Move launchd code from chrome/browser/mac to base/mac.

This is to allow the code to be used by the Chromoting host plugin.
Also expand the interface of PIDForJob() to report if a job is loaded but not
running.

BUG=None
TEST=Compiles, unit-tests pass

Review URL: https://chromiumcodereview.appspot.com/9837098

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@129636 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 182 insertions, 0 deletions

diff --git a/base/mac/launchd.cc b/base/mac/launchd.cc
new file mode 100644
index 0000000..1d384c9
--- /dev/null
+++ b/base/mac/launchd.cc
@@ -0,0 +1,75 @@
+// 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 "base/mac/launchd.h"
+
+#include "base/logging.h"
+#include "base/mac/scoped_launch_data.h"
+
+namespace base {
+namespace mac {
+
+// 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. The caller
+// assumes ownership of the returned launch_data_t object.
+launch_data_t MessageForJob(const std::string& job_label,
+                            const char* operation) {
+  // launch_data_alloc returns something that needs to be freed.
+  ScopedLaunchData message(launch_data_alloc(LAUNCH_DATA_DICTIONARY));
+  if (!message) {
+    LOG(ERROR) << "launch_data_alloc";
+    return NULL;
+  }
+
+  // launch_data_new_string returns something that needs to be freed, but
+  // the dictionary will assume ownership when launch_data_dict_insert is
+  // called, so put it in a scoper and .release() it when given to the
+  // dictionary.
+  ScopedLaunchData job_label_launchd(launch_data_new_string(job_label.c_str()));
+  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);
+}
+
+pid_t PIDForJob(const std::string& job_label) {
+  ScopedLaunchData response(MessageForJob(job_label, LAUNCH_KEY_GETJOB));
+  if (!response) {
+    return -1;
+  }
+
+  launch_data_type_t response_type = launch_data_get_type(response);
+  if (response_type != LAUNCH_DATA_DICTIONARY) {
+    if (response_type == LAUNCH_DATA_ERRNO) {
+      LOG(ERROR) << "PIDForJob: error " << launch_data_get_errno(response);
+    } else {
+      LOG(ERROR) << "PIDForJob: expected dictionary, got " << response_type;
+    }
+    return -1;
+  }
+
+  launch_data_t pid_data = launch_data_dict_lookup(response,
+                                                   LAUNCH_JOBKEY_PID);
+  if (!pid_data)
+    return 0;
+
+  if (launch_data_get_type(pid_data) != LAUNCH_DATA_INTEGER) {
+    LOG(ERROR) << "PIDForJob: expected integer";
+    return -1;
+  }
+
+  return launch_data_get_integer(pid_data);
+}
+
+}  // namespace mac
+}  // namespace base
diff --git a/base/mac/launchd.h b/base/mac/launchd.h
new file mode 100644
index 0000000..b693687
--- /dev/null
+++ b/base/mac/launchd.h
@@ -0,0 +1,31 @@
+// 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.
+
+#ifndef BASE_MAC_LAUNCHD_H_
+#define BASE_MAC_LAUNCHD_H_
+#pragma once
+
+#include <launch.h>
+#include <sys/types.h>
+
+#include <string>
+
+namespace base {
+namespace mac {
+
+// 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. The caller
+// assumes ownership of the returned launch_data_t object.
+launch_data_t MessageForJob(const std::string& job_label,
+                            const char* operation);
+
+// Returns the process ID for |job_label| if the job is running, 0 if the job
+// is loaded but not running, or -1 on error.
+pid_t PIDForJob(const std::string& job_label);
+
+}  // namespace mac
+}  // namespace base
+
+#endif  // BASE_MAC_LAUNCHD_H_
diff --git a/base/mac/scoped_launch_data.h b/base/mac/scoped_launch_data.h
new file mode 100644
index 0000000..955c3e7
--- /dev/null
+++ b/base/mac/scoped_launch_data.h
@@ -0,0 +1,76 @@
+// 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.
+
+#ifndef BASE_MAC_SCOPED_LAUNCH_DATA_H_
+#define BASE_MAC_SCOPED_LAUNCH_DATA_H_
+#pragma once
+
+#include <launch.h>
+
+#include <algorithm>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+
+namespace base {
+namespace mac {
+
+// Just like scoped_ptr<> but for launch_data_t.
+class ScopedLaunchData {
+ public:
+  typedef launch_data_t element_type;
+
+  explicit ScopedLaunchData(launch_data_t object = NULL)
+      : object_(object) {
+  }
+
+  ~ScopedLaunchData() {
+    if (object_)
+      launch_data_free(object_);
+  }
+
+  void reset(launch_data_t object = NULL) {
+    if (object != object_) {
+      if (object_)
+        launch_data_free(object_);
+      object_ = object;
+    }
+  }
+
+  bool operator==(launch_data_t that) const {
+    return object_ == that;
+  }
+
+  bool operator!=(launch_data_t that) const {
+    return object_ != that;
+  }
+
+  operator launch_data_t() const {
+    return object_;
+  }
+
+  launch_data_t get() const {
+    return object_;
+  }
+
+  void swap(ScopedLaunchData& that) {
+    std::swap(object_, that.object_);
+  }
+
+  launch_data_t release() WARN_UNUSED_RESULT {
+    launch_data_t temp = object_;
+    object_ = NULL;
+    return temp;
+  }
+
+ private:
+  launch_data_t object_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedLaunchData);
+};
+
+}  // namespace mac
+}  // namespace base
+
+#endif  // BASE_MAC_SCOPED_LAUNCH_DATA_H_