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 snd_pcm_uframes_t chunk_size;
  65 static unsigned char *audiobuf;
  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  * open and prepare the PCM handle for writing
  98  *
  99  * Install PCM software and hardware configuration. Exit on errors.
 100  */
 101 static void alsa_init(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         snd_pcm_info_t *info;
 110         snd_output_t *log;
 111
 112         snd_pcm_info_alloca(&info);
 113         if (snd_output_stdio_attach(&log, stderr, 0) < 0)
 114                 EXIT(E_LOG);
 115         err = snd_pcm_open(&handle, conf.device_arg,
 116                 SND_PCM_STREAM_PLAYBACK, 0);
 117         if (err < 0)
 118                 EXIT(E_PCM_OPEN);
 119         if ((err = snd_pcm_info(handle, info)) < 0)
 120                 EXIT(E_SND_PCM_INFO);
 121
 122         snd_pcm_hw_params_alloca(&hwparams);
 123         snd_pcm_sw_params_alloca(&swparams);
 124         if (snd_pcm_hw_params_any(handle, hwparams) < 0)
 125                 EXIT(E_BROKEN_CONF);
 126         if (snd_pcm_hw_params_set_access(handle, hwparams,
 127                         SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
 128                 EXIT(E_ACCESS_TYPE);
 129         if (snd_pcm_hw_params_set_format(handle, hwparams, FORMAT) < 0)
 130                 EXIT(E_SAMPLE_FORMAT);
 131         if (snd_pcm_hw_params_set_channels(handle, hwparams, conf.channels_arg) < 0)
 132                 EXIT(E_CHANNEL_COUNT);
 133         if (snd_pcm_hw_params_set_rate_near(handle, hwparams,
 134                         (unsigned int*) &conf.sample_rate_arg, 0) < 0)
 135                 EXIT(E_SET_RATE);
 136         err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, 0);
 137         if (err < 0 || !buffer_time)
 138                 EXIT(E_GET_BUFFER_TIME);
 139         PARA_DEBUG_LOG("buffer time: %d\n", buffer_time);
 140         if (snd_pcm_hw_params_set_buffer_time_near(handle, hwparams,
 141                         &buffer_time, 0) < 0)
 142                 EXIT(E_SET_BUFFER_TIME);
 143         if (snd_pcm_hw_params(handle, hwparams) < 0)
 144                 EXIT(E_HW_PARAMS);
 145         snd_pcm_hw_params_get_period_size(hwparams, &chunk_size, 0);
 146         snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
 147         PARA_DEBUG_LOG("buffer size: %lu, period_size: %lu\n", buffer_size, chunk_size);
 148         if (chunk_size == buffer_size)
 149                 EXIT(E_BAD_PERIOD);
 150         snd_pcm_sw_params_current(handle, swparams);
 151         err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
 152         if (err < 0 || !xfer_align)
 153                 EXIT(E_GET_XFER);
 154 //      snd_pcm_sw_params_set_sleep_min(handle, swparams, 0);
 155         snd_pcm_sw_params_set_avail_min(handle, swparams, chunk_size);
 156         /* round to closest transfer boundary */
 157         start_threshold = (buffer_size / xfer_align) * xfer_align;
 158         if (start_threshold < 1)
 159                 start_threshold = 1;
 160         if (snd_pcm_sw_params_set_start_threshold(handle, swparams,
 161                         start_threshold) < 0)
 162                 EXIT(E_START_THRESHOLD);
 163         stop_threshold = buffer_size;
 164         if (snd_pcm_sw_params_set_stop_threshold(handle, swparams,
 165                         stop_threshold) < 0)
 166                 EXIT(E_STOP_THRESHOLD);
 167         if (snd_pcm_sw_params_set_xfer_align(handle, swparams, xfer_align) < 0)
 168                 EXIT(E_SET_XFER);
 169         if (snd_pcm_sw_params(handle, swparams) < 0)
 170                 EXIT(E_SW_PARAMS);
 171         bytes_per_frame = snd_pcm_format_physical_width(FORMAT) * conf.channels_arg / 8;
 172 }
 173
 174 /**
 175  * push out pcm frames
 176  * \param data pointer do data to be written
 177  * \param nbytes number of bytes (not frames)
 178  *
 179  * \return Number of bytes written. Exit on errors.
 180  */
 181 int alsa_write(u_char *data, size_t nbytes)
 182 {
 183         size_t count = nbytes / bytes_per_frame;
 184         snd_pcm_sframes_t r, result = 0;
 185         while (count > 0) {
 186                 /* write interleaved frames */
 187                 r = snd_pcm_writei(handle, data, count);
 188                 if (r < 0)
 189                         PARA_ERROR_LOG("write error: %s\n", snd_strerror(r));
 190                 if (r == -EAGAIN || (r >= 0 && r < count))
 191                         snd_pcm_wait(handle, 1);
 192                 else if (r == -EPIPE)
 193                         snd_pcm_prepare(handle);
 194                 else if (r < 0)
 195                         EXIT(E_WRITE);
 196                 if (r > 0) {
 197                         result += r;
 198                         count -= r;
 199                         data += r * bytes_per_frame;
 200                 }
 201         }
 202         return result * bytes_per_frame;
 203 }
 204
 205 void alsa_shutdown(void)
 206 {
 207         snd_pcm_drain(handle);
 208         snd_pcm_close(handle);
 209         snd_config_update_free_global();
 210 }
 211
 212 /*
 213  * start_time_in_future - check if current time is later than start_time
 214  * \param diff pointer to write remaining time to
 215  *
 216  * If start_time was not given, or current time is later than given
 217  * start_time, return 0. Otherwise, return 1 and write the time
 218  * difference between current time and start_time to diff. diff may be
 219  * NULL.
 220  *
 221  */
 222 static int start_time_in_future(struct timeval *diff)
 223 {
 224         struct timeval now;
 225
 226         if (!conf.start_time_given)
 227                 return 0;
 228         gettimeofday(&now, NULL);
 229         return tv_diff(start_time, &now, diff) > 0? 1 : 0;
 230 }
 231
 232 /*
 233  * do_initial_delay - sleep until time given at command line
 234  *
 235  * This is called if the initial buffer is filled. It returns
 236  * immediately if no start_time was given at the command line
 237  * or if the given start time is in the past.
 238  *
 239  */
 240 static void do_initial_delay(struct timeval *delay)
 241 {
 242         do
 243                 para_select(1, NULL, NULL, delay);
 244         while (start_time_in_future(delay));
 245 }
 246
 247 /*
 248  * play_pcm - play raw pcm data
 249  * \param loaded number of bytes already loaded
 250  *
 251  * If start_time was given, prebuffer data until buffer is full or
 252  * start_time is reached. In any case, do not start playing before
 253  * start_time.
 254  */
 255 static void play_pcm(size_t loaded)
 256 {
 257         size_t chunk_bytes, bufsize, written = 0, prebuf_size;
 258         ssize_t ret;
 259         unsigned char *p;
 260         struct timeval delay;
 261
 262         alsa_init();
 263         chunk_bytes = chunk_size * bytes_per_frame;
 264         bufsize = (conf.bufsize_arg * 1024 / chunk_bytes) * chunk_bytes;
 265         audiobuf = realloc(audiobuf, bufsize);
 266         if (!audiobuf)
 267                 EXIT(E_MEM);
 268         prebuf_size = conf.prebuffer_arg * bufsize / 100;
 269 again:
 270         if (!written) {
 271                 if (loaded < prebuf_size)
 272                         goto read;
 273                 if (start_time && start_time_in_future(&delay)) {
 274                         do_initial_delay(&delay);
 275                         start_time = NULL;
 276                 }
 277         }
 278         p = audiobuf;
 279         while (loaded >= chunk_bytes) {
 280                 ret = alsa_write(p, chunk_bytes);
 281                 p += ret;
 282                 written += ret;
 283                 loaded -= ret;
 284         }
 285         if (loaded && p != audiobuf)
 286                 memmove(audiobuf, p, loaded);
 287 read:
 288         ret = read(STDIN_FILENO, audiobuf + loaded, bufsize - loaded);
 289         if (ret < 0)
 290                 EXIT(E_READ);
 291         if (ret) {
 292                 loaded += ret;
 293                 goto again;
 294         }
 295         alsa_shutdown();
 296 }
 297
 298 /*
 299  * check_wave - test if audio buffer contains a valid wave header
 300  *
 301  * If not, return 0, otherwise, store number of channels and sample rate
 302  * in struct conf and return WAV_HEADER_LEN.
 303  */
 304 static size_t check_wave(void)
 305 {
 306         unsigned char *a = audiobuf;
 307         if (a[0] != 'R' || a[1] != 'I' || a[2] != 'F' || a[3] != 'F')
 308                 return WAV_HEADER_LEN;
 309         conf.channels_arg = (unsigned) a[22];
 310         conf.sample_rate_arg = a[24] + (a[25] << 8) + (a[26] << 16) + (a[27] << 24);
 311         return 0;
 312 }
 313
 314 int main(int argc, char *argv[])
 315 {
 316         struct timeval tv;
 317
 318         cmdline_parser(argc, argv, &conf);
 319         if (conf.start_time_given) {
 320                 if (sscanf(conf.start_time_arg, "%lu:%lu",
 321                                 &tv.tv_sec, &tv.tv_usec) != 2)
 322                         EXIT(E_SYNTAX);
 323                 start_time = &tv;
 324         }
 325         audiobuf = malloc(WAV_HEADER_LEN);
 326         read_wav_header();
 327         play_pcm(check_wave());
 328         free(audiobuf);
 329         return EXIT_SUCCESS;
 330 }