base/mac/launchd.cc

   1 // Copyright (c) 2012 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 "base/mac/launchd.h"
   6
   7 #include "base/logging.h"
   8 #include "base/mac/scoped_launch_data.h"
   9
  10 namespace base {
  11 namespace mac {
  12
  13 // MessageForJob sends a single message to launchd with a simple dictionary
  14 // mapping |operation| to |job_label|, and returns the result of calling
  15 // launch_msg to send that message. On failure, returns NULL. The caller
  16 // assumes ownership of the returned launch_data_t object.
  17 launch_data_t MessageForJob(const std::string& job_label,
  18                             const char* operation) {
  19   // launch_data_alloc returns something that needs to be freed.
  20   ScopedLaunchData message(launch_data_alloc(LAUNCH_DATA_DICTIONARY));
  21   if (!message) {
  22     LOG(ERROR) << "launch_data_alloc";
  23     return NULL;
  24   }
  25
  26   // launch_data_new_string returns something that needs to be freed, but
  27   // the dictionary will assume ownership when launch_data_dict_insert is
  28   // called, so put it in a scoper and .release() it when given to the
  29   // dictionary.
  30   ScopedLaunchData job_label_launchd(launch_data_new_string(job_label.c_str()));
  31   if (!job_label_launchd) {
  32     LOG(ERROR) << "launch_data_new_string";
  33     return NULL;
  34   }
  35
  36   if (!launch_data_dict_insert(message,
  37                                job_label_launchd.release(),
  38                                operation)) {
  39     return NULL;
  40   }
  41
  42   return launch_msg(message);
  43 }
  44
  45 pid_t PIDForJob(const std::string& job_label) {
  46   ScopedLaunchData response(MessageForJob(job_label, LAUNCH_KEY_GETJOB));
  47   if (!response) {
  48     return -1;
  49   }
  50
  51   launch_data_type_t response_type = launch_data_get_type(response);
  52   if (response_type != LAUNCH_DATA_DICTIONARY) {
  53     if (response_type == LAUNCH_DATA_ERRNO) {
  54       LOG(ERROR) << "PIDForJob: error " << launch_data_get_errno(response);
  55     } else {
  56       LOG(ERROR) << "PIDForJob: expected dictionary, got " << response_type;
  57     }
  58     return -1;
  59   }
  60
  61   launch_data_t pid_data = launch_data_dict_lookup(response,
  62                                                    LAUNCH_JOBKEY_PID);
  63   if (!pid_data)
  64     return 0;
  65
  66   if (launch_data_get_type(pid_data) != LAUNCH_DATA_INTEGER) {
  67     LOG(ERROR) << "PIDForJob: expected integer";
  68     return -1;
  69   }
  70
  71   return launch_data_get_integer(pid_data);
  72 }
  73
  74 }  // namespace mac
  75 }  // namespace base