ALSA Backend: Separate Device Reservation into its own class

diff --git a/libs/backends/alsa/alsa_audiobackend.cc b/libs/backends/alsa/alsa_audiobackend.cc
index 525ff2e75733db04b4a03e0a46a11aeb909f4568..93ec8dead84d8e36b2dc6fb1c108cb1abaaf23d0 100644 (file)
--- a/libs/backends/alsa/alsa_audiobackend.cc
+++ b/libs/backends/alsa/alsa_audiobackend.cc
@@ -59,7 +59,6 @@ AlsaAudioBackend::AlsaAudioBackend (AudioEngine& e, AudioBackendInfo& info)
        , _input_audio_device("")
        , _output_audio_device("")
        , _midi_driver_option(get_standard_device_name(DeviceNone))
-       , _device_reservation(0)
        , _samplerate (48000)
        , _samples_per_period (1024)
        , _periods_per_cycle (2)
@@ -142,83 +141,6 @@ AlsaAudioBackend::enumerate_output_devices () const
        return _output_audio_device_status;
 }
 
-void
-AlsaAudioBackend::reservation_stdout (std::string d, size_t /* s */)
-{
-  if (d.substr(0, 19) == "Acquired audio-card") {
-               _reservation_succeeded = true;
-       }
-}
-
-void
-AlsaAudioBackend::release_device()
-{
-       _reservation_connection.drop_connections();
-       ARDOUR::SystemExec * tmp = _device_reservation;
-       _device_reservation = 0;
-       delete tmp;
-}
-
-bool
-AlsaAudioBackend::acquire_device(const char* device_name)
-{
-       /* This is  quick hack, ideally we'll link against libdbus and implement a dbus-listener
-        * that owns the device. here we try to get away by just requesting it and then block it...
-        * (pulseaudio periodically checks anyway)
-        *
-        * dbus-send --session --print-reply --type=method_call --dest=org.freedesktop.ReserveDevice1.Audio2 /org/freedesktop/ReserveDevice1/Audio2 org.freedesktop.ReserveDevice1.RequestRelease int32:4
-        * -> should not return  'boolean false'
-        */
-       int device_number = card_to_num(device_name);
-       if (device_number < 0) return false;
-
-       assert(_device_reservation == 0);
-       _reservation_succeeded = false;
-
-       std::string request_device_exe;
-       if (!PBD::find_file (
-                               PBD::Searchpath(Glib::build_filename(ARDOUR::ardour_dll_directory(), "ardouralsautil")
-                                       + G_SEARCHPATH_SEPARATOR_S + ARDOUR::ardour_dll_directory()),
-                               "ardour-request-device", request_device_exe))
-       {
-               PBD::warning << "ardour-request-device binary was not found..'" << endmsg;
-               return false;
-       }
-       else
-       {
-               char **argp;
-               char tmp[128];
-               argp=(char**) calloc(5,sizeof(char*));
-               argp[0] = strdup(request_device_exe.c_str());
-               argp[1] = strdup("-P");
-               snprintf(tmp, sizeof(tmp), "%d", getpid());
-               argp[2] = strdup(tmp);
-               snprintf(tmp, sizeof(tmp), "Audio%d", device_number);
-               argp[3] = strdup(tmp);
-               argp[4] = 0;
-
-               _device_reservation = new ARDOUR::SystemExec(request_device_exe, argp);
-               _device_reservation->ReadStdout.connect_same_thread (_reservation_connection, boost::bind (&AlsaAudioBackend::reservation_stdout, this, _1 ,_2));
-               _device_reservation->Terminated.connect_same_thread (_reservation_connection, boost::bind (&AlsaAudioBackend::release_device, this));
-               if (_device_reservation->start(0)) {
-                       PBD::warning << _("AlsaAudioBackend: Device Request failed.") << endmsg;
-                       release_device();
-                       return false;
-               }
-       }
-       // wait to check if reservation suceeded.
-       int timeout = 500; // 5 sec
-       while (_device_reservation && !_reservation_succeeded && --timeout > 0) {
-               Glib::usleep(10000);
-       }
-       if (timeout == 0 || !_reservation_succeeded) {
-               PBD::warning << _("AlsaAudioBackend: Device Reservation failed.") << endmsg;
-               release_device();
-               return false;
-       }
-       return true;
-}
-
 std::vector<float>
 AlsaAudioBackend::available_sample_rates2 (const std::string& input_device, const std::string& output_device) const
 {
@@ -834,7 +756,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
        _freewheel = false;
        _last_process_start = 0;
 
-       release_device();
+       _device_reservation.release_device();
 
        assert(_rmidi_in.size() == 0);
        assert(_rmidi_out.size() == 0);
@@ -881,7 +803,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
                return AudioDeviceNotAvailableError;
        }
 
-       acquire_device(alsa_device.c_str());
+       _device_reservation.acquire_device(alsa_device.c_str());
        _pcmi = new Alsa_pcmi (
                        (duplex & 2) ? alsa_device.c_str() : NULL,
                        (duplex & 1) ? alsa_device.c_str() : NULL,
@@ -929,7 +851,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
 
        if (_pcmi->state ()) {
                delete _pcmi; _pcmi = 0;
-               release_device();
+               _device_reservation.release_device();
                return error_code;
        }
 
@@ -974,7 +896,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
        if (register_system_audio_ports()) {
                PBD::error << _("AlsaAudioBackend: failed to register system ports.") << endmsg;
                delete _pcmi; _pcmi = 0;
-               release_device();
+               _device_reservation.release_device();
                return PortRegistrationError;
        }
 
@@ -984,7 +906,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
        if (engine.reestablish_ports ()) {
                PBD::error << _("AlsaAudioBackend: Could not re-establish ports.") << endmsg;
                delete _pcmi; _pcmi = 0;
-               release_device();
+               _device_reservation.release_device();
                return PortReconnectError;
        }
 
@@ -999,7 +921,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
                {
                        PBD::error << _("AlsaAudioBackend: failed to create process thread.") << endmsg;
                        delete _pcmi; _pcmi = 0;
-                       release_device();
+                       _device_reservation.release_device();
                        _run = false;
                        return ProcessThreadStartError;
                } else {
@@ -1013,7 +935,7 @@ AlsaAudioBackend::_start (bool for_latency_measurement)
        if (timeout == 0 || !_active) {
                PBD::error << _("AlsaAudioBackend: failed to start process thread.") << endmsg;
                delete _pcmi; _pcmi = 0;
-               release_device();
+               _device_reservation.release_device();
                _run = false;
                return ProcessThreadStartError;
        }
@@ -1051,7 +973,7 @@ AlsaAudioBackend::stop ()
        unregister_ports();
        delete _pcmi; _pcmi = 0;
        _midi_ins = _midi_outs = 0;
-       release_device();
+       _device_reservation.release_device();
        _measure_latency = false;
 
        return (_active == false) ? 0 : -1;
@@ -2377,3 +2299,91 @@ AlsaMidiEvent::AlsaMidiEvent (const AlsaMidiEvent& other)
                memcpy (_data, other._data, other._size);
        }
 };
+
+/******************************************************************************/
+
+AlsaDeviceReservation::AlsaDeviceReservation ()
+       : _device_reservation (0)
+{}
+
+AlsaDeviceReservation::AlsaDeviceReservation (const char* device_name)
+       : _device_reservation (0)
+{
+       acquire_device (device_name);
+}
+
+AlsaDeviceReservation::~AlsaDeviceReservation ()
+{
+       release_device ();
+}
+
+bool
+AlsaDeviceReservation::acquire_device (const char* device_name)
+{
+       int device_number = card_to_num(device_name);
+       if (device_number < 0) return false;
+
+       assert(_device_reservation == 0);
+       _reservation_succeeded = false;
+
+       std::string request_device_exe;
+       if (!PBD::find_file (
+                               PBD::Searchpath(Glib::build_filename(ARDOUR::ardour_dll_directory(), "ardouralsautil")
+                                       + G_SEARCHPATH_SEPARATOR_S + ARDOUR::ardour_dll_directory()),
+                               "ardour-request-device", request_device_exe))
+       {
+               PBD::warning << "ardour-request-device binary was not found..'" << endmsg;
+               return false;
+       }
+
+       char **argp;
+       char tmp[128];
+       argp=(char**) calloc(5,sizeof(char*));
+       argp[0] = strdup(request_device_exe.c_str());
+       argp[1] = strdup("-P");
+       snprintf(tmp, sizeof(tmp), "%d", getpid());
+       argp[2] = strdup(tmp);
+       snprintf(tmp, sizeof(tmp), "Audio%d", device_number);
+       argp[3] = strdup(tmp);
+       argp[4] = 0;
+
+       _device_reservation = new ARDOUR::SystemExec(request_device_exe, argp);
+       _device_reservation->ReadStdout.connect_same_thread (_reservation_connection, boost::bind (&AlsaDeviceReservation::reservation_stdout, this, _1 ,_2));
+       _device_reservation->Terminated.connect_same_thread (_reservation_connection, boost::bind (&AlsaDeviceReservation::release_device, this));
+
+       if (_device_reservation->start(0)) {
+               PBD::warning << _("AlsaAudioBackend: Device Request failed.") << endmsg;
+               release_device();
+               return false;
+       }
+
+       /* wait to check if reservation suceeded. */
+       int timeout = 500; // 5 sec
+       while (_device_reservation && !_reservation_succeeded && --timeout > 0) {
+               Glib::usleep(10000);
+       }
+
+       if (timeout == 0 || !_reservation_succeeded) {
+               PBD::warning << _("AlsaAudioBackend: Device Reservation failed.") << endmsg;
+               release_device();
+               return false;
+       }
+       return true;
+}
+
+void
+AlsaDeviceReservation::release_device ()
+{
+       _reservation_connection.drop_connections();
+       ARDOUR::SystemExec* tmp = _device_reservation;
+       _device_reservation = 0;
+       delete tmp;
+}
+
+void
+AlsaDeviceReservation::reservation_stdout (std::string d, size_t /* s */)
+{
+  if (d.substr(0, 19) == "Acquired audio-card") {
+               _reservation_succeeded = true;
+       }
+}

diff --git a/libs/backends/alsa/alsa_audiobackend.h b/libs/backends/alsa/alsa_audiobackend.h
index c175a1950b3e8abc0103c76e4dacd83841750182..e90bec5df9daeffa2dd2deae25c77581a0b940bf 100644 (file)
--- a/libs/backends/alsa/alsa_audiobackend.h
+++ b/libs/backends/alsa/alsa_audiobackend.h
@@ -158,6 +158,23 @@ class AlsaMidiPort : public AlsaPort {
                int _bufperiod;
 }; // class AlsaMidiPort
 
+class AlsaDeviceReservation
+{
+       public:
+               AlsaDeviceReservation ();
+               AlsaDeviceReservation (const char* device_name);
+               ~AlsaDeviceReservation ();
+
+               bool acquire_device (const char* device_name);
+               void release_device ();
+
+       private:
+               ARDOUR::SystemExec* _device_reservation;
+               PBD::ScopedConnectionList _reservation_connection;
+               void reservation_stdout (std::string, size_t);
+               bool _reservation_succeeded;
+};
+
 class AlsaAudioBackend : public AudioBackend {
        friend class AlsaPort;
        public:
@@ -345,12 +362,7 @@ class AlsaAudioBackend : public AudioBackend {
                std::string _midi_driver_option;
 
                /* audio device reservation */
-               ARDOUR::SystemExec *_device_reservation;
-               PBD::ScopedConnectionList _reservation_connection;
-               void reservation_stdout (std::string, size_t);
-               bool acquire_device(const char* device_name);
-               void release_device();
-               bool _reservation_succeeded;
+               AlsaDeviceReservation _device_reservation;
 
                /* audio settings */
                float  _samplerate;