components/safe_json/safe_json_parser_impl.cc

   1 // Copyright 2013 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 "components/safe_json/safe_json_parser_impl.h"
   6
   7 #include "base/sequenced_task_runner.h"
   8 #include "base/strings/utf_string_conversions.h"
   9 #include "base/thread_task_runner_handle.h"
  10 #include "base/tuple.h"
  11 #include "base/values.h"
  12 #include "components/safe_json/safe_json_parser_messages.h"
  13 #include "content/public/browser/browser_thread.h"
  14 #include "content/public/browser/utility_process_host.h"
  15 #include "grit/components_strings.h"
  16 #include "ipc/ipc_message_macros.h"
  17 #include "ui/base/l10n/l10n_util.h"
  18
  19 using content::BrowserThread;
  20 using content::UtilityProcessHost;
  21
  22 namespace safe_json {
  23
  24 SafeJsonParserImpl::SafeJsonParserImpl(const std::string& unsafe_json,
  25                                        const SuccessCallback& success_callback,
  26                                        const ErrorCallback& error_callback)
  27     : unsafe_json_(unsafe_json),
  28       success_callback_(success_callback),
  29       error_callback_(error_callback) {}
  30
  31 SafeJsonParserImpl::~SafeJsonParserImpl() {
  32 }
  33
  34 void SafeJsonParserImpl::StartWorkOnIOThread() {
  35   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  36   UtilityProcessHost* host = UtilityProcessHost::Create(
  37       this, base::ThreadTaskRunnerHandle::Get().get());
  38   host->SetName(
  39       l10n_util::GetStringUTF16(IDS_UTILITY_PROCESS_JSON_PARSER_NAME));
  40   host->Send(new SafeJsonParserMsg_ParseJSON(unsafe_json_));
  41 }
  42
  43 void SafeJsonParserImpl::OnJSONParseSucceeded(const base::ListValue& wrapper) {
  44   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  45   const base::Value* value = NULL;
  46   CHECK(wrapper.Get(0, &value));
  47
  48   parsed_json_.reset(value->DeepCopy());
  49   ReportResults();
  50 }
  51
  52 void SafeJsonParserImpl::OnJSONParseFailed(const std::string& error_message) {
  53   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  54   error_ = error_message;
  55   ReportResults();
  56 }
  57
  58 void SafeJsonParserImpl::ReportResults() {
  59   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  60
  61   caller_task_runner_->PostTask(
  62       FROM_HERE,
  63       base::Bind(&SafeJsonParserImpl::ReportResultsOnOriginThread, this));
  64 }
  65
  66 void SafeJsonParserImpl::ReportResultsOnOriginThread() {
  67   DCHECK(caller_task_runner_->RunsTasksOnCurrentThread());
  68   if (error_.empty() && parsed_json_) {
  69     if (!success_callback_.is_null())
  70       success_callback_.Run(parsed_json_.Pass());
  71   } else {
  72     if (!error_callback_.is_null())
  73       error_callback_.Run(error_);
  74   }
  75 }
  76
  77 bool SafeJsonParserImpl::OnMessageReceived(const IPC::Message& message) {
  78   bool handled = true;
  79   IPC_BEGIN_MESSAGE_MAP(SafeJsonParserImpl, message)
  80     IPC_MESSAGE_HANDLER(SafeJsonParserHostMsg_ParseJSON_Succeeded,
  81                         OnJSONParseSucceeded)
  82     IPC_MESSAGE_HANDLER(SafeJsonParserHostMsg_ParseJSON_Failed,
  83                         OnJSONParseFailed)
  84     IPC_MESSAGE_UNHANDLED(handled = false)
  85   IPC_END_MESSAGE_MAP()
  86   return handled;
  87 }
  88
  89 void SafeJsonParserImpl::Start() {
  90   caller_task_runner_ = base::ThreadTaskRunnerHandle::Get();
  91
  92   BrowserThread::PostTask(
  93       BrowserThread::IO, FROM_HERE,
  94       base::Bind(&SafeJsonParserImpl::StartWorkOnIOThread, this));
  95 }
  96
  97 }  // namespace safe_json