content/renderer/pepper/ppb_buffer_impl.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/renderer/pepper/ppb_buffer_impl.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/logging.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "content/common/pepper_file_util.h"
  12 #include "content/renderer/render_thread_impl.h"
  13 #include "ppapi/c/dev/ppb_buffer_dev.h"
  14 #include "ppapi/c/pp_bool.h"
  15 #include "ppapi/c/pp_errors.h"
  16 #include "ppapi/c/pp_instance.h"
  17 #include "ppapi/c/pp_resource.h"
  18
  19 using ppapi::thunk::PPB_Buffer_API;
  20
  21 namespace content {
  22
  23 PPB_Buffer_Impl::PPB_Buffer_Impl(PP_Instance instance)
  24     : Resource(ppapi::OBJECT_IS_IMPL, instance), size_(0), map_count_(0) {}
  25
  26 PPB_Buffer_Impl::~PPB_Buffer_Impl() {}
  27
  28 // static
  29 PP_Resource PPB_Buffer_Impl::Create(PP_Instance instance, uint32_t size) {
  30   scoped_refptr<PPB_Buffer_Impl> new_resource(CreateResource(instance, size));
  31   if (new_resource.get())
  32     return new_resource->GetReference();
  33   return 0;
  34 }
  35
  36 // static
  37 scoped_refptr<PPB_Buffer_Impl> PPB_Buffer_Impl::CreateResource(
  38     PP_Instance instance,
  39     uint32_t size) {
  40   scoped_refptr<PPB_Buffer_Impl> buffer(new PPB_Buffer_Impl(instance));
  41   if (!buffer->Init(size))
  42     return scoped_refptr<PPB_Buffer_Impl>();
  43   return buffer;
  44 }
  45
  46 PPB_Buffer_Impl* PPB_Buffer_Impl::AsPPB_Buffer_Impl() { return this; }
  47
  48 PPB_Buffer_API* PPB_Buffer_Impl::AsPPB_Buffer_API() { return this; }
  49
  50 bool PPB_Buffer_Impl::Init(uint32_t size) {
  51   if (size == 0)
  52     return false;
  53   size_ = size;
  54   shared_memory_.reset(
  55       RenderThread::Get()->HostAllocateSharedMemoryBuffer(size).release());
  56   return shared_memory_.get() != NULL;
  57 }
  58
  59 PP_Bool PPB_Buffer_Impl::Describe(uint32_t* size_in_bytes) {
  60   *size_in_bytes = size_;
  61   return PP_TRUE;
  62 }
  63
  64 PP_Bool PPB_Buffer_Impl::IsMapped() {
  65   return PP_FromBool(!!shared_memory_->memory());
  66 }
  67
  68 void* PPB_Buffer_Impl::Map() {
  69   DCHECK(size_);
  70   DCHECK(shared_memory_.get());
  71   if (map_count_++ == 0)
  72     shared_memory_->Map(size_);
  73   return shared_memory_->memory();
  74 }
  75
  76 void PPB_Buffer_Impl::Unmap() {
  77   if (--map_count_ == 0)
  78     shared_memory_->Unmap();
  79 }
  80
  81 int32_t PPB_Buffer_Impl::GetSharedMemory(base::SharedMemory** shm) {
  82   *shm = shared_memory_.get();
  83   return PP_OK;
  84 }
  85
  86 BufferAutoMapper::BufferAutoMapper(PPB_Buffer_API* api) : api_(api) {
  87   needs_unmap_ = !PP_ToBool(api->IsMapped());
  88   data_ = api->Map();
  89   api->Describe(&size_);
  90 }
  91
  92 BufferAutoMapper::~BufferAutoMapper() {
  93   if (needs_unmap_)
  94     api_->Unmap();
  95 }
  96
  97 }  // namespace content