ref: 29c4dba087e245d7ff9dc33d276e660c1a94dff7
dir: /src/alsa.c/
#if defined(ALSA_PLAYER) /* * Copyright 1997 Jimen Ching And Sundry Contributors * This source code is freely redistributable and may be used for * any purpose. This copyright notice must be maintained. * Jimen Ching And Sundry Contributors are not * responsible for the consequences of using this software. */ /* Direct to ALSA sound driver * * added by Jimen Ching (jching@flex.com) 19990207 * based on info grabed from aplay.c in alsa-utils package. */ #include <unistd.h> #include <stdlib.h> #include <string.h> #include <stdio.h> #include <fcntl.h> #include <linux/asound.h> #include <sys/ioctl.h> #include "st.h" /* * Do anything required before you start reading samples. * Read file header. * Find out sampling rate, * size and encoding of samples, * mono/stereo/quad. */ int st_alsastartread(ft) ft_t ft; { int bps, fmt, size; snd_pcm_capture_info_t c_info; snd_pcm_format_t format; snd_pcm_capture_params_t c_params; memset(&c_info, 0, sizeof(c_info)); ioctl(fileno(ft->fp), SND_PCM_IOCTL_CAPTURE_INFO, &c_info); ft->file.count = 0; ft->file.pos = 0; ft->file.eof = 0; ft->file.size = c_info.buffer_size; if ((ft->file.buf = malloc (ft->file.size)) == NULL) { st_fail("unable to allocate output buffer of size %d", ft->file.size); return (ST_EOF); } if (ft->info.rate < c_info.min_rate) ft->info.rate = 2 * c_info.min_rate; else if (ft->info.rate > c_info.max_rate) ft->info.rate = c_info.max_rate; if (ft->info.channels == -1) ft->info.channels = c_info.min_channels; else if (ft->info.channels > c_info.max_channels) ft->info.channels = c_info.max_channels; if (ft->info.size == -1) { if ((c_info.hw_formats & SND_PCM_FMT_U8) || (c_info.hw_formats & SND_PCM_FMT_S8)) ft->info.size = ST_SIZE_BYTE; else ft->info.size = ST_SIZE_WORD; } if (ft->info.encoding == -1) { if ((c_info.hw_formats & SND_PCM_FMT_S16_LE) || (c_info.hw_formats & SND_PCM_FMT_S8)) ft->info.encoding = ST_ENCODING_SIGN2; else ft->info.encoding = ST_ENCODING_UNSIGNED; } if (ft->info.size == ST_SIZE_BYTE) { switch (ft->info.encoding) { case ST_ENCODING_SIGN2: if (!(c_info.hw_formats & SND_PCM_FMT_S8)) { st_fail("ALSA driver does not support signed byte samples"); return(ST_EOF); } fmt = SND_PCM_SFMT_S8; break; case ST_ENCODING_UNSIGNED: if (!(c_info.hw_formats & SND_PCM_FMT_U8)) { st_fail("ALSA driver does not support unsigned byte samples"); return(ST_EOF); } fmt = SND_PCM_SFMT_U8; break; default: st_fail("Hardware does not support %s output", st_encodings_str[ft->info.encoding]); return(ST_EOF); break; } } else { switch (ft->info.encoding) { case ST_ENCODING_SIGN2: if (!(c_info.hw_formats & SND_PCM_FMT_S16_LE)) st_fail("ALSA driver does not support signed word samples"); fmt = SND_PCM_SFMT_S16_LE; break; case ST_ENCODING_UNSIGNED: if (!(c_info.hw_formats & SND_PCM_FMT_U16_LE)) st_fail("ALSA driver does not support unsigned word samples"); fmt = SND_PCM_SFMT_U16_LE; break; default: st_fail("Hardware does not support %s output", st_encodings_str[ft->info.encoding]); return(ST_EOF); break; } } memset(&format, 0, sizeof(format)); format.format = fmt; format.rate = ft->info.rate; format.channels = ft->info.channels; ioctl(fileno(ft->fp), SND_PCM_IOCTL_CAPTURE_FORMAT, &format); size = ft->file.size; bps = format.rate * format.channels; if (ft->info.size == ST_SIZE_WORD) bps <<= 1; bps >>= 2; while (size > bps) size >>= 1; if (size < 16) size = 16; memset(&c_params, 0, sizeof(c_params)); c_params.fragment_size = size; c_params.fragments_min = 1; ioctl(fileno(ft->fp), SND_PCM_IOCTL_CAPTURE_PARAMS, &c_params); /* Change to non-buffered I/O */ setvbuf(ft->fp, NULL, _IONBF, sizeof(char) * ft->file.size); sigintreg(ft); /* Prepare to catch SIGINT */ return (ST_SUCCESS); } int st_alsastartwrite(ft) ft_t ft; { int bps, fmt, size; snd_pcm_playback_info_t p_info; snd_pcm_format_t format; snd_pcm_playback_params_t p_params; memset(&p_info, 0, sizeof(p_info)); ioctl(fileno(ft->fp), SND_PCM_IOCTL_PLAYBACK_INFO, &p_info); ft->file.pos = 0; ft->file.eof = 0; ft->file.size = p_info.buffer_size; if ((ft->file.buf = malloc (ft->file.size)) == NULL) { st_fail("unable to allocate output buffer of size %d", ft->file.size); return(ST_EOF); } if (ft->info.rate < p_info.min_rate) ft->info.rate = 2 * p_info.min_rate; else if (ft->info.rate > p_info.max_rate) ft->info.rate = p_info.max_rate; if (ft->info.channels == -1) ft->info.channels = p_info.min_channels; else if (ft->info.channels > p_info.max_channels) ft->info.channels = p_info.max_channels; if (ft->info.size == -1) { if ((p_info.hw_formats & SND_PCM_FMT_U8) || (p_info.hw_formats & SND_PCM_FMT_S8)) ft->info.size = ST_SIZE_BYTE; else ft->info.size = ST_SIZE_WORD; } if (ft->info.encoding == -1) { if ((p_info.hw_formats & SND_PCM_FMT_S16_LE) || (p_info.hw_formats & SND_PCM_FMT_S8)) ft->info.encoding = ST_ENCODING_SIGN2; else ft->info.encoding = ST_ENCODING_UNSIGNED; } if (ft->info.size == ST_SIZE_BYTE) { switch (ft->info.encoding) { case ST_ENCODING_SIGN2: if (!(p_info.hw_formats & SND_PCM_FMT_S8)) { st_fail("ALSA driver does not support signed byte samples"); return (ST_EOF); } fmt = SND_PCM_SFMT_S8; break; case ST_ENCODING_UNSIGNED: if (!(p_info.hw_formats & SND_PCM_FMT_U8)) { st_fail("ALSA driver does not support unsigned byte samples"); return (ST_EOF); } fmt = SND_PCM_SFMT_U8; break; default: st_fail("Hardware does not support %s output", st_encodings_str[ft->info.encoding]); return(ST_EOF); break; } } else { switch (ft->info.encoding) { case ST_ENCODING_SIGN2: if (!(p_info.hw_formats & SND_PCM_FMT_S16_LE)) { st_fail("ALSA driver does not support signed word samples"); return (ST_EOF); } fmt = SND_PCM_SFMT_S16_LE; break; case ST_ENCODING_UNSIGNED: if (!(p_info.hw_formats & SND_PCM_FMT_U16_LE)) { st_fail("ALSA driver does not support unsigned word samples"); return(ST_EOF); } fmt = SND_PCM_SFMT_U16_LE; break; default: st_fail("Hardware does not support %s output", st_encodings_str[ft->info.encoding]); return(ST_EOF); break; } } memset(&format, 0, sizeof(format)); format.format = fmt; format.rate = ft->info.rate; format.channels = ft->info.channels; ioctl(fileno(ft->fp), SND_PCM_IOCTL_PLAYBACK_FORMAT, &format); size = ft->file.size; bps = format.rate * format.channels; if (ft->info.size == ST_SIZE_WORD) bps <<= 1; bps >>= 2; while (size > bps) size >>= 1; if (size < 16) size = 16; memset(&p_params, 0, sizeof(p_params)); p_params.fragment_size = size; p_params.fragments_max = -1; p_params.fragments_room = 1; ioctl(fileno(ft->fp), SND_PCM_IOCTL_PLAYBACK_PARAMS, &p_params); /* Change to non-buffered I/O */ setvbuf(ft->fp, NULL, _IONBF, sizeof(char) * ft->file.size); return(ST_SUCCESS); } #endif