = regRec;
  if( jZeroRows ){
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*
** Generate code that will cause the most recent index analysis to
** be loaded into internal hash tables where is can be used.
*/
static void loadAnalysis(Parse *pParse, int iDb){
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp1(v, OP_LoadAnalysis, iDb);
  }
}

/*
** Generate code that will do an analysis of an entire database
*/
static void analyzeDatabase(Parse *pParse, int iDb){
  sqlite3 *db = pParse->db;
  Schema *pSchema = db->aDb[iDb].pSchema;    /* Schema of database iDb */
  HashElem *k;
  int iStatCur;
  int iMem;

  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 2;
  openStatTable(pParse, iDb, iStatCur, 0);
  iMem = pParse->nMem+1;
  for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
    Table *pTab = (Table*)sqliteHashData(k);
    analyzeOneTable(pParse, pTab, iStatCur, iMem);
  }
  loadAnalysis(pParse, iDb);

  int iDb;
  int iStatCur;

  assert( pTab!=0 );
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 2;
  openStatTable(pParse, iDb, iStatCur, pTab->zName);
  analyzeOneTable(pParse, pTab, iStatCur, pParse->nMem+1);
  loadAnalysis(pParse, iDb);
}

/*
** Generate code for the ANALYZE command.  The parser calls this routine

  /* Read the database schema. If an error occurs, leave an error message
  ** and code in pParse and return NULL. */
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    return;
  }

  assert( pName2!=0 || pName1==0 );
  if( pName1==0 ){
    /* Form 1:  Analyze everything */
    for(i=0; i<db->nDb; i++){
      if( i==1 ) continue;  /* Do not analyze the TEMP database */
      analyzeDatabase(pParse, i);
    }
  }else if( pName2->n==0 ){
    /* Form 2:  Analyze the database or table named */
    iDb = sqlite3FindDb(db, pName1);
    if( iDb>=0 ){
      analyzeDatabase(pParse, iDb);
    }else{
      z = sqlite3NameFromToken(db, pName1);
      if( z ){

  const char *zDatabase;
};

/*
** This callback is invoked once for each index when reading the
** sqlite_stat1 table.  
**
**     argv[0] = name of the table
**     argv[1] = name of the index (might be NULL)
**     argv[2] = results of analysis - on integer for each column
**
** Entries for which argv[1]==NULL simply record the number of rows in
** the table.
*/
static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
  analysisInfo *pInfo = (analysisInfo*)pData;
  Index *pIndex;
  Table *pTable;
  int i, c, n;
  unsigned int v;
  const char *z;

  assert( argc==3 );
  UNUSED_PARAMETER2(NotUsed, argc);

  if( argv==0 || argv[0]==0 || argv[2]==0 ){
    return 0;
  }
  pTable = sqlite3FindTable(pInfo->db, argv[0], pInfo->zDatabase);
  if( pTable==0 ){
    return 0;
  }
  if( argv[1] ){
    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
  }else{
    pIndex = 0;
  }
  n = pIndex ? pIndex->nColumn : 0;
  z = argv[2];
  for(i=0; *z && i<=n; i++){
    v = 0;
    while( (c=z[0])>='0' && c<='9' ){
      v = v*10 + c - '0';
      z++;
    }
    if( i==0 ) pTable->nRowEst = v;
    if( pIndex==0 ) break;
    pIndex->aiRowEst[i] = v;
    if( *z==' ' ) z++;
  }
  return 0;
}

/*
** If the Index.aSample variable is not NULL, delete the aSample[] array
** and its contents.
*/
void sqlite3DeleteIndexSamples(sqlite3 *db, Index *pIdx){
#ifdef SQLITE_ENABLE_STAT2
  if( pIdx->aSample ){
    int j;
    for(j=0; j<SQLITE_INDEX_SAMPLES; j++){
      IndexSample *p = &pIdx->aSample[j];
      if( p->eType==SQLITE_TEXT || p->eType==SQLITE_BLOB ){
        sqlite3DbFree(db, p->u.z);
      }
    }
    sqlite3DbFree(db, pIdx->aSample);
  }
#else
  UNUSED_PARAMETER(db);
  UNUSED_PARAMETER(pIdx);
#endif
}

/*
** Load the content of the sqlite_stat1 and sqlite_stat2 tables. The
** contents of sqlite_stat1 are used to populate the Index.aiRowEst[]
** arrays. The contents of sqlite_stat2 are used to populate the
** Index.aSample[] arrays.
**
** If the sqlite_stat1 table is not present in the database, SQLITE_ERROR
** is returned. In this case, even if SQLITE_ENABLE_STAT2 was defined 
** during compilation and the sqlite_stat2 table is present, no data is 
** read from it.
**
** If SQLITE_ENABLE_STAT2 was defined during compilation and the 
** sqlite_stat2 table is not present in the database, SQLITE_ERROR is
** returned. However, in this case, data is read from the sqlite_stat1
** table (if it is present) before returning.
**
** If an OOM error occurs, this function always sets db->mallocFailed.
** This means if the caller does not care about other errors, the return
** code may be ignored.
*/
int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
  analysisInfo sInfo;
  HashElem *i;
  char *zSql;
  int rc;

  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pBt!=0 );
  assert( sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );

  /* Clear any prior statistics */
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
    Index *pIdx = sqliteHashData(i);
    sqlite3DefaultRowEst(pIdx);
    sqlite3DeleteIndexSamples(db, pIdx);
    pIdx->aSample = 0;
  }

  /* Check to make sure the sqlite_stat1 table exists */
  sInfo.db = db;
  sInfo.zDatabase = db->aDb[iDb].zName;
  if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
    return SQLITE_ERROR;
  }


  /* Load new statistics out of the sqlite_stat1 table */
  zSql = sqlite3MPrintf(db, 
      "SELECT tbl, idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
  if( zSql==0 ){
    rc = SQLITE_NOMEM;
  }else{
    rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
    sqlite3DbFree(db, zSql);
  }


  /* Load the statistics from the sqlite_stat2 table. */
#ifdef SQLITE_ENABLE_STAT2
  if( rc==SQLITE_OK && !sqlite3FindTable(db, "sqlite_stat2", sInfo.zDatabase) ){
    rc = SQLITE_ERROR;
  }
  if( rc==SQLITE_OK ){
    sqlite3_stmt *pStmt = 0;

    zSql = sqlite3MPrintf(db, 
        "SELECT idx,sampleno,sample FROM %Q.sqlite_stat2", sInfo.zDatabase);
    if( !zSql ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
      sqlite3DbFree(db, zSql);
    }

    if( rc==SQLITE_OK ){
      while( sqlite3_step(pStmt)==SQLITE_ROW ){
        char *zIndex = (char *)sqlite3_column_text(pStmt, 0);
        Index *pIdx = sqlite3FindIndex(db, zIndex, sInfo.zDatabase);
        if( pIdx ){
          int iSample = sqlite3_column_int(pStmt, 1);
          if( iSample<SQLITE_INDEX_SAMPLES && iSample>=0 ){
            int eType = sqlite3_column_type(pStmt, 2);

            if( pIdx->aSample==0 ){
              static const int sz = sizeof(IndexSample)*SQLITE_INDEX_SAMPLES;
              pIdx->aSample = (IndexSample *)sqlite3DbMallocRaw(0, sz);
              if( pIdx->aSample==0 ){
                db->mallocFailed = 1;
                break;
              }
	      memset(pIdx->aSample, 0, sz);
            }

            assert( pIdx->aSample );
            {
              IndexSample *pSample = &pIdx->aSample[iSample];
              pSample->eType = (u8)eType;
              if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
                pSample->u.r = sqlite3_column_double(pStmt, 2);
              }else if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
                const char *z = (const char *)(
                    (eType==SQLITE_BLOB) ?
                    sqlite3_column_blob(pStmt, 2):
                    sqlite3_column_text(pStmt, 2)
                );
                int n = sqlite3_column_bytes(pStmt, 2);
                if( n>24 ){
                  n = 24;
                }
                pSample->nByte = (u8)n;
                if( n < 1){
                  pSample->u.z = 0;
                }else{
                  pSample->u.z = sqlite3DbStrNDup(0, z, n);
                  if( pSample->u.z==0 ){
                    db->mallocFailed = 1;
                    break;
                  }
                }
              }
            }
          }
        }
      }
      rc = sqlite3_finalize(pStmt);
    }
  }
#endif

  if( rc==SQLITE_NOMEM ){
    db->mallocFailed = 1;
  }
  return rc;
}


#endif /* SQLITE_OMIT_ANALYZE */

/*
** 2003 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the ATTACH and DETACH commands.


*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_ATTACH
/*
** Resolve an expression that was part of an ATTACH or DETACH statement. This
** is slightly different from resolving a normal SQL expression, because simple

** will fail because neither abc or def can be resolved.
*/
static int resolveAttachExpr(NameContext *pName, Expr *pExpr)
{
  int rc = SQLITE_OK;
  if( pExpr ){
    if( pExpr->op!=TK_ID ){
      rc = sqlite3ResolveExprNames(pName, pExpr);
      if( rc==SQLITE_OK && !sqlite3ExprIsConstant(pExpr) ){
        sqlite3ErrorMsg(pName->pParse, "invalid name: \"%s\"", pExpr->u.zToken);
        return SQLITE_ERROR;
      }
    }else{
      pExpr->op = TK_STRING;
    }
  }
  return rc;

**     SELECT sqlite_attach(x, y, z)
**
** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the
** third argument.
*/
static void attachFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
){
  int i;
  int rc = 0;
  sqlite3 *db = sqlite3_context_db_handle(context);
  const char *zName;
  const char *zFile;
  Db *aNew;
  char *zErrDyn = 0;

  UNUSED_PARAMETER(NotUsed);

  zFile = (const char *)sqlite3_value_text(argv[0]);
  zName = (const char *)sqlite3_value_text(argv[1]);
  if( zFile==0 ) zFile = "";
  if( zName==0 ) zName = "";

  /* Check for the following errors:
  **
  **     * Too many attached databases,
  **     * Transaction currently open
  **     * Specified database name already being used.
  */
  if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){

    zErrDyn = sqlite3MPrintf(db, "too many attached databases - max %d", 
      db->aLimit[SQLITE_LIMIT_ATTACHED]
    );
    goto attach_error;
  }
  if( !db->autoCommit ){

    zErrDyn = sqlite3MPrintf(db, "cannot ATTACH database within transaction");
    goto attach_error;
  }
  for(i=0; i<db->nDb; i++){
    char *z = db->aDb[i].zName;
    assert( z && zName );
    if( sqlite3StrICmp(z, zName)==0 ){

      zErrDyn = sqlite3MPrintf(db, "database %s is already in use", zName);
      goto attach_error;
    }
  }

  /* Allocate the new entry in the db->aDb[] array and initialise the schema
  ** hash tables.
  */
  if( db->aDb==db->aDbStatic ){
    aNew = sqlite3DbMallocRaw(db, sizeof(db->aDb[0])*3 );
    if( aNew==0 ) return;
    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
  }else{
    aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
    if( aNew==0 ) return;
  }
  db->aDb = aNew;
  aNew = &db->aDb[db->nDb];
  memset(aNew, 0, sizeof(*aNew));

  /* Open the database file. If the btree is successfully opened, use
  ** it to obtain the database schema. At this point the schema may
  ** or may not be initialised.
  */
  rc = sqlite3BtreeOpen(zFile, db, &aNew->pBt, 0,
                        db->openFlags | SQLITE_OPEN_MAIN_DB);
  db->nDb++;
  if( rc==SQLITE_CONSTRAINT ){
    rc = SQLITE_ERROR;
    zErrDyn = sqlite3MPrintf(db, "database is already attached");
  }else if( rc==SQLITE_OK ){
    Pager *pPager;
    aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
    if( !aNew->pSchema ){
      rc = SQLITE_NOMEM;
    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
      zErrDyn = sqlite3MPrintf(db, 
        "attached databases must use the same text encoding as main database");
      rc = SQLITE_ERROR;
    }
    pPager = sqlite3BtreePager(aNew->pBt);
    sqlite3PagerLockingMode(pPager, db->dfltLockMode);
    sqlite3BtreeSecureDelete(aNew->pBt,
                             sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );
  }
  aNew->safety_level = 3;
  aNew->zName = sqlite3DbStrDup(db, zName);
  if( rc==SQLITE_OK && aNew->zName==0 ){
    rc = SQLITE_NOMEM;
  }


#ifdef SQLITE_HAS_CODEC
  if( rc==SQLITE_OK ){
    extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
    int nKey;
    char *zKey;
    int t = sqlite3_value_type(argv[2]);
    switch( t ){
      case SQLITE_INTEGER:
      case SQLITE_FLOAT:
        zErrDyn = sqlite3DbStrDup(db, "Invalid key value");
        rc = SQLITE_ERROR;
        break;
        
      case SQLITE_TEXT:
      case SQLITE_BLOB:
        nKey = sqlite3_value_bytes(argv[2]);
        zKey = (char *)sqlite3_value_blob(argv[2]);
        rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
        break;

      case SQLITE_NULL:
        /* No key specified.  Use the key from the main database */
        sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
        rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
        break;
    }
  }
#endif

  /* If the file was opened successfully, read the schema for the new database.
  ** If this fails, or if opening the file failed, then close the file and 
  ** remove the entry from the db->aDb[] array. i.e. put everything back the way
  ** we found it.
  */
  if( rc==SQLITE_OK ){

    sqlite3BtreeEnterAll(db);
    rc = sqlite3Init(db, &zErrDyn);
    sqlite3BtreeLeaveAll(db);

  }
  if( rc ){
    int iDb = db->nDb - 1;
    assert( iDb>=2 );
    if( db->aDb[iDb].pBt ){
      sqlite3BtreeClose(db->aDb[iDb].pBt);
      db->aDb[iDb].pBt = 0;
      db->aDb[iDb].pSchema = 0;
    }
    sqlite3ResetInternalSchema(db, 0);
    db->nDb = iDb;
    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
      db->mallocFailed = 1;
      sqlite3DbFree(db, zErrDyn);
      zErrDyn = sqlite3MPrintf(db, "out of memory");
    }else if( zErrDyn==0 ){
      zErrDyn = sqlite3MPrintf(db, "unable to open database: %s", zFile);
    }
    goto attach_error;
  }
  
  return;

attach_error:
  /* Return an error if we get here */
  if( zErrDyn ){
    sqlite3_result_error(context, zErrDyn, -1);
    sqlite3DbFree(db, zErrDyn);



  }
  if( rc ) sqlite3_result_error_code(context, rc);
}

/*
** An SQL user-function registered to do the work of an DETACH statement. The
** three arguments to the function come directly from a detach statement:
**
**     DETACH DATABASE x
**
**     SELECT sqlite_detach(x)
*/
static void detachFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
){
  const char *zName = (const char *)sqlite3_value_text(argv[0]);
  sqlite3 *db = sqlite3_context_db_handle(context);
  int i;
  Db *pDb = 0;
  char zErr[128];

  UNUSED_PARAMETER(NotUsed);

  if( zName==0 ) zName = "";
  for(i=0; i<db->nDb; i++){
    pDb = &db->aDb[i];
    if( pDb->pBt==0 ) continue;
    if( sqlite3StrICmp(pDb->zName, zName)==0 ) break;
  }

    goto detach_error;
  }
  if( !db->autoCommit ){
    sqlite3_snprintf(sizeof(zErr), zErr,
                     "cannot DETACH database within transaction");
    goto detach_error;
  }
  if( sqlite3BtreeIsInReadTrans(pDb->pBt) || sqlite3BtreeIsInBackup(pDb->pBt) ){
    sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName);
    goto detach_error;
  }

  sqlite3BtreeClose(pDb->pBt);
  pDb->pBt = 0;
  pDb->pSchema = 0;

/*
** This procedure generates VDBE code for a single invocation of either the
** sqlite_detach() or sqlite_attach() SQL user functions.
*/
static void codeAttach(
  Parse *pParse,       /* The parser context */
  int type,            /* Either SQLITE_ATTACH or SQLITE_DETACH */
  FuncDef const *pFunc,/* FuncDef wrapper for detachFunc() or attachFunc() */

  Expr *pAuthArg,      /* Expression to pass to authorization callback */
  Expr *pFilename,     /* Name of database file */
  Expr *pDbname,       /* Name of the database to use internally */
  Expr *pKey           /* Database key for encryption extension */
){
  int rc;
  NameContext sName;
  Vdbe *v;

  sqlite3* db = pParse->db;
  int regArgs;
















  memset(&sName, 0, sizeof(NameContext));
  sName.pParse = pParse;

  if( 
      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
      SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
  ){
    pParse->nErr++;
    goto attach_end;
  }

#ifndef SQLITE_OMIT_AUTHORIZATION
  if( pAuthArg ){
    char *zAuthArg = pAuthArg->u.zToken;
    if( NEVER(zAuthArg==0) ){
      goto attach_end;
    }
    rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
    if(rc!=SQLITE_OK ){
      goto attach_end;
    }
  }
#endif /* SQLITE_OMIT_AUTHORIZATION */


  v = sqlite3GetVdbe(pParse);
  regArgs = sqlite3GetTempRange(pParse, 4);
  sqlite3ExprCode(pParse, pFilename, regArgs);
  sqlite3ExprCode(pParse, pDbname, regArgs+1);
  sqlite3ExprCode(pParse, pKey, regArgs+2);

  assert( v || db->mallocFailed );
  if( v ){
    sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-pFunc->nArg, regArgs+3);
    assert( pFunc->nArg==-1 || (pFunc->nArg&0xff)==pFunc->nArg );
    sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));

    sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);

    /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
    ** statement only). For DETACH, set it to false (expire all existing
    ** statements).
    */
    sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));

/*
** Called by the parser to compile a DETACH statement.
**
**     DETACH pDbname
*/
void sqlite3Detach(Parse *pParse, Expr *pDbname){
  static const FuncDef detach_func = {
    1,                /* nArg */
    SQLITE_UTF8,      /* iPrefEnc */
    0,                /* flags */
    0,                /* pUserData */
    0,                /* pNext */
    detachFunc,       /* xFunc */
    0,                /* xStep */
    0,                /* xFinalize */
    "sqlite_detach",  /* zName */
    0,                /* pHash */
    0                 /* pDestructor */
  };
  codeAttach(pParse, SQLITE_DETACH, &detach_func, pDbname, 0, 0, pDbname);
}

/*
** Called by the parser to compile an ATTACH statement.
**
**     ATTACH p AS pDbname KEY pKey
*/
void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *pKey){
  static const FuncDef attach_func = {
    3,                /* nArg */
    SQLITE_UTF8,      /* iPrefEnc */
    0,                /* flags */
    0,                /* pUserData */
    0,                /* pNext */
    attachFunc,       /* xFunc */
    0,                /* xStep */
    0,                /* xFinalize */
    "sqlite_attach",  /* zName */
    0,                /* pHash */
    0                 /* pDestructor */
  };
  codeAttach(pParse, SQLITE_ATTACH, &attach_func, p, p, pDbname, pKey);
}




#endif /* SQLITE_OMIT_ATTACH */






/*
** Initialize a DbFixer structure.  This routine must be called prior
** to passing the structure to one of the sqliteFixAAAA() routines below.
**
** The return value indicates whether or not fixation is required.  TRUE
** means we do need to fix the database references, FALSE means we do not.
*/
int sqlite3FixInit(
  DbFixer *pFix,      /* The fixer to be initialized */
  Parse *pParse,      /* Error messages will be written here */
  int iDb,            /* This is the database that must be used */
  const char *zType,  /* "view", "trigger", or "index" */
  const Token *pName  /* Name of the view, trigger, or index */
){
  sqlite3 *db;

  if( NEVER(iDb<0) || iDb==1 ) return 0;
  db = pParse->db;
  assert( db->nDb>iDb );
  pFix->pParse = pParse;
  pFix->zDb = db->aDb[iDb].zName;
  pFix->zType = zType;
  pFix->pName = pName;
  return 1;

  DbFixer *pFix,       /* Context of the fixation */
  SrcList *pList       /* The Source list to check and modify */
){
  int i;
  const char *zDb;
  struct SrcList_item *pItem;

  if( NEVER(pList==0) ) return 0;
  zDb = pFix->zDb;
  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
    if( pItem->zDatabase==0 ){
      pItem->zDatabase = sqlite3DbStrDup(pFix->pParse->db, zDb);
    }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){
      sqlite3ErrorMsg(pFix->pParse,
         "%s %T cannot reference objects in database %s",

  return 0;
}
int sqlite3FixExpr(
  DbFixer *pFix,     /* Context of the fixation */
  Expr *pExpr        /* The expression to be fixed to one database */
){
  while( pExpr ){
    if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ) break;
    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
      if( sqlite3FixSelect(pFix, pExpr->x.pSelect) ) return 1;

    }else{
      if( sqlite3FixExprList(pFix, pExpr->x.pList) ) return 1;

    }
    if( sqlite3FixExpr(pFix, pExpr->pRight) ){
      return 1;
    }
    pExpr = pExpr->pLeft;
  }
  return 0;

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the sqlite3_set_authorizer()
** API.  This facility is an optional feature of the library.  Embedded
** systems that do not need this facility may omit it by recompiling
** the library with -DSQLITE_OMIT_AUTHORIZATION=1


*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/

  return SQLITE_OK;
}

/*
** Write an error message into pParse->zErrMsg that explains that the
** user-supplied authorization function returned an illegal value.
*/
static void sqliteAuthBadReturnCode(Parse *pParse){
  sqlite3ErrorMsg(pParse, "authorizer malfunction");
  pParse->rc = SQLITE_ERROR;
}

/*
** Invoke the authorization callback for permission to read column zCol from
** table zTab in database zDb. This function assumes that an authorization
** callback has been registered (i.e. that sqlite3.xAuth is not NULL).
**
** If SQLITE_IGNORE is returned and pExpr is not NULL, then pExpr is changed
** to an SQL NULL expression. Otherwise, if pExpr is NULL, then SQLITE_IGNORE
** is treated as SQLITE_DENY. In this case an error is left in pParse.
*/
int sqlite3AuthReadCol(
  Parse *pParse,                  /* The parser context */
  const char *zTab,               /* Table name */
  const char *zCol,               /* Column name */
  int iDb                         /* Index of containing database. */
){
  sqlite3 *db = pParse->db;       /* Database handle */
  char *zDb = db->aDb[iDb].zName; /* Name of attached database */
  int rc;                         /* Auth callback return code */

  rc = db->xAuth(db->pAuthArg, SQLITE_READ, zTab,zCol,zDb,pParse->zAuthContext);
  if( rc==SQLITE_DENY ){
    if( db->nDb>2 || iDb!=0 ){
      sqlite3ErrorMsg(pParse, "access to %s.%s.%s is prohibited",zDb,zTab,zCol);
    }else{
      sqlite3ErrorMsg(pParse, "access to %s.%s is prohibited", zTab, zCol);
    }
    pParse->rc = SQLITE_AUTH;
  }else if( rc!=SQLITE_IGNORE && rc!=SQLITE_OK ){
    sqliteAuthBadReturnCode(pParse);
  }
  return rc;
}

/*
** The pExpr should be a TK_COLUMN expression.  The table referred to
** is in pTabList or else it is the NEW or OLD table of a trigger.  
** Check to see if it is OK to read this particular column.
**
** If the auth function returns SQLITE_IGNORE, change the TK_COLUMN 
** instruction into a TK_NULL.  If the auth function returns SQLITE_DENY,
** then generate an error.
*/
void sqlite3AuthRead(
  Parse *pParse,        /* The parser context */
  Expr *pExpr,          /* The expression to check authorization on */
  Schema *pSchema,      /* The schema of the expression */
  SrcList *pTabList     /* All table that pExpr might refer to */
){
  sqlite3 *db = pParse->db;

  Table *pTab = 0;      /* The table being read */
  const char *zCol;     /* Name of the column of the table */
  int iSrc;             /* Index in pTabList->a[] of table being read */


  int iDb;              /* The index of the database the expression refers to */
  int iCol;             /* Index of column in table */

  if( db->xAuth==0 ) return;

  iDb = sqlite3SchemaToIndex(pParse->db, pSchema);
  if( iDb<0 ){
    /* An attempt to read a column out of a subquery or other
    ** temporary table. */
    return;
  }



  assert( pExpr->op==TK_COLUMN || pExpr->op==TK_TRIGGER );
  if( pExpr->op==TK_TRIGGER ){
    pTab = pParse->pTriggerTab;
  }else{
    assert( pTabList );
    for(iSrc=0; ALWAYS(iSrc<pTabList->nSrc); iSrc++){
      if( pExpr->iTable==pTabList->a[iSrc].iCursor ){
        pTab = pTabList->a[iSrc].pTab;




        break;

      }

    }
  }
  iCol = pExpr->iColumn;
  if( NEVER(pTab==0) ) return;

  if( iCol>=0 ){
    assert( iCol<pTab->nCol );
    zCol = pTab->aCol[iCol].zName;
  }else if( pTab->iPKey>=0 ){
    assert( pTab->iPKey<pTab->nCol );
    zCol = pTab->aCol[pTab->iPKey].zName;
  }else{
    zCol = "ROWID";
  }
  assert( iDb>=0 && iDb<db->nDb );

  if( SQLITE_IGNORE==sqlite3AuthReadCol(pParse, pTab->zName, zCol, iDb) ){


    pExpr->op = TK_NULL;










  }
}

/*
** Do an authorization check using the code and arguments given.  Return
** either SQLITE_OK (zero) or SQLITE_IGNORE or SQLITE_DENY.  If SQLITE_DENY
** is returned, then the error count and error message in pParse are

  }
  rc = db->xAuth(db->pAuthArg, code, zArg1, zArg2, zArg3, pParse->zAuthContext);
  if( rc==SQLITE_DENY ){
    sqlite3ErrorMsg(pParse, "not authorized");
    pParse->rc = SQLITE_AUTH;
  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
    rc = SQLITE_DENY;
    sqliteAuthBadReturnCode(pParse);
  }
  return rc;
}

/*
** Push an authorization context.  After this routine is called, the
** zArg3 argument to authorization callbacks will be zContext until
** popped.  Or if pParse==0, this routine is a no-op.
*/
void sqlite3AuthContextPush(
  Parse *pParse,
  AuthContext *pContext, 
  const char *zContext
){
  assert( pParse );
  pContext->pParse = pParse;

  pContext->zAuthContext = pParse->zAuthContext;
  pParse->zAuthContext = zContext;

}

/*
** Pop an authorization context that was previously pushed
** by sqlite3AuthContextPush
*/
void sqlite3AuthContextPop(AuthContext *pContext){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file implements an object that represents a fixed-length
** bitmap.  Bits are numbered starting with 1.
**
** A bitmap is used to record which pages of a database file have been
** journalled during a transaction, or which pages have the "dont-write"
** property.  Usually only a few pages are meet either condition.
** So the bitmap is usually sparse and has low cardinality.
** But sometimes (for example when during a DROP of a large table) most
** or all of the pages in a database can get journalled.  In those cases, 
** the bitmap becomes dense with high cardinality.  The algorithm needs 
** to handle both cases well.
**
** The size of the bitmap is fixed when the object is created.
**
** All bits are clear when the bitmap is created.  Individual bits
** may be set or cleared one at a time.
**
** Test operations are about 100 times more common that set operations.
** Clear operations are exceedingly rare.  There are usually between
** 5 and 500 set operations per Bitvec object, though the number of sets can
** sometimes grow into tens of thousands or larger.  The size of the
** Bitvec object is the number of pages in the database file at the
** start of a transaction, and is thus usually less than a few thousand,
** but can be as large as 2 billion for a really big database.


*/
#include "sqliteInt.h"

/* Size of the Bitvec structure in bytes. */
#define BITVEC_SZ        512

/* Round the union size down to the nearest pointer boundary, since that's how 
** it will be aligned within the Bitvec struct. */
#define BITVEC_USIZE     (((BITVEC_SZ-(3*sizeof(u32)))/sizeof(Bitvec*))*sizeof(Bitvec*))

/* Type of the array "element" for the bitmap representation. 
** Should be a power of 2, and ideally, evenly divide into BITVEC_USIZE. 
** Setting this to the "natural word" size of your CPU may improve
** performance. */
#define BITVEC_TELEM     u8
/* Size, in bits, of the bitmap element. */
#define BITVEC_SZELEM    8
/* Number of elements in a bitmap array. */
#define BITVEC_NELEM     (BITVEC_USIZE/sizeof(BITVEC_TELEM))
/* Number of bits in the bitmap array. */
#define BITVEC_NBIT      (BITVEC_NELEM*BITVEC_SZELEM)

/* Number of u32 values in hash table. */
#define BITVEC_NINT      (BITVEC_USIZE/sizeof(u32))
/* Maximum number of entries in hash table before 
** sub-dividing and re-hashing. */
#define BITVEC_MXHASH    (BITVEC_NINT/2)
/* Hashing function for the aHash representation.
** Empirical testing showed that the *37 multiplier 
** (an arbitrary prime)in the hash function provided 
** no fewer collisions than the no-op *1. */
#define BITVEC_HASH(X)   (((X)*1)%BITVEC_NINT)

#define BITVEC_NPTR      (BITVEC_USIZE/sizeof(Bitvec *))



/*
** A bitmap is an instance of the following structure.
**
** This bitmap records the existance of zero or more bits
** with values between 1 and iSize, inclusive.
**

** handles up to iDivisor separate values of i.  apSub[0] holds
** values between 1 and iDivisor.  apSub[1] holds values between
** iDivisor+1 and 2*iDivisor.  apSub[N] holds values between
** N*iDivisor+1 and (N+1)*iDivisor.  Each subbitmap is normalized
** to hold deal with values between 1 and iDivisor.
*/
struct Bitvec {
  u32 iSize;      /* Maximum bit index.  Max iSize is 4,294,967,296. */
  u32 nSet;       /* Number of bits that are set - only valid for aHash
                  ** element.  Max is BITVEC_NINT.  For BITVEC_SZ of 512,
                  ** this would be 125. */
  u32 iDivisor;   /* Number of bits handled by each apSub[] entry. */
                  /* Should >=0 for apSub element. */
                  /* Max iDivisor is max(u32) / BITVEC_NPTR + 1.  */
                  /* For a BITVEC_SZ of 512, this would be 34,359,739. */
  union {
    BITVEC_TELEM aBitmap[BITVEC_NELEM];    /* Bitmap representation */
    u32 aHash[BITVEC_NINT];      /* Hash table representation */
    Bitvec *apSub[BITVEC_NPTR];  /* Recursive representation */
  } u;
};

/*
** Create a new bitmap object able to handle bits between 0 and iSize,

** Check to see if the i-th bit is set.  Return true or false.
** If p is NULL (if the bitmap has not been created) or if
** i is out of range, then return false.
*/
int sqlite3BitvecTest(Bitvec *p, u32 i){
  if( p==0 ) return 0;
  if( i>p->iSize || i==0 ) return 0;

  i--;


  while( p->iDivisor ){
    u32 bin = i/p->iDivisor;
    i = i%p->iDivisor;
    p = p->u.apSub[bin];
    if (!p) {
      return 0;
    }
  }
  if( p->iSize<=BITVEC_NBIT ){
    return (p->u.aBitmap[i/BITVEC_SZELEM] & (1<<(i&(BITVEC_SZELEM-1))))!=0;
  } else{
    u32 h = BITVEC_HASH(i++);
    while( p->u.aHash[h] ){
      if( p->u.aHash[h]==i ) return 1;

      h = (h+1) % BITVEC_NINT;
    }
    return 0;
  }
}

/*
** Set the i-th bit.  Return 0 on success and an error code if
** anything goes wrong.
**
** This routine might cause sub-bitmaps to be allocated.  Failing
** to get the memory needed to hold the sub-bitmap is the only
** that can go wrong with an insert, assuming p and i are valid.
**
** The calling function must ensure that p is a valid Bitvec object
** and that the value for "i" is within range of the Bitvec object.
** Otherwise the behavior is undefined.
*/
int sqlite3BitvecSet(Bitvec *p, u32 i){
  u32 h;
  if( p==0 ) return SQLITE_OK;
  assert( i>0 );
  assert( i<=p->iSize );

  i--;



  while((p->iSize > BITVEC_NBIT) && p->iDivisor) {
    u32 bin = i/p->iDivisor;
    i = i%p->iDivisor;
    if( p->u.apSub[bin]==0 ){

      p->u.apSub[bin] = sqlite3BitvecCreate( p->iDivisor );

      if( p->u.apSub[bin]==0 ) return SQLITE_NOMEM;
    }
    p = p->u.apSub[bin];
  }
  if( p->iSize<=BITVEC_NBIT ){
    p->u.aBitmap[i/BITVEC_SZELEM] |= 1 << (i&(BITVEC_SZELEM-1));
    return SQLITE_OK;
  }
  h = BITVEC_HASH(i++);
  /* if there wasn't a hash collision, and this doesn't */
  /* completely fill the hash, then just add it without */
  /* worring about sub-dividing and re-hashing. */
  if( !p->u.aHash[h] ){
    if (p->nSet<(BITVEC_NINT-1)) {
      goto bitvec_set_end;
    } else {
      goto bitvec_set_rehash;
    }
  }
  /* there was a collision, check to see if it's already */
  /* in hash, if not, try to find a spot for it */
  do {
    if( p->u.aHash[h]==i ) return SQLITE_OK;
    h++;
    if( h>=BITVEC_NINT ) h = 0;

  } while( p->u.aHash[h] );
  /* we didn't find it in the hash.  h points to the first */
  /* available free spot. check to see if this is going to */
  /* make our hash too "full".  */
bitvec_set_rehash:
  if( p->nSet>=BITVEC_MXHASH ){
    unsigned int j;
    int rc;
    u32 *aiValues = sqlite3StackAllocRaw(0, sizeof(p->u.aHash));
    if( aiValues==0 ){
      return SQLITE_NOMEM;
    }else{
      memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
      memset(p->u.apSub, 0, sizeof(p->u.apSub));
      p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
      rc = sqlite3BitvecSet(p, i);
      for(j=0; j<BITVEC_NINT; j++){
        if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
      }
      sqlite3StackFree(0, aiValues);
      return rc;
    }
  }
bitvec_set_end:
  p->nSet++;
  p->u.aHash[h] = i;
  return SQLITE_OK;
}

/*
** Clear the i-th bit.
**
** pBuf must be a pointer to at least BITVEC_SZ bytes of temporary storage
** that BitvecClear can use to rebuilt its hash table.
*/
void sqlite3BitvecClear(Bitvec *p, u32 i, void *pBuf){
  if( p==0 ) return;
  assert( i>0 );

  i--;

  while( p->iDivisor ){
    u32 bin = i/p->iDivisor;
    i = i%p->iDivisor;
    p = p->u.apSub[bin];
    if (!p) {
      return;
    }
  }
  if( p->iSize<=BITVEC_NBIT ){
    p->u.aBitmap[i/BITVEC_SZELEM] &= ~(1 << (i&(BITVEC_SZELEM-1)));
  }else{
    unsigned int j;
    u32 *aiValues = pBuf;
    memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
    memset(p->u.aHash, 0, sizeof(p->u.aHash));
    p->nSet = 0;
    for(j=0; j<BITVEC_NINT; j++){
      if( aiValues[j] && aiValues[j]!=(i+1) ){
        u32 h = BITVEC_HASH(aiValues[j]-1);
        p->nSet++;
        while( p->u.aHash[h] ){
          h++;
          if( h>=BITVEC_NINT ) h = 0;
        }
        p->u.aHash[h] = aiValues[j];
      }
    }
  }
}

/*
** Destroy a bitmap object.  Reclaim all memory used.
*/
void sqlite3BitvecDestroy(Bitvec *p){
  if( p==0 ) return;
  if( p->iDivisor ){
    unsigned int i;
    for(i=0; i<BITVEC_NPTR; i++){
      sqlite3BitvecDestroy(p->u.apSub[i]);
    }
  }
  sqlite3_free(p);
}

/*
** Return the value of the iSize parameter specified when Bitvec *p
** was created.
*/
u32 sqlite3BitvecSize(Bitvec *p){
  return p->iSize;
}

#ifndef SQLITE_OMIT_BUILTIN_TEST
/*
** Let V[] be an array of unsigned characters sufficient to hold
** up to N bits.  Let I be an integer between 0 and N.  0<=I<N.
** Then the following macros can be used to set, clear, or test
** individual bits within V.

** If a memory allocation error occurs, return -1.
*/
int sqlite3BitvecBuiltinTest(int sz, int *aOp){
  Bitvec *pBitvec = 0;
  unsigned char *pV = 0;
  int rc = -1;
  int i, nx, pc, op;
  void *pTmpSpace;

  /* Allocate the Bitvec to be tested and a linear array of
  ** bits to act as the reference */
  pBitvec = sqlite3BitvecCreate( sz );
  pV = sqlite3_malloc( (sz+7)/8 + 1 );
  pTmpSpace = sqlite3_malloc(BITVEC_SZ);
  if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
  memset(pV, 0, (sz+7)/8 + 1);

  /* NULL pBitvec tests */
  sqlite3BitvecSet(0, 1);
  sqlite3BitvecClear(0, 1, pTmpSpace);

  /* Run the program */
  pc = 0;
  while( (op = aOp[pc])!=0 ){
    switch( op ){
      case 1:
      case 2:
      case 5: {

    if( (op & 1)!=0 ){
      SETBIT(pV, (i+1));
      if( op!=5 ){
        if( sqlite3BitvecSet(pBitvec, i+1) ) goto bitvec_end;
      }
    }else{
      CLEARBIT(pV, (i+1));
      sqlite3BitvecClear(pBitvec, i+1, pTmpSpace);
    }
  }

  /* Test to make sure the linear array exactly matches the
  ** Bitvec object.  Start with the assumption that they do
  ** match (rc==0).  Change rc to non-zero if a discrepancy
  ** is found.
  */
  rc = sqlite3BitvecTest(0,0) + sqlite3BitvecTest(pBitvec, sz+1)
          + sqlite3BitvecTest(pBitvec, 0)
          + (sqlite3BitvecSize(pBitvec) - sz);
  for(i=1; i<=sz; i++){
    if(  (TESTBIT(pV,i))!=sqlite3BitvecTest(pBitvec,i) ){
      rc = i;
      break;
    }
  }

  /* Free allocated structure */
bitvec_end:
  sqlite3_free(pTmpSpace);
  sqlite3_free(pV);
  sqlite3BitvecDestroy(pBitvec);
  return rc;
}
#endif /* SQLITE_OMIT_BUILTIN_TEST */

/*
** 2007 August 27
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**


** This file contains code used to implement mutexes on Btree objects.
** This code really belongs in btree.c.  But btree.c is getting too
** big and we want to break it down some.  This packaged seemed like
** a good breakout.
*/
#include "btreeInt.h"
#ifndef SQLITE_OMIT_SHARED_CACHE
#if SQLITE_THREADSAFE

/*
** Obtain the BtShared mutex associated with B-Tree handle p. Also,
** set BtShared.db to the database handle associated with p and the
** p->locked boolean to true.
*/
static void lockBtreeMutex(Btree *p){
  assert( p->locked==0 );
  assert( sqlite3_mutex_notheld(p->pBt->mutex) );
  assert( sqlite3_mutex_held(p->db->mutex) );

  sqlite3_mutex_enter(p->pBt->mutex);
  p->pBt->db = p->db;
  p->locked = 1;
}

/*
** Release the BtShared mutex associated with B-Tree handle p and
** clear the p->locked boolean.
*/
static void unlockBtreeMutex(Btree *p){
  assert( p->locked==1 );
  assert( sqlite3_mutex_held(p->pBt->mutex) );
  assert( sqlite3_mutex_held(p->db->mutex) );
  assert( p->db==p->pBt->db );

  sqlite3_mutex_leave(p->pBt->mutex);
  p->locked = 0;
}

/*
** Enter a mutex on the given BTree object.
**
** If the object is not sharable, then no mutex is ever required
** and this routine is a no-op.  The underlying mutex is non-recursive.
** But we keep a reference count in Btree.wantToLock so the behavior

  /* Check for locking consistency */
  assert( !p->locked || p->wantToLock>0 );
  assert( p->sharable || p->wantToLock==0 );

  /* We should already hold a lock on the database connection */
  assert( sqlite3_mutex_held(p->db->mutex) );

  /* Unless the database is sharable and unlocked, then BtShared.db
  ** should already be set correctly. */
  assert( (p->locked==0 && p->sharable) || p->pBt->db==p->db );

  if( !p->sharable ) return;
  p->wantToLock++;
  if( p->locked ) return;


  /* In most cases, we should be able to acquire the lock we
  ** want without having to go throught the ascending lock
  ** procedure that follows.  Just be sure not to block.
  */
  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
    p->pBt->db = p->db;
    p->locked = 1;
    return;
  }

  /* To avoid deadlock, first release all locks with a larger
  ** BtShared address.  Then acquire our lock.  Then reacquire
  ** the other BtShared locks that we used to hold in ascending
  ** order.
  */
  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
    assert( pLater->sharable );
    assert( pLater->pNext==0 || pLater->pNext->pBt>pLater->pBt );
    assert( !pLater->locked || pLater->wantToLock>0 );
    if( pLater->locked ){

      unlockBtreeMutex(pLater);
    }
  }

  lockBtreeMutex(p);
  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
    if( pLater->wantToLock ){

      lockBtreeMutex(pLater);
    }
  }

}

/*
** Exit the recursive mutex on a Btree.
*/
void sqlite3BtreeLeave(Btree *p){
  if( p->sharable ){
    assert( p->wantToLock>0 );
    p->wantToLock--;
    if( p->wantToLock==0 ){


      unlockBtreeMutex(p);
    }
  }
}

#ifndef NDEBUG
/*
** Return true if the BtShared mutex is held on the btree, or if the
** B-Tree is not marked as sharable.


**
** This routine is used only from within assert() statements.
*/
int sqlite3BtreeHoldsMutex(Btree *p){
  assert( p->sharable==0 || p->locked==0 || p->wantToLock>0 );
  assert( p->sharable==0 || p->locked==0 || p->db==p->pBt->db );
  assert( p->sharable==0 || p->locked==0 || sqlite3_mutex_held(p->pBt->mutex) );
  assert( p->sharable==0 || p->locked==0 || sqlite3_mutex_held(p->db->mutex) );

  return (p->sharable==0 || p->locked);

}
#endif


#ifndef SQLITE_OMIT_INCRBLOB
/*
** Enter and leave a mutex on a Btree given a cursor owned by that

*/
void sqlite3BtreeEnterAll(sqlite3 *db){
  int i;
  Btree *p, *pLater;
  assert( sqlite3_mutex_held(db->mutex) );
  for(i=0; i<db->nDb; i++){
    p = db->aDb[i].pBt;
    assert( !p || (p->locked==0 && p->sharable) || p->pBt->db==p->db );
    if( p && p->sharable ){
      p->wantToLock++;
      if( !p->locked ){
        assert( p->wantToLock==1 );
        while( p->pPrev ) p = p->pPrev;
        /* Reason for ALWAYS:  There must be at least on unlocked Btree in
        ** the chain.  Otherwise the !p->locked test above would have failed */
        while( p->locked && ALWAYS(p->pNext) ) p = p->pNext;
        for(pLater = p->pNext; pLater; pLater=pLater->pNext){
          if( pLater->locked ){

            unlockBtreeMutex(pLater);
          }
        }
        while( p ){

          lockBtreeMutex(p);
          p = p->pNext;
        }
      }
    }
  }
}
void sqlite3BtreeLeaveAll(sqlite3 *db){
  int i;
  Btree *p;
  assert( sqlite3_mutex_held(db->mutex) );
  for(i=0; i<db->nDb; i++){
    p = db->aDb[i].pBt;
    if( p && p->sharable ){
      assert( p->wantToLock>0 );
      p->wantToLock--;
      if( p->wantToLock==0 ){


        unlockBtreeMutex(p);
      }
    }
  }
}

#ifndef NDEBUG
/*

  {
    for(i=0; i<pArray->nMutex; i++){
      assert( pArray->aBtree[i]!=pBtree );
    }
  }
#endif
  assert( pArray->nMutex>=0 );
  assert( pArray->nMutex<ArraySize(pArray->aBtree)-1 );
  pBt = pBtree->pBt;
  for(i=0; i<pArray->nMutex; i++){
    assert( pArray->aBtree[i]!=pBtree );
    if( pArray->aBtree[i]->pBt>pBt ){
      for(j=pArray->nMutex; j>i; j--){
        pArray->aBtree[j] = pArray->aBtree[j-1];
      }

    /* Some basic sanity checking */
    assert( i==0 || pArray->aBtree[i-1]->pBt<p->pBt );
    assert( !p->locked || p->wantToLock>0 );

    /* We should already hold a lock on the database connection */
    assert( sqlite3_mutex_held(p->db->mutex) );

    /* The Btree is sharable because only sharable Btrees are entered
    ** into the array in the first place. */
    assert( p->sharable );

    p->wantToLock++;
    if( !p->locked ){

      lockBtreeMutex(p);
    }
  }
}

/*
** Leave the mutex of every btree in the group.
*/
void sqlite3BtreeMutexArrayLeave(BtreeMutexArray *pArray){
  int i;
  for(i=0; i<pArray->nMutex; i++){
    Btree *p = pArray->aBtree[i];
    /* Some basic sanity checking */
    assert( i==0 || pArray->aBtree[i-1]->pBt<p->pBt );
    assert( p->locked );
    assert( p->wantToLock>0 );

    /* We should already hold a lock on the database connection */
    assert( sqlite3_mutex_held(p->db->mutex) );

    p->wantToLock--;
    if( p->wantToLock==0 ){

      unlockBtreeMutex(p);
    }
  }
}

#else
void sqlite3BtreeEnter(Btree *p){
  p->pBt->db = p->db;
}
void sqlite3BtreeEnterAll(sqlite3 *db){
  int i;
  for(i=0; i<db->nDb; i++){
    Btree *p = db->aDb[i].pBt;
    if( p ){
      p->pBt->db = p->db;
    }
  }
}
#endif /* if SQLITE_THREADSAFE */
#endif /* ifndef SQLITE_OMIT_SHARED_CACHE */

/*
** 2004 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************


** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

/*
** The header string that appears at the beginning of every
** SQLite database.
*/
static const char zMagicHeader[] = SQLITE_FILE_HEADER;

/*
** Set this global variable to 1 to enable tracing using the TRACE
** macro.
*/
#if 0
int sqlite3BtreeTrace=1;  /* True to enable tracing */
# define TRACE(X)  if(sqlite3BtreeTrace){printf X;fflush(stdout);}
#else
# define TRACE(X)
#endif

/*
** Extract a 2-byte big-endian integer from an array of unsigned bytes.
** But if the value is zero, make it 65536.
**
** This routine is used to extract the "offset to cell content area" value
** from the header of a btree page.  If the page size is 65536 and the page
** is empty, the offset should be 65536, but the 2-byte value stores zero.
** This routine makes the necessary adjustment to 65536.
*/
#define get2byteNotZero(X)  (((((int)get2byte(X))-1)&0xffff)+1)

#ifndef SQLITE_OMIT_SHARED_CACHE
/*

** A list of BtShared objects that are eligible for participation
** in shared cache.  This variable has file scope during normal builds,
** but the test harness needs to access it so we make it global for 
** test builds.
**
** Access to this variable is protected by SQLITE_MUTEX_STATIC_MASTER.
*/
#ifdef SQLITE_TEST
BtShared *SQLITE_WSD sqlite3SharedCacheList = 0;

#else
static BtShared *SQLITE_WSD sqlite3SharedCacheList = 0;

#endif
#endif /* SQLITE_OMIT_SHARED_CACHE */

#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** Enable or disable the shared pager and schema features.
**
** This routine has no effect on existing database connections.
** The shared cache setting effects only future calls to
** sqlite3_open(), sqlite3_open16(), or sqlite3_open_v2().
*/
int sqlite3_enable_shared_cache(int enable){
  sqlite3GlobalConfig.sharedCacheEnabled = enable;
  return SQLITE_OK;
}
#endif








#ifdef SQLITE_OMIT_SHARED_CACHE
  /*
  ** The functions querySharedCacheTableLock(), setSharedCacheTableLock(),
  ** and clearAllSharedCacheTableLocks()
  ** manipulate entries in the BtShared.pLock linked list used to store
  ** shared-cache table level locks. If the library is compiled with the
  ** shared-cache feature disabled, then there is only ever one user
  ** of each BtShared structure and so this locking is not necessary. 
  ** So define the lock related functions as no-ops.
  */
  #define querySharedCacheTableLock(a,b,c) SQLITE_OK
  #define setSharedCacheTableLock(a,b,c) SQLITE_OK
  #define clearAllSharedCacheTableLocks(a)
  #define downgradeAllSharedCacheTableLocks(a)
  #define hasSharedCacheTableLock(a,b,c,d) 1
  #define hasReadConflicts(a, b) 0
#endif

#ifndef SQLITE_OMIT_SHARED_CACHE

#ifdef SQLITE_DEBUG
/*
**** This function is only used as part of an assert() statement. ***
**
** Check to see if pBtree holds the required locks to read or write to the 
** table with root page iRoot.   Return 1 if it does and 0 if not.
**
** For example, when writing to a table with root-page iRoot via 
** Btree connection pBtree:
**
**    assert( hasSharedCacheTableLock(pBtree, iRoot, 0, WRITE_LOCK) );
**
** When writing to an index that resides in a sharable database, the 
** caller should have first obtained a lock specifying the root page of
** the corresponding table. This makes things a bit more complicated,
** as this module treats each table as a separate structure. To determine
** the table corresponding to the index being written, this
** function has to search through the database schema.
**
** Instead of a lock on the table/index rooted at page iRoot, the caller may
** hold a write-lock on the schema table (root page 1). This is also
** acceptable.
*/
static int hasSharedCacheTableLock(
  Btree *pBtree,         /* Handle that must hold lock */
  Pgno iRoot,            /* Root page of b-tree */
  int isIndex,           /* True if iRoot is the root of an index b-tree */
  int eLockType          /* Required lock type (READ_LOCK or WRITE_LOCK) */
){
  Schema *pSchema = (Schema *)pBtree->pBt->pSchema;
  Pgno iTab = 0;
  BtLock *pLock;

  /* If this database is not shareable, or if the client is reading
  ** and has the read-uncommitted flag set, then no lock is required. 
  ** Return true immediately.
  */
  if( (pBtree->sharable==0)
   || (eLockType==READ_LOCK && (pBtree->db->flags & SQLITE_ReadUncommitted))
  ){
    return 1;
  }

  /* If the client is reading  or writing an index and the schema is
  ** not loaded, then it is too difficult to actually check to see if
  ** the correct locks are held.  So do not bother - just return true.
  ** This case does not come up very often anyhow.
  */
  if( isIndex && (!pSchema || (pSchema->flags&DB_SchemaLoaded)==0) ){
    return 1;
  }

  /* Figure out the root-page that the lock should be held on. For table
  ** b-trees, this is just the root page of the b-tree being read or
  ** written. For index b-trees, it is the root page of the associated
  ** table.  */
  if( isIndex ){
    HashElem *p;
    for(p=sqliteHashFirst(&pSchema->idxHash); p; p=sqliteHashNext(p)){
      Index *pIdx = (Index *)sqliteHashData(p);
      if( pIdx->tnum==(int)iRoot ){
        iTab = pIdx->pTable->tnum;
      }
    }
  }else{
    iTab = iRoot;
  }

  /* Search for the required lock. Either a write-lock on root-page iTab, a 
  ** write-lock on the schema table, or (if the client is reading) a
  ** read-lock on iTab will suffice. Return 1 if any of these are found.  */
  for(pLock=pBtree->pBt->pLock; pLock; pLock=pLock->pNext){
    if( pLock->pBtree==pBtree 
     && (pLock->iTable==iTab || (pLock->eLock==WRITE_LOCK && pLock->iTable==1))
     && pLock->eLock>=eLockType 
    ){
      return 1;
    }
  }

  /* Failed to find the required lock. */
  return 0;
}
#endif /* SQLITE_DEBUG */

#ifdef SQLITE_DEBUG
/*
**** This function may be used as part of assert() statements only. ****
**
** Return true if it would be illegal for pBtree to write into the
** table or index rooted at iRoot because other shared connections are
** simultaneously reading that same table or index.
**
** It is illegal for pBtree to write if some other Btree object that
** shares the same BtShared object is currently reading or writing
** the iRoot table.  Except, if the other Btree object has the
** read-uncommitted flag set, then it is OK for the other object to
** have a read cursor.
**
** For example, before writing to any part of the table or index
** rooted at page iRoot, one should call:
**
**    assert( !hasReadConflicts(pBtree, iRoot) );
*/
static int hasReadConflicts(Btree *pBtree, Pgno iRoot){
  BtCursor *p;
  for(p=pBtree->pBt->pCursor; p; p=p->pNext){
    if( p->pgnoRoot==iRoot 
     && p->pBtree!=pBtree
     && 0==(p->pBtree->db->flags & SQLITE_ReadUncommitted)
    ){
      return 1;
    }
  }
  return 0;
}
#endif    /* #ifdef SQLITE_DEBUG */

/*
** Query to see if Btree handle p may obtain a lock of type eLock 
** (READ_LOCK or WRITE_LOCK) on the table with root-page iTab. Return
** SQLITE_OK if the lock may be obtained (by calling
** setSharedCacheTableLock()), or SQLITE_LOCKED if not.
*/
static int querySharedCacheTableLock(Btree *p, Pgno iTab, u8 eLock){
  BtShared *pBt = p->pBt;
  BtLock *pIter;

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
  assert( p->db!=0 );
  assert( !(p->db->flags&SQLITE_ReadUncommitted)||eLock==WRITE_LOCK||iTab==1 );
  
  /* If requesting a write-lock, then the Btree must have an open write
  ** transaction on this file. And, obviously, for this to be so there 
  ** must be an open write transaction on the file itself.
  */
  assert( eLock==READ_LOCK || (p==pBt->pWriter && p->inTrans==TRANS_WRITE) );
  assert( eLock==READ_LOCK || pBt->inTransaction==TRANS_WRITE );
  
  /* This routine is a no-op if the shared-cache is not enabled */
  if( !p->sharable ){
    return SQLITE_OK;
  }

  /* If some other connection is holding an exclusive lock, the
  ** requested lock may not be obtained.
  */
  if( pBt->pWriter!=p && pBt->isExclusive ){
    sqlite3ConnectionBlocked(p->db, pBt->pWriter->db);
    return SQLITE_LOCKED_SHAREDCACHE;
  }


  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
    /* The condition (pIter->eLock!=eLock) in the following if(...) 

    ** statement is a simplification of:
    **


    **   (eLock==WRITE_LOCK || pIter->eLock==WRITE_LOCK)
    **
    ** since we know that if eLock==WRITE_LOCK, then no other connection

    ** may hold a WRITE_LOCK on any table in this file (since there can
    ** only be a single writer).
    */


    assert( pIter->eLock==READ_LOCK || pIter->eLock==WRITE_LOCK );


    assert( eLock==READ_LOCK || pIter->pBtree==p || pIter->eLock==READ_LOCK);
    if( pIter->pBtree!=p && pIter->iTable==iTab && pIter->eLock!=eLock ){
      sqlite3ConnectionBlocked(p->db, pIter->pBtree->db);
      if( eLock==WRITE_LOCK ){
        assert( p==pBt->pWriter );
        pBt->isPending = 1;
      }
      return SQLITE_LOCKED_SHAREDCACHE;
    }
  }
  return SQLITE_OK;
}
#endif /* !SQLITE_OMIT_SHARED_CACHE */

#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** Add a lock on the table with root-page iTable to the shared-btree used
** by Btree handle p. Parameter eLock must be either READ_LOCK or 
** WRITE_LOCK.
**
** This function assumes the following:
**
**   (a) The specified Btree object p is connected to a sharable
**       database (one with the BtShared.sharable flag set), and
**
**   (b) No other Btree objects hold a lock that conflicts
**       with the requested lock (i.e. querySharedCacheTableLock() has
**       already been called and returned SQLITE_OK).
**
** SQLITE_OK is returned if the lock is added successfully. SQLITE_NOMEM 
** is returned if a malloc attempt fails.
*/
static int setSharedCacheTableLock(Btree *p, Pgno iTable, u8 eLock){
  BtShared *pBt = p->pBt;
  BtLock *pLock = 0;
  BtLock *pIter;

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
  assert( p->db!=0 );





  /* A connection with the read-uncommitted flag set will never try to

  ** obtain a read-lock using this function. The only read-lock obtained
  ** by a connection in read-uncommitted mode is on the sqlite_master 





  ** table, and that lock is obtained in BtreeBeginTrans().  */
  assert( 0==(p->db->flags&SQLITE_ReadUncommitted) || eLock==WRITE_LOCK );





  /* This function should only be called on a sharable b-tree after it 
  ** has been determined that no other b-tree holds a conflicting lock.  */
  assert( p->sharable );
  assert( SQLITE_OK==querySharedCacheTableLock(p, iTable, eLock) );

  /* First search the list for an existing lock on this table. */
  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
    if( pIter->iTable==iTable && pIter->pBtree==p ){
      pLock = pIter;
      break;
    }