Install from disk image: Create persistent Dock icon

chrome/browser/mac/launchd.cc

+// Copyright (c) 2011 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 "chrome/browser/mac/launchd.h"
+
+#include <launch.h>
+#include <signal.h>
+
+#include "base/logging.h"
+#include "chrome/browser/mac/scoped_launch_data.h"
+
+namespace launchd {
+
+namespace {
+
+// MessageForJob sends a single message to launchd with a simple dictionary
+// mapping |operation| to |job_label|, and returns the result of calling
+// launch_msg to send that message. On failure, returns NULL.
+launch_data_t MessageForJob(const std::string& job_label,
+                            const char* operation) {
+  ScopedLaunchData message(launch_data_alloc(LAUNCH_DATA_DICTIONARY));
+  if (!message) {
+    LOG(ERROR) << "launch_data_alloc";
+    return NULL;
+  }
+
+  ScopedLaunchData job_label_launchd(launch_data_new_string(job_label.c_str()));

[Robert Sesek, 2011/06/29 18:26:42]

The memory management here warrants a comment, I think.

+  if (!job_label_launchd) {
+    LOG(ERROR) << "launch_data_new_string";
+    return NULL;
+  }
+
+  if (!launch_data_dict_insert(message,
+                               job_label_launchd.release(),
+                               operation)) {
+    return NULL;
+  }
+
+  return launch_msg(message);
+}
+
+// The internal implementation of StartJob and StopJob.
+int StartStopJob(const std::string& job_label, bool start) {
+  ScopedLaunchData response(MessageForJob(job_label,
+                                          start ? LAUNCH_KEY_STARTJOB :
+                                                  LAUNCH_KEY_STOPJOB));
+  if (!response) {
+    return -1;
+  }
+
+  if (launch_data_get_type(response) != LAUNCH_DATA_ERRNO) {
+    LOG(ERROR) << "StartStopJob: expected errno";
+    return -1;
+  }
+
+  int err = launch_data_get_errno(response);
+  if (err) {
+    LOG(ERROR) << "StartStopJob: " << err;
+  }
+
+  return err;
+}
+
+}  // namespace
+
+int StartJob(const std::string& job_label) {
+  return StartStopJob(job_label, true);
+}
+
+int StopJob(const std::string& job_label) {
+  return StartStopJob(job_label, false);
+}
+
+void RestartJob(const std::string& job_label) {
+  if (StopJob(job_label) == 0) {
+    StartJob(job_label);
+  }
+}
+
+int PIDForJob(const std::string& job_label) {
+  ScopedLaunchData response(MessageForJob(job_label, LAUNCH_KEY_GETJOB));
+  if (!response) {
+    return -1;
+  }
+
+  if (launch_data_get_type(response) != LAUNCH_DATA_DICTIONARY) {
+    LOG(ERROR) << "PIDForJob: expected dictionary";
+    return -1;
+  }
+
+  launch_data_t pid_data = launch_data_dict_lookup(response,
+                                                   LAUNCH_JOBKEY_PID);
+  if (!pid_data) {
+    LOG(ERROR) << "PIDForJob: no pid";
+    return -1;
+  }
+
+  if (launch_data_get_type(pid_data) != LAUNCH_DATA_INTEGER) {
+    LOG(ERROR) << "PIDForJob: expected integer";
+    return -1;
+  }
+
+  int pid = launch_data_get_integer(pid_data);
+  return pid;
+}
+
+void SignalJob(const std::string& job_name, int signal) {
+  int pid = PIDForJob(job_name);
+  if (pid < 0) {
+    return;
+  }
+
+  kill(pid, signal);
+}
+
+}  // namespace launchd