ui: Move surface/ directory out of gfx/, up to ui/.

ui/gfx/surface/transport_dib.h

-// Copyright (c) 2011 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 UI_GFX_SURFACE_TRANSPORT_DIB_H_
-#define UI_GFX_SURFACE_TRANSPORT_DIB_H_
-#pragma once
-
-#include "base/basictypes.h"
-#include "ui/gfx/surface/surface_export.h"
-
-#if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_ANDROID)
-#include "base/shared_memory.h"
-#endif
-
-#if defined(OS_WIN)
-#include <windows.h>
-#elif defined(USE_X11)
-#include "ui/base/x/x11_util.h"
-#endif
-
-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 SURFACE_EXPORT 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; }
-
-  // Returns a value that is ONLY USEFUL FOR TESTS WHERE IT WON'T BE
-  // ACTUALLY USED AS A REAL HANDLE.
-  static Handle GetFakeHandleForTest() {
-    static int fake_handle = 10;
-    return reinterpret_cast<Handle>(fake_handle++);
-  }
-#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(); }
-
-  // Returns a value that is ONLY USEFUL FOR TESTS WHERE IT WON'T BE
-  // ACTUALLY USED AS A REAL HANDLE.
-  static Handle GetFakeHandleForTest() {
-    static int fake_handle = 10;
-    return Handle(fake_handle++, false);
-  }
-#elif defined(USE_X11)
-  typedef int Handle;  // These two ints are SysV IPC shared memory keys
-  struct Id {
-    // Ensure that default initialized Ids are invalid.
-    Id() : shmkey(-1) {
-    }
-
-    bool operator<(const Id& other) const {
-      return shmkey < other.shmkey;
-    }
-
-    int shmkey;
-  };
-
-  // Returns a default, invalid handle, that is meant to indicate a missing
-  // Transport DIB.
-  static Handle DefaultHandleValue() { return -1; }
-
-  // Returns a value that is ONLY USEFUL FOR TESTS WHERE IT WON'T BE
-  // ACTUALLY USED AS A REAL HANDLE.
-  static Handle GetFakeHandleForTest() {
-    static int fake_handle = 10;
-    return fake_handle++;
-  }
-#elif defined(OS_ANDROID)
-  typedef base::SharedMemoryHandle Handle;
-  typedef base::SharedMemoryHandle Id;
-
-  // Returns a default, invalid handle, that is meant to indicate a missing
-  // Transport DIB.
-  static Handle DefaultHandleValue() { return Handle(); }
-
-  // Returns a value that is ONLY USEFUL FOR TESTS WHERE IT WON'T BE
-  // ACTUALLY USED AS A REAL HANDLE.
-  static Handle GetFakeHandleForTest() {
-    static int fake_handle = 10;
-    return Handle(fake_handle++, false);
-  }
-#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.  The caller owns the returned object.
-  // Returns NULL on failure.
-  static TransportDIB* Map(Handle transport_dib);
-
-  // Create a new |TransportDIB| with a handle to the shared memory. This
-  // always returns a valid pointer. The DIB is not mapped.
-  static TransportDIB* CreateWithHandle(Handle handle);
-
-  // Returns true if the handle is valid.
-  static bool is_valid_handle(Handle dib);
-
-  // Returns true if the ID refers to a valid dib.
-  static bool is_valid_id(Id id);
-
-  // 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.
-  //
-  // On POSIX, this |TransportDIB| will be mapped if not already. On Windows,
-  // this |TransportDIB| will NOT be mapped and should not be mapped prior,
-  // because PlatformCanvas will map the file internally.
-  //
-  // Will return NULL on allocation failure. This could be because the image
-  // is too large to map into the current process' address space.
-  skia::PlatformCanvas* GetPlatformCanvas(int w, int h);
-
-  // Map the DIB into the current process if it is not already. This is used to
-  // map a DIB that has already been created. Returns true if the DIB is mapped.
-  bool Map();
-
-  // 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) || defined(OS_ANDROID)
-  explicit TransportDIB(base::SharedMemoryHandle dib);
-  base::SharedMemory shared_memory_;
-  uint32 sequence_num_;
-#elif defined(USE_X11)
-  Id 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);
-};
-
-#endif  // UI_GFX_SURFACE_TRANSPORT_DIB_H_