diff options
Diffstat (limited to 'chrome/common/transport_dib.h')
| -rw-r--r-- | chrome/common/transport_dib.h | 156 |
1 files changed, 0 insertions, 156 deletions
diff --git a/chrome/common/transport_dib.h b/chrome/common/transport_dib.h deleted file mode 100644 index 4f8051e..0000000 --- a/chrome/common/transport_dib.h +++ /dev/null @@ -1,156 +0,0 @@ -// Copyright (c) 2010 The Chromium Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#ifndef CHROME_COMMON_TRANSPORT_DIB_H_ -#define CHROME_COMMON_TRANSPORT_DIB_H_ - -#include "base/basictypes.h" - -#if defined(OS_WIN) || defined(OS_MACOSX) -#include "base/shared_memory.h" -#endif - -#if defined(OS_WIN) -#include <windows.h> -#elif defined(USE_X11) -#include "chrome/common/x11_util.h" -#endif - -namespace gfx { -class Size; -} -namespace skia { -class PlatformCanvas; -} - -// ----------------------------------------------------------------------------- -// A TransportDIB is a block of memory that is used to transport pixels -// between processes: from the renderer process to the browser, and -// between renderer and plugin processes. -// ----------------------------------------------------------------------------- -class TransportDIB { - public: - ~TransportDIB(); - - // Two typedefs are defined. A Handle is the type which can be sent over - // the wire so that the remote side can map the transport DIB. The Id typedef - // is sufficient to identify the transport DIB when you know that the remote - // side already may have it mapped. -#if defined(OS_WIN) - typedef HANDLE Handle; - // On Windows, the Id type includes a sequence number (epoch) to solve an ABA - // issue: - // 1) Process A creates a transport DIB with HANDLE=1 and sends to B. - // 2) Process B maps the transport DIB and caches 1 -> DIB. - // 3) Process A closes the transport DIB and creates a new one. The new DIB - // is also assigned HANDLE=1. - // 4) Process A sends the Handle to B, but B incorrectly believes that it - // already has it cached. - struct HandleAndSequenceNum { - HandleAndSequenceNum() - : handle(NULL), - sequence_num(0) { - } - - HandleAndSequenceNum(HANDLE h, uint32 seq_num) - : handle(h), - sequence_num(seq_num) { - } - - bool operator< (const HandleAndSequenceNum& other) const { - // Use the lexicographic order on the tuple <handle, sequence_num>. - if (other.handle != handle) - return other.handle < handle; - return other.sequence_num < sequence_num; - } - - HANDLE handle; - uint32 sequence_num; - }; - typedef HandleAndSequenceNum Id; - - // Returns a default, invalid handle, that is meant to indicate a missing - // Transport DIB. - static Handle DefaultHandleValue() { return NULL; } -#elif defined(OS_MACOSX) - typedef base::SharedMemoryHandle Handle; - // On Mac, the inode number of the backing file is used as an id. - typedef base::SharedMemoryId Id; - - // Returns a default, invalid handle, that is meant to indicate a missing - // Transport DIB. - static Handle DefaultHandleValue() { return Handle(); } -#elif defined(USE_X11) - typedef int Handle; // These two ints are SysV IPC shared memory keys - typedef int Id; - - // Returns a default, invalid handle, that is meant to indicate a missing - // Transport DIB. - static Handle DefaultHandleValue() { return -1; } -#endif - - // Create a new TransportDIB, returning NULL on failure. - // - // The size is the minimum size in bytes of the memory backing the transport - // DIB (we may actually allocate more than that to give us better reuse when - // cached). - // - // The sequence number is used to uniquely identify the transport DIB. It - // should be unique for all transport DIBs ever created in the same - // renderer. - static TransportDIB* Create(size_t size, uint32 sequence_num); - - // Map the referenced transport DIB. Returns NULL on failure. - static TransportDIB* Map(Handle transport_dib); - - // Returns true if the handle is valid. - static bool is_valid(Handle dib); - - // Returns a canvas using the memory of this TransportDIB. The returned - // pointer will be owned by the caller. The bitmap will be of the given size, - // which should fit inside this memory. - skia::PlatformCanvas* GetPlatformCanvas(int w, int h); - - // Return a pointer to the shared memory - void* memory() const; - - // Return the maximum size of the shared memory. This is not the amount of - // data which is valid, you have to know that via other means, this is simply - // the maximum amount that /could/ be valid. - size_t size() const { return size_; } - - // Return the identifier which can be used to refer to this shared memory - // on the wire. - Id id() const; - - // Return a handle to the underlying shared memory. This can be sent over the - // wire to give this transport DIB to another process. - Handle handle() const; - -#if defined(USE_X11) - // Map the shared memory into the X server and return an id for the shared - // segment. - XID MapToX(Display* connection); -#endif - - private: - TransportDIB(); -#if defined(OS_WIN) || defined(OS_MACOSX) - explicit TransportDIB(base::SharedMemoryHandle dib); - base::SharedMemory shared_memory_; - uint32 sequence_num_; -#elif defined(USE_X11) - int key_; // SysV shared memory id - void* address_; // mapped address - XSharedMemoryId x_shm_; // X id for the shared segment - Display* display_; // connection to the X server -#endif - size_t size_; // length, in bytes - - DISALLOW_COPY_AND_ASSIGN(TransportDIB); -}; - -class MessageLoop; - -#endif // CHROME_COMMON_TRANSPORT_DIB_H_ |
