mojo/shell/child_process_host.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 "mojo/shell/child_process_host.h"
   6
   7 #include "base/base_switches.h"
   8 #include "base/bind.h"
   9 #include "base/command_line.h"
  10 #include "base/location.h"
  11 #include "base/logging.h"
  12 #include "base/macros.h"
  13 #include "base/process/kill.h"
  14 #include "base/process/launch.h"
  15 #include "base/task_runner.h"
  16 #include "base/task_runner_util.h"
  17 #include "mojo/shell/context.h"
  18 #include "mojo/shell/switches.h"
  19
  20 namespace mojo {
  21 namespace shell {
  22
  23 ChildProcessHost::ChildProcessHost(Context* context) : context_(context) {
  24   platform_channel_ = platform_channel_pair_.PassServerHandle();
  25   CHECK(platform_channel_.is_valid());
  26 }
  27
  28 ChildProcessHost::~ChildProcessHost() {
  29   if (child_process_.IsValid()) {
  30     LOG(WARNING) << "Destroying ChildProcessHost with unjoined child";
  31     child_process_.Close();
  32   }
  33 }
  34
  35 void ChildProcessHost::Start() {
  36   DCHECK(!child_process_.IsValid());
  37
  38   WillStart();
  39
  40   CHECK(base::PostTaskAndReplyWithResult(
  41       context_->task_runners()->blocking_pool(), FROM_HERE,
  42       base::Bind(&ChildProcessHost::DoLaunch, base::Unretained(this)),
  43       base::Bind(&ChildProcessHost::DidStart, base::Unretained(this))));
  44 }
  45
  46 int ChildProcessHost::Join() {
  47   DCHECK(child_process_.IsValid());
  48   int rv = -1;
  49   LOG_IF(ERROR, !child_process_.WaitForExit(&rv))
  50       << "Failed to wait for child process";
  51   child_process_.Close();
  52   return rv;
  53 }
  54
  55 bool ChildProcessHost::DoLaunch() {
  56   static const char* kForwardSwitches[] = {
  57       switches::kTraceToConsole, switches::kV, switches::kVModule,
  58   };
  59
  60   const base::CommandLine* parent_command_line =
  61       base::CommandLine::ForCurrentProcess();
  62   base::CommandLine child_command_line(parent_command_line->GetProgram());
  63   child_command_line.CopySwitchesFrom(*parent_command_line, kForwardSwitches,
  64                                       arraysize(kForwardSwitches));
  65   child_command_line.AppendSwitch(switches::kChildProcess);
  66
  67   embedder::HandlePassingInformation handle_passing_info;
  68   platform_channel_pair_.PrepareToPassClientHandleToChildProcess(
  69       &child_command_line, &handle_passing_info);
  70
  71   base::LaunchOptions options;
  72 #if defined(OS_WIN)
  73   options.start_hidden = true;
  74   options.handles_to_inherit = &handle_passing_info;
  75 #elif defined(OS_POSIX)
  76   options.fds_to_remap = &handle_passing_info;
  77 #endif
  78   DVLOG(2) << "Launching child with command line: "
  79            << child_command_line.GetCommandLineString();
  80   child_process_ = base::LaunchProcess(child_command_line, options);
  81   if (!child_process_.IsValid())
  82     return false;
  83
  84   platform_channel_pair_.ChildProcessLaunched();
  85   return true;
  86 }
  87
  88 }  // namespace shell
  89 }  // namespace mojo