/// <summary>
/// Indicates whether the specified file is already loaded by a reader or writer.
/// </summary>
/// <param name="name">Infinite file name.</param>
/// <param name="path">Infinite file path.</param>
/// <returns>Returns true if the store is already loaded.</returns>
public static bool IsActive(string name, string path)
{
if (!EventWaitHandle.TryOpenExisting(InfiniteFileWriter.PulseEventName(path, name), out EventWaitHandle eventHandle))
{
return(false);
}
eventHandle.Dispose();
return(true);
}
/// <summary>
/// Indicates whether the specified data store has an active writer.
/// </summary>
/// <param name="storeName">The store name.</param>
/// <param name="storePath">The store path.</param>
/// <returns>Returns true if there is an active data file writer to this store.</returns>
public static bool IsStoreLive(string storeName, string storePath)
{
if (!Mutex.TryOpenExisting(InfiniteFileWriter.ActiveWriterMutexName(storePath, PsiStoreCommon.GetCatalogFileName(storeName)), out Mutex writerActiveMutex))
{
return(false);
}
writerActiveMutex.Dispose();
return(true);
}
public InfiniteFileReader(string path, string fileName, int fileId = 0)
{
this.path = path;
this.fileName = fileName;
this.fileId = fileId;
Mutex pulse;
Mutex.TryOpenExisting(InfiniteFileWriter.PulseEventName(path, fileName), out pulse);
this.writePulse = pulse ?? new Mutex(false);
}
/// <summary>
/// Indicates whether the specified file has an active writer.
/// </summary>
/// <param name="name">Infinite file name.</param>
/// <param name="path">Infinite file path.</param>
/// <returns>Returns true if there is an active writer to this file.</returns>
public static bool IsActive(string name, string path)
{
Mutex writerActiveMutex;
if (!Mutex.TryOpenExisting(InfiniteFileWriter.ActiveWriterMutexName(path, name), out writerActiveMutex))
{
return(false);
}
writerActiveMutex.Dispose();
return(true);
}
public MessageWriter(string name, string path, int extentSize = 0)
{
if (extentSize == 0)
{
extentSize = Environment.Is64BitProcess ? DefaultExtentCapacity64 : DefaultExtentCapacity32;
}
if (path != null)
{
this.fileWriter = new InfiniteFileWriter(path, name, extentSize);
}
else
{
int retentionQueueLength = Environment.Is64BitProcess ? DefaultRetentionQueueLength64 : DefaultRetentionQueueLength32;
this.fileWriter = new InfiniteFileWriter(name, extentSize, retentionQueueLength);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="StoreWriter"/> class.
/// </summary>
/// <param name="name">The name of the application that generated the persisted files, or the root name of the files.</param>
/// <param name="path">The directory in which to create the partition, or null to create a volatile data store.</param>
/// <param name="createSubdirectory">If true, a numbered sub-directory is created for this store.</param>
/// <param name="append">If true, the store is opened in append mode.</param>
public StoreWriter(string name, string path, bool createSubdirectory = true, bool append = false)
{
this.name = name;
this.append = append;
if (path != null)
{
int id = 0;
this.path = System.IO.Path.GetFullPath(path);
if (createSubdirectory)
{
// if the root directory already exists, look for the next available id
if (Directory.Exists(this.path))
{
var existingIds = Directory.EnumerateDirectories(this.path, this.name + ".????")
.Select(d => d.Split('.').Last())
.Where(
n =>
{
int i;
return(int.TryParse(n, out i));
})
.Select(n => int.Parse(n));
id = (existingIds.Count() == 0) ? 0 : existingIds.Max() + 1;
}
this.path = System.IO.Path.Combine(this.path, $"{this.name}.{id:0000}");
}
if (!Directory.Exists(this.path))
{
Directory.CreateDirectory(this.path);
}
}
this.catalogWriter = new InfiniteFileWriter(this.path, StoreCommon.GetCatalogFileName(this.name), CatalogExtentSize, append);
this.pageIndexWriter = new InfiniteFileWriter(this.path, StoreCommon.GetIndexFileName(this.name), IndexExtentSize, append);
this.writer = new MessageWriter(StoreCommon.GetDataFileName(this.name), this.path, append);
// write the first index entry
this.UpdatePageIndex(0, default(Envelope));
}
/// <summary>
/// Indicates whether more data might be added to this file
/// (i.e. the file still has an active writer).
/// </summary>
/// <returns>Returns true if there is an active writer to this file.</returns>
public bool IsMoreDataExpected()
{
return(InfiniteFileWriter.IsActive(this.fileName, this.path));
}
public void Dispose()
{
this.fileWriter.Dispose();
this.fileWriter = null;
}
