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 WAV_HEADER_LEN 44
  26 #include <sys/time.h> /* gettimeofday */
  27 #include "para.h"
  28 #include "fd.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 void para_log(__a_unused int ll, const char* fmt,...)
  71 {
  72         va_list argp;
  73
  74         va_start(argp, fmt);
  75         vfprintf(stderr, fmt, argp);
  76         va_end(argp);
  77 }
  78
  79 /*
  80  * read_wav_header - read WAV_HEADER_LEN bytes from stdin to audio buffer
  81  *
  82  * Exit on errors and on eof before WAV_HEADER_LEN could be read.
  83  */
  84 static void read_wav_header(void)
  85 {
  86         ssize_t ret, count = 0;
  87
  88         while (count < WAV_HEADER_LEN) {
  89                 ret = read(STDIN_FILENO, audiobuf + count, WAV_HEADER_LEN - count);
  90                 if (ret <= 0)
  91                         EXIT(E_READ);
  92                 count += ret;
  93         }
  94 }
  95
  96 /*
  97  * set_alsa_params - Prepare the PCM handle for writing
  98  *
  99  * Install PCM software and hardware configuration. Exit on errors.
 100  */
 101 static void set_alsa_params(void)
 102 {
 103         snd_pcm_hw_params_t *hwparams;
 104         snd_pcm_sw_params_t *swparams;
 105         snd_pcm_uframes_t buffer_size, xfer_align, start_threshold,
 106                 stop_threshold;
 107         unsigned buffer_time = 0;
 108         int err;
 109
 110         snd_pcm_hw_params_alloca(&hwparams);
 111         snd_pcm_sw_params_alloca(&swparams);
 112         if (snd_pcm_hw_params_any(handle, hwparams) < 0)
 113                 EXIT(E_BROKEN_CONF);
 114         if (snd_pcm_hw_params_set_access(handle, hwparams,
 115                         SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
 116                 EXIT(E_ACCESS_TYPE);
 117         if (snd_pcm_hw_params_set_format(handle, hwparams, FORMAT) < 0)
 118                 EXIT(E_SAMPLE_FORMAT);
 119         if (snd_pcm_hw_params_set_channels(handle, hwparams, conf.channels_arg) < 0)
 120                 EXIT(E_CHANNEL_COUNT);
 121         if (snd_pcm_hw_params_set_rate_near(handle, hwparams,
 122                         (unsigned int*) &conf.sample_rate_arg, 0) < 0)
 123                 EXIT(E_SET_RATE);
 124         err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, 0);
 125         if (err < 0 || !buffer_time)
 126                 EXIT(E_GET_BUFFER_TIME);
 127         PARA_DEBUG_LOG("buffer time: %d\n", buffer_time);
 128         if (snd_pcm_hw_params_set_buffer_time_near(handle, hwparams,
 129                         &buffer_time, 0) < 0)
 130                 EXIT(E_SET_BUFFER_TIME);
 131         if (snd_pcm_hw_params(handle, hwparams) < 0)
 132                 EXIT(E_HW_PARAMS);
 133         snd_pcm_hw_params_get_period_size(hwparams, &chunk_size, 0);
 134         snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
 135         PARA_DEBUG_LOG("buffer size: %lu, period_size: %lu\n", buffer_size, chunk_size);
 136         if (chunk_size == buffer_size)
 137                 EXIT(E_BAD_PERIOD);
 138         snd_pcm_sw_params_current(handle, swparams);
 139         err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
 140         if (err < 0 || !xfer_align)
 141                 EXIT(E_GET_XFER);
 142 //      snd_pcm_sw_params_set_sleep_min(handle, swparams, 0);
 143         snd_pcm_sw_params_set_avail_min(handle, swparams, chunk_size);
 144         /* round to closest transfer boundary */
 145         start_threshold = (buffer_size / xfer_align) * xfer_align;
 146         if (start_threshold < 1)
 147                 start_threshold = 1;
 148         if (snd_pcm_sw_params_set_start_threshold(handle, swparams,
 149                         start_threshold) < 0)
 150                 EXIT(E_START_THRESHOLD);
 151         stop_threshold = buffer_size;
 152         if (snd_pcm_sw_params_set_stop_threshold(handle, swparams,
 153                         stop_threshold) < 0)
 154                 EXIT(E_STOP_THRESHOLD);
 155         if (snd_pcm_sw_params_set_xfer_align(handle, swparams, xfer_align) < 0)
 156                 EXIT(E_SET_XFER);
 157         if (snd_pcm_sw_params(handle, swparams) < 0)
 158                 EXIT(E_SW_PARAMS);
 159         bytes_per_frame = snd_pcm_format_physical_width(FORMAT) * conf.channels_arg / 8;
 160 }
 161
 162 /*
 163  * pcm_write - push out pcm frames
 164  * \param data pointer do data to be written
 165  * \param count number of frames
 166  *
 167  * \return Number of bytes written. Exit on errors.
 168  */
 169 static snd_pcm_sframes_t pcm_write(u_char *data, size_t count)
 170 {
 171         snd_pcm_sframes_t r, result = 0;
 172         while (count > 0) {
 173                 /* write interleaved frames */
 174                 r = snd_pcm_writei(handle, data, count);
 175                 if (r < 0)
 176                         PARA_ERROR_LOG("write error: %s\n", snd_strerror(r));
 177                 if (r == -EAGAIN || (r >= 0 && r < count))
 178                         snd_pcm_wait(handle, 1);
 179                 else if (r == -EPIPE)
 180                         snd_pcm_prepare(handle);
 181                 else if (r < 0)
 182                         EXIT(E_WRITE);
 183                 if (r > 0) {
 184                         result += r;
 185                         count -= r;
 186                         data += r * bytes_per_frame;
 187                 }
 188         }
 189         return result;
 190 }
 191
 192 /*
 193  * start_time_in_future - check if current time is later than start_time
 194  * \param diff pointer to write remaining time to
 195  *
 196  * If start_time was not given, or current time is later than given
 197  * start_time, return 0. Otherwise, return 1 and write the time
 198  * difference between current time and start_time to diff. diff may be
 199  * NULL.
 200  *
 201  */
 202 static int start_time_in_future(struct timeval *diff)
 203 {
 204         struct timeval now;
 205
 206         if (!conf.start_time_given)
 207                 return 0;
 208         gettimeofday(&now, NULL);
 209         return tv_diff(start_time, &now, diff) > 0? 1 : 0;
 210 }
 211
 212 /*
 213  * do_initial_delay - sleep until time given at command line
 214  *
 215  * This is called if the initial buffer is filled. It returns
 216  * immediately if no start_time was given at the command line
 217  * or if the given start time is in the past.
 218  *
 219  */
 220 static void do_initial_delay(struct timeval *delay)
 221 {
 222         do
 223                 para_select(1, NULL, NULL, delay);
 224         while (start_time_in_future(delay));
 225 }
 226
 227 /*
 228  * play_pcm - play raw pcm data
 229  * \param loaded number of bytes already loaded
 230  *
 231  * If start_time was given, prebuffer data until buffer is full or
 232  * start_time is reached. In any case, do not start playing before
 233  * start_time.
 234  */
 235 static void play_pcm(size_t loaded)
 236 {
 237         size_t chunk_bytes, bufsize, written = 0, prebuf_size;
 238         ssize_t ret;
 239         unsigned char *p;
 240         struct timeval delay;
 241
 242         set_alsa_params();
 243         chunk_bytes = chunk_size * bytes_per_frame;
 244         bufsize = (conf.bufsize_arg * 1024 / chunk_bytes) * chunk_bytes;
 245         audiobuf = realloc(audiobuf, bufsize);
 246         if (!audiobuf)
 247                 EXIT(E_MEM);
 248         prebuf_size = conf.prebuffer_arg * bufsize / 100;
 249 again:
 250         if (!written) {
 251                 if (loaded < prebuf_size)
 252                         goto read;
 253                 if (start_time && start_time_in_future(&delay)) {
 254                         do_initial_delay(&delay);
 255                         start_time = NULL;
 256                 }
 257         }
 258         p = audiobuf;
 259         while (loaded >= chunk_bytes) {
 260                 ret = pcm_write(p, chunk_size) * bytes_per_frame;
 261                 p += ret;
 262                 written += ret;
 263                 loaded -= ret;
 264         }
 265         if (loaded && p != audiobuf)
 266                 memcpy(audiobuf, p, loaded);
 267 read:
 268         ret = read(STDIN_FILENO, audiobuf + loaded, bufsize - loaded);
 269         if (ret < 0)
 270                 EXIT(E_READ);
 271         if (ret) {
 272                 loaded += ret;
 273                 goto again;
 274         }
 275         snd_pcm_drain(handle);
 276 }
 277
 278 /*
 279  * check_wave - test if audio buffer contains a valid wave header
 280  *
 281  * If not, return 0, otherwise, store number of channels and sample rate
 282  * in struct conf and return WAV_HEADER_LEN.
 283  */
 284 static size_t check_wave(void)
 285 {
 286         unsigned char *a = audiobuf;
 287         if (a[0] != 'R' || a[1] != 'I' || a[2] != 'F' || a[3] != 'F')
 288                 return WAV_HEADER_LEN;
 289         conf.channels_arg = (unsigned) a[22];
 290         conf.sample_rate_arg = a[24] + (a[25] << 8) + (a[26] << 16) + (a[27] << 24);
 291         return 0;
 292 }
 293
 294 int main(int argc, char *argv[])
 295 {
 296         snd_pcm_info_t *info;
 297         snd_output_t *log;
 298         struct timeval tv;
 299         int err;
 300
 301         cmdline_parser(argc, argv, &conf);
 302         if (conf.start_time_given) {
 303                 if (sscanf(conf.start_time_arg, "%lu:%lu",
 304                                 &tv.tv_sec, &tv.tv_usec) != 2)
 305                         EXIT(E_SYNTAX);
 306                 start_time = &tv;
 307         }
 308         snd_pcm_info_alloca(&info);
 309         if (snd_output_stdio_attach(&log, stderr, 0) < 0)
 310                 EXIT(E_LOG);
 311         err = snd_pcm_open(&handle, conf.device_arg,
 312                 SND_PCM_STREAM_PLAYBACK, 0);
 313         if (err < 0)
 314                 EXIT(E_PCM_OPEN);
 315         if ((err = snd_pcm_info(handle, info)) < 0)
 316                 EXIT(E_SND_PCM_INFO);
 317         audiobuf = malloc(WAV_HEADER_LEN);
 318         read_wav_header();
 319         play_pcm(check_wave());
 320         snd_pcm_close(handle);
 321         free(audiobuf);
 322 //      snd_output_close(log);
 323         snd_config_update_free_global();
 324         return EXIT_SUCCESS;
 325 }