jack.c 18 KB

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  1. /**
  2. * OpenAL cross platform audio library
  3. * Copyright (C) 1999-2007 by authors.
  4. * This library is free software; you can redistribute it and/or
  5. * modify it under the terms of the GNU Library General Public
  6. * License as published by the Free Software Foundation; either
  7. * version 2 of the License, or (at your option) any later version.
  8. *
  9. * This library 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 GNU
  12. * Library General Public License for more details.
  13. *
  14. * You should have received a copy of the GNU Library General Public
  15. * License along with this library; if not, write to the
  16. * Free Software Foundation, Inc.,
  17. * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18. * Or go to http://www.gnu.org/copyleft/lgpl.html
  19. */
  20. #include "config.h"
  21. #include <stdlib.h>
  22. #include <stdio.h>
  23. #include <memory.h>
  24. #include "alMain.h"
  25. #include "alu.h"
  26. #include "threads.h"
  27. #include "compat.h"
  28. #include "backends/base.h"
  29. #include <jack/jack.h>
  30. #include <jack/ringbuffer.h>
  31. static const ALCchar jackDevice[] = "JACK Default";
  32. #ifdef HAVE_DYNLOAD
  33. #define JACK_FUNCS(MAGIC) \
  34. MAGIC(jack_client_open); \
  35. MAGIC(jack_client_close); \
  36. MAGIC(jack_client_name_size); \
  37. MAGIC(jack_get_client_name); \
  38. MAGIC(jack_connect); \
  39. MAGIC(jack_activate); \
  40. MAGIC(jack_deactivate); \
  41. MAGIC(jack_port_register); \
  42. MAGIC(jack_port_unregister); \
  43. MAGIC(jack_port_get_buffer); \
  44. MAGIC(jack_port_name); \
  45. MAGIC(jack_get_ports); \
  46. MAGIC(jack_free); \
  47. MAGIC(jack_get_sample_rate); \
  48. MAGIC(jack_set_error_function); \
  49. MAGIC(jack_set_process_callback); \
  50. MAGIC(jack_set_buffer_size_callback); \
  51. MAGIC(jack_set_buffer_size); \
  52. MAGIC(jack_get_buffer_size);
  53. static void *jack_handle;
  54. #define MAKE_FUNC(f) static __typeof(f) * p##f
  55. JACK_FUNCS(MAKE_FUNC);
  56. #undef MAKE_FUNC
  57. #define jack_client_open pjack_client_open
  58. #define jack_client_close pjack_client_close
  59. #define jack_client_name_size pjack_client_name_size
  60. #define jack_get_client_name pjack_get_client_name
  61. #define jack_connect pjack_connect
  62. #define jack_activate pjack_activate
  63. #define jack_deactivate pjack_deactivate
  64. #define jack_port_register pjack_port_register
  65. #define jack_port_unregister pjack_port_unregister
  66. #define jack_port_get_buffer pjack_port_get_buffer
  67. #define jack_port_name pjack_port_name
  68. #define jack_get_ports pjack_get_ports
  69. #define jack_free pjack_free
  70. #define jack_get_sample_rate pjack_get_sample_rate
  71. #define jack_set_error_function pjack_set_error_function
  72. #define jack_set_process_callback pjack_set_process_callback
  73. #define jack_set_buffer_size_callback pjack_set_buffer_size_callback
  74. #define jack_set_buffer_size pjack_set_buffer_size
  75. #define jack_get_buffer_size pjack_get_buffer_size
  76. #endif
  77. static jack_options_t ClientOptions = JackNullOption;
  78. static ALCboolean jack_load(void)
  79. {
  80. ALCboolean error = ALC_FALSE;
  81. #ifdef HAVE_DYNLOAD
  82. if(!jack_handle)
  83. {
  84. #ifdef _WIN32
  85. #define JACKLIB "libjack.dll"
  86. #else
  87. #define JACKLIB "libjack.so.0"
  88. #endif
  89. jack_handle = LoadLib(JACKLIB);
  90. if(!jack_handle)
  91. return ALC_FALSE;
  92. error = ALC_FALSE;
  93. #define LOAD_FUNC(f) do { \
  94. p##f = GetSymbol(jack_handle, #f); \
  95. if(p##f == NULL) { \
  96. error = ALC_TRUE; \
  97. } \
  98. } while(0)
  99. JACK_FUNCS(LOAD_FUNC);
  100. #undef LOAD_FUNC
  101. if(error)
  102. {
  103. CloseLib(jack_handle);
  104. jack_handle = NULL;
  105. return ALC_FALSE;
  106. }
  107. }
  108. #endif
  109. return !error;
  110. }
  111. typedef struct ALCjackPlayback {
  112. DERIVE_FROM_TYPE(ALCbackend);
  113. jack_client_t *Client;
  114. jack_port_t *Port[MAX_OUTPUT_CHANNELS];
  115. ll_ringbuffer_t *Ring;
  116. alcnd_t Cond;
  117. volatile int killNow;
  118. althrd_t thread;
  119. } ALCjackPlayback;
  120. static int ALCjackPlayback_bufferSizeNotify(jack_nframes_t numframes, void *arg);
  121. static int ALCjackPlayback_process(jack_nframes_t numframes, void *arg);
  122. static int ALCjackPlayback_mixerProc(void *arg);
  123. static void ALCjackPlayback_Construct(ALCjackPlayback *self, ALCdevice *device);
  124. static void ALCjackPlayback_Destruct(ALCjackPlayback *self);
  125. static ALCenum ALCjackPlayback_open(ALCjackPlayback *self, const ALCchar *name);
  126. static void ALCjackPlayback_close(ALCjackPlayback *self);
  127. static ALCboolean ALCjackPlayback_reset(ALCjackPlayback *self);
  128. static ALCboolean ALCjackPlayback_start(ALCjackPlayback *self);
  129. static void ALCjackPlayback_stop(ALCjackPlayback *self);
  130. static DECLARE_FORWARD2(ALCjackPlayback, ALCbackend, ALCenum, captureSamples, void*, ALCuint)
  131. static DECLARE_FORWARD(ALCjackPlayback, ALCbackend, ALCuint, availableSamples)
  132. static ClockLatency ALCjackPlayback_getClockLatency(ALCjackPlayback *self);
  133. static void ALCjackPlayback_lock(ALCjackPlayback *self);
  134. static void ALCjackPlayback_unlock(ALCjackPlayback *self);
  135. DECLARE_DEFAULT_ALLOCATORS(ALCjackPlayback)
  136. DEFINE_ALCBACKEND_VTABLE(ALCjackPlayback);
  137. static void ALCjackPlayback_Construct(ALCjackPlayback *self, ALCdevice *device)
  138. {
  139. ALuint i;
  140. ALCbackend_Construct(STATIC_CAST(ALCbackend, self), device);
  141. SET_VTABLE2(ALCjackPlayback, ALCbackend, self);
  142. alcnd_init(&self->Cond);
  143. self->Client = NULL;
  144. for(i = 0;i < MAX_OUTPUT_CHANNELS;i++)
  145. self->Port[i] = NULL;
  146. self->Ring = NULL;
  147. self->killNow = 1;
  148. }
  149. static void ALCjackPlayback_Destruct(ALCjackPlayback *self)
  150. {
  151. ALuint i;
  152. if(self->Client)
  153. {
  154. for(i = 0;i < MAX_OUTPUT_CHANNELS;i++)
  155. {
  156. if(self->Port[i])
  157. jack_port_unregister(self->Client, self->Port[i]);
  158. self->Port[i] = NULL;
  159. }
  160. jack_client_close(self->Client);
  161. self->Client = NULL;
  162. }
  163. alcnd_destroy(&self->Cond);
  164. ALCbackend_Destruct(STATIC_CAST(ALCbackend, self));
  165. }
  166. static int ALCjackPlayback_bufferSizeNotify(jack_nframes_t numframes, void *arg)
  167. {
  168. ALCjackPlayback *self = arg;
  169. ALCdevice *device = STATIC_CAST(ALCbackend,self)->mDevice;
  170. ALuint bufsize;
  171. ALCjackPlayback_lock(self);
  172. device->UpdateSize = numframes;
  173. device->NumUpdates = 2;
  174. TRACE("%u update size x%u\n", device->UpdateSize, device->NumUpdates);
  175. bufsize = device->UpdateSize;
  176. if(ConfigValueUInt(al_string_get_cstr(device->DeviceName), "jack", "buffer-size", &bufsize))
  177. bufsize = maxu(NextPowerOf2(bufsize), device->UpdateSize);
  178. bufsize += device->UpdateSize;
  179. ll_ringbuffer_free(self->Ring);
  180. self->Ring = ll_ringbuffer_create(bufsize, FrameSizeFromDevFmt(device->FmtChans, device->FmtType));
  181. if(!self->Ring)
  182. {
  183. ERR("Failed to reallocate ringbuffer\n");
  184. aluHandleDisconnect(device);
  185. }
  186. ALCjackPlayback_unlock(self);
  187. return 0;
  188. }
  189. static int ALCjackPlayback_process(jack_nframes_t numframes, void *arg)
  190. {
  191. ALCjackPlayback *self = arg;
  192. jack_default_audio_sample_t *out[MAX_OUTPUT_CHANNELS];
  193. ll_ringbuffer_data_t data[2];
  194. jack_nframes_t total = 0;
  195. jack_nframes_t todo;
  196. ALuint i, c, numchans;
  197. ll_ringbuffer_get_read_vector(self->Ring, data);
  198. for(c = 0;c < MAX_OUTPUT_CHANNELS && self->Port[c];c++)
  199. out[c] = jack_port_get_buffer(self->Port[c], numframes);
  200. numchans = c;
  201. todo = minu(numframes, data[0].len);
  202. for(c = 0;c < numchans;c++)
  203. {
  204. for(i = 0;i < todo;i++)
  205. out[c][i] = ((ALfloat*)data[0].buf)[i*numchans + c];
  206. out[c] += todo;
  207. }
  208. total += todo;
  209. todo = minu(numframes-total, data[1].len);
  210. if(todo > 0)
  211. {
  212. for(c = 0;c < numchans;c++)
  213. {
  214. for(i = 0;i < todo;i++)
  215. out[c][i] = ((ALfloat*)data[1].buf)[i*numchans + c];
  216. out[c] += todo;
  217. }
  218. total += todo;
  219. }
  220. ll_ringbuffer_read_advance(self->Ring, total);
  221. alcnd_signal(&self->Cond);
  222. if(numframes > total)
  223. {
  224. todo = numframes-total;
  225. for(c = 0;c < numchans;c++)
  226. {
  227. for(i = 0;i < todo;i++)
  228. out[c][i] = 0.0f;
  229. }
  230. }
  231. return 0;
  232. }
  233. static int ALCjackPlayback_mixerProc(void *arg)
  234. {
  235. ALCjackPlayback *self = arg;
  236. ALCdevice *device = STATIC_CAST(ALCbackend,self)->mDevice;
  237. ll_ringbuffer_data_t data[2];
  238. SetRTPriority();
  239. althrd_setname(althrd_current(), MIXER_THREAD_NAME);
  240. ALCjackPlayback_lock(self);
  241. while(!self->killNow && device->Connected)
  242. {
  243. ALuint todo, len1, len2;
  244. /* NOTE: Unfortunately, there is an unavoidable race condition here.
  245. * It's possible for the process() method to run, updating the read
  246. * pointer and signaling the condition variable, in between the mixer
  247. * loop checking the write size and waiting for the condition variable.
  248. * This will cause the mixer loop to wait until the *next* process()
  249. * invocation, most likely writing silence for it.
  250. *
  251. * However, this should only happen if the mixer is running behind
  252. * anyway (as ideally we'll be asleep in alcnd_wait by the time the
  253. * process() method is invoked), so this behavior is not unwarranted.
  254. * It's unfortunate since it'll be wasting time sleeping that could be
  255. * used to catch up, but there's no way around it without blocking in
  256. * the process() method.
  257. */
  258. if(ll_ringbuffer_write_space(self->Ring) < device->UpdateSize)
  259. {
  260. alcnd_wait(&self->Cond, &STATIC_CAST(ALCbackend,self)->mMutex);
  261. continue;
  262. }
  263. ll_ringbuffer_get_write_vector(self->Ring, data);
  264. todo = data[0].len + data[1].len;
  265. todo -= todo%device->UpdateSize;
  266. len1 = minu(data[0].len, todo);
  267. len2 = minu(data[1].len, todo-len1);
  268. aluMixData(device, data[0].buf, len1);
  269. if(len2 > 0)
  270. aluMixData(device, data[1].buf, len2);
  271. ll_ringbuffer_write_advance(self->Ring, todo);
  272. }
  273. ALCjackPlayback_unlock(self);
  274. return 0;
  275. }
  276. static ALCenum ALCjackPlayback_open(ALCjackPlayback *self, const ALCchar *name)
  277. {
  278. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  279. const char *client_name = "alsoft";
  280. jack_status_t status;
  281. if(!name)
  282. name = jackDevice;
  283. else if(strcmp(name, jackDevice) != 0)
  284. return ALC_INVALID_VALUE;
  285. self->Client = jack_client_open(client_name, ClientOptions, &status, NULL);
  286. if(self->Client == NULL)
  287. {
  288. ERR("jack_client_open() failed, status = 0x%02x\n", status);
  289. return ALC_INVALID_VALUE;
  290. }
  291. if((status&JackServerStarted))
  292. TRACE("JACK server started\n");
  293. if((status&JackNameNotUnique))
  294. {
  295. client_name = jack_get_client_name(self->Client);
  296. TRACE("Client name not unique, got `%s' instead\n", client_name);
  297. }
  298. jack_set_process_callback(self->Client, ALCjackPlayback_process, self);
  299. jack_set_buffer_size_callback(self->Client, ALCjackPlayback_bufferSizeNotify, self);
  300. al_string_copy_cstr(&device->DeviceName, name);
  301. return ALC_NO_ERROR;
  302. }
  303. static void ALCjackPlayback_close(ALCjackPlayback *self)
  304. {
  305. ALuint i;
  306. for(i = 0;i < MAX_OUTPUT_CHANNELS;i++)
  307. {
  308. if(self->Port[i])
  309. jack_port_unregister(self->Client, self->Port[i]);
  310. self->Port[i] = NULL;
  311. }
  312. jack_client_close(self->Client);
  313. self->Client = NULL;
  314. }
  315. static ALCboolean ALCjackPlayback_reset(ALCjackPlayback *self)
  316. {
  317. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  318. ALuint numchans, i;
  319. ALuint bufsize;
  320. for(i = 0;i < MAX_OUTPUT_CHANNELS;i++)
  321. {
  322. if(self->Port[i])
  323. jack_port_unregister(self->Client, self->Port[i]);
  324. self->Port[i] = NULL;
  325. }
  326. /* Ignore the requested buffer metrics and just keep one JACK-sized buffer
  327. * ready for when requested. Note that one period's worth of audio in the
  328. * ring buffer will always be left unfilled because one element of the ring
  329. * buffer will not be writeable, and we only write in period-sized chunks.
  330. */
  331. device->Frequency = jack_get_sample_rate(self->Client);
  332. device->UpdateSize = jack_get_buffer_size(self->Client);
  333. device->NumUpdates = 2;
  334. bufsize = device->UpdateSize;
  335. if(ConfigValueUInt(al_string_get_cstr(device->DeviceName), "jack", "buffer-size", &bufsize))
  336. bufsize = maxu(NextPowerOf2(bufsize), device->UpdateSize);
  337. bufsize += device->UpdateSize;
  338. /* Force 32-bit float output. */
  339. device->FmtType = DevFmtFloat;
  340. numchans = ChannelsFromDevFmt(device->FmtChans);
  341. for(i = 0;i < numchans;i++)
  342. {
  343. char name[64];
  344. snprintf(name, sizeof(name), "channel_%d", i+1);
  345. self->Port[i] = jack_port_register(self->Client, name, JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0);
  346. if(self->Port[i] == NULL)
  347. {
  348. ERR("Not enough JACK ports available for %s output\n", DevFmtChannelsString(device->FmtChans));
  349. if(i == 0) return ALC_FALSE;
  350. break;
  351. }
  352. }
  353. if(i < numchans)
  354. {
  355. if(i == 1)
  356. device->FmtChans = DevFmtMono;
  357. else
  358. {
  359. for(--i;i >= 2;i--)
  360. {
  361. jack_port_unregister(self->Client, self->Port[i]);
  362. self->Port[i] = NULL;
  363. }
  364. device->FmtChans = DevFmtStereo;
  365. }
  366. }
  367. ll_ringbuffer_free(self->Ring);
  368. self->Ring = ll_ringbuffer_create(bufsize, FrameSizeFromDevFmt(device->FmtChans, device->FmtType));
  369. if(!self->Ring)
  370. {
  371. ERR("Failed to allocate ringbuffer\n");
  372. return ALC_FALSE;
  373. }
  374. SetDefaultChannelOrder(device);
  375. return ALC_TRUE;
  376. }
  377. static ALCboolean ALCjackPlayback_start(ALCjackPlayback *self)
  378. {
  379. const char **ports;
  380. ALuint i;
  381. if(jack_activate(self->Client))
  382. {
  383. ERR("Failed to activate client\n");
  384. return ALC_FALSE;
  385. }
  386. ports = jack_get_ports(self->Client, NULL, NULL, JackPortIsPhysical|JackPortIsInput);
  387. if(ports == NULL)
  388. {
  389. ERR("No physical playback ports found\n");
  390. jack_deactivate(self->Client);
  391. return ALC_FALSE;
  392. }
  393. for(i = 0;i < MAX_OUTPUT_CHANNELS && self->Port[i];i++)
  394. {
  395. if(!ports[i])
  396. {
  397. ERR("No physical playback port for \"%s\"\n", jack_port_name(self->Port[i]));
  398. break;
  399. }
  400. if(jack_connect(self->Client, jack_port_name(self->Port[i]), ports[i]))
  401. ERR("Failed to connect output port \"%s\" to \"%s\"\n", jack_port_name(self->Port[i]), ports[i]);
  402. }
  403. jack_free(ports);
  404. self->killNow = 0;
  405. if(althrd_create(&self->thread, ALCjackPlayback_mixerProc, self) != althrd_success)
  406. {
  407. jack_deactivate(self->Client);
  408. return ALC_FALSE;
  409. }
  410. return ALC_TRUE;
  411. }
  412. static void ALCjackPlayback_stop(ALCjackPlayback *self)
  413. {
  414. int res;
  415. if(self->killNow)
  416. return;
  417. self->killNow = 1;
  418. /* Lock the backend to ensure we don't flag the mixer to die and signal the
  419. * mixer to wake up in between it checking the flag and going to sleep and
  420. * wait for a wakeup (potentially leading to it never waking back up to see
  421. * the flag). */
  422. ALCjackPlayback_lock(self);
  423. ALCjackPlayback_unlock(self);
  424. alcnd_signal(&self->Cond);
  425. althrd_join(self->thread, &res);
  426. jack_deactivate(self->Client);
  427. }
  428. static ClockLatency ALCjackPlayback_getClockLatency(ALCjackPlayback *self)
  429. {
  430. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  431. ClockLatency ret;
  432. ALCjackPlayback_lock(self);
  433. ret.ClockTime = GetDeviceClockTime(device);
  434. ret.Latency = ll_ringbuffer_read_space(self->Ring) * DEVICE_CLOCK_RES /
  435. device->Frequency;
  436. ALCjackPlayback_unlock(self);
  437. return ret;
  438. }
  439. static void ALCjackPlayback_lock(ALCjackPlayback *self)
  440. {
  441. almtx_lock(&STATIC_CAST(ALCbackend,self)->mMutex);
  442. }
  443. static void ALCjackPlayback_unlock(ALCjackPlayback *self)
  444. {
  445. almtx_unlock(&STATIC_CAST(ALCbackend,self)->mMutex);
  446. }
  447. static void jack_msg_handler(const char *message)
  448. {
  449. WARN("%s\n", message);
  450. }
  451. typedef struct ALCjackBackendFactory {
  452. DERIVE_FROM_TYPE(ALCbackendFactory);
  453. } ALCjackBackendFactory;
  454. #define ALCJACKBACKENDFACTORY_INITIALIZER { { GET_VTABLE2(ALCjackBackendFactory, ALCbackendFactory) } }
  455. static ALCboolean ALCjackBackendFactory_init(ALCjackBackendFactory* UNUSED(self))
  456. {
  457. jack_client_t *client;
  458. jack_status_t status;
  459. if(!jack_load())
  460. return ALC_FALSE;
  461. if(!GetConfigValueBool(NULL, "jack", "spawn-server", 0))
  462. ClientOptions |= JackNoStartServer;
  463. jack_set_error_function(jack_msg_handler);
  464. client = jack_client_open("alsoft", ClientOptions, &status, NULL);
  465. jack_set_error_function(NULL);
  466. if(client == NULL)
  467. {
  468. WARN("jack_client_open() failed, 0x%02x\n", status);
  469. if((status&JackServerFailed) && !(ClientOptions&JackNoStartServer))
  470. ERR("Unable to connect to JACK server\n");
  471. return ALC_FALSE;
  472. }
  473. jack_client_close(client);
  474. return ALC_TRUE;
  475. }
  476. static void ALCjackBackendFactory_deinit(ALCjackBackendFactory* UNUSED(self))
  477. {
  478. #ifdef HAVE_DYNLOAD
  479. if(jack_handle)
  480. CloseLib(jack_handle);
  481. jack_handle = NULL;
  482. #endif
  483. }
  484. static ALCboolean ALCjackBackendFactory_querySupport(ALCjackBackendFactory* UNUSED(self), ALCbackend_Type type)
  485. {
  486. if(type == ALCbackend_Playback)
  487. return ALC_TRUE;
  488. return ALC_FALSE;
  489. }
  490. static void ALCjackBackendFactory_probe(ALCjackBackendFactory* UNUSED(self), enum DevProbe type)
  491. {
  492. switch(type)
  493. {
  494. case ALL_DEVICE_PROBE:
  495. AppendAllDevicesList(jackDevice);
  496. break;
  497. case CAPTURE_DEVICE_PROBE:
  498. break;
  499. }
  500. }
  501. static ALCbackend* ALCjackBackendFactory_createBackend(ALCjackBackendFactory* UNUSED(self), ALCdevice *device, ALCbackend_Type type)
  502. {
  503. if(type == ALCbackend_Playback)
  504. {
  505. ALCjackPlayback *backend;
  506. NEW_OBJ(backend, ALCjackPlayback)(device);
  507. if(!backend) return NULL;
  508. return STATIC_CAST(ALCbackend, backend);
  509. }
  510. return NULL;
  511. }
  512. DEFINE_ALCBACKENDFACTORY_VTABLE(ALCjackBackendFactory);
  513. ALCbackendFactory *ALCjackBackendFactory_getFactory(void)
  514. {
  515. static ALCjackBackendFactory factory = ALCJACKBACKENDFACTORY_INITIALIZER;
  516. return STATIC_CAST(ALCbackendFactory, &factory);
  517. }