src/chrome/browser/media_galleries/fileapi/safe_media_metadata_parser.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/browser/media_galleries/fileapi/safe_media_metadata_parser.h"
   6
   7 #include "chrome/browser/extensions/blob_reader.h"
   8 #include "chrome/common/chrome_utility_messages.h"
   9 #include "content/public/browser/browser_thread.h"
  10 #include "content/public/browser/child_process_data.h"
  11 #include "content/public/browser/utility_process_host.h"
  12
  13 using content::BrowserThread;
  14
  15 namespace metadata {
  16
  17 namespace {
  18
  19 // Completes the Blob byte request by forwarding it to the utility process.
  20 void OnBlobReaderDone(
  21     const base::WeakPtr<content::UtilityProcessHost>& utility_process_host,
  22     int64 request_id,
  23     scoped_ptr<std::string> data,
  24     int64 /* blob_total_size */) {
  25   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  26
  27   if (!utility_process_host.get())
  28     return;
  29   utility_process_host->Send(new ChromeUtilityMsg_RequestBlobBytes_Finished(
  30       request_id, *data));
  31 }
  32
  33 }  // namespace
  34
  35 SafeMediaMetadataParser::SafeMediaMetadataParser(Profile* profile,
  36                                                  const std::string& blob_uuid,
  37                                                  int64 blob_size,
  38                                                  const std::string& mime_type)
  39     : profile_(profile),
  40       blob_uuid_(blob_uuid),
  41       blob_size_(blob_size),
  42       mime_type_(mime_type),
  43       parser_state_(INITIAL_STATE) {
  44   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  45 }
  46
  47 void SafeMediaMetadataParser::Start(const DoneCallback& callback) {
  48   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  49
  50   BrowserThread::PostTask(
  51       BrowserThread::IO,
  52       FROM_HERE,
  53       base::Bind(&SafeMediaMetadataParser::StartWorkOnIOThread, this,
  54                  callback));
  55 }
  56
  57 SafeMediaMetadataParser::~SafeMediaMetadataParser() {
  58 }
  59
  60 void SafeMediaMetadataParser::StartWorkOnIOThread(
  61     const DoneCallback& callback) {
  62   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  63   DCHECK_EQ(INITIAL_STATE, parser_state_);
  64   DCHECK(!callback.is_null());
  65
  66   callback_ = callback;
  67
  68   utility_process_host_ = content::UtilityProcessHost::Create(
  69       this, base::MessageLoopProxy::current())->AsWeakPtr();
  70
  71   utility_process_host_->Send(
  72       new ChromeUtilityMsg_ParseMediaMetadata(mime_type_, blob_size_));
  73
  74   parser_state_ = STARTED_PARSING_STATE;
  75 }
  76
  77 void SafeMediaMetadataParser::OnParseMediaMetadataFinished(
  78     bool parse_success, const base::DictionaryValue& metadata_dictionary) {
  79   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  80   DCHECK(!callback_.is_null());
  81
  82   if (parser_state_ != STARTED_PARSING_STATE)
  83     return;
  84
  85   BrowserThread::PostTask(
  86       BrowserThread::UI,
  87       FROM_HERE,
  88       base::Bind(callback_, parse_success,
  89                  base::Owned(metadata_dictionary.DeepCopy())));
  90   parser_state_ = FINISHED_PARSING_STATE;
  91 }
  92
  93 void SafeMediaMetadataParser::OnUtilityProcessRequestBlobBytes(
  94     int64 request_id, int64 byte_start, int64 length) {
  95   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  96
  97   // BlobReader is self-deleting.
  98   BlobReader* reader = new BlobReader(
  99       profile_,
 100       blob_uuid_,
 101       base::Bind(&OnBlobReaderDone, utility_process_host_, request_id));
 102   reader->SetByteRange(byte_start, length);
 103   reader->Start();
 104 }
 105
 106 void SafeMediaMetadataParser::OnProcessCrashed(int exit_code) {
 107   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 108   DCHECK(!callback_.is_null());
 109
 110   BrowserThread::PostTask(
 111       BrowserThread::UI,
 112       FROM_HERE,
 113       base::Bind(callback_, false, base::Owned(new base::DictionaryValue)));
 114   parser_state_ = FINISHED_PARSING_STATE;
 115 }
 116
 117 bool SafeMediaMetadataParser::OnMessageReceived(const IPC::Message& message) {
 118   bool handled = true;
 119   IPC_BEGIN_MESSAGE_MAP(SafeMediaMetadataParser, message)
 120     IPC_MESSAGE_HANDLER(
 121         ChromeUtilityHostMsg_ParseMediaMetadata_Finished,
 122         OnParseMediaMetadataFinished)
 123     IPC_MESSAGE_HANDLER(
 124         ChromeUtilityHostMsg_RequestBlobBytes,
 125         OnUtilityProcessRequestBlobBytes)
 126     IPC_MESSAGE_UNHANDLED(handled = false)
 127   IPC_END_MESSAGE_MAP()
 128   return handled;
 129 }
 130
 131 }  // namespace metadata