extensions/browser/api/system_info/system_info_provider.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 "extensions/browser/api/system_info/system_info_provider.h"
   6
   7 #include "base/bind.h"
   8 #include "content/public/browser/browser_thread.h"
   9
  10 namespace extensions {
  11
  12 SystemInfoProvider::SystemInfoProvider() : is_waiting_for_completion_(false) {
  13   base::SequencedWorkerPool* pool = content::BrowserThread::GetBlockingPool();
  14   worker_pool_ = pool->GetSequencedTaskRunnerWithShutdownBehavior(
  15       pool->GetSequenceToken(),
  16       base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN);
  17 }
  18
  19 SystemInfoProvider::~SystemInfoProvider() {
  20 }
  21
  22 void SystemInfoProvider::PrepareQueryOnUIThread() {
  23 }
  24
  25 void SystemInfoProvider::InitializeProvider(
  26     const base::Closure& do_query_info_callback) {
  27   do_query_info_callback.Run();
  28 }
  29
  30 void SystemInfoProvider::StartQueryInfo(
  31     const QueryInfoCompletionCallback& callback) {
  32   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  33   DCHECK(!callback.is_null());
  34
  35   callbacks_.push(callback);
  36
  37   if (is_waiting_for_completion_)
  38     return;
  39
  40   is_waiting_for_completion_ = true;
  41
  42   InitializeProvider(
  43       base::Bind(&SystemInfoProvider::StartQueryInfoPostInitialization, this));
  44 }
  45
  46 void SystemInfoProvider::OnQueryCompleted(bool success) {
  47   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  48
  49   while (!callbacks_.empty()) {
  50     QueryInfoCompletionCallback callback = callbacks_.front();
  51     callback.Run(success);
  52     callbacks_.pop();
  53   }
  54
  55   is_waiting_for_completion_ = false;
  56 }
  57
  58 void SystemInfoProvider::StartQueryInfoPostInitialization() {
  59   PrepareQueryOnUIThread();
  60   // Post the custom query info task to blocking pool for information querying
  61   // and reply with OnQueryCompleted.
  62   base::PostTaskAndReplyWithResult(
  63       worker_pool_.get(),
  64       FROM_HERE,
  65       base::Bind(&SystemInfoProvider::QueryInfo, this),
  66       base::Bind(&SystemInfoProvider::OnQueryCompleted, this));
  67 }
  68
  69 }  // namespace extensions