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 #include "string.h"
  32 #include "error.h"
  33
  34 #define FORMAT SND_PCM_FORMAT_S16_LE
  35
  36 struct private_alsa_data {
  37         snd_pcm_t *handle;
  38         size_t bytes_per_frame;
  39 };
  40
  41 static unsigned char *audiobuf;
  42 static struct timeval *start_time;
  43 static struct gengetopt_args_info conf;
  44
  45 INIT_PLAY_ERRLISTS;
  46
  47 void para_log(__a_unused int ll, const char* fmt,...)
  48 {
  49         va_list argp;
  50
  51         va_start(argp, fmt);
  52         vfprintf(stderr, fmt, argp);
  53         va_end(argp);
  54 }
  55
  56 /**
  57  * read WAV_HEADER_LEN bytes from stdin to audio buffer
  58  *
  59  * \return -E_READ_HDR on errors and on eof before WAV_HEADER_LEN could be
  60  * read. A positive return value indicates success.
  61  */
  62 static int read_wav_header(void)
  63 {
  64         ssize_t ret, count = 0;
  65
  66         while (count < WAV_HEADER_LEN) {
  67                 ret = read(STDIN_FILENO, audiobuf + count, WAV_HEADER_LEN - count);
  68                 if (ret <= 0)
  69                         return -E_READ_HDR;
  70                 count += ret;
  71         }
  72         return 1;
  73 }
  74
  75 /*
  76  * open and prepare the PCM handle for writing
  77  *
  78  * Install PCM software and hardware configuration. Exit on errors.
  79  */
  80 static int alsa_init(void **private_data)
  81 {
  82         snd_pcm_hw_params_t *hwparams;
  83         snd_pcm_sw_params_t *swparams;
  84         snd_pcm_uframes_t buffer_size, xfer_align, start_threshold,
  85                 stop_threshold;
  86         unsigned buffer_time = 0;
  87         int err;
  88         snd_pcm_info_t *info;
  89         snd_output_t *log;
  90         snd_pcm_uframes_t period_size;
  91         struct private_alsa_data *pad = para_malloc(sizeof(struct private_alsa_data));
  92         *private_data = pad;
  93
  94         snd_pcm_info_alloca(&info);
  95         if (snd_output_stdio_attach(&log, stderr, 0) < 0)
  96                 return -E_ALSA_LOG;
  97         err = snd_pcm_open(&pad->handle, conf.device_arg,
  98                 SND_PCM_STREAM_PLAYBACK, 0);
  99         if (err < 0)
 100                 return -E_PCM_OPEN;
 101         if ((err = snd_pcm_info(pad->handle, info)) < 0)
 102                 return -E_SND_PCM_INFO;
 103
 104         snd_pcm_hw_params_alloca(&hwparams);
 105         snd_pcm_sw_params_alloca(&swparams);
 106         if (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
 107                 return -E_BROKEN_CONF;
 108         if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
 109                         SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
 110                 return -E_ACCESS_TYPE;
 111         if (snd_pcm_hw_params_set_format(pad->handle, hwparams, FORMAT) < 0)
 112                 return -E_SAMPLE_FORMAT;
 113         if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
 114                         conf.channels_arg) < 0)
 115                 return -E_CHANNEL_COUNT;
 116         if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
 117                         (unsigned int*) &conf.sample_rate_arg, 0) < 0)
 118                 return -E_SET_RATE;
 119         err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, 0);
 120         if (err < 0 || !buffer_time)
 121                 return -E_GET_BUFFER_TIME;
 122         PARA_DEBUG_LOG("buffer time: %d\n", buffer_time);
 123         if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
 124                         &buffer_time, 0) < 0)
 125                 return -E_SET_BUFFER_TIME;
 126         if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
 127                 return -E_HW_PARAMS;
 128         snd_pcm_hw_params_get_period_size(hwparams, &period_size, 0);
 129         snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
 130         PARA_DEBUG_LOG("buffer size: %lu, period_size: %lu\n", buffer_size, period_size);
 131         if (period_size == buffer_size)
 132                 return -E_BAD_PERIOD;
 133         snd_pcm_sw_params_current(pad->handle, swparams);
 134         err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
 135         if (err < 0 || !xfer_align)
 136                 return -E_GET_XFER;
 137         snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
 138         /* round to closest transfer boundary */
 139         start_threshold = (buffer_size / xfer_align) * xfer_align;
 140         if (start_threshold < 1)
 141                 start_threshold = 1;
 142         if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
 143                         start_threshold) < 0)
 144                 return -E_START_THRESHOLD;
 145         stop_threshold = buffer_size;
 146         if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
 147                         stop_threshold) < 0)
 148                 return -E_STOP_THRESHOLD;
 149         if (snd_pcm_sw_params_set_xfer_align(pad->handle, swparams,
 150                         xfer_align) < 0)
 151                 return -E_SET_XFER;
 152         if (snd_pcm_sw_params(pad->handle, swparams) < 0)
 153                 return -E_SW_PARAMS;
 154         pad->bytes_per_frame = snd_pcm_format_physical_width(FORMAT)
 155                 * conf.channels_arg / 8;
 156         return period_size * pad->bytes_per_frame;
 157 }
 158
 159 /**
 160  * push out pcm frames
 161  * \param data pointer do data to be written
 162  * \param nbytes number of bytes (not frames)
 163  *
 164  * \return Number of bytes written, -E_ALSA_WRITE on errors.
 165  */
 166 static int alsa_write(u_char *data, size_t nbytes, void *private_data)
 167 {
 168         struct private_alsa_data *pad = private_data;
 169         size_t frames = nbytes / pad->bytes_per_frame;
 170         snd_pcm_sframes_t r, result = 0;
 171
 172         while (frames > 0) {
 173                 /* write interleaved frames */
 174                 r = snd_pcm_writei(pad->handle, data, frames);
 175                 if (r < 0)
 176                         PARA_ERROR_LOG("write error: %s\n", snd_strerror(r));
 177                 if (r == -EAGAIN || (r >= 0 && r < frames))
 178                         snd_pcm_wait(pad->handle, 1);
 179                 else if (r == -EPIPE)
 180                         snd_pcm_prepare(pad->handle);
 181                 else if (r < 0)
 182                         return -E_ALSA_WRITE;
 183                 if (r > 0) {
 184                         result += r;
 185                         frames -= r;
 186                         data += r * pad->bytes_per_frame;
 187                 }
 188         }
 189         return result * pad->bytes_per_frame;
 190 }
 191
 192 static void alsa_shutdown(void *private_data)
 193 {
 194         struct private_alsa_data *pad = private_data;
 195         snd_pcm_drain(pad->handle);
 196         snd_pcm_close(pad->handle);
 197         snd_config_update_free_global();
 198 }
 199
 200 /**
 201  * check if current time is later than start_time
 202  * \param diff pointer to write remaining time to
 203  *
 204  * If start_time was not given, or current time is later than given
 205  * start_time, return 0. Otherwise, return 1 and write the time
 206  * difference between current time and start_time to diff. diff may be
 207  * NULL.
 208  *
 209  */
 210 static int start_time_in_future(struct timeval *diff)
 211 {
 212         struct timeval now;
 213
 214         if (!conf.start_time_given)
 215                 return 0;
 216         gettimeofday(&now, NULL);
 217         return tv_diff(start_time, &now, diff) > 0? 1 : 0;
 218 }
 219
 220 /**
 221  * sleep until time given at command line
 222  *
 223  * This is called if the initial buffer is filled. It returns
 224  * immediately if no start_time was given at the command line
 225  * or if the given start time is in the past.
 226  *
 227  */
 228 static void do_initial_delay(struct timeval *delay)
 229 {
 230         do
 231                 para_select(1, NULL, NULL, delay);
 232         while (start_time_in_future(delay));
 233 }
 234
 235 /**
 236  * play raw pcm data
 237  * \param loaded number of bytes already loaded
 238  *
 239  * If start_time was given, prebuffer data until buffer is full or
 240  * start_time is reached. In any case, do not start playing before
 241  * start_time.
 242  *
 243  * \return positive on success, negative on errors.
 244  */
 245 static int play_pcm(size_t loaded)
 246 {
 247         size_t bufsize, written = 0, prebuf_size;
 248         unsigned char *p;
 249         struct timeval delay;
 250         void *private_data;
 251         int chunk_bytes, ret = alsa_init(&private_data);
 252
 253         if (ret < 0)
 254                 goto out;
 255         chunk_bytes = ret;
 256         bufsize = (conf.bufsize_arg * 1024 / chunk_bytes) * chunk_bytes;
 257         audiobuf = para_realloc(audiobuf, bufsize);
 258         prebuf_size = conf.prebuffer_arg * bufsize / 100;
 259 again:
 260         if (!written) {
 261                 if (loaded < prebuf_size)
 262                         goto read;
 263                 if (start_time && start_time_in_future(&delay)) {
 264                         do_initial_delay(&delay);
 265                         start_time = NULL;
 266                 }
 267         }
 268         p = audiobuf;
 269         while (loaded >= chunk_bytes) {
 270                 ret = alsa_write(p, chunk_bytes, private_data);
 271                 if (ret < 0)
 272                         goto out;
 273                 p += ret;
 274                 written += ret;
 275                 loaded -= ret;
 276         }
 277         if (loaded && p != audiobuf)
 278                 memmove(audiobuf, p, loaded);
 279 read:
 280         ret = read(STDIN_FILENO, audiobuf + loaded, bufsize - loaded);
 281         if (ret < 0) {
 282                 ret = -E_READ_STDIN;
 283                 goto out;
 284         }
 285         if (ret) {
 286                 loaded += ret;
 287                 goto again;
 288         }
 289         ret = 1;
 290 out:
 291         alsa_shutdown(private_data);
 292         return ret;
 293 }
 294
 295 /**
 296  * test if audio buffer contains a valid wave header
 297  *
 298  * \return If not, return 0, otherwise, store number of channels and sample rate
 299  * in struct conf and return WAV_HEADER_LEN.
 300  */
 301 static size_t check_wave(void)
 302 {
 303         unsigned char *a = audiobuf;
 304         if (a[0] != 'R' || a[1] != 'I' || a[2] != 'F' || a[3] != 'F')
 305                 return WAV_HEADER_LEN;
 306         conf.channels_arg = (unsigned) a[22];
 307         conf.sample_rate_arg = a[24] + (a[25] << 8) + (a[26] << 16) + (a[27] << 24);
 308         return 0;
 309 }
 310
 311 int main(int argc, char *argv[])
 312 {
 313         struct timeval tv;
 314         int ret;
 315
 316         cmdline_parser(argc, argv, &conf);
 317         if (conf.start_time_given) {
 318                 ret = -E_PLAY_SYNTAX;
 319                 if (sscanf(conf.start_time_arg, "%lu:%lu",
 320                                 &tv.tv_sec, &tv.tv_usec) != 2)
 321                         goto out;
 322                 start_time = &tv;
 323         }
 324         audiobuf = para_malloc(WAV_HEADER_LEN);
 325         ret = read_wav_header();
 326         if (ret < 0)
 327                 goto out;
 328         ret = play_pcm(check_wave());
 329 out:
 330         free(audiobuf);
 331         if (ret < 0)
 332                 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
 333         return ret;
 334 }