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