ao_write.c

   1 /*
   2  * Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file ao_write.c Paraslash's libao output plugin. */
   8
   9 #include <pthread.h>
  10 #include <ao/ao.h>
  11 #include <regex.h>
  12 #include <lopsub.h>
  13
  14 #include "write_cmd.lsg.h"
  15 #include "para.h"
  16 #include "fd.h"
  17 #include "string.h"
  18 #include "list.h"
  19 #include "sched.h"
  20 #include "buffer_tree.h"
  21 #include "write.h"
  22 #include "error.h"
  23
  24 struct private_aow_data {
  25         ao_device *dev;
  26         int bytes_per_frame;
  27
  28         pthread_t thread;
  29         pthread_attr_t attr;
  30         /* The mutex and the condition variable serialize access to ->btrn */
  31         pthread_mutex_t mutex;
  32         pthread_cond_t data_available;
  33         struct btr_node *thread_btrn;
  34 };
  35
  36 static void aow_close(struct writer_node *wn)
  37 {
  38         struct private_aow_data *pawd = wn->private_data;
  39
  40         if (!pawd)
  41                 return;
  42         assert(!pawd->thread_btrn);
  43         ao_close(pawd->dev);
  44         free(pawd);
  45         wn->private_data = NULL;
  46         ao_shutdown();
  47 }
  48
  49 static void aow_pre_select(struct sched *s, void *context)
  50 {
  51         struct writer_node *wn = context;
  52         struct private_aow_data *pawd = wn->private_data;
  53         int ret;
  54
  55         if (!pawd) { /* not yet started */
  56                 assert(wn->btrn);
  57                 ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
  58                 if (ret != 0)
  59                         goto min_delay;
  60                 return; /* no data available */
  61         }
  62         if (!wn->btrn) { /* EOF */
  63                 if (!pawd->thread_btrn) /* ready to exit */
  64                         goto min_delay;
  65                 /* wait for the play thread to terminate */
  66                 goto timeout;
  67         }
  68         pthread_mutex_lock(&pawd->mutex);
  69         ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
  70         pthread_mutex_unlock(&pawd->mutex);
  71         if (ret != 0)
  72                 goto min_delay;
  73         /*
  74          * Even though the node status is zero, we might have data available,
  75          * but the output buffer is full. If we don't set a timeout here, we
  76          * are woken up only if new data arrives, which might be too late and
  77          * result in a buffer underrun in the playing thread. To avoid this we
  78          * never sleep longer than the (default) buffer time.
  79          */
  80 timeout:
  81         return sched_request_timeout_ms(20, s);
  82 min_delay:
  83         sched_min_delay(s);
  84 }
  85
  86 static int aow_set_sample_format(unsigned sample_rate, unsigned channels,
  87                 int sample_format, ao_sample_format *result)
  88 {
  89         memset(result, 0, sizeof(*result));
  90         switch (sample_format) {
  91                 case SF_U8:
  92                 case SF_U16_LE:
  93                 case SF_U16_BE:
  94                         return -E_AO_BAD_SAMPLE_FORMAT;
  95                 case SF_S8:
  96                         /* no need to set byte_format */
  97                         result->bits = 8;
  98                         break;
  99                 case SF_S16_LE:
 100                         result->bits = 16;
 101                         result->byte_format = AO_FMT_LITTLE;
 102                         break;
 103                 case SF_S16_BE:
 104                         result->bits = 16;
 105                         result->byte_format = AO_FMT_BIG;
 106                         break;
 107                 default:
 108                         PARA_EMERG_LOG("bug: invalid sample format\n");
 109                         exit(EXIT_FAILURE);
 110         }
 111         result->channels = channels;
 112         result->rate = sample_rate;
 113         return 1;
 114 }
 115
 116 static int aow_open_device(int id, ao_sample_format *asf, ao_option *options,
 117                 ao_device **result)
 118 {
 119         const char *msg;
 120         ao_device *dev = ao_open_live(id, asf, options);
 121
 122         if (dev) {
 123                 *result = dev;
 124                 return 1;
 125         }
 126         switch (errno) {
 127                 case AO_ENODRIVER:
 128                         msg = "No driver corresponds to driver_id";
 129                         break;
 130                 case AO_ENOTLIVE:
 131                         msg = "This driver is not a live output device";
 132                         break;
 133                 case AO_EBADOPTION:
 134                         msg = "A valid option key has an invalid value";
 135                         break;
 136                 case AO_EOPENDEVICE:
 137                         msg = "Cannot open the device";
 138                         break;
 139                 case AO_EFAIL:
 140                         msg = "General libao error";
 141                         break;
 142                 default:
 143                         msg = "Unknown ao error";
 144                         break;
 145         }
 146         PARA_ERROR_LOG("%s\n", msg);
 147         return -E_AO_OPEN_LIVE;
 148 }
 149
 150 static void aow_show_drivers(void)
 151 {
 152         int i, j, num_drivers;
 153         ao_info **driver_list;
 154
 155         PARA_DEBUG_LOG("libao drivers available on this host:\n");
 156         PARA_DEBUG_LOG("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
 157
 158         driver_list = ao_driver_info_list(&num_drivers);
 159
 160         for (i = 0; i < num_drivers; i++) {
 161                 ao_info *info = driver_list[i];
 162                 char *keys = NULL, *tmp = NULL;
 163
 164                 if (info->type == AO_TYPE_FILE)
 165                         continue;
 166                 PARA_DEBUG_LOG("%s: %s", info->short_name, info->name);
 167                 PARA_DEBUG_LOG("priority: %d", info->priority);
 168                 for (j = 0; j < info->option_count; j++) {
 169                         tmp = make_message("%s%s%s", keys? keys : "",
 170                                 keys? ", " : "",
 171                                 info->options[j]);
 172                         free(keys);
 173                         keys = tmp;
 174                 }
 175                 PARA_DEBUG_LOG("keys: %s", keys? keys : "[none]");
 176                 free(keys);
 177                 PARA_DEBUG_LOG("comment: %s", info->comment?
 178                         info->comment : "[none]");
 179         }
 180 }
 181
 182 static int aow_init(struct writer_node *wn, unsigned sample_rate,
 183                 unsigned channels, int sample_format)
 184 {
 185         int id, ret, i;
 186         ao_option *aoo = NULL;
 187         ao_sample_format asf;
 188         ao_info *info;
 189         const struct lls_opt_result *r;
 190         unsigned n;
 191         struct private_aow_data *pawd = para_malloc(sizeof(*pawd));
 192
 193         ao_initialize();
 194         aow_show_drivers();
 195         if (WRITE_CMD_OPT_GIVEN(AO, DRIVER, wn->lpr)) {
 196                 ret = -E_AO_BAD_DRIVER;
 197                 id = ao_driver_id(WRITE_CMD_OPT_STRING_VAL(AO, DRIVER, wn->lpr));
 198         } else {
 199                 ret = -E_AO_DEFAULT_DRIVER;
 200                 id = ao_default_driver_id();
 201         }
 202         if (id < 0)
 203                 goto fail;
 204         info = ao_driver_info(id);
 205         assert(info && info->short_name);
 206         if (info->type == AO_TYPE_FILE) {
 207                 ret = -E_AO_FILE_NOT_SUPP;
 208                 goto fail;
 209         }
 210         PARA_INFO_LOG("using %s driver\n", info->short_name);
 211         r = WRITE_CMD_OPT_RESULT(AO, AO_OPTION, wn->lpr);
 212         n = lls_opt_given(r);
 213         for (i = 0; i < n; i++) {
 214                 char *o = para_strdup(lls_string_val(i, r));
 215                 char *value;
 216
 217                 ret = -E_AO_BAD_OPTION;
 218                 value = strchr(o, ':');
 219                 if (!value) {
 220                         free(o);
 221                         goto fail;
 222                 }
 223                 *value = '\0';
 224                 value++;
 225                 PARA_INFO_LOG("appending option: key=%s, value=%s\n", o, value);
 226                 ret = ao_append_option(&aoo, o, value);
 227                 free(o);
 228                 if (ret == 0) {
 229                         ret = -E_AO_APPEND_OPTION;
 230                         goto fail;
 231                 }
 232         }
 233         ret = aow_set_sample_format(sample_rate, channels, sample_format, &asf);
 234         if (ret < 0)
 235                 goto fail;
 236         if (sample_format == SF_S8 || sample_format == SF_U8)
 237                 pawd->bytes_per_frame = channels;
 238         else
 239                 pawd->bytes_per_frame = channels * 2;
 240         ret = aow_open_device(id, &asf, aoo, &pawd->dev);
 241         if (ret < 0)
 242                 goto fail;
 243         PARA_INFO_LOG("successfully opened %s\n", info->short_name);
 244         wn->private_data = pawd;
 245         return 1;
 246 fail:
 247         free(pawd);
 248         return ret;
 249 }
 250
 251 __noreturn static void *aow_play(void *priv)
 252 {
 253         struct writer_node *wn = priv;
 254         struct private_aow_data *pawd = wn->private_data;
 255         struct btr_node *btrn = pawd->thread_btrn;
 256         size_t frames, bytes;
 257         char *data;
 258         int ret;
 259
 260         pthread_mutex_lock(&pawd->mutex);
 261         for (;;) {
 262                 for (;;) {
 263                         ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
 264                         if (ret < 0)
 265                                 goto fail;
 266                         if (ret > 0) {
 267                                 btr_merge(btrn, wn->min_iqs);
 268                                 bytes = btr_next_buffer(btrn, &data);
 269                                 frames = bytes / pawd->bytes_per_frame;
 270                                 if (frames > 0)
 271                                         break;
 272                                 /* eof and less than a single frame available */
 273                                 ret = -E_WRITE_COMMON_EOF;
 274                                 goto fail;
 275                         }
 276                         /*
 277                          * No data available, go to sleep and wait for the main
 278                          * thread to wake us up. pthread_cond_wait() unlocks
 279                          * the mutex while it waits and locks it again upon
 280                          * return.
 281                          */
 282                         ret = pthread_cond_wait(&pawd->data_available,
 283                                 &pawd->mutex);
 284                         /* pthread_cond_wait() can never fail here */
 285                         assert(ret == 0);
 286                 }
 287                 assert(frames > 0);
 288                 bytes = frames * pawd->bytes_per_frame;
 289                 pthread_mutex_unlock(&pawd->mutex);
 290                 ret = ao_play(pawd->dev, data, bytes);
 291                 pthread_mutex_lock(&pawd->mutex);
 292                 if (ret == 0) { /* failure */
 293                         ret = -E_AO_PLAY;
 294                         goto fail;
 295                 }
 296                 btr_consume(btrn, bytes);
 297         }
 298 fail:
 299         btr_remove_node(&pawd->thread_btrn);
 300         assert(ret < 0);
 301         PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
 302         pthread_mutex_unlock(&pawd->mutex);
 303         pthread_exit(NULL);
 304 }
 305
 306 static int aow_create_thread(struct writer_node *wn)
 307 {
 308         struct private_aow_data *pawd = wn->private_data;
 309         int ret;
 310         const char *msg;
 311
 312         /* initialize with default attributes */
 313         msg = "could not init mutex";
 314         ret = pthread_mutex_init(&pawd->mutex, NULL);
 315         if (ret < 0)
 316                 goto fail;
 317
 318         msg = "could not initialize condition variable";
 319         ret = pthread_cond_init(&pawd->data_available, NULL);
 320         if (ret < 0)
 321                 goto fail;
 322
 323         msg = "could not initialize thread attributes";
 324         ret = pthread_attr_init(&pawd->attr);
 325         if (ret < 0)
 326                 goto fail;
 327
 328         /* schedule this thread under the real-time policy SCHED_FIFO */
 329         msg = "could not set sched policy";
 330         ret = pthread_attr_setschedpolicy(&pawd->attr, SCHED_FIFO);
 331         if (ret < 0)
 332                 goto fail;
 333
 334         msg = "could not set detach state to joinable";
 335         ret = pthread_attr_setdetachstate(&pawd->attr, PTHREAD_CREATE_JOINABLE);
 336         if (ret < 0)
 337                 goto fail;
 338
 339         msg = "could not create thread";
 340         ret = pthread_create(&pawd->thread, &pawd->attr, aow_play, wn);
 341         if (ret < 0)
 342                 goto fail;
 343         return 1;
 344 fail:
 345         PARA_ERROR_LOG("%s (%s)\n", msg, strerror(ret));
 346         return -E_AO_PTHREAD;
 347 }
 348
 349 static int aow_post_select(__a_unused struct sched *s, void *context)
 350 {
 351         struct writer_node *wn = context;
 352         struct private_aow_data *pawd = wn->private_data;
 353         int ret;
 354
 355         if (!pawd) {
 356                 int32_t rate, ch, format;
 357                 struct btr_node_description bnd;
 358
 359                 ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 360                 if (ret < 0)
 361                         goto remove_btrn;
 362                 if (ret == 0)
 363                         return 0;
 364                 get_btr_sample_rate(wn->btrn, &rate);
 365                 get_btr_channels(wn->btrn, &ch);
 366                 get_btr_sample_format(wn->btrn, &format);
 367                 ret = aow_init(wn, rate, ch, format);
 368                 if (ret < 0)
 369                         goto remove_btrn;
 370                 pawd = wn->private_data;
 371
 372                 /* set up thread btr node */
 373                 bnd.name = "ao_thread_btrn";
 374                 bnd.parent = wn->btrn;
 375                 bnd.child = NULL;
 376                 bnd.handler = NULL;
 377                 bnd.context = pawd;
 378                 pawd->thread_btrn = btr_new_node(&bnd);
 379                 wn->private_data = pawd;
 380
 381                 ret = aow_create_thread(wn);
 382                 if (ret < 0)
 383                         goto remove_thread_btrn;
 384                 return 0;
 385         }
 386         if (!wn->btrn) {
 387                 if (!pawd->thread_btrn) {
 388                         pthread_join(pawd->thread, NULL);
 389                         return -E_AO_EOF;
 390                 }
 391                 PARA_INFO_LOG("waiting for play thread to terminate\n");
 392                 return 0;
 393         }
 394         pthread_mutex_lock(&pawd->mutex);
 395         ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 396         if (ret > 0) {
 397                 btr_pushdown(wn->btrn);
 398                 if (pthread_cond_signal(&pawd->data_available) != 0) {
 399                         ret = -E_AO_PTHREAD;
 400                         PARA_ERROR_LOG("pthread_cond_signal() failed\n");
 401                         goto remove_thread_btrn;
 402                 }
 403         }
 404         if (ret >= 0) {
 405                 pthread_mutex_unlock(&pawd->mutex);
 406                 goto out;
 407         }
 408         btr_remove_node(&wn->btrn);
 409         pthread_cond_signal(&pawd->data_available);
 410         pthread_mutex_unlock(&pawd->mutex);
 411         return 0;
 412 remove_thread_btrn:
 413         btr_remove_node(&pawd->thread_btrn);
 414 remove_btrn:
 415         btr_remove_node(&wn->btrn);
 416 out:
 417         return ret;
 418 }
 419
 420 struct writer lsg_write_cmd_com_ao_user_data = {
 421         .close = aow_close,
 422         .pre_select = aow_pre_select,
 423         .post_select = aow_post_select,
 424 };
 425