Update linux chromoting host to run separate instance of Pulseaudio.

Now the host sets environment for pulseaudio so that we use separate instance
of pulseaudio server and the audio is rederected to the pipe that the host
reads from.

BUG=145891

Review URL: https://chromiumcodereview.appspot.com/10916108

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@155559 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 79 insertions, 23 deletions

diff --git a/remoting/tools/me2me_virtual_host.py b/remoting/tools/me2me_virtual_host.py
index 9d23268..1438bf4 100755
--- a/remoting/tools/me2me_virtual_host.py
+++ b/remoting/tools/me2me_virtual_host.py
@@ -58,6 +58,7 @@ os.environ["XAUTHORITY"] = X_AUTH_FILE
 # Globals needed by the atexit cleanup() handler.
 g_desktops = []
 g_pidfile = None
+g_host_hash = hashlib.md5(socket.gethostname()).hexdigest()
 
 class Config:
   def __init__(self, path):
@@ -166,6 +167,7 @@ class Desktop:
     self.host_proc = None
     self.child_env = None
     self.sizes = sizes
+    self.pulseaudio_pipe = None
     g_desktops.append(self)
 
   @staticmethod
@@ -177,7 +179,69 @@ class Desktop:
       display += 1
     return display
 
-  def launch_x_server(self, extra_x_args):
+  def _init_child_env(self):
+    # Create clean environment for new session, so it is cleanly separated from
+    # the user's console X session.
+    self.child_env = {}
+    for key in [
+        "HOME",
+        "LANG",
+        "LOGNAME",
+        "PATH",
+        "SHELL",
+        "USER",
+        "USERNAME",
+        LOG_FILE_ENV_VAR]:
+      if os.environ.has_key(key):
+        self.child_env[key] = os.environ[key]
+
+  def _setup_pulseaudio(self):
+    self.pulseaudio_pipe = None
+
+    # pulseaudio uses UNIX sockets for communication. Length of UNIX socket
+    # name is limited to 108 characters, so audio will not work properly if
+    # the path is too long. To workaround this problem we use only first 10
+    # symbols of the host hash.
+    pulse_path = os.path.join(CONFIG_DIR,
+                              "pulseaudio#%s" % g_host_hash[0:10])
+    if len(pulse_path) + len("/native") >= 108:
+      logging.error("Audio will not be enabled because pulseaudio UNIX " +
+                    "socket path is too long.")
+      return False
+
+    sink_name = "chrome_remote_desktop_session"
+    pipe_name = os.path.join(pulse_path, "fifo_output")
+
+    try:
+      if not os.path.exists(pulse_path):
+        os.mkdir(pulse_path)
+      if not os.path.exists(pipe_name):
+        os.mkfifo(pipe_name)
+    except IOError, e:
+      logging.error("Failed to create pulseaudio pipe: " + str(e))
+      return False
+
+    try:
+      pulse_config = open(os.path.join(pulse_path, "default.pa"), "w")
+      pulse_config.write("load-module module-native-protocol-unix\n")
+      pulse_config.write(
+          ("load-module module-pipe-sink sink_name=%s file=\"%s\" " +
+           "rate=44100 channels=2 format=s16le\n") %
+          (sink_name, pipe_name))
+      pulse_config.close()
+    except IOError, e:
+      logging.error("Failed to write pulseaudio config: " + str(e))
+      return False
+
+    self.child_env["PULSE_CONFIG_PATH"] = pulse_path
+    self.child_env["PULSE_RUNTIME_PATH"] = pulse_path
+    self.child_env["PULSE_STATE_PATH"] = pulse_path
+    self.child_env["PULSE_SINK"] = sink_name
+    self.pulseaudio_pipe = pipe_name
+
+    return True
+
+  def _launch_x_server(self, extra_x_args):
     devnull = open(os.devnull, "rw")
     display = self.get_unused_display_number()
     ret_code = subprocess.call("xauth add :%d . `mcookie`" % display,
@@ -204,22 +268,8 @@ class Desktop:
     if not self.x_proc.pid:
       raise Exception("Could not start Xvfb.")
 
-    # Create clean environment for new session, so it is cleanly separated from
-    # the user's console X session.
-    self.child_env = {
-        "DISPLAY": ":%d" % display,
-        "CHROME_REMOTE_DESKTOP_SESSION": "1" }
-    for key in [
-        "HOME",
-        "LANG",
-        "LOGNAME",
-        "PATH",
-        "SHELL",
-        "USER",
-        "USERNAME",
-        LOG_FILE_ENV_VAR]:
-      if os.environ.has_key(key):
-        self.child_env[key] = os.environ[key]
+    self.child_env["DISPLAY"] = ":%d" % display
+    self.child_env["CHROME_REMOTE_DESKTOP_SESSION"] = "1"
 
     # Wait for X to be active.
     for _test in range(5):
@@ -271,7 +321,7 @@ class Desktop:
 
     devnull.close()
 
-  def launch_x_session(self):
+  def _launch_x_session(self):
     # Start desktop session
     # The /dev/null input redirection is necessary to prevent the X session
     # reading from stdin.  If this code runs as a shell background job in a
@@ -286,9 +336,17 @@ class Desktop:
     if not self.session_proc.pid:
       raise Exception("Could not start X session")
 
+  def launch_session(self, x_args):
+    self._init_child_env()
+    self._setup_pulseaudio()
+    self._launch_x_server(x_args)
+    self._launch_x_session()
+
   def launch_host(self, host_config):
     # Start remoting host
     args = [locate_executable(HOST_BINARY_NAME), "--host-config=/dev/stdin"]
+    if self.pulseaudio_pipe:
+      args.append("--audio-pipe-name=%s" % self.pulseaudio_pipe)
     self.host_proc = subprocess.Popen(args, env=self.child_env,
                                       stdin=subprocess.PIPE)
     logging.info(args)
@@ -578,8 +636,7 @@ Web Store: https://chrome.google.com/remotedesktop"""
                     help="Prints version of the host.")
   (options, args) = parser.parse_args()
 
-  host_hash = hashlib.md5(socket.gethostname()).hexdigest()
-  pid_filename = os.path.join(CONFIG_DIR, "host#%s.pid" % host_hash)
+  pid_filename = os.path.join(CONFIG_DIR, "host#%s.pid" % g_host_hash)
 
   # Check for a modal command-line option (start, stop, etc.)
   if options.check_running:
@@ -656,7 +713,7 @@ Web Store: https://chrome.google.com/remotedesktop"""
 
   atexit.register(cleanup)
 
-  config_filename = os.path.join(CONFIG_DIR, "host#%s.json" % host_hash)
+  config_filename = os.path.join(CONFIG_DIR, "host#%s.json" % g_host_hash)
   host_config = Config(config_filename)
 
   for s in [signal.SIGHUP, signal.SIGINT, signal.SIGTERM, signal.SIGUSR1]:
@@ -727,8 +784,7 @@ Web Store: https://chrome.google.com/remotedesktop"""
         # Neither process has been started yet. Do so now.
         logging.info("Launching X server and X session.")
         last_launch_time = time.time()
-        desktop.launch_x_server(args)
-        desktop.launch_x_session()
+        desktop.launch_session(args)
       else:
         # Both processes have terminated. Since the user's desktop is already
         # gone at this point, there's no state to lose and now is a good time