oss.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 <sys/ioctl.h>
  22. #include <sys/types.h>
  23. #include <sys/stat.h>
  24. #include <fcntl.h>
  25. #include <stdlib.h>
  26. #include <stdio.h>
  27. #include <memory.h>
  28. #include <unistd.h>
  29. #include <errno.h>
  30. #include <math.h>
  31. #include "alMain.h"
  32. #include "alu.h"
  33. #include "threads.h"
  34. #include "compat.h"
  35. #include "backends/base.h"
  36. #include <sys/soundcard.h>
  37. /*
  38. * The OSS documentation talks about SOUND_MIXER_READ, but the header
  39. * only contains MIXER_READ. Play safe. Same for WRITE.
  40. */
  41. #ifndef SOUND_MIXER_READ
  42. #define SOUND_MIXER_READ MIXER_READ
  43. #endif
  44. #ifndef SOUND_MIXER_WRITE
  45. #define SOUND_MIXER_WRITE MIXER_WRITE
  46. #endif
  47. static const ALCchar oss_device[] = "OSS Default";
  48. static const char *oss_driver = "/dev/dsp";
  49. static const char *oss_capture = "/dev/dsp";
  50. static int log2i(ALCuint x)
  51. {
  52. int y = 0;
  53. while (x > 1)
  54. {
  55. x >>= 1;
  56. y++;
  57. }
  58. return y;
  59. }
  60. typedef struct ALCplaybackOSS {
  61. DERIVE_FROM_TYPE(ALCbackend);
  62. int fd;
  63. ALubyte *mix_data;
  64. int data_size;
  65. volatile int killNow;
  66. althrd_t thread;
  67. } ALCplaybackOSS;
  68. static int ALCplaybackOSS_mixerProc(void *ptr);
  69. static void ALCplaybackOSS_Construct(ALCplaybackOSS *self, ALCdevice *device);
  70. static DECLARE_FORWARD(ALCplaybackOSS, ALCbackend, void, Destruct)
  71. static ALCenum ALCplaybackOSS_open(ALCplaybackOSS *self, const ALCchar *name);
  72. static void ALCplaybackOSS_close(ALCplaybackOSS *self);
  73. static ALCboolean ALCplaybackOSS_reset(ALCplaybackOSS *self);
  74. static ALCboolean ALCplaybackOSS_start(ALCplaybackOSS *self);
  75. static void ALCplaybackOSS_stop(ALCplaybackOSS *self);
  76. static DECLARE_FORWARD2(ALCplaybackOSS, ALCbackend, ALCenum, captureSamples, ALCvoid*, ALCuint)
  77. static DECLARE_FORWARD(ALCplaybackOSS, ALCbackend, ALCuint, availableSamples)
  78. static DECLARE_FORWARD(ALCplaybackOSS, ALCbackend, ALint64, getLatency)
  79. static DECLARE_FORWARD(ALCplaybackOSS, ALCbackend, void, lock)
  80. static DECLARE_FORWARD(ALCplaybackOSS, ALCbackend, void, unlock)
  81. DECLARE_DEFAULT_ALLOCATORS(ALCplaybackOSS)
  82. DEFINE_ALCBACKEND_VTABLE(ALCplaybackOSS);
  83. static int ALCplaybackOSS_mixerProc(void *ptr)
  84. {
  85. ALCplaybackOSS *self = (ALCplaybackOSS*)ptr;
  86. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  87. ALint frameSize;
  88. ssize_t wrote;
  89. SetRTPriority();
  90. althrd_setname(althrd_current(), MIXER_THREAD_NAME);
  91. frameSize = FrameSizeFromDevFmt(device->FmtChans, device->FmtType);
  92. while(!self->killNow && device->Connected)
  93. {
  94. ALint len = self->data_size;
  95. ALubyte *WritePtr = self->mix_data;
  96. aluMixData(device, WritePtr, len/frameSize);
  97. while(len > 0 && !self->killNow)
  98. {
  99. wrote = write(self->fd, WritePtr, len);
  100. if(wrote < 0)
  101. {
  102. if(errno != EAGAIN && errno != EWOULDBLOCK && errno != EINTR)
  103. {
  104. ERR("write failed: %s\n", strerror(errno));
  105. ALCplaybackOSS_lock(self);
  106. aluHandleDisconnect(device);
  107. ALCplaybackOSS_unlock(self);
  108. break;
  109. }
  110. al_nssleep(1000000);
  111. continue;
  112. }
  113. len -= wrote;
  114. WritePtr += wrote;
  115. }
  116. }
  117. return 0;
  118. }
  119. static void ALCplaybackOSS_Construct(ALCplaybackOSS *self, ALCdevice *device)
  120. {
  121. ALCbackend_Construct(STATIC_CAST(ALCbackend, self), device);
  122. SET_VTABLE2(ALCplaybackOSS, ALCbackend, self);
  123. }
  124. static ALCenum ALCplaybackOSS_open(ALCplaybackOSS *self, const ALCchar *name)
  125. {
  126. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  127. if(!name)
  128. name = oss_device;
  129. else if(strcmp(name, oss_device) != 0)
  130. return ALC_INVALID_VALUE;
  131. self->killNow = 0;
  132. self->fd = open(oss_driver, O_WRONLY);
  133. if(self->fd == -1)
  134. {
  135. ERR("Could not open %s: %s\n", oss_driver, strerror(errno));
  136. return ALC_INVALID_VALUE;
  137. }
  138. al_string_copy_cstr(&device->DeviceName, name);
  139. return ALC_NO_ERROR;
  140. }
  141. static void ALCplaybackOSS_close(ALCplaybackOSS *self)
  142. {
  143. close(self->fd);
  144. self->fd = -1;
  145. }
  146. static ALCboolean ALCplaybackOSS_reset(ALCplaybackOSS *self)
  147. {
  148. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  149. int numFragmentsLogSize;
  150. int log2FragmentSize;
  151. unsigned int periods;
  152. audio_buf_info info;
  153. ALuint frameSize;
  154. int numChannels;
  155. int ossFormat;
  156. int ossSpeed;
  157. char *err;
  158. switch(device->FmtType)
  159. {
  160. case DevFmtByte:
  161. ossFormat = AFMT_S8;
  162. break;
  163. case DevFmtUByte:
  164. ossFormat = AFMT_U8;
  165. break;
  166. case DevFmtUShort:
  167. case DevFmtInt:
  168. case DevFmtUInt:
  169. case DevFmtFloat:
  170. device->FmtType = DevFmtShort;
  171. /* fall-through */
  172. case DevFmtShort:
  173. ossFormat = AFMT_S16_NE;
  174. break;
  175. }
  176. periods = device->NumUpdates;
  177. numChannels = ChannelsFromDevFmt(device->FmtChans);
  178. frameSize = numChannels * BytesFromDevFmt(device->FmtType);
  179. ossSpeed = device->Frequency;
  180. log2FragmentSize = log2i(device->UpdateSize * frameSize);
  181. /* according to the OSS spec, 16 bytes are the minimum */
  182. if (log2FragmentSize < 4)
  183. log2FragmentSize = 4;
  184. /* Subtract one period since the temp mixing buffer counts as one. Still
  185. * need at least two on the card, though. */
  186. if(periods > 2) periods--;
  187. numFragmentsLogSize = (periods << 16) | log2FragmentSize;
  188. #define CHECKERR(func) if((func) < 0) { \
  189. err = #func; \
  190. goto err; \
  191. }
  192. /* Don't fail if SETFRAGMENT fails. We can handle just about anything
  193. * that's reported back via GETOSPACE */
  194. ioctl(self->fd, SNDCTL_DSP_SETFRAGMENT, &numFragmentsLogSize);
  195. CHECKERR(ioctl(self->fd, SNDCTL_DSP_SETFMT, &ossFormat));
  196. CHECKERR(ioctl(self->fd, SNDCTL_DSP_CHANNELS, &numChannels));
  197. CHECKERR(ioctl(self->fd, SNDCTL_DSP_SPEED, &ossSpeed));
  198. CHECKERR(ioctl(self->fd, SNDCTL_DSP_GETOSPACE, &info));
  199. if(0)
  200. {
  201. err:
  202. ERR("%s failed: %s\n", err, strerror(errno));
  203. return ALC_FALSE;
  204. }
  205. #undef CHECKERR
  206. if((int)ChannelsFromDevFmt(device->FmtChans) != numChannels)
  207. {
  208. ERR("Failed to set %s, got %d channels instead\n", DevFmtChannelsString(device->FmtChans), numChannels);
  209. return ALC_FALSE;
  210. }
  211. if(!((ossFormat == AFMT_S8 && device->FmtType == DevFmtByte) ||
  212. (ossFormat == AFMT_U8 && device->FmtType == DevFmtUByte) ||
  213. (ossFormat == AFMT_S16_NE && device->FmtType == DevFmtShort)))
  214. {
  215. ERR("Failed to set %s samples, got OSS format %#x\n", DevFmtTypeString(device->FmtType), ossFormat);
  216. return ALC_FALSE;
  217. }
  218. device->Frequency = ossSpeed;
  219. device->UpdateSize = info.fragsize / frameSize;
  220. device->NumUpdates = info.fragments + 1;
  221. SetDefaultChannelOrder(device);
  222. return ALC_TRUE;
  223. }
  224. static ALCboolean ALCplaybackOSS_start(ALCplaybackOSS *self)
  225. {
  226. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  227. self->data_size = device->UpdateSize * FrameSizeFromDevFmt(device->FmtChans, device->FmtType);
  228. self->mix_data = calloc(1, self->data_size);
  229. self->killNow = 0;
  230. if(althrd_create(&self->thread, ALCplaybackOSS_mixerProc, self) != althrd_success)
  231. {
  232. free(self->mix_data);
  233. self->mix_data = NULL;
  234. return ALC_FALSE;
  235. }
  236. return ALC_TRUE;
  237. }
  238. static void ALCplaybackOSS_stop(ALCplaybackOSS *self)
  239. {
  240. int res;
  241. if(self->killNow)
  242. return;
  243. self->killNow = 1;
  244. althrd_join(self->thread, &res);
  245. if(ioctl(self->fd, SNDCTL_DSP_RESET) != 0)
  246. ERR("Error resetting device: %s\n", strerror(errno));
  247. free(self->mix_data);
  248. self->mix_data = NULL;
  249. }
  250. typedef struct ALCcaptureOSS {
  251. DERIVE_FROM_TYPE(ALCbackend);
  252. int fd;
  253. ALubyte *read_data;
  254. int data_size;
  255. RingBuffer *ring;
  256. int doCapture;
  257. volatile int killNow;
  258. althrd_t thread;
  259. } ALCcaptureOSS;
  260. static int ALCcaptureOSS_recordProc(void *ptr);
  261. static void ALCcaptureOSS_Construct(ALCcaptureOSS *self, ALCdevice *device);
  262. static DECLARE_FORWARD(ALCcaptureOSS, ALCbackend, void, Destruct)
  263. static ALCenum ALCcaptureOSS_open(ALCcaptureOSS *self, const ALCchar *name);
  264. static void ALCcaptureOSS_close(ALCcaptureOSS *self);
  265. static DECLARE_FORWARD(ALCcaptureOSS, ALCbackend, ALCboolean, reset)
  266. static ALCboolean ALCcaptureOSS_start(ALCcaptureOSS *self);
  267. static void ALCcaptureOSS_stop(ALCcaptureOSS *self);
  268. static ALCenum ALCcaptureOSS_captureSamples(ALCcaptureOSS *self, ALCvoid *buffer, ALCuint samples);
  269. static ALCuint ALCcaptureOSS_availableSamples(ALCcaptureOSS *self);
  270. static DECLARE_FORWARD(ALCcaptureOSS, ALCbackend, ALint64, getLatency)
  271. static DECLARE_FORWARD(ALCcaptureOSS, ALCbackend, void, lock)
  272. static DECLARE_FORWARD(ALCcaptureOSS, ALCbackend, void, unlock)
  273. DECLARE_DEFAULT_ALLOCATORS(ALCcaptureOSS)
  274. DEFINE_ALCBACKEND_VTABLE(ALCcaptureOSS);
  275. static int ALCcaptureOSS_recordProc(void *ptr)
  276. {
  277. ALCcaptureOSS *self = (ALCcaptureOSS*)ptr;
  278. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  279. int frameSize;
  280. int amt;
  281. SetRTPriority();
  282. althrd_setname(althrd_current(), RECORD_THREAD_NAME);
  283. frameSize = FrameSizeFromDevFmt(device->FmtChans, device->FmtType);
  284. while(!self->killNow)
  285. {
  286. amt = read(self->fd, self->read_data, self->data_size);
  287. if(amt < 0)
  288. {
  289. ERR("read failed: %s\n", strerror(errno));
  290. ALCcaptureOSS_lock(self);
  291. aluHandleDisconnect(device);
  292. ALCcaptureOSS_unlock(self);
  293. break;
  294. }
  295. if(amt == 0)
  296. {
  297. al_nssleep(1000000);
  298. continue;
  299. }
  300. if(self->doCapture)
  301. WriteRingBuffer(self->ring, self->read_data, amt/frameSize);
  302. }
  303. return 0;
  304. }
  305. static void ALCcaptureOSS_Construct(ALCcaptureOSS *self, ALCdevice *device)
  306. {
  307. ALCbackend_Construct(STATIC_CAST(ALCbackend, self), device);
  308. SET_VTABLE2(ALCcaptureOSS, ALCbackend, self);
  309. }
  310. static ALCenum ALCcaptureOSS_open(ALCcaptureOSS *self, const ALCchar *name)
  311. {
  312. ALCdevice *device = STATIC_CAST(ALCbackend, self)->mDevice;
  313. int numFragmentsLogSize;
  314. int log2FragmentSize;
  315. unsigned int periods;
  316. audio_buf_info info;
  317. ALuint frameSize;
  318. int numChannels;
  319. int ossFormat;
  320. int ossSpeed;
  321. char *err;
  322. if(!name)
  323. name = oss_device;
  324. else if(strcmp(name, oss_device) != 0)
  325. return ALC_INVALID_VALUE;
  326. self->fd = open(oss_capture, O_RDONLY);
  327. if(self->fd == -1)
  328. {
  329. ERR("Could not open %s: %s\n", oss_capture, strerror(errno));
  330. return ALC_INVALID_VALUE;
  331. }
  332. switch(device->FmtType)
  333. {
  334. case DevFmtByte:
  335. ossFormat = AFMT_S8;
  336. break;
  337. case DevFmtUByte:
  338. ossFormat = AFMT_U8;
  339. break;
  340. case DevFmtShort:
  341. ossFormat = AFMT_S16_NE;
  342. break;
  343. case DevFmtUShort:
  344. case DevFmtInt:
  345. case DevFmtUInt:
  346. case DevFmtFloat:
  347. ERR("%s capture samples not supported\n", DevFmtTypeString(device->FmtType));
  348. return ALC_INVALID_VALUE;
  349. }
  350. periods = 4;
  351. numChannels = ChannelsFromDevFmt(device->FmtChans);
  352. frameSize = numChannels * BytesFromDevFmt(device->FmtType);
  353. ossSpeed = device->Frequency;
  354. log2FragmentSize = log2i(device->UpdateSize * device->NumUpdates *
  355. frameSize / periods);
  356. /* according to the OSS spec, 16 bytes are the minimum */
  357. if (log2FragmentSize < 4)
  358. log2FragmentSize = 4;
  359. numFragmentsLogSize = (periods << 16) | log2FragmentSize;
  360. #define CHECKERR(func) if((func) < 0) { \
  361. err = #func; \
  362. goto err; \
  363. }
  364. CHECKERR(ioctl(self->fd, SNDCTL_DSP_SETFRAGMENT, &numFragmentsLogSize));
  365. CHECKERR(ioctl(self->fd, SNDCTL_DSP_SETFMT, &ossFormat));
  366. CHECKERR(ioctl(self->fd, SNDCTL_DSP_CHANNELS, &numChannels));
  367. CHECKERR(ioctl(self->fd, SNDCTL_DSP_SPEED, &ossSpeed));
  368. CHECKERR(ioctl(self->fd, SNDCTL_DSP_GETISPACE, &info));
  369. if(0)
  370. {
  371. err:
  372. ERR("%s failed: %s\n", err, strerror(errno));
  373. close(self->fd);
  374. self->fd = -1;
  375. return ALC_INVALID_VALUE;
  376. }
  377. #undef CHECKERR
  378. if((int)ChannelsFromDevFmt(device->FmtChans) != numChannels)
  379. {
  380. ERR("Failed to set %s, got %d channels instead\n", DevFmtChannelsString(device->FmtChans), numChannels);
  381. close(self->fd);
  382. self->fd = -1;
  383. return ALC_INVALID_VALUE;
  384. }
  385. if(!((ossFormat == AFMT_S8 && device->FmtType == DevFmtByte) ||
  386. (ossFormat == AFMT_U8 && device->FmtType == DevFmtUByte) ||
  387. (ossFormat == AFMT_S16_NE && device->FmtType == DevFmtShort)))
  388. {
  389. ERR("Failed to set %s samples, got OSS format %#x\n", DevFmtTypeString(device->FmtType), ossFormat);
  390. close(self->fd);
  391. self->fd = -1;
  392. return ALC_INVALID_VALUE;
  393. }
  394. self->ring = CreateRingBuffer(frameSize, device->UpdateSize * device->NumUpdates);
  395. if(!self->ring)
  396. {
  397. ERR("Ring buffer create failed\n");
  398. close(self->fd);
  399. self->fd = -1;
  400. return ALC_OUT_OF_MEMORY;
  401. }
  402. self->data_size = info.fragsize;
  403. self->read_data = calloc(1, self->data_size);
  404. self->killNow = 0;
  405. if(althrd_create(&self->thread, ALCcaptureOSS_recordProc, self) != althrd_success)
  406. {
  407. device->ExtraData = NULL;
  408. close(self->fd);
  409. self->fd = -1;
  410. return ALC_OUT_OF_MEMORY;
  411. }
  412. al_string_copy_cstr(&device->DeviceName, name);
  413. return ALC_NO_ERROR;
  414. }
  415. static void ALCcaptureOSS_close(ALCcaptureOSS *self)
  416. {
  417. int res;
  418. self->killNow = 1;
  419. althrd_join(self->thread, &res);
  420. close(self->fd);
  421. self->fd = -1;
  422. DestroyRingBuffer(self->ring);
  423. self->ring = NULL;
  424. free(self->read_data);
  425. self->read_data = NULL;
  426. }
  427. static ALCboolean ALCcaptureOSS_start(ALCcaptureOSS *self)
  428. {
  429. self->doCapture = 1;
  430. return ALC_TRUE;
  431. }
  432. static void ALCcaptureOSS_stop(ALCcaptureOSS *self)
  433. {
  434. self->doCapture = 0;
  435. }
  436. static ALCenum ALCcaptureOSS_captureSamples(ALCcaptureOSS *self, ALCvoid *buffer, ALCuint samples)
  437. {
  438. ReadRingBuffer(self->ring, buffer, samples);
  439. return ALC_NO_ERROR;
  440. }
  441. static ALCuint ALCcaptureOSS_availableSamples(ALCcaptureOSS *self)
  442. {
  443. return RingBufferSize(self->ring);
  444. }
  445. typedef struct ALCossBackendFactory {
  446. DERIVE_FROM_TYPE(ALCbackendFactory);
  447. } ALCossBackendFactory;
  448. #define ALCOSSBACKENDFACTORY_INITIALIZER { { GET_VTABLE2(ALCossBackendFactory, ALCbackendFactory) } }
  449. ALCbackendFactory *ALCossBackendFactory_getFactory(void);
  450. static ALCboolean ALCossBackendFactory_init(ALCossBackendFactory *self);
  451. static DECLARE_FORWARD(ALCossBackendFactory, ALCbackendFactory, void, deinit)
  452. static ALCboolean ALCossBackendFactory_querySupport(ALCossBackendFactory *self, ALCbackend_Type type);
  453. static void ALCossBackendFactory_probe(ALCossBackendFactory *self, enum DevProbe type);
  454. static ALCbackend* ALCossBackendFactory_createBackend(ALCossBackendFactory *self, ALCdevice *device, ALCbackend_Type type);
  455. DEFINE_ALCBACKENDFACTORY_VTABLE(ALCossBackendFactory);
  456. ALCbackendFactory *ALCossBackendFactory_getFactory(void)
  457. {
  458. static ALCossBackendFactory factory = ALCOSSBACKENDFACTORY_INITIALIZER;
  459. return STATIC_CAST(ALCbackendFactory, &factory);
  460. }
  461. ALCboolean ALCossBackendFactory_init(ALCossBackendFactory* UNUSED(self))
  462. {
  463. ConfigValueStr(NULL, "oss", "device", &oss_driver);
  464. ConfigValueStr(NULL, "oss", "capture", &oss_capture);
  465. return ALC_TRUE;
  466. }
  467. ALCboolean ALCossBackendFactory_querySupport(ALCossBackendFactory* UNUSED(self), ALCbackend_Type type)
  468. {
  469. if(type == ALCbackend_Playback || type == ALCbackend_Capture)
  470. return ALC_TRUE;
  471. return ALC_FALSE;
  472. }
  473. void ALCossBackendFactory_probe(ALCossBackendFactory* UNUSED(self), enum DevProbe type)
  474. {
  475. switch(type)
  476. {
  477. case ALL_DEVICE_PROBE:
  478. {
  479. #ifdef HAVE_STAT
  480. struct stat buf;
  481. if(stat(oss_driver, &buf) == 0)
  482. #endif
  483. AppendAllDevicesList(oss_device);
  484. }
  485. break;
  486. case CAPTURE_DEVICE_PROBE:
  487. {
  488. #ifdef HAVE_STAT
  489. struct stat buf;
  490. if(stat(oss_capture, &buf) == 0)
  491. #endif
  492. AppendCaptureDeviceList(oss_device);
  493. }
  494. break;
  495. }
  496. }
  497. ALCbackend* ALCossBackendFactory_createBackend(ALCossBackendFactory* UNUSED(self), ALCdevice *device, ALCbackend_Type type)
  498. {
  499. if(type == ALCbackend_Playback)
  500. {
  501. ALCplaybackOSS *backend;
  502. NEW_OBJ(backend, ALCplaybackOSS)(device);
  503. if(!backend) return NULL;
  504. return STATIC_CAST(ALCbackend, backend);
  505. }
  506. if(type == ALCbackend_Capture)
  507. {
  508. ALCcaptureOSS *backend;
  509. NEW_OBJ(backend, ALCcaptureOSS)(device);
  510. if(!backend) return NULL;
  511. return STATIC_CAST(ALCbackend, backend);
  512. }
  513. return NULL;
  514. }