src/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/strings/string_number_conversions.h"
  16 #include "base/task_runner.h"
  17 #include "base/task_runner_util.h"
  18 #include "mojo/shell/context.h"
  19 #include "mojo/shell/switches.h"
  20
  21 namespace mojo {
  22 namespace shell {
  23
  24 ChildProcessHost::ChildProcessHost(Context* context,
  25                                    Delegate* delegate,
  26                                    ChildProcess::Type type)
  27     : context_(context),
  28       delegate_(delegate),
  29       type_(type),
  30       child_process_handle_(base::kNullProcessHandle) {
  31   DCHECK(delegate);
  32   platform_channel_ = platform_channel_pair_.PassServerHandle();
  33   CHECK(platform_channel_.is_valid());
  34 }
  35
  36 ChildProcessHost::~ChildProcessHost() {
  37   if (child_process_handle_ != base::kNullProcessHandle) {
  38     LOG(WARNING) << "Destroying ChildProcessHost with unjoined child";
  39     base::CloseProcessHandle(child_process_handle_);
  40     child_process_handle_ = base::kNullProcessHandle;
  41   }
  42 }
  43
  44 void ChildProcessHost::Start() {
  45   DCHECK_EQ(child_process_handle_, base::kNullProcessHandle);
  46
  47   delegate_->WillStart();
  48
  49   CHECK(base::PostTaskAndReplyWithResult(
  50       context_->task_runners()->blocking_pool(),
  51       FROM_HERE,
  52       base::Bind(&ChildProcessHost::DoLaunch, base::Unretained(this)),
  53       base::Bind(&ChildProcessHost::DidLaunch, base::Unretained(this))));
  54 }
  55
  56 int ChildProcessHost::Join() {
  57   DCHECK_NE(child_process_handle_, base::kNullProcessHandle);
  58   int rv = -1;
  59   // Note: |WaitForExitCode()| closes the process handle.
  60   LOG_IF(ERROR, !base::WaitForExitCode(child_process_handle_, &rv))
  61       << "Failed to wait for child process";
  62   child_process_handle_ = base::kNullProcessHandle;
  63   return rv;
  64 }
  65
  66 bool ChildProcessHost::DoLaunch() {
  67   static const char* kForwardSwitches[] = {
  68     switches::kTraceToConsole,
  69     switches::kV,
  70     switches::kVModule,
  71   };
  72
  73   const base::CommandLine* parent_command_line =
  74       base::CommandLine::ForCurrentProcess();
  75   base::CommandLine child_command_line(parent_command_line->GetProgram());
  76   child_command_line.CopySwitchesFrom(*parent_command_line, kForwardSwitches,
  77                                       arraysize(kForwardSwitches));
  78   child_command_line.AppendSwitchASCII(
  79       switches::kChildProcessType, base::IntToString(static_cast<int>(type_)));
  80
  81   embedder::HandlePassingInformation handle_passing_info;
  82   platform_channel_pair_.PrepareToPassClientHandleToChildProcess(
  83       &child_command_line, &handle_passing_info);
  84
  85   base::LaunchOptions options;
  86 #if defined(OS_WIN)
  87   options.start_hidden = true;
  88   options.handles_to_inherit = &handle_passing_info;
  89 #elif defined(OS_POSIX)
  90   options.fds_to_remap = &handle_passing_info;
  91 #endif
  92
  93   if (!base::LaunchProcess(child_command_line, options, &child_process_handle_))
  94     return false;
  95
  96   platform_channel_pair_.ChildProcessLaunched();
  97   return true;
  98 }
  99
 100 void ChildProcessHost::DidLaunch(bool success) {
 101   delegate_->DidStart(success);
 102 }
 103
 104 }  // namespace shell
 105 }  // namespace mojo