/// <summary>Backs up the database, using the specified database connection as the destination.</summary>
/// <param name="destination">The destination database connection.</param>
/// <param name="destinationName">The destination database name (usually <c>"main"</c>).</param>
/// <param name="sourceName">The source database name (usually <c>"main"</c>).</param>
/// <param name="pages">The number of pages to copy, or negative to copy all remaining pages.</param>
/// <param name="callback">The method to invoke between each step of the backup process. This
/// parameter may be <c>null</c> (i.e., no callbacks will be performed).</param>
/// <param name="retryMilliseconds">The number of milliseconds to sleep after encountering a locking error
/// during the backup process. A value less than zero means that no sleep should be performed.</param>
public void BackupDatabase(SQLiteConnection destination, string destinationName, string sourceName, int pages, SQLiteBackupCallback callback, int retryMilliseconds)
{
VerifyNotDisposed();
if (m_connectionState != ConnectionState.Open)
{
throw new InvalidOperationException("Source database is not open.");
}
if (destination == null)
{
throw new ArgumentNullException("destination");
}
if (destination.m_connectionState != ConnectionState.Open)
{
throw new ArgumentException("Destination database is not open.", "destination");
}
if (destinationName == null)
{
throw new ArgumentNullException("destinationName");
}
if (sourceName == null)
{
throw new ArgumentNullException("sourceName");
}
if (pages == 0)
{
throw new ArgumentException("pages must not be 0.", "pages");
}
using (SqliteBackupHandle backup = NativeMethods.sqlite3_backup_init(destination.m_db, ToNullTerminatedUtf8(destinationName), m_db, ToNullTerminatedUtf8(sourceName)))
{
if (backup == null)
{
throw new SQLiteException(NativeMethods.sqlite3_errcode(m_db), m_db);
}
while (true)
{
SQLiteErrorCode error = NativeMethods.sqlite3_backup_step(backup, pages);
if (error == SQLiteErrorCode.Done)
{
break;
}
else if (error == SQLiteErrorCode.Ok || error == SQLiteErrorCode.Busy || error == SQLiteErrorCode.Locked)
{
bool retry = error != SQLiteErrorCode.Ok;
if (callback != null && !callback(this, sourceName, destination, destinationName, pages, NativeMethods.sqlite3_backup_remaining(backup), NativeMethods.sqlite3_backup_pagecount(backup), retry))
{
break;
}
if (retry && retryMilliseconds > 0)
{
Thread.Sleep(retryMilliseconds);
}
}
else
{
throw new SQLiteException(error, m_db);
}
}
}
}
public static extern int sqlite3_backup_remaining(SqliteBackupHandle p);
public static extern int sqlite3_backup_pagecount(SqliteBackupHandle p);
public static extern SQLiteErrorCode sqlite3_backup_step(SqliteBackupHandle p, int nPage);