jellyfin/Emby.Server.Implementations/Data/BaseSqliteRepository.cs
2019-02-13 12:58:46 +01:00

380 lines
11 KiB
C#

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Threading;
using Microsoft.Extensions.Logging;
using SQLitePCL;
using SQLitePCL.pretty;
namespace Emby.Server.Implementations.Data
{
public abstract class BaseSqliteRepository : IDisposable
{
protected string DbFilePath { get; set; }
protected ReaderWriterLockSlim WriteLock;
protected ILogger Logger { get; private set; }
protected BaseSqliteRepository(ILogger logger)
{
Logger = logger;
WriteLock = new ReaderWriterLockSlim(LockRecursionPolicy.NoRecursion);
}
protected TransactionMode TransactionMode => TransactionMode.Deferred;
protected TransactionMode ReadTransactionMode => TransactionMode.Deferred;
internal static int ThreadSafeMode { get; set; }
static BaseSqliteRepository()
{
SQLite3.EnableSharedCache = false;
int rc = raw.sqlite3_config(raw.SQLITE_CONFIG_MEMSTATUS, 0);
//CheckOk(rc);
rc = raw.sqlite3_config(raw.SQLITE_CONFIG_MULTITHREAD, 1);
//rc = raw.sqlite3_config(raw.SQLITE_CONFIG_SINGLETHREAD, 1);
//rc = raw.sqlite3_config(raw.SQLITE_CONFIG_SERIALIZED, 1);
//CheckOk(rc);
rc = raw.sqlite3_enable_shared_cache(1);
ThreadSafeMode = raw.sqlite3_threadsafe();
}
private static bool _versionLogged;
private string _defaultWal;
protected ManagedConnection _connection;
protected virtual bool EnableSingleConnection => true;
protected ManagedConnection CreateConnection(bool isReadOnly = false)
{
if (_connection != null)
{
return _connection;
}
lock (WriteLock)
{
if (!_versionLogged)
{
_versionLogged = true;
Logger.LogInformation("Sqlite version: " + SQLite3.Version);
Logger.LogInformation("Sqlite compiler options: " + string.Join(",", SQLite3.CompilerOptions.ToArray()));
}
ConnectionFlags connectionFlags;
if (isReadOnly)
{
//Logger.LogInformation("Opening read connection");
//connectionFlags = ConnectionFlags.ReadOnly;
connectionFlags = ConnectionFlags.Create;
connectionFlags |= ConnectionFlags.ReadWrite;
}
else
{
//Logger.LogInformation("Opening write connection");
connectionFlags = ConnectionFlags.Create;
connectionFlags |= ConnectionFlags.ReadWrite;
}
if (EnableSingleConnection)
{
connectionFlags |= ConnectionFlags.PrivateCache;
}
else
{
connectionFlags |= ConnectionFlags.SharedCached;
}
connectionFlags |= ConnectionFlags.NoMutex;
var db = SQLite3.Open(DbFilePath, connectionFlags, null);
try
{
if (string.IsNullOrWhiteSpace(_defaultWal))
{
_defaultWal = db.Query("PRAGMA journal_mode").SelectScalarString().First();
Logger.LogInformation("Default journal_mode for {0} is {1}", DbFilePath, _defaultWal);
}
var queries = new List<string>
{
//"PRAGMA cache size=-10000"
//"PRAGMA read_uncommitted = true",
"PRAGMA synchronous=Normal"
};
if (CacheSize.HasValue)
{
queries.Add("PRAGMA cache_size=" + CacheSize.Value.ToString(CultureInfo.InvariantCulture));
}
if (EnableTempStoreMemory)
{
queries.Add("PRAGMA temp_store = memory");
}
else
{
queries.Add("PRAGMA temp_store = file");
}
foreach (var query in queries)
{
db.Execute(query);
}
}
catch
{
using (db)
{
}
throw;
}
_connection = new ManagedConnection(db, false);
return _connection;
}
}
public IStatement PrepareStatement(ManagedConnection connection, string sql)
{
return connection.PrepareStatement(sql);
}
public IStatement PrepareStatementSafe(ManagedConnection connection, string sql)
{
return connection.PrepareStatement(sql);
}
public IStatement PrepareStatement(IDatabaseConnection connection, string sql)
{
return connection.PrepareStatement(sql);
}
public IStatement PrepareStatementSafe(IDatabaseConnection connection, string sql)
{
return connection.PrepareStatement(sql);
}
public List<IStatement> PrepareAll(IDatabaseConnection connection, IEnumerable<string> sql)
{
return PrepareAllSafe(connection, sql);
}
public List<IStatement> PrepareAllSafe(IDatabaseConnection connection, IEnumerable<string> sql)
{
return sql.Select(connection.PrepareStatement).ToList();
}
protected bool TableExists(ManagedConnection connection, string name)
{
return connection.RunInTransaction(db =>
{
using (var statement = PrepareStatement(db, "select DISTINCT tbl_name from sqlite_master"))
{
foreach (var row in statement.ExecuteQuery())
{
if (string.Equals(name, row.GetString(0), StringComparison.OrdinalIgnoreCase))
{
return true;
}
}
}
return false;
}, ReadTransactionMode);
}
protected void RunDefaultInitialization(ManagedConnection db)
{
var queries = new List<string>
{
"PRAGMA journal_mode=WAL",
"PRAGMA page_size=4096",
"PRAGMA synchronous=Normal"
};
if (EnableTempStoreMemory)
{
queries.AddRange(new List<string>
{
"pragma default_temp_store = memory",
"pragma temp_store = memory"
});
}
else
{
queries.AddRange(new List<string>
{
"pragma temp_store = file"
});
}
db.ExecuteAll(string.Join(";", queries));
Logger.LogInformation("PRAGMA synchronous=" + db.Query("PRAGMA synchronous").SelectScalarString().First());
}
protected virtual bool EnableTempStoreMemory => false;
protected virtual int? CacheSize => null;
private bool _disposed;
protected void CheckDisposed()
{
if (_disposed)
{
throw new ObjectDisposedException(GetType().Name, "Object has been disposed and cannot be accessed.");
}
}
public void Dispose()
{
_disposed = true;
Dispose(true);
}
private readonly object _disposeLock = new object();
/// <summary>
/// Releases unmanaged and - optionally - managed resources.
/// </summary>
/// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
protected virtual void Dispose(bool dispose)
{
if (dispose)
{
DisposeConnection();
}
}
private void DisposeConnection()
{
try
{
lock (_disposeLock)
{
using (WriteLock.Write())
{
if (_connection != null)
{
using (_connection)
{
_connection.Close();
}
_connection = null;
}
CloseConnection();
}
}
}
catch (Exception ex)
{
Logger.LogError(ex, "Error disposing database");
}
}
protected virtual void CloseConnection()
{
}
protected List<string> GetColumnNames(IDatabaseConnection connection, string table)
{
var list = new List<string>();
foreach (var row in connection.Query("PRAGMA table_info(" + table + ")"))
{
if (row[1].SQLiteType != SQLiteType.Null)
{
var name = row[1].ToString();
list.Add(name);
}
}
return list;
}
protected void AddColumn(IDatabaseConnection connection, string table, string columnName, string type, List<string> existingColumnNames)
{
if (existingColumnNames.Contains(columnName, StringComparer.OrdinalIgnoreCase))
{
return;
}
connection.Execute("alter table " + table + " add column " + columnName + " " + type + " NULL");
}
}
public static class ReaderWriterLockSlimExtensions
{
private sealed class ReadLockToken : IDisposable
{
private ReaderWriterLockSlim _sync;
public ReadLockToken(ReaderWriterLockSlim sync)
{
_sync = sync;
sync.EnterReadLock();
}
public void Dispose()
{
if (_sync != null)
{
_sync.ExitReadLock();
_sync = null;
}
}
}
private sealed class WriteLockToken : IDisposable
{
private ReaderWriterLockSlim _sync;
public WriteLockToken(ReaderWriterLockSlim sync)
{
_sync = sync;
sync.EnterWriteLock();
}
public void Dispose()
{
if (_sync != null)
{
_sync.ExitWriteLock();
_sync = null;
}
}
}
public static IDisposable Read(this ReaderWriterLockSlim obj)
{
//if (BaseSqliteRepository.ThreadSafeMode > 0)
//{
// return new DummyToken();
//}
return new WriteLockToken(obj);
}
public static IDisposable Write(this ReaderWriterLockSlim obj)
{
//if (BaseSqliteRepository.ThreadSafeMode > 0)
//{
// return new DummyToken();
//}
return new WriteLockToken(obj);
}
}
}