/mcs/class/System.Core/System.IO.MemoryMappedFiles/MemoryMappedFile.cs
C# | 393 lines | 278 code | 67 blank | 48 comment | 52 complexity | 7d3f6b3f6b1012961df218bbe458e761 MD5 | raw file
- //
- // MemoryMappedFile.cs
- //
- // Authors:
- // Zoltan Varga (vargaz@gmail.com)
- //
- // Copyright (C) 2009, Novell, Inc (http://www.novell.com)
- //
- // Permission is hereby granted, free of charge, to any person obtaining
- // a copy of this software and associated documentation files (the
- // "Software"), to deal in the Software without restriction, including
- // without limitation the rights to use, copy, modify, merge, publish,
- // distribute, sublicense, and/or sell copies of the Software, and to
- // permit persons to whom the Software is furnished to do so, subject to
- // the following conditions:
- //
- // The above copyright notice and this permission notice shall be
- // included in all copies or substantial portions of the Software.
- //
- // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
- // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- //
- #if NET_4_0
- using System;
- using System.IO;
- using System.Collections.Generic;
- using Microsoft.Win32.SafeHandles;
- using Mono.Unix.Native;
- using Mono.Unix;
- using System.Runtime.InteropServices;
- namespace System.IO.MemoryMappedFiles
- {
- public class MemoryMappedFile : IDisposable {
- MemoryMappedFileAccess fileAccess;
- string name;
- long fileCapacity;
- //
- // We allow the use of either the FileStream/keepOpen combo
- // or a Unix file descriptor. This way we avoid the dependency on
- // Mono's io-layer having the Unix file descriptors mapped to
- // the same io-layer handle
- //
- FileStream stream;
- bool keepOpen;
- int unix_fd;
- public static MemoryMappedFile CreateFromFile (string path)
- {
- return CreateFromFile (path, FileMode.Open, null, 0, MemoryMappedFileAccess.ReadWrite);
- }
- public static MemoryMappedFile CreateFromFile (string path, FileMode mode)
- {
- return CreateFromFile (path, mode, null, 0, MemoryMappedFileAccess.ReadWrite);
- }
- public static MemoryMappedFile CreateFromFile (string path, FileMode mode, string mapName)
- {
- return CreateFromFile (path, mode, mapName, 0, MemoryMappedFileAccess.ReadWrite);
- }
- public static MemoryMappedFile CreateFromFile (string path, FileMode mode, string mapName, long capacity)
- {
- return CreateFromFile (path, mode, mapName, capacity, MemoryMappedFileAccess.ReadWrite);
- }
- //
- // Turns the FileMode into the first half of open(2) flags
- //
- static OpenFlags ToUnixMode (FileMode mode)
- {
- switch (mode){
- case FileMode.CreateNew:
- return OpenFlags.O_CREAT | OpenFlags.O_EXCL;
-
- case FileMode.Create:
- return OpenFlags.O_CREAT | OpenFlags.O_TRUNC;
-
- case FileMode.OpenOrCreate:
- return OpenFlags.O_CREAT;
-
- case FileMode.Truncate:
- return OpenFlags.O_TRUNC;
-
- case FileMode.Append:
- return OpenFlags.O_APPEND;
- default:
- case FileMode.Open:
- return 0;
- }
- }
- //
- // Turns the MemoryMappedFileAccess into the second half of open(2) flags
- //
- static OpenFlags ToUnixMode (MemoryMappedFileAccess access)
- {
- switch (access){
- case MemoryMappedFileAccess.CopyOnWrite:
- case MemoryMappedFileAccess.ReadWriteExecute:
- case MemoryMappedFileAccess.ReadWrite:
- return OpenFlags.O_RDWR;
-
- case MemoryMappedFileAccess.Write:
- return OpenFlags.O_WRONLY;
- case MemoryMappedFileAccess.ReadExecute:
- case MemoryMappedFileAccess.Read:
- default:
- return OpenFlags.O_RDONLY;
- }
- }
- public static MemoryMappedFile CreateFromFile (string path, FileMode mode, string mapName, long capacity, MemoryMappedFileAccess access)
- {
- if (path == null)
- throw new ArgumentNullException ("path");
- if (path.Length == 0)
- throw new ArgumentException ("path");
- if (mapName != null && mapName.Length == 0)
- throw new ArgumentException ("mapName");
- int fd;
- if (MonoUtil.IsUnix){
- Stat buf;
- if (Syscall.stat (path, out buf) == -1)
- UnixMarshal.ThrowExceptionForLastError ();
- if ((capacity == 0 && buf.st_size == 0) || (capacity > buf.st_size))
- throw new ArgumentException ("capacity");
-
- fd = Syscall.open (path, ToUnixMode (mode) | ToUnixMode (access), FilePermissions.DEFFILEMODE);
- if (fd == -1)
- UnixMarshal.ThrowExceptionForLastError ();
- } else
- throw new NotImplementedException ();
-
- return new MemoryMappedFile () {
- unix_fd = fd,
- fileAccess = access,
- name = mapName,
- fileCapacity = capacity
- };
- }
- static void ConfigureUnixFD (IntPtr handle, HandleInheritability h)
- {
- // TODO: Mono.Posix is lacking O_CLOEXEC definitions for fcntl.
- }
- [DllImport("kernel32.dll", SetLastError = true)]
- static extern bool SetHandleInformation (IntPtr hObject, int dwMask, int dwFlags);
- static void ConfigureWindowsFD (IntPtr handle, HandleInheritability h)
- {
- SetHandleInformation (handle, 1 /* FLAG_INHERIT */, h == HandleInheritability.None ? 0 : 1);
- }
- [MonoLimitation ("memoryMappedFileSecurity is currently ignored")]
- public static MemoryMappedFile CreateFromFile (FileStream fileStream, string mapName, long capacity, MemoryMappedFileAccess access,
- MemoryMappedFileSecurity memoryMappedFileSecurity, HandleInheritability inheritability,
- bool leaveOpen)
- {
- if (fileStream == null)
- throw new ArgumentNullException ("fileStream");
- if (mapName != null && mapName.Length == 0)
- throw new ArgumentException ("mapName");
- if ((capacity == 0 && fileStream.Length == 0) || (capacity > fileStream.Length))
- throw new ArgumentException ("capacity");
- if (MonoUtil.IsUnix)
- ConfigureUnixFD (fileStream.Handle, inheritability);
- else
- ConfigureWindowsFD (fileStream.Handle, inheritability);
-
- return new MemoryMappedFile () {
- stream = fileStream,
- fileAccess = access,
- name = mapName,
- fileCapacity = capacity,
- keepOpen = leaveOpen
- };
- }
- [MonoLimitation ("CreateNew requires that mapName be a file name on Unix")]
- public static MemoryMappedFile CreateNew (string mapName, long capacity)
- {
- return CreateNew (mapName, capacity, MemoryMappedFileAccess.ReadWrite, MemoryMappedFileOptions.DelayAllocatePages, null, 0);
- }
- [MonoLimitation ("CreateNew requires that mapName be a file name on Unix")]
- public static MemoryMappedFile CreateNew (string mapName, long capacity, MemoryMappedFileAccess access)
- {
- return CreateNew (mapName, capacity, access, MemoryMappedFileOptions.DelayAllocatePages, null, 0);
- }
- [MonoLimitation ("CreateNew requires that mapName be a file name on Unix; options and memoryMappedFileSecurity are ignored")]
- public static MemoryMappedFile CreateNew (string mapName, long capacity, MemoryMappedFileAccess access,
- MemoryMappedFileOptions options, MemoryMappedFileSecurity memoryMappedFileSecurity,
- HandleInheritability handleInheritability)
- {
- return CreateFromFile (mapName, FileMode.CreateNew, mapName, capacity, access);
- }
- [MonoLimitation ("CreateOrOpen requires that mapName be a file name on Unix")]
- public static MemoryMappedFile CreateOrOpen (string mapName, long capacity)
- {
- return CreateOrOpen (mapName, capacity, MemoryMappedFileAccess.ReadWrite);
- }
- [MonoLimitation ("CreateOrOpen requires that mapName be a file name on Unix")]
- public static MemoryMappedFile CreateOrOpen (string mapName, long capacity, MemoryMappedFileAccess access)
- {
- return CreateFromFile (mapName, FileMode.OpenOrCreate, mapName, capacity, access);
- }
- [MonoTODO]
- public static MemoryMappedFile CreateOrOpen (string mapName, long capacity, MemoryMappedFileAccess access, MemoryMappedFileOptions options, MemoryMappedFileSecurity memoryMappedFileSecurity, HandleInheritability handleInheritability)
- {
- throw new NotImplementedException ();
- }
- [MonoTODO]
- public static MemoryMappedFile OpenExisting (string mapName)
- {
- throw new NotImplementedException ();
- }
- [MonoTODO]
- public static MemoryMappedFile OpenExisting (string mapName, MemoryMappedFileRights desiredAccessRights)
- {
- throw new NotImplementedException ();
- }
- [MonoTODO]
- public static MemoryMappedFile OpenExisting (string mapName, MemoryMappedFileRights desiredAccessRights, HandleInheritability inheritability)
- {
- throw new NotImplementedException ();
- }
- public MemoryMappedViewStream CreateViewStream ()
- {
- return CreateViewStream (0, 0);
- }
- public MemoryMappedViewStream CreateViewStream (long offset, long size)
- {
- return CreateViewStream (offset, size, MemoryMappedFileAccess.ReadWrite);
- }
- public MemoryMappedViewStream CreateViewStream (long offset, long size, MemoryMappedFileAccess access)
- {
- return new MemoryMappedViewStream (stream != null ? (int)stream.Handle : unix_fd, offset, size, access);
- }
- public MemoryMappedViewAccessor CreateViewAccessor ()
- {
- return CreateViewAccessor (0, 0);
- }
- public MemoryMappedViewAccessor CreateViewAccessor (long offset, long size)
- {
- return CreateViewAccessor (offset, size, MemoryMappedFileAccess.ReadWrite);
- }
- public MemoryMappedViewAccessor CreateViewAccessor (long offset, long size, MemoryMappedFileAccess access)
- {
- int file_handle = stream != null ? (int) stream.Handle : unix_fd;
-
- return new MemoryMappedViewAccessor (file_handle, offset, size, access);
- }
- MemoryMappedFile ()
- {
- }
- public void Dispose ()
- {
- Dispose (true);
- }
- protected virtual void Dispose (bool disposing)
- {
- if (disposing){
- if (stream != null){
- if (keepOpen == false)
- stream.Close ();
- unix_fd = -1;
- }
- if (unix_fd != -1)
- Syscall.close (unix_fd);
- unix_fd = -1;
- stream = null;
- }
- }
- [MonoTODO]
- public MemoryMappedFileSecurity GetAccessControl ()
- {
- throw new NotImplementedException ();
- }
- [MonoTODO]
- public void SetAccessControl (MemoryMappedFileSecurity memoryMappedFileSecurity)
- {
- throw new NotImplementedException ();
- }
- [MonoTODO]
- public SafeMemoryMappedFileHandle SafeMemoryMappedFileHandle {
- get {
- throw new NotImplementedException ();
- }
- }
- static int pagesize;
- static MmapProts ToUnixProts (MemoryMappedFileAccess access)
- {
- switch (access){
- case MemoryMappedFileAccess.ReadWrite:
- return MmapProts.PROT_WRITE | MmapProts.PROT_READ;
-
- case MemoryMappedFileAccess.Write:
- return MmapProts.PROT_WRITE;
-
- case MemoryMappedFileAccess.CopyOnWrite:
- return MmapProts.PROT_WRITE | MmapProts.PROT_READ;
-
- case MemoryMappedFileAccess.ReadExecute:
- return MmapProts.PROT_EXEC;
-
- case MemoryMappedFileAccess.ReadWriteExecute:
- return MmapProts.PROT_WRITE | MmapProts.PROT_READ | MmapProts.PROT_EXEC;
-
- case MemoryMappedFileAccess.Read:
- default:
- return MmapProts.PROT_READ;
- }
- }
- internal static unsafe void MapPosix (int file_handle, long offset, ref long size, MemoryMappedFileAccess access, out IntPtr map_addr, out int offset_diff)
- {
- if (pagesize == 0)
- pagesize = Syscall.getpagesize ();
- Stat buf;
- Syscall.fstat (file_handle, out buf);
- long fsize = buf.st_size;
- if (size == 0 || size > fsize)
- size = fsize;
-
- // Align offset
- long real_offset = offset & ~(pagesize - 1);
- offset_diff = (int)(offset - real_offset);
- // FIXME: Need to determine the unix fd for the file, Handle is only
- // equal to it by accident
- //
- // The new API no longer uses FileStream everywhere, but exposes instead
- // the filename (with one exception), we could move this API to use
- // file descriptors instead of the FileStream plus its Handle.
- //
- map_addr = Syscall.mmap (IntPtr.Zero, (ulong) size,
- ToUnixProts (access),
- access == MemoryMappedFileAccess.CopyOnWrite ? MmapFlags.MAP_PRIVATE : MmapFlags.MAP_SHARED,
- file_handle, real_offset);
- if (map_addr == (IntPtr)(-1))
- throw new IOException ("mmap failed for fd#" + file_handle + "(" + offset + ", " + size + ")");
- }
- internal static bool UnmapPosix (IntPtr map_addr, ulong map_size)
- {
- return Syscall.munmap (map_addr, map_size) == 0;
- }
- }
- }
- #endif