ao_write.c

   1 /* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
   2
   3 /** \file ao_write.c Paraslash's libao output plugin. */
   4
   5 #include <pthread.h>
   6 #include <ao/ao.h>
   7 #include <regex.h>
   8 #include <lopsub.h>
   9
  10 #include "write_cmd.lsg.h"
  11 #include "para.h"
  12 #include "fd.h"
  13 #include "string.h"
  14 #include "list.h"
  15 #include "sched.h"
  16 #include "buffer_tree.h"
  17 #include "write.h"
  18 #include "error.h"
  19
  20 struct private_aow_data {
  21         ao_device *dev;
  22         int bytes_per_frame;
  23
  24         pthread_t thread;
  25         pthread_attr_t attr;
  26         /* The mutex and the condition variable serialize access to ->btrn */
  27         pthread_mutex_t mutex;
  28         pthread_cond_t data_available;
  29         struct btr_node *thread_btrn;
  30 };
  31
  32 static void aow_close(struct writer_node *wn)
  33 {
  34         struct private_aow_data *pawd = wn->private_data;
  35
  36         if (!pawd)
  37                 return;
  38         assert(!pawd->thread_btrn);
  39         ao_close(pawd->dev);
  40         free(pawd);
  41         wn->private_data = NULL;
  42         ao_shutdown();
  43 }
  44
  45 static void aow_pre_select(struct sched *s, void *context)
  46 {
  47         struct writer_node *wn = context;
  48         struct private_aow_data *pawd = wn->private_data;
  49         int ret;
  50
  51         if (!pawd) { /* not yet started */
  52                 assert(wn->btrn);
  53                 ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
  54                 if (ret != 0)
  55                         goto min_delay;
  56                 return; /* no data available */
  57         }
  58         if (!wn->btrn) { /* EOF */
  59                 if (!pawd->thread_btrn) /* ready to exit */
  60                         goto min_delay;
  61                 /* wait for the play thread to terminate */
  62                 goto timeout;
  63         }
  64         pthread_mutex_lock(&pawd->mutex);
  65         ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
  66         pthread_mutex_unlock(&pawd->mutex);
  67         if (ret != 0)
  68                 goto min_delay;
  69         /*
  70          * Even though the node status is zero, we might have data available,
  71          * but the output buffer is full. If we don't set a timeout here, we
  72          * are woken up only if new data arrives, which might be too late and
  73          * result in a buffer underrun in the playing thread. To avoid this we
  74          * never sleep longer than the (default) buffer time.
  75          */
  76 timeout:
  77         return sched_request_timeout_ms(20, s);
  78 min_delay:
  79         sched_min_delay(s);
  80 }
  81
  82 static int aow_set_sample_format(unsigned sample_rate, unsigned channels,
  83                 int sample_format, ao_sample_format *result)
  84 {
  85         memset(result, 0, sizeof(*result));
  86         switch (sample_format) {
  87                 case SF_U8:
  88                 case SF_U16_LE:
  89                 case SF_U16_BE:
  90                         return -E_BAD_SAMPLE_FORMAT;
  91                 case SF_S8:
  92                         /* no need to set byte_format */
  93                         result->bits = 8;
  94                         break;
  95                 case SF_S16_LE:
  96                         result->bits = 16;
  97                         result->byte_format = AO_FMT_LITTLE;
  98                         break;
  99                 case SF_S16_BE:
 100                         result->bits = 16;
 101                         result->byte_format = AO_FMT_BIG;
 102                         break;
 103                 default:
 104                         PARA_EMERG_LOG("bug: invalid sample format\n");
 105                         exit(EXIT_FAILURE);
 106         }
 107         result->channels = channels;
 108         result->rate = sample_rate;
 109         return 1;
 110 }
 111
 112 static int aow_open_device(int id, ao_sample_format *asf, ao_option *options,
 113                 ao_device **result)
 114 {
 115         const char *msg;
 116         ao_device *dev = ao_open_live(id, asf, options);
 117
 118         if (dev) {
 119                 *result = dev;
 120                 return 1;
 121         }
 122         switch (errno) {
 123                 case AO_ENODRIVER:
 124                         msg = "No driver corresponds to driver_id";
 125                         break;
 126                 case AO_ENOTLIVE:
 127                         msg = "This driver is not a live output device";
 128                         break;
 129                 case AO_EBADOPTION:
 130                         msg = "A valid option key has an invalid value";
 131                         break;
 132                 case AO_EOPENDEVICE:
 133                         msg = "Cannot open the device";
 134                         break;
 135                 case AO_EFAIL:
 136                         msg = "General libao error";
 137                         break;
 138                 default:
 139                         msg = "Unknown ao error";
 140                         break;
 141         }
 142         PARA_ERROR_LOG("%s\n", msg);
 143         return -E_AO_OPEN_LIVE;
 144 }
 145
 146 static void aow_show_drivers(void)
 147 {
 148         int i, j, num_drivers;
 149         ao_info **driver_list;
 150
 151         PARA_DEBUG_LOG("libao drivers available on this host:\n");
 152         PARA_DEBUG_LOG("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
 153
 154         driver_list = ao_driver_info_list(&num_drivers);
 155
 156         for (i = 0; i < num_drivers; i++) {
 157                 ao_info *info = driver_list[i];
 158                 char *keys = NULL, *tmp = NULL;
 159
 160                 if (info->type == AO_TYPE_FILE)
 161                         continue;
 162                 PARA_DEBUG_LOG("name: %s: %s\n", info->short_name, info->name);
 163                 PARA_DEBUG_LOG("priority: %d\n", info->priority);
 164                 for (j = 0; j < info->option_count; j++) {
 165                         tmp = make_message("%s%s%s", keys? keys : "",
 166                                 keys? ", " : "",
 167                                 info->options[j]);
 168                         free(keys);
 169                         keys = tmp;
 170                 }
 171                 PARA_DEBUG_LOG("keys: %s\n", keys? keys : "[none]");
 172                 free(keys);
 173                 PARA_DEBUG_LOG("comment: %s\n", info->comment?
 174                         info->comment : "[none]");
 175         }
 176 }
 177
 178 static int aow_init(struct writer_node *wn, unsigned sample_rate,
 179                 unsigned channels, int sample_format)
 180 {
 181         int id, ret, i;
 182         ao_option *aoo = NULL;
 183         ao_sample_format asf;
 184         ao_info *info;
 185         const struct lls_opt_result *r;
 186         unsigned n;
 187         struct private_aow_data *pawd = para_malloc(sizeof(*pawd));
 188
 189         ao_initialize();
 190         aow_show_drivers();
 191         if (WRITE_CMD_OPT_GIVEN(AO, DRIVER, wn->lpr)) {
 192                 ret = -E_AO_BAD_DRIVER;
 193                 id = ao_driver_id(WRITE_CMD_OPT_STRING_VAL(AO, DRIVER, wn->lpr));
 194         } else {
 195                 ret = -E_AO_DEFAULT_DRIVER;
 196                 id = ao_default_driver_id();
 197         }
 198         if (id < 0)
 199                 goto fail;
 200         info = ao_driver_info(id);
 201         assert(info && info->short_name);
 202         if (info->type == AO_TYPE_FILE) {
 203                 ret = -E_AO_FILE_NOT_SUPP;
 204                 goto fail;
 205         }
 206         PARA_INFO_LOG("using %s driver\n", info->short_name);
 207         r = WRITE_CMD_OPT_RESULT(AO, AO_OPTION, wn->lpr);
 208         n = lls_opt_given(r);
 209         for (i = 0; i < n; i++) {
 210                 char *o = para_strdup(lls_string_val(i, r));
 211                 char *value;
 212
 213                 ret = -E_AO_BAD_OPTION;
 214                 value = strchr(o, ':');
 215                 if (!value) {
 216                         free(o);
 217                         goto fail;
 218                 }
 219                 *value = '\0';
 220                 value++;
 221                 PARA_INFO_LOG("appending option: key=%s, value=%s\n", o, value);
 222                 ret = ao_append_option(&aoo, o, value);
 223                 free(o);
 224                 if (ret == 0) {
 225                         ret = -E_AO_APPEND_OPTION;
 226                         goto fail;
 227                 }
 228         }
 229         ret = aow_set_sample_format(sample_rate, channels, sample_format, &asf);
 230         if (ret < 0)
 231                 goto fail;
 232         if (sample_format == SF_S8 || sample_format == SF_U8)
 233                 pawd->bytes_per_frame = channels;
 234         else
 235                 pawd->bytes_per_frame = channels * 2;
 236         ret = aow_open_device(id, &asf, aoo, &pawd->dev);
 237         if (ret < 0)
 238                 goto fail;
 239         PARA_INFO_LOG("successfully opened %s\n", info->short_name);
 240         wn->private_data = pawd;
 241         return 1;
 242 fail:
 243         free(pawd);
 244         return ret;
 245 }
 246
 247 static void *aow_play(void *priv)
 248 {
 249         struct writer_node *wn = priv;
 250         struct private_aow_data *pawd = wn->private_data;
 251         struct btr_node *btrn = pawd->thread_btrn;
 252         size_t frames, bytes;
 253         char *data;
 254         int ret;
 255
 256         pthread_mutex_lock(&pawd->mutex);
 257         for (;;) {
 258                 for (;;) {
 259                         ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
 260                         if (ret < 0)
 261                                 goto fail;
 262                         if (ret > 0) {
 263                                 btr_merge(btrn, wn->min_iqs);
 264                                 bytes = btr_next_buffer(btrn, &data);
 265                                 frames = bytes / pawd->bytes_per_frame;
 266                                 if (frames > 0)
 267                                         break;
 268                                 /* eof and less than a single frame available */
 269                                 ret = -E_WRITE_COMMON_EOF;
 270                                 goto fail;
 271                         }
 272                         /*
 273                          * No data available, go to sleep and wait for the main
 274                          * thread to wake us up. pthread_cond_wait() unlocks
 275                          * the mutex while it waits and locks it again upon
 276                          * return.
 277                          */
 278                         ret = pthread_cond_wait(&pawd->data_available,
 279                                 &pawd->mutex);
 280                         /* pthread_cond_wait() can never fail here */
 281                         assert(ret == 0);
 282                 }
 283                 assert(frames > 0);
 284                 bytes = frames * pawd->bytes_per_frame;
 285                 pthread_mutex_unlock(&pawd->mutex);
 286                 ret = ao_play(pawd->dev, data, bytes);
 287                 pthread_mutex_lock(&pawd->mutex);
 288                 if (ret == 0) { /* failure */
 289                         ret = -E_AO_PLAY;
 290                         goto fail;
 291                 }
 292                 btr_consume(btrn, bytes);
 293         }
 294 fail:
 295         btr_remove_node(&pawd->thread_btrn);
 296         assert(ret < 0);
 297         PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
 298         pthread_mutex_unlock(&pawd->mutex);
 299         pthread_exit(NULL);
 300 }
 301
 302 static int aow_create_thread(struct writer_node *wn)
 303 {
 304         struct private_aow_data *pawd = wn->private_data;
 305         int ret;
 306         const char *msg;
 307
 308         /* initialize with default attributes */
 309         msg = "could not init mutex";
 310         ret = pthread_mutex_init(&pawd->mutex, NULL);
 311         if (ret < 0)
 312                 goto fail;
 313
 314         msg = "could not initialize condition variable";
 315         ret = pthread_cond_init(&pawd->data_available, NULL);
 316         if (ret < 0)
 317                 goto fail;
 318
 319         msg = "could not initialize thread attributes";
 320         ret = pthread_attr_init(&pawd->attr);
 321         if (ret < 0)
 322                 goto fail;
 323
 324         /* schedule this thread under the real-time policy SCHED_FIFO */
 325         msg = "could not set sched policy";
 326         ret = pthread_attr_setschedpolicy(&pawd->attr, SCHED_FIFO);
 327         if (ret < 0)
 328                 goto fail;
 329
 330         msg = "could not set detach state to joinable";
 331         ret = pthread_attr_setdetachstate(&pawd->attr, PTHREAD_CREATE_JOINABLE);
 332         if (ret < 0)
 333                 goto fail;
 334
 335         msg = "could not create thread";
 336         ret = pthread_create(&pawd->thread, &pawd->attr, aow_play, wn);
 337         if (ret < 0)
 338                 goto fail;
 339         return 1;
 340 fail:
 341         PARA_ERROR_LOG("%s (%s)\n", msg, strerror(ret));
 342         return -E_AO_PTHREAD;
 343 }
 344
 345 static int aow_post_select(__a_unused struct sched *s, void *context)
 346 {
 347         struct writer_node *wn = context;
 348         struct private_aow_data *pawd = wn->private_data;
 349         int ret;
 350
 351         if (!pawd) {
 352                 int32_t rate, ch, format;
 353                 struct btr_node_description bnd;
 354
 355                 ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 356                 if (ret < 0)
 357                         goto remove_btrn;
 358                 if (ret == 0)
 359                         return 0;
 360                 get_btr_sample_rate(wn->btrn, &rate);
 361                 get_btr_channels(wn->btrn, &ch);
 362                 get_btr_sample_format(wn->btrn, &format);
 363                 ret = aow_init(wn, rate, ch, format);
 364                 if (ret < 0)
 365                         goto remove_btrn;
 366                 pawd = wn->private_data;
 367
 368                 /* set up thread btr node */
 369                 bnd.name = "ao_thread_btrn";
 370                 bnd.parent = wn->btrn;
 371                 bnd.child = NULL;
 372                 bnd.handler = NULL;
 373                 bnd.context = pawd;
 374                 pawd->thread_btrn = btr_new_node(&bnd);
 375                 wn->private_data = pawd;
 376
 377                 ret = aow_create_thread(wn);
 378                 if (ret < 0)
 379                         goto remove_thread_btrn;
 380                 return 0;
 381         }
 382         if (!wn->btrn) {
 383                 if (!pawd->thread_btrn) {
 384                         pthread_join(pawd->thread, NULL);
 385                         return -E_AO_EOF;
 386                 }
 387                 PARA_INFO_LOG("waiting for play thread to terminate\n");
 388                 return 0;
 389         }
 390         pthread_mutex_lock(&pawd->mutex);
 391         ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 392         if (ret > 0) {
 393                 btr_pushdown(wn->btrn);
 394                 if (pthread_cond_signal(&pawd->data_available) != 0) {
 395                         ret = -E_AO_PTHREAD;
 396                         PARA_ERROR_LOG("pthread_cond_signal() failed\n");
 397                         goto remove_thread_btrn;
 398                 }
 399         }
 400         if (ret >= 0) {
 401                 pthread_mutex_unlock(&pawd->mutex);
 402                 goto out;
 403         }
 404         btr_remove_node(&wn->btrn);
 405         pthread_cond_signal(&pawd->data_available);
 406         pthread_mutex_unlock(&pawd->mutex);
 407         return 0;
 408 remove_thread_btrn:
 409         btr_remove_node(&pawd->thread_btrn);
 410 remove_btrn:
 411         btr_remove_node(&wn->btrn);
 412 out:
 413         return ret;
 414 }
 415
 416 struct writer lsg_write_cmd_com_ao_user_data = {
 417         .close = aow_close,
 418         .pre_select = aow_pre_select,
 419         .post_select = aow_post_select,
 420 };
 421