jellyfin/Emby.Server.Implementations/Data/BaseSqliteRepository.cs
2016-11-27 14:36:56 -05:00

286 lines
7.9 KiB
C#

using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using MediaBrowser.Model.Logging;
using SQLitePCL.pretty;
using System.Linq;
using SQLitePCL;
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 = AllowLockRecursion ?
new ReaderWriterLockSlim(LockRecursionPolicy.SupportsRecursion) :
new ReaderWriterLockSlim(LockRecursionPolicy.NoRecursion);
}
protected virtual bool AllowLockRecursion
{
get { return false; }
}
static BaseSqliteRepository()
{
SQLite3.EnableSharedCache = false;
int rc = raw.sqlite3_config(raw.SQLITE_CONFIG_MEMSTATUS, 0);
//CheckOk(rc);
}
private static bool _versionLogged;
private string _defaultWal;
protected SQLiteDatabaseConnection CreateConnection(bool isReadOnly = false)
{
if (!_versionLogged)
{
_versionLogged = true;
Logger.Info("Sqlite version: " + SQLite3.Version);
Logger.Info("Sqlite compiler options: " + string.Join(",", SQLite3.CompilerOptions.ToArray()));
}
ConnectionFlags connectionFlags;
if (isReadOnly)
{
//Logger.Info("Opening read connection");
}
else
{
//Logger.Info("Opening write connection");
}
isReadOnly = false;
if (isReadOnly)
{
connectionFlags = ConnectionFlags.ReadOnly;
//connectionFlags = ConnectionFlags.Create;
//connectionFlags |= ConnectionFlags.ReadWrite;
}
else
{
connectionFlags = ConnectionFlags.Create;
connectionFlags |= ConnectionFlags.ReadWrite;
}
connectionFlags |= ConnectionFlags.SharedCached;
connectionFlags |= ConnectionFlags.NoMutex;
var db = SQLite3.Open(DbFilePath, connectionFlags, null);
if (string.IsNullOrWhiteSpace(_defaultWal))
{
_defaultWal = db.Query("PRAGMA journal_mode").SelectScalarString().First();
}
var queries = new List<string>
{
//"PRAGMA cache size=-10000"
};
if (EnableTempStoreMemory)
{
queries.Add("PRAGMA temp_store = memory");
}
//var cacheSize = CacheSize;
//if (cacheSize.HasValue)
//{
//}
////foreach (var query in queries)
////{
//// db.Execute(query);
////}
//Logger.Info("synchronous: " + db.Query("PRAGMA synchronous").SelectScalarString().First());
//Logger.Info("temp_store: " + db.Query("PRAGMA temp_store").SelectScalarString().First());
if (!string.Equals(_defaultWal, "wal", StringComparison.OrdinalIgnoreCase))
{
queries.Add("PRAGMA journal_mode=WAL");
using (WriteLock.Write())
{
db.ExecuteAll(string.Join(";", queries.ToArray()));
}
}
else if (queries.Count > 0)
{
db.ExecuteAll(string.Join(";", queries.ToArray()));
}
return db;
}
protected virtual bool EnableTempStoreMemory
{
get
{
return false;
}
}
protected virtual int? CacheSize
{
get
{
return null;
}
}
internal static void CheckOk(int rc)
{
string msg = "";
if (raw.SQLITE_OK != rc)
{
throw CreateException((ErrorCode)rc, msg);
}
}
internal static Exception CreateException(ErrorCode rc, string msg)
{
var exp = new Exception(msg);
return exp;
}
private bool _disposed;
protected void CheckDisposed()
{
if (_disposed)
{
throw new ObjectDisposedException(GetType().Name + " has been disposed and cannot be accessed.");
}
}
public void Dispose()
{
_disposed = true;
Dispose(true);
GC.SuppressFinalize(this);
}
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)
{
try
{
lock (_disposeLock)
{
using (WriteLock.Write())
{
CloseConnection();
}
}
}
catch (Exception ex)
{
Logger.ErrorException("Error disposing database", ex);
}
}
}
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)
{
return new ReadLockToken(obj);
}
public static IDisposable Write(this ReaderWriterLockSlim obj)
{
return new WriteLockToken(obj);
}
}
}