text: // Copyright (c) 2012 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "content/browser/utility_process_host_impl.h"
  
  #include "base/bind.h"
  #include "base/bind_helpers.h"
  #include "base/command_line.h"
  #include "base/sequenced_task_runner.h"
  #include "base/utf_string_conversions.h"
  #include "content/browser/browser_child_process_host_impl.h"
  #include "content/common/child_process_host_impl.h"
  #include "content/common/utility_messages.h"
  #include "content/public/browser/browser_thread.h"
  #include "content/public/browser/content_browser_client.h"
  #include "content/public/browser/utility_process_host_client.h"
  #include "content/public/common/content_switches.h"
  #include "ipc/ipc_switches.h"
  #include "ui/base/ui_base_switches.h"
  #include "webkit/plugins/plugin_switches.h"
  
  namespace content {
  
  UtilityProcessHost* UtilityProcessHost::Create(
      UtilityProcessHostClient* client,
      base::SequencedTaskRunner* client_task_runner) {
    return new UtilityProcessHostImpl(client, client_task_runner);
  }
  
  UtilityProcessHostImpl::UtilityProcessHostImpl(
      UtilityProcessHostClient* client,
      base::SequencedTaskRunner* client_task_runner)
      : client_(client),
        client_task_runner_(client_task_runner),
        is_batch_mode_(false),
        no_sandbox_(false),
  #if defined(OS_LINUX)
        child_flags_(ChildProcessHost::CHILD_ALLOW_SELF),
  #else
        child_flags_(ChildProcessHost::CHILD_NORMAL),
  #endif
        use_linux_zygote_(false),
        started_(false) {
    process_.reset(new BrowserChildProcessHostImpl(PROCESS_TYPE_UTILITY, this));
  }
  
  UtilityProcessHostImpl::~UtilityProcessHostImpl() {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    DCHECK(!is_batch_mode_);
  }
  
  bool UtilityProcessHostImpl::Send(IPC::Message* message) {
    if (!StartProcess())
      return false;
  
    return process_->Send(message);
  }
  
  bool UtilityProcessHostImpl::StartBatchMode()  {
    CHECK(!is_batch_mode_);
    is_batch_mode_ = StartProcess();
    Send(new UtilityMsg_BatchMode_Started());
    return is_batch_mode_;
  }
  
  void UtilityProcessHostImpl::EndBatchMode()  {
    CHECK(is_batch_mode_);
    is_batch_mode_ = false;
    Send(new UtilityMsg_BatchMode_Finished());
  }
  
  void UtilityProcessHostImpl::SetExposedDir(const base::FilePath& dir) {
    exposed_dir_ = dir;
  }
  
  void UtilityProcessHostImpl::DisableSandbox() {
    no_sandbox_ = true;
  }
  
  void UtilityProcessHostImpl::EnableZygote() {
    use_linux_zygote_ = true;
  }
  
  const ChildProcessData& UtilityProcessHostImpl::GetData() {
    return process_->GetData();
  }
  
  #if defined(OS_POSIX)
  
  void UtilityProcessHostImpl::SetEnv(const base::EnvironmentVector& env) {
    env_ = env;
  }
  
  #endif  // OS_POSIX
  
  bool UtilityProcessHostImpl::StartProcess() {
    if (started_)
      return true;
    started_ = true;
  
    if (is_batch_mode_)
      return true;
    // Name must be set or metrics_service will crash in any test which
    // launches a UtilityProcessHost.
    process_->SetName(ASCIIToUTF16("utility process"));
  
    std::string channel_id = process_->GetHost()->CreateChannel();
    if (channel_id.empty())
      return false;
  
    const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
    int child_flags = child_flags_;
  
  #if defined(OS_POSIX)
    bool has_cmd_prefix = browser_command_line.HasSwitch(
        switches::kUtilityCmdPrefix);
  
    // When running under gdb, forking /proc/self/exe ends up forking the gdb
    // executable instead of Chromium. It is almost safe to assume that no
    // updates will happen while a developer is running with
    // |switches::kUtilityCmdPrefix|. See ChildProcessHost::GetChildPath() for
    // a similar case with Valgrind.
    if (has_cmd_prefix)
      child_flags = ChildProcessHost::CHILD_NORMAL;
  #endif
  
    base::FilePath exe_path = ChildProcessHost::GetChildPath(child_flags);
    if (exe_path.empty()) {
      NOTREACHED() << "Unable to get utility process binary name.";
      return false;
    }
  
    CommandLine* cmd_line = new CommandLine(exe_path);
    cmd_line->AppendSwitchASCII(switches::kProcessType,
                                switches::kUtilityProcess);
    cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id);
    std::string locale = GetContentClient()->browser()->GetApplicationLocale();
    cmd_line->AppendSwitchASCII(switches::kLang, locale);
  
    if (browser_command_line.HasSwitch(switches::kChromeFrame))
      cmd_line->AppendSwitch(switches::kChromeFrame);
    if (no_sandbox_ || browser_command_line.HasSwitch(switches::kNoSandbox))
      cmd_line->AppendSwitch(switches::kNoSandbox);
  #if defined(OS_MACOSX)
    if (browser_command_line.HasSwitch(switches::kEnableSandboxLogging))
      cmd_line->AppendSwitch(switches::kEnableSandboxLogging);
  #endif
    if (browser_command_line.HasSwitch(switches::kDebugPluginLoading))
      cmd_line->AppendSwitch(switches::kDebugPluginLoading);
  
  #if defined(OS_POSIX)
    // TODO(port): Sandbox this on Linux.  Also, zygote this to work with
    // Linux updating.
    if (has_cmd_prefix) {
      // launch the utility child process with some prefix (usually "xterm -e gdb
      // --args").
      cmd_line->PrependWrapper(browser_command_line.GetSwitchValueNative(
          switches::kUtilityCmdPrefix));
    }
  
    cmd_line->AppendSwitchPath(switches::kUtilityProcessAllowedDir, exposed_dir_);
  #endif
  
    bool use_zygote = false;
  
  #if defined(OS_LINUX)
    use_zygote = !no_sandbox_ && use_linux_zygote_;
  #endif
  
    process_->Launch(
  #if defined(OS_WIN)
        exposed_dir_,
  #elif defined(OS_POSIX)
        use_zygote,
        env_,
  #endif
        cmd_line);
  
    return true;
  }
  
  bool UtilityProcessHostImpl::OnMessageReceived(const IPC::Message& message) {
    client_task_runner_->PostTask(
        FROM_HERE,
        base::Bind(base::IgnoreResult(
            &UtilityProcessHostClient::OnMessageReceived), client_.get(),
            message));
    return true;
  }
  
  void UtilityProcessHostImpl::OnProcessCrashed(int exit_code) {
    client_task_runner_->PostTask(
        FROM_HERE,
        base::Bind(&UtilityProcessHostClient::OnProcessCrashed, client_.get(),
              exit_code));
  }
  
  }  // namespace content
  