chrome/utility/media_galleries/ipc_data_source.cc

   1 // Copyright 2014 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 "chrome/utility/media_galleries/ipc_data_source.h"
   6
   7 #include "chrome/common/chrome_utility_messages.h"
   8 #include "content/public/utility/utility_thread.h"
   9
  10 namespace metadata {
  11
  12 IPCDataSource::IPCDataSource(int64 total_size)
  13     : total_size_(total_size),
  14       next_request_id_(0) {
  15 }
  16
  17 IPCDataSource::~IPCDataSource() {}
  18
  19 void IPCDataSource::set_host(media::DataSourceHost* host) {
  20   DataSource::set_host(host);
  21   if (media::DataSource::host()) {
  22     media::DataSource::host()->SetTotalBytes(total_size_);
  23   }
  24 }
  25
  26 void IPCDataSource::Stop(const base::Closure& callback) {
  27   callback.Run();
  28 }
  29
  30 void IPCDataSource::Read(int64 position, int size, uint8* data,
  31                          const DataSource::ReadCB& read_cb) {
  32   CHECK_GE(total_size_, 0);
  33   CHECK_GE(position, 0);
  34   CHECK_GE(size, 0);
  35
  36   // Cap position and size within bounds.
  37   position = std::min(position, total_size_);
  38   int64 clamped_size =
  39       std::min(static_cast<int64>(size), total_size_ - position);
  40
  41   int64 request_id = ++next_request_id_;
  42
  43   Request request;
  44   request.destination = data;
  45   request.callback = read_cb;
  46
  47   pending_requests_[request_id] = request;
  48   content::UtilityThread::Get()->Send(new ChromeUtilityHostMsg_RequestBlobBytes(
  49       request_id, position, clamped_size));
  50 }
  51
  52 bool IPCDataSource::GetSize(int64* size_out) {
  53   *size_out = total_size_;
  54   return true;
  55 }
  56
  57 bool IPCDataSource::IsStreaming() {
  58   return false;
  59 }
  60
  61 void IPCDataSource::SetBitrate(int bitrate) {
  62 }
  63
  64 bool IPCDataSource::OnMessageReceived(const IPC::Message& message) {
  65   bool handled = true;
  66   IPC_BEGIN_MESSAGE_MAP(IPCDataSource, message)
  67     IPC_MESSAGE_HANDLER(ChromeUtilityMsg_RequestBlobBytes_Finished,
  68                         OnRequestBlobBytesFinished)
  69     IPC_MESSAGE_UNHANDLED(handled = false)
  70   IPC_END_MESSAGE_MAP()
  71   return handled;
  72 }
  73
  74 IPCDataSource::Request::Request()
  75     : destination(NULL) {
  76 }
  77
  78 IPCDataSource::Request::~Request() {
  79 }
  80
  81 void IPCDataSource::OnRequestBlobBytesFinished(int64 request_id,
  82                                                const std::string& bytes) {
  83   std::map<int64, Request>::iterator it = pending_requests_.find(request_id);
  84
  85   if (it == pending_requests_.end())
  86     return;
  87
  88   std::copy(bytes.begin(), bytes.end(), it->second.destination);
  89   it->second.callback.Run(bytes.size());
  90
  91   pending_requests_.erase(it);
  92 }
  93
  94 }  // namespace metadata