play.c

   1 /*
   2  * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
   3  *
   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.
   8  *
   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.
  13  *
  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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  17  */
  18
  19 /*
  20  * Based in parts on aplay.c from the alsa-utils-1.0.8 package,
  21  * Copyright (c) by Jaroslav Kysela <perex@suse.cz>, which is
  22  * based on the vplay program by Michael Beck.
  23  */
  24
  25 #define BUFFER_SIZE 1000 * 1000
  26 #define WAV_HEADER_LEN 44
  27 #include <sys/time.h> /* gettimeofday */
  28 #include "para.h"
  29 #include "play.cmdline.h"
  30 #include <alsa/asoundlib.h>
  31
  32 enum {  E_BROKEN_CONF,          /* Broken configuration for this PCM */
  33         E_ACCESS_TYPE,          /* Access type not available */
  34         E_SAMPLE_FORMAT,        /* Sample format not available */
  35         E_CHANNEL_COUNT,        /* Channels count not available */
  36         E_HW_PARAMS,            /* Unable to install hw params */
  37         E_SW_PARAMS,            /* Unable to install sw params */
  38         E_BAD_PERIOD,           /* Can't use period equal to buffer size */
  39         E_GET_XFER,             /* Unable to obtain xfer align */
  40         E_SET_XFER,             /* snd_pcm_sw_params_set_xfer_align failed */
  41         E_MEM,                  /* not enough memory */
  42         E_READ,                 /* read error */
  43         E_WRITE,                /* write error */
  44         E_PIPE,                 /* write to pipe with other side closed */
  45         E_PCM_OPEN,             /* unable to open pcm */
  46         E_SND_PCM_INFO,         /* pcm info error */
  47         E_GET_BUFFER_TIME,      /* snd_pcm_hw_params_get_buffer_time_max failed */
  48         E_SET_BUFFER_TIME,      /* snd_pcm_hw_params_set_buffer_time_near failed */
  49         E_SET_RATE,             /* snd_pcm_hw_params_set_rate_near failed */
  50         E_START_THRESHOLD,      /* snd_pcm_sw_params_set_start_threshold failed */
  51         E_STOP_THRESHOLD,       /* snd_pcm_sw_params_set_stop_threshold failed */
  52         E_LOG,                  /* snd_output_stdio_attach failed */
  53         E_SYNTAX                /* could not parse start_time option */
  54 };
  55
  56 #define FORMAT SND_PCM_FORMAT_S16_LE
  57
  58 #define EXIT(EXP) \
  59 do { if (EXP) \
  60         fprintf (stderr, "error: " #EXP "\n"); exit(EXP);} \
  61 while (0)
  62
  63 static snd_pcm_t *handle;
  64 static unsigned char *audiobuf;
  65 static snd_pcm_uframes_t chunk_size;
  66 static size_t bytes_per_frame;
  67 static struct timeval *start_time;
  68 static struct gengetopt_args_info conf;
  69
  70 /*
  71  * read_wav_header - read WAV_HEADER_LEN bytes from stdin to audio buffer
  72  *
  73  * Exit on errors and on eof before WAV_HEADER_LEN could be read.
  74  */
  75 static void read_wav_header(void)
  76 {
  77         ssize_t ret, count = 0;
  78
  79         while (count < WAV_HEADER_LEN) {
  80                 ret = read(STDIN_FILENO, audiobuf + count, WAV_HEADER_LEN - count);
  81                 if (ret <= 0)
  82                         EXIT(E_READ);
  83                 count += ret;
  84         }
  85 }
  86
  87 /*
  88  * set_alsa_params - Prepare the PCM handle for writing
  89  *
  90  * Install PCM software and hardware configuration. Exit on errors.
  91  */
  92 static void set_alsa_params(void)
  93 {
  94         snd_pcm_hw_params_t *hwparams;
  95         snd_pcm_sw_params_t *swparams;
  96         snd_pcm_uframes_t buffer_size, xfer_align, start_threshold,
  97                 stop_threshold;
  98         unsigned buffer_time = 0;
  99         int err;
 100
 101         snd_pcm_hw_params_alloca(&hwparams);
 102         snd_pcm_sw_params_alloca(&swparams);
 103         if (snd_pcm_hw_params_any(handle, hwparams) < 0)
 104                 EXIT(E_BROKEN_CONF);
 105         if (snd_pcm_hw_params_set_access(handle, hwparams,
 106                         SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
 107                 EXIT(E_ACCESS_TYPE);
 108         if (snd_pcm_hw_params_set_format(handle, hwparams, FORMAT) < 0)
 109                 EXIT(E_SAMPLE_FORMAT);
 110         if (snd_pcm_hw_params_set_channels(handle, hwparams, conf.channels_arg) < 0)
 111                 EXIT(E_CHANNEL_COUNT);
 112         if (snd_pcm_hw_params_set_rate_near(handle, hwparams, (unsigned int*) &conf.sample_rate_arg, 0) < 0)
 113                 EXIT(E_SET_RATE);
 114         err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, 0);
 115         if (err < 0 || !buffer_time)
 116                 EXIT(E_GET_BUFFER_TIME);
 117         if (buffer_time > 500000)
 118                 buffer_time = 500000;
 119         if (snd_pcm_hw_params_set_buffer_time_near(handle, hwparams,
 120                         &buffer_time, 0) < 0)
 121                 EXIT(E_SET_BUFFER_TIME);
 122         if (snd_pcm_hw_params(handle, hwparams) < 0)
 123                 EXIT(E_HW_PARAMS);
 124         snd_pcm_hw_params_get_period_size(hwparams, &chunk_size, 0);
 125         snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
 126         if (chunk_size == buffer_size)
 127                 EXIT(E_BAD_PERIOD);
 128         snd_pcm_sw_params_current(handle, swparams);
 129         err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
 130         if (err < 0 || !xfer_align)
 131                 EXIT(E_GET_XFER);
 132         snd_pcm_sw_params_set_sleep_min(handle, swparams, 0);
 133         snd_pcm_sw_params_set_avail_min(handle, swparams, chunk_size);
 134         /* round to closest transfer boundary */
 135         start_threshold = (buffer_size / xfer_align) * xfer_align;
 136         if (start_threshold < 1)
 137                 start_threshold = 1;
 138         if (snd_pcm_sw_params_set_start_threshold(handle, swparams,
 139                         start_threshold) < 0)
 140                 EXIT(E_START_THRESHOLD);
 141         stop_threshold = buffer_size;
 142         if (snd_pcm_sw_params_set_stop_threshold(handle, swparams,
 143                         stop_threshold) < 0)
 144                 EXIT(E_STOP_THRESHOLD);
 145         if (snd_pcm_sw_params_set_xfer_align(handle, swparams, xfer_align) < 0)
 146                 EXIT(E_SET_XFER);
 147         if (snd_pcm_sw_params(handle, swparams) < 0)
 148                 EXIT(E_SW_PARAMS);
 149         bytes_per_frame = snd_pcm_format_physical_width(FORMAT) * conf.channels_arg / 8;
 150 }
 151
 152 /*
 153  * pcm_write - push out pcm frames
 154  * @data: pointer do data to be written
 155  * @count: number of frames
 156  *
 157  * Return value: Number of bytes written. Exit on errors.
 158  */
 159 static snd_pcm_sframes_t pcm_write(u_char *data, size_t count)
 160 {
 161         snd_pcm_sframes_t r, result = 0;
 162 #if 0
 163         if (count < chunk_size) {
 164                 snd_pcm_format_set_silence(FORMAT, data
 165                         + count * bytes_per_frame,
 166                         (chunk_size - count) * conf.channels_arg);
 167                 count = chunk_size;
 168         }
 169 #endif
 170         while (count > 0) {
 171                 /* write interleaved frames */
 172                 r = snd_pcm_writei(handle, data, count);
 173                 if (r == -EAGAIN || (r >= 0 && r < count))
 174                         snd_pcm_wait(handle, 1);
 175                 else if (r == -EPIPE)
 176                         snd_pcm_prepare(handle);
 177                 else if (r < 0)
 178                         EXIT(E_WRITE);
 179                 if (r > 0) {
 180                         result += r;
 181                         count -= r;
 182                         data += r * bytes_per_frame;
 183                 }
 184         }
 185         return result;
 186 }
 187
 188 /*
 189  * start_time_in_future - check if current time is later than start_time
 190  * @diff: pointer to write remaining time to
 191  *
 192  * If start_time was not given, or current time is later than given
 193  * start_time, return 0. Otherwise, return 1 and write the time
 194  * difference between current time and start_time to diff. diff may be
 195  * NULL.
 196  *
 197  */
 198 static int start_time_in_future(struct timeval *diff)
 199 {
 200         struct timeval now;
 201
 202         if (!conf.start_time_given)
 203                 return 0;
 204         gettimeofday(&now, NULL);
 205         return tv_diff(start_time, &now, diff) > 0? 1 : 0;
 206 }
 207
 208 /*
 209  * do_initial_delay - sleep until time given at command line
 210  *
 211  * This is called if the initial buffer is filled. It returns
 212  * immediately if no start_time was given at the command line
 213  * or if the given start time is in the past.
 214  *
 215  */
 216 static void do_initial_delay(void)
 217 {
 218         struct timeval diff;
 219         int ret;
 220
 221         fprintf(stderr, "initial delay\n");
 222         if (!conf.start_time_given)
 223                 return;
 224 again:
 225         if (!start_time_in_future(&diff))
 226                 return;
 227         ret = select(1, NULL, NULL, NULL, &diff);
 228         if (ret < 0 && errno == EINTR)
 229                 goto again;
 230 }
 231
 232
 233 /*
 234  * play_pcm - play raw pcm data
 235  * @l: number of bytes already loaded
 236  *
 237  * If start_time was given, prebuffer data until buffer is full or
 238  * start_time is reached. In any case, do not start playing before
 239  * start_time.
 240  */
 241 static void play_pcm(size_t l)
 242 {
 243         ssize_t r, w;
 244         unsigned long written = 0;
 245         size_t chunk_bytes;
 246
 247         set_alsa_params();
 248         chunk_bytes = chunk_size * bytes_per_frame;
 249         audiobuf = realloc(audiobuf, BUFFER_SIZE);
 250 //      fprintf(stderr, "loaded: %d, chunk_bytes: %d\n", l, chunk_bytes);
 251         if (!audiobuf)
 252                 EXIT(E_MEM);
 253         for (;;) {
 254                 for (;;) {
 255                         if (l >= chunk_bytes) {
 256                                 if (written)
 257                                         break;
 258                                 if (!start_time)
 259                                         break;
 260                                 if (!start_time_in_future(NULL))
 261                                         break;
 262                                 if (l > BUFFER_SIZE) {
 263                                         do_initial_delay();
 264                                         break;
 265                                 }
 266                         }
 267 //                      fprintf(stderr, "l = %d, chunk_Bytes = %d\n", l, chunk_bytes);
 268                         r = read(STDIN_FILENO, audiobuf + l, BUFFER_SIZE -l);
 269                         if (r < 0)
 270                                 EXIT(E_READ);
 271                         l += r;
 272 //                      fprintf(stderr, "loaded: %d, r= %d\n", l, r);
 273                         if (!r)
 274                                 goto out;;
 275                 }
 276                 w = MIN(chunk_bytes, l);
 277 //              fprintf(stderr, "play: writing %d\n", w);
 278                 r = (ssize_t) pcm_write(audiobuf, w / bytes_per_frame) * bytes_per_frame;
 279 //              fprintf(stderr, "wrote %d\n", r);
 280                 if (r < 0)
 281                         EXIT(E_WRITE);
 282                 written += r;
 283                 l -= r;
 284                 if (l)
 285                         memmove(audiobuf, audiobuf + r, l);
 286 //              fprintf(stderr, "written %lu, loaded : %d\n", written, l);
 287         }
 288 out:
 289         snd_pcm_drain(handle);
 290 }
 291
 292 /*
 293  * check_wave - test if audio buffer contains a valid wave header
 294  *
 295  * If not, return 0, otherwise, store number of channels and sample rate
 296  * in struct conf and return WAV_HEADER_LEN.
 297  */
 298 static size_t check_wave(void)
 299 {
 300         unsigned char *a = audiobuf;
 301         if (a[0] != 'R' || a[1] != 'I' || a[2] != 'F' || a[3] != 'F')
 302                 return WAV_HEADER_LEN;
 303         conf.channels_arg = (unsigned) a[22];
 304         conf.sample_rate_arg = a[24] + (a[25] << 8) + (a[26] << 16) + (a[27] << 24);
 305 //      fprintf(stderr, "channels: %d, rate: %d\n", conf.channels_arg,
 306 //              conf.sample_rate_arg);
 307         return 0;
 308 }
 309
 310 int main(int argc, char *argv[])
 311 {
 312         snd_pcm_info_t *info;
 313         snd_output_t *log;
 314         struct timeval tv;
 315         int err;
 316
 317         cmdline_parser(argc, argv, &conf);
 318         if (conf.start_time_given) {
 319                 if (sscanf(conf.start_time_arg, "%lu:%lu",
 320                                 &tv.tv_sec, &tv.tv_usec) != 2)
 321                         EXIT(E_SYNTAX);
 322                 start_time = &tv;
 323         }
 324 //      fprintf(stderr, "argc=%d, argv[1]=%s\n",argc,  argv[1]);
 325         snd_pcm_info_alloca(&info);
 326         if (snd_output_stdio_attach(&log, stderr, 0) < 0)
 327                 EXIT(E_LOG);
 328         err = snd_pcm_open(&handle, "plug:swmix",
 329                 SND_PCM_STREAM_PLAYBACK, 0);
 330         if (err < 0)
 331                 EXIT(E_PCM_OPEN);
 332         if ((err = snd_pcm_info(handle, info)) < 0)
 333                 EXIT(E_SND_PCM_INFO);
 334         audiobuf = malloc(WAV_HEADER_LEN);
 335         read_wav_header();
 336         play_pcm(check_wave());
 337         snd_pcm_close(handle);
 338         free(audiobuf);
 339         snd_output_close(log);
 340         snd_config_update_free_global();
 341         return EXIT_SUCCESS;
 342 }