System.Data.SQLite
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Overview
SHA1 Hash:6eac31ab88f55b09f9ce52889973ddd8e8c25e63
Date: 2012-03-24 10:05:13
User: mistachkin
Comment:Start of work on ticket [c71846ed57], supporting the SQLite online backup API.
Tags And Properties
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to System.Data.SQLite/SQLite3.cs

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    internal override int SetLogCallback(SQLiteLogCallback func)
    {
        int rc = UnsafeNativeMethods.sqlite3_config(
            (int)SQLiteConfigOpsEnum.SQLITE_CONFIG_LOG, func, (IntPtr)0);

        return rc;
    }




















































































































































    /// <summary>
    /// Determines if the SQLite core library has been initialized for the
    /// current process.
    /// </summary>
    /// <returns>
    /// A boolean indicating whether or not the SQLite core library has been







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    internal override int SetLogCallback(SQLiteLogCallback func)
    {
        int rc = UnsafeNativeMethods.sqlite3_config(
            (int)SQLiteConfigOpsEnum.SQLITE_CONFIG_LOG, func, (IntPtr)0);

        return rc;
    }

    ///////////////////////////////////////////////////////////////////////////////////////////////

    /// <summary>
    /// Creates a new SQLite backup object based on the provided destination
    /// database connection.  The source database connection is the one
    /// associated with this object.  The source and destination database
    /// connections cannot be the same.
    /// </summary>
    /// <param name="destCnn">The destination database connection handle.</param>
    /// <param name="destName">The destination database name.</param>
    /// <param name="sourceName">The source database name.</param>
    /// <returns>The newly created backup object.</returns>
    internal override SQLiteBackup InitializeBackup(
        SQLiteConnectionHandle destCnn,
        string destName,
        string sourceName
        )
    {
        if (destCnn == null)
            throw new ArgumentNullException("destCnn");

        if (destName == null)
            throw new ArgumentNullException("destName");

        if (sourceName == null)
            throw new ArgumentNullException("sourceName");

        byte[] zDestName = ToUTF8(destName);
        byte[] zSourceName = ToUTF8(sourceName);

        IntPtr backup = UnsafeNativeMethods.sqlite3_backup_init(
            destCnn, zDestName, _sql, zSourceName);

        if (backup == IntPtr.Zero)
            throw new SQLiteException(ResultCode(), SQLiteLastError());

        return new SQLiteBackup(this, backup, destCnn, zDestName, _sql,
            zSourceName);
    }

    /// <summary>
    /// Copies up to N pages from the source database to the destination
    /// database associated with the specified backup object.
    /// </summary>
    /// <param name="backup">The backup object to use.</param>
    /// <param name="nPage">
    /// The number of pages to copy, negative to copy all remaining pages.
    /// </param>
    /// <returns>
    /// True if there are more pages to be copied, false otherwise.
    /// </returns>
    internal override bool StepBackup(
        SQLiteBackup backup,
        int nPage
        )
    {
        if (backup == null)
            throw new ArgumentNullException("backup");

        SQLiteBackupHandle handle = backup._sqlite_backup;

        if (handle == null)
            throw new InvalidOperationException(
                "Backup object has an invalid handle.");

        int n = UnsafeNativeMethods.sqlite3_backup_step(handle, nPage);
        backup._stepResult = n; /* NOTE: Save for use by FinishBackup. */

        if (n == (int)SQLiteErrorCode.Ok)
            return true;
        else if (n == (int)SQLiteErrorCode.Done)
            return false;
        else
            throw new SQLiteException(n, SQLiteLastError());
    }

    /// <summary>
    /// Returns the number of pages remaining to be copied from the source
    /// database to the destination database associated with the specified
    /// backup object.
    /// </summary>
    /// <param name="backup">The backup object to check.</param>
    /// <returns>The number of pages remaining to be copied.</returns>
    internal override int RemainingBackup(
        SQLiteBackup backup
        )
    {
        if (backup == null)
            throw new ArgumentNullException("backup");

        SQLiteBackupHandle handle = backup._sqlite_backup;

        if (handle == null)
            throw new InvalidOperationException(
                "Backup object has an invalid handle.");

        return UnsafeNativeMethods.sqlite3_backup_remaining(handle);
    }

    /// <summary>
    /// Returns the total number of pages in the source database associated
    /// with the specified backup object.
    /// </summary>
    /// <param name="backup">The backup object to check.</param>
    /// <returns>The total number of pages in the source database.</returns>
    internal override int PageCountBackup(
        SQLiteBackup backup
        )
    {
        if (backup == null)
            throw new ArgumentNullException("backup");

        SQLiteBackupHandle handle = backup._sqlite_backup;

        if (handle == null)
            throw new InvalidOperationException(
                "Backup object has an invalid handle.");

        return UnsafeNativeMethods.sqlite3_backup_pagecount(handle);
    }

    /// <summary>
    /// Destroys the backup object, rolling back any backup that may be in
    /// progess.
    /// </summary>
    /// <param name="backup">The backup object to destroy.</param>
    internal override void FinishBackup(
        SQLiteBackup backup
        )
    {
        if (backup == null)
            throw new ArgumentNullException("backup");

        SQLiteBackupHandle handle = backup._sqlite_backup;

        if (handle == null)
            throw new InvalidOperationException(
                "Backup object has an invalid handle.");

        int n = UnsafeNativeMethods.sqlite3_backup_finish(handle);

        if (n > 0 && n != backup._stepResult)
            throw new SQLiteException(n, SQLiteLastError());
    }

    ///////////////////////////////////////////////////////////////////////////////////////////////

    /// <summary>
    /// Determines if the SQLite core library has been initialized for the
    /// current process.
    /// </summary>
    /// <returns>
    /// A boolean indicating whether or not the SQLite core library has been

Added System.Data.SQLite/SQLiteBackup.cs











































































































































































































































































































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/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace System.Data.SQLite
{
    using System;

    /// <summary>
    /// Represents a single SQL backup in SQLite.
    /// </summary>
    internal sealed class SQLiteBackup : IDisposable
    {
        /// <summary>
        /// The underlying SQLite object this backup is bound to.
        /// </summary>
        internal SQLiteBase _sql;

        /// <summary>
        /// The actual backup handle.
        /// </summary>
        internal SQLiteBackupHandle _sqlite_backup;

        /// <summary>
        /// The destination database for the backup.
        /// </summary>
        internal IntPtr _destDb;

        /// <summary>
        /// The destination database name for the backup.
        /// </summary>
        internal byte[] _zDestName;

        /// <summary>
        /// The source database for the backup.
        /// </summary>
        internal IntPtr _sourceDb;

        /// <summary>
        /// The source database name for the backup.
        /// </summary>
        internal byte[] _zSourceName;

        /// <summary>
        /// The last result from the StepBackup method of the SQLite3 class.
        /// This is used to determine if the call to the FinishBackup method of
        /// the SQLite3 class should throw an exception when it receives a non-Ok
        /// return code from the core SQLite library.
        /// </summary>
        internal int _stepResult;

        /// <summary>
        /// Initializes the backup.
        /// </summary>
        /// <param name="sqlbase">The base SQLite object.</param>
        /// <param name="backup">The backup handle.</param>
        /// <param name="destDb">The destination database for the backup.</param>
        /// <param name="zDestName">The destination database name for the backup.</param>
        /// <param name="sourceDb">The source database for the backup.</param>
        /// <param name="zSourceName">The source database name for the backup.</param>
        internal SQLiteBackup(
            SQLiteBase sqlbase,
            SQLiteBackupHandle backup,
            IntPtr destDb,
            byte[] zDestName,
            IntPtr sourceDb,
            byte[] zSourceName
            )
        {
            _sql = sqlbase;
            _sqlite_backup = backup;
            _destDb = destDb;
            _zDestName = zDestName;
            _sourceDb = sourceDb;
            _zSourceName = zSourceName;
        }

        ///////////////////////////////////////////////////////////////////////////////////////////////

        #region IDisposable Members
        /// <summary>
        /// Disposes and finalizes the backup.
        /// </summary>
        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////////////////////////////

        #region IDisposable "Pattern" Members
        private bool disposed;
        private void CheckDisposed() /* throw */
        {
#if THROW_ON_DISPOSED
        if (disposed)
            throw new ObjectDisposedException(typeof(SQLiteBackup).Name);
#endif
        }

        ///////////////////////////////////////////////////////////////////////////////////////////////

        private void Dispose(bool disposing)
        {
            if (!disposed)
            {
                if (disposing)
                {
                    ////////////////////////////////////
                    // dispose managed resources here...
                    ////////////////////////////////////

                    if (_sqlite_backup != null)
                    {
                        _sqlite_backup.Dispose();
                        _sqlite_backup = null;
                    }

                    _zSourceName = null;
                    _sourceDb = IntPtr.Zero;
                    _zDestName = null;
                    _destDb = IntPtr.Zero;
                    _sql = null;
                }

                //////////////////////////////////////
                // release unmanaged resources here...
                //////////////////////////////////////

                disposed = true;
            }
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////////////////////////////

        #region Destructor
        ~SQLiteBackup()
        {
            Dispose(false);
        }
        #endregion
    }
}

Changes to System.Data.SQLite/SQLiteBase.cs

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    internal abstract bool AutoCommit
    {
      get;
    }

    internal abstract int FileControl(string zDbName, int op, IntPtr pArg);




















































    ///////////////////////////////////////////////////////////////////////////////////////////////

    #region IDisposable Members
    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
................................................................................
#if !SQLITE_STANDARD
      int len;
      return UTF8ToString(UnsafeNativeMethods.sqlite3_errmsg_interop(db, out len), len);
#else
      return UTF8ToString(UnsafeNativeMethods.sqlite3_errmsg(db), -1);
#endif
    }










    internal static void FinalizeStatement(SQLiteStatementHandle stmt)
    {
      lock (_lock)
      {
#if !SQLITE_STANDARD
        int n = UnsafeNativeMethods.sqlite3_finalize_interop(stmt);







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    internal abstract bool AutoCommit
    {
      get;
    }

    internal abstract int FileControl(string zDbName, int op, IntPtr pArg);

    /// <summary>
    /// Creates a new SQLite backup object based on the provided destination
    /// database connection.  The source database connection is the one
    /// associated with this object.  The source and destination database
    /// connections cannot be the same.
    /// </summary>
    /// <param name="destCnn">The destination database connection handle.</param>
    /// <param name="destName">The destination database name.</param>
    /// <param name="sourceName">The source database name.</param>
    /// <returns>The newly created backup object.</returns>
    internal abstract SQLiteBackup InitializeBackup(
        SQLiteConnectionHandle destCnn, string destName,
        string sourceName);

    /// <summary>
    /// Copies up to N pages from the source database to the destination
    /// database associated with the specified backup object.
    /// </summary>
    /// <param name="backup">The backup object to use.</param>
    /// <param name="nPage">
    /// The number of pages to copy, negative to copy all remaining pages.
    /// </param>
    /// <returns>
    /// True if there are more pages to be copied, false otherwise.
    /// </returns>
    internal abstract bool StepBackup(SQLiteBackup backup, int nPage);

    /// <summary>
    /// Returns the number of pages remaining to be copied from the source
    /// database to the destination database associated with the specified
    /// backup object.
    /// </summary>
    /// <param name="backup">The backup object to check.</param>
    /// <returns>The number of pages remaining to be copied.</returns>
    internal abstract int RemainingBackup(SQLiteBackup backup);

    /// <summary>
    /// Returns the total number of pages in the source database associated
    /// with the specified backup object.
    /// </summary>
    /// <param name="backup">The backup object to check.</param>
    /// <returns>The total number of pages in the source database.</returns>
    internal abstract int PageCountBackup(SQLiteBackup backup);

    /// <summary>
    /// Destroys the backup object, rolling back any backup that may be in
    /// progess.
    /// </summary>
    /// <param name="backup">The backup object to destroy.</param>
    internal abstract void FinishBackup(SQLiteBackup backup);

    ///////////////////////////////////////////////////////////////////////////////////////////////

    #region IDisposable Members
    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
................................................................................
#if !SQLITE_STANDARD
      int len;
      return UTF8ToString(UnsafeNativeMethods.sqlite3_errmsg_interop(db, out len), len);
#else
      return UTF8ToString(UnsafeNativeMethods.sqlite3_errmsg(db), -1);
#endif
    }

    internal static void FinishBackup(SQLiteBackupHandle backup)
    {
        lock (_lock)
        {
            int n = UnsafeNativeMethods.sqlite3_backup_finish(backup);
            if (n > 0) throw new SQLiteException(n, null);
        }
    }

    internal static void FinalizeStatement(SQLiteStatementHandle stmt)
    {
      lock (_lock)
      {
#if !SQLITE_STANDARD
        int n = UnsafeNativeMethods.sqlite3_finalize_interop(stmt);

Changes to System.Data.SQLite/System.Data.SQLite.Files.targets

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  ******************************************************************************
  -->

  <ItemGroup>
    <Compile Include="AssemblyInfo.cs" />
    <Compile Include="SQLite3.cs" />
    <Compile Include="SQLite3_UTF16.cs" />

    <Compile Include="SQLiteBase.cs" />
    <Compile Include="SQLiteCommand.cs">
      <SubType>Component</SubType>
    </Compile>
    <Compile Include="SQLiteCommandBuilder.cs">
      <SubType>Component</SubType>
    </Compile>







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  ******************************************************************************
  -->

  <ItemGroup>
    <Compile Include="AssemblyInfo.cs" />
    <Compile Include="SQLite3.cs" />
    <Compile Include="SQLite3_UTF16.cs" />
    <Compile Include="SQLiteBackup.cs" />
    <Compile Include="SQLiteBase.cs" />
    <Compile Include="SQLiteCommand.cs">
      <SubType>Component</SubType>
    </Compile>
    <Compile Include="SQLiteCommandBuilder.cs">
      <SubType>Component</SubType>
    </Compile>

Changes to System.Data.SQLite/UnsafeNativeMethods.cs

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#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern int sqlite3_file_control(IntPtr db, byte[] zDbName, int op, IntPtr pArg);



































    #endregion
  }

#if PLATFORM_COMPACTFRAMEWORK
  internal abstract class CriticalHandle : IDisposable
  {
    private bool _isClosed;
................................................................................
    }

    public override bool IsInvalid
    {
      get { return (handle == IntPtr.Zero); }
    }
  }
}



















































































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#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern int sqlite3_file_control(IntPtr db, byte[] zDbName, int op, IntPtr pArg);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern IntPtr sqlite3_backup_init(IntPtr destDb, byte[] zDestName, IntPtr sourceDb, byte[] zSourceName);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern int sqlite3_backup_step(IntPtr backup, int nPage);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern int sqlite3_backup_finish(IntPtr backup);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern int sqlite3_backup_remaining(IntPtr backup);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern int sqlite3_backup_pagecount(IntPtr backup);
    #endregion
  }

#if PLATFORM_COMPACTFRAMEWORK
  internal abstract class CriticalHandle : IDisposable
  {
    private bool _isClosed;
................................................................................
    }

    public override bool IsInvalid
    {
      get { return (handle == IntPtr.Zero); }
    }
  }

  // Provides finalization support for unmanaged SQLite backup objects.
  internal class SQLiteBackupHandle : CriticalHandle
  {
      public static implicit operator IntPtr(SQLiteBackupHandle backup)
      {
          return (backup != null) ? backup.handle : IntPtr.Zero;
      }

      public static implicit operator SQLiteBackupHandle(IntPtr backup)
      {
          return new SQLiteBackupHandle(backup);
      }

      private SQLiteBackupHandle(IntPtr backup)
          : this()
      {
          SetHandle(backup);
      }

      internal SQLiteBackupHandle()
          : base(IntPtr.Zero)
      {
      }

      protected override bool ReleaseHandle()
      {
          try
          {
              SQLiteBase.FinishBackup(this);

#if DEBUG && !NET_COMPACT_20
              try
              {
                  Trace.WriteLine(String.Format(
                      "FinishBackup: {0}", handle));
              }
              catch
              {
              }
#endif

#if DEBUG
              return true;
#endif
          }
#if DEBUG && !NET_COMPACT_20
          catch (SQLiteException e)
#else
          catch (SQLiteException)
#endif
          {
#if DEBUG && !NET_COMPACT_20
              try
              {
                  Trace.WriteLine(String.Format(
                      "FinishBackup: {0}, exception: {1}",
                      handle, e));
              }
              catch
              {
              }
#endif
          }
#if DEBUG
          return false;
#else
          return true;
#endif
      }

      public override bool IsInvalid
      {
          get { return (handle == IntPtr.Zero); }
      }
  }
}