2 Copyright (C) 2002-2004 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 #ifndef __ardour_audioengine_h__
21 #define __ardour_audioengine_h__
24 #include "libardour-config.h"
34 #include <glibmm/threads.h>
36 #include "pbd/signals.h"
37 #include "pbd/stacktrace.h"
39 #include "ardour/ardour.h"
40 #include "ardour/data_type.h"
41 #include "ardour/session_handle.h"
42 #include "ardour/libardour_visibility.h"
43 #include "ardour/types.h"
44 #include "ardour/chan_count.h"
45 #include "ardour/port_manager.h"
58 struct AudioBackendInfo;
60 class LIBARDOUR_API AudioEngine : public PortManager, public SessionHandlePtr
64 static AudioEngine* create ();
66 virtual ~AudioEngine ();
68 int discover_backends();
69 std::vector<const AudioBackendInfo*> available_backends() const;
70 std::string current_backend_name () const;
71 boost::shared_ptr<AudioBackend> set_default_backend ();
72 boost::shared_ptr<AudioBackend> set_backend (const std::string&, const std::string& arg1, const std::string& arg2);
73 boost::shared_ptr<AudioBackend> current_backend() const { return _backend; }
74 bool setup_required () const;
76 ProcessThread* main_thread() const { return _main_thread; }
78 /* START BACKEND PROXY API
80 * See audio_backend.h for full documentation and semantics. These wrappers
81 * just forward to a backend implementation.
84 int start (bool for_latency_measurement=false);
85 int stop (bool for_latency_measurement=false);
86 int freewheel (bool start_stop);
87 float get_dsp_load() const ;
88 void transport_start ();
89 void transport_stop ();
90 TransportState transport_state ();
91 void transport_locate (samplepos_t pos);
92 samplepos_t transport_sample();
93 samplecnt_t sample_rate () const;
94 pframes_t samples_per_cycle () const;
95 int usecs_per_cycle () const;
96 size_t raw_buffer_size (DataType t);
97 samplepos_t sample_time ();
98 samplepos_t sample_time_at_cycle_start ();
99 pframes_t samples_since_cycle_start ();
100 bool get_sync_offset (pframes_t& offset) const;
102 std::string get_last_backend_error () const { return _last_backend_error_string; }
104 int create_process_thread (boost::function<void()> func);
105 int join_process_threads ();
106 bool in_process_thread ();
107 uint32_t process_thread_count ();
111 * -21 : additional I/O threads e.g. MIDI
112 * -22 : client/process threads
115 * - pbd_realtime_pthread_create
116 * - pbd_set_thread_priority
118 virtual int client_real_time_priority () { return -22; }
120 int backend_reset_requested();
121 void request_backend_reset();
122 void request_device_list_update();
123 void launch_device_control_app();
125 bool is_realtime() const;
126 bool connected() const;
128 // for the user which hold state_lock to check if reset operation is pending
129 bool is_reset_requested() const { return g_atomic_int_get(const_cast<gint*>(&_hw_reset_request_count)); }
131 int set_device_name (const std::string&);
132 int set_sample_rate (float);
133 int set_buffer_size (uint32_t);
134 int set_interleaved (bool yn);
135 int set_input_channels (uint32_t);
136 int set_output_channels (uint32_t);
137 int set_systemic_input_latency (uint32_t);
138 int set_systemic_output_latency (uint32_t);
140 /* END BACKEND PROXY API */
142 bool freewheeling() const { return _freewheeling; }
143 bool running() const { return _running; }
145 Glib::Threads::Mutex& process_lock() { return _process_lock; }
146 Glib::Threads::RecMutex& state_lock() { return _state_lock; }
148 int request_buffer_size (pframes_t samples) {
149 return set_buffer_size (samples);
152 samplecnt_t processed_samples() const { return _processed_samples; }
154 void set_session (Session *);
155 void remove_session (); // not a replacement for SessionHandle::session_going_away()
156 Session* session() const { return _session; }
158 void reconnect_session_routes (bool reconnect_inputs = true, bool reconnect_outputs = true);
160 class NoBackendAvailable : public std::exception {
162 virtual const char *what() const throw() { return "could not connect to engine backend"; }
165 void split_cycle (pframes_t offset);
167 int reset_timebase ();
169 void update_latencies ();
171 /* this signal is sent for every process() cycle while freewheeling.
172 (the regular process() call to session->process() is not made)
175 PBD::Signal1<void, pframes_t> Freewheel;
177 PBD::Signal0<void> Xrun;
179 /** this signal is emitted if the sample rate changes */
180 PBD::Signal1<void, samplecnt_t> SampleRateChanged;
182 /** this signal is emitted if the buffer size changes */
183 PBD::Signal1<void, pframes_t> BufferSizeChanged;
185 /** this signal is emitted if the device cannot operate properly */
186 PBD::Signal0<void> DeviceError;
188 /* this signal is emitted if the device list changed */
190 PBD::Signal0<void> DeviceListChanged;
192 /* this signal is sent if the backend ever disconnects us */
194 PBD::Signal1<void,const char*> Halted;
196 /* these two are emitted when the engine itself is
200 PBD::Signal0<void> Running;
201 PBD::Signal0<void> Stopped;
203 /* these two are emitted when a device reset is initiated/finished
206 PBD::Signal0<void> DeviceResetStarted;
207 PBD::Signal0<void> DeviceResetFinished;
209 static AudioEngine* instance() { return _instance; }
210 static void destroy();
213 /* The backend will cause these at the appropriate time(s)
215 int process_callback (pframes_t nframes);
216 int buffer_size_change (pframes_t nframes);
217 int sample_rate_change (pframes_t nframes);
218 void freewheel_callback (bool);
219 void timebase_callback (TransportState state, pframes_t nframes, samplepos_t pos, int new_position);
220 int sync_callback (TransportState state, samplepos_t position);
221 int port_registration_callback ();
222 void latency_callback (bool for_playback);
223 void halted_callback (const char* reason);
225 /* checks if current thread is properly set up for audio processing */
226 static bool thread_initialised_for_audio_processing ();
228 /* sets up the process callback thread */
229 static void thread_init_callback (void *);
231 /* latency measurement */
233 MTDM* mtdm() { return _mtdm; }
234 MIDIDM* mididm() { return _mididm; }
236 int prepare_for_latency_measurement ();
237 int start_latency_detection (bool);
238 void stop_latency_detection ();
239 void set_latency_input_port (const std::string&);
240 void set_latency_output_port (const std::string&);
241 uint32_t latency_signal_delay () const { return _latency_signal_latency; }
243 enum LatencyMeasurement {
249 LatencyMeasurement measuring_latency () const { return _measuring_latency; }
251 /* These two are used only in builds where SILENCE_AFTER_SECONDS was
252 * set. BecameSilent will be emitted when the audioengine goes silent.
253 * reset_silence_countdown() can be used to reset the silence
254 * countdown, whose duration will be reduced to half of its previous
258 PBD::Signal0<void> BecameSilent;
259 void reset_silence_countdown ();
261 void add_pending_port_deletion (Port*);
266 static AudioEngine* _instance;
268 Glib::Threads::Mutex _process_lock;
269 Glib::Threads::RecMutex _state_lock;
270 Glib::Threads::Cond session_removed;
271 bool session_remove_pending;
272 sampleoffset_t session_removal_countdown;
273 gain_t session_removal_gain;
274 gain_t session_removal_gain_step;
277 /// number of samples between each check for changes in monitor input
278 samplecnt_t monitor_check_interval;
279 /// time of the last monitor check in samples
280 samplecnt_t last_monitor_check;
281 /// the number of samples processed since start() was called
282 samplecnt_t _processed_samples;
283 Glib::Threads::Thread* m_meter_thread;
284 ProcessThread* _main_thread;
287 LatencyMeasurement _measuring_latency;
288 PortEngine::PortHandle _latency_input_port;
289 PortEngine::PortHandle _latency_output_port;
290 samplecnt_t _latency_flush_samples;
291 std::string _latency_input_name;
292 std::string _latency_output_name;
293 samplecnt_t _latency_signal_latency;
294 bool _stopped_for_latency;
295 bool _started_for_latency;
298 std::string _last_backend_error_string;
300 Glib::Threads::Thread* _hw_reset_event_thread;
301 gint _hw_reset_request_count;
302 Glib::Threads::Cond _hw_reset_condition;
303 Glib::Threads::Mutex _reset_request_lock;
304 gint _stop_hw_reset_processing;
305 Glib::Threads::Thread* _hw_devicelist_update_thread;
306 gint _hw_devicelist_update_count;
307 Glib::Threads::Cond _hw_devicelist_update_condition;
308 Glib::Threads::Mutex _devicelist_update_lock;
309 gint _stop_hw_devicelist_processing;
311 void start_hw_event_processing();
312 void stop_hw_event_processing();
313 void do_reset_backend();
314 void do_devicelist_update();
316 typedef std::map<std::string,AudioBackendInfo*> BackendMap;
317 BackendMap _backends;
318 AudioBackendInfo* backend_discover (const std::string&);
319 void drop_backend ();
322 samplecnt_t _silence_countdown;
323 uint32_t _silence_hit_cnt;
328 } // namespace ARDOUR
330 #endif /* __ardour_audioengine_h__ */