Re: ALSA support

Sound has never worked correctly for me since moving to a Linux 2.6 kernel. Maybe I just have an ultra-cheap sound card. In any case, the existing linuxplay.c file doesn't do what my system wants. I wind up with distorted sound, or no sound at all, and lots of warnings that too few bytes were written to the sound device. Here's a quick attempt by me to add support for ALSA. It isn't complete. I'm posting it here to ask for comments and testers. This patch "works", in the sense that I can successfully build with it, and then I can play all of the sounds that come with Gnus. I don't yet know what to do with the volume argument to play-sound and play-sound-file, and the way I manage sound files is probably horrible in some way. Furthermore, I'm not sure if the configure magic is right; does the existence of the ALSA library imply that it should be used?

it out. Index: configure.ac =================================================================== RCS file: /pack/xemacscvs/XEmacs/xemacs/configure.ac,v retrieving revision 1.35 diff -d -u -r1.35 configure.ac --- configure.ac 2006/02/27 16:29:06 1.35 +++ configure.ac 2006/03/20 21:44:37 ＠＠ -5079,6 +5079,16 ＠＠ esac fi + dnl Check for ALSA sound support + if test -z "$sound_found"; then + AC_CHECK_HEADER([alsa/pcm.h], [ + sound_found=yes + AC_CHECK_LIB(asound, snd_pcm_open, + [with_native_sound_lib=-lasound + XE_ADD_OBJS(alsaplay.o)], + [sound_found=no])]) + fi + dnl Check for Linux/BSD native sound (also on recent Cygwins) if test -z "$sound_found"; then for dir in "machine" "sys" "linux"; do /* Play sound with the ALSA library Copyright (C) 2006 Jerry James. This file is part of XEmacs. XEmacs is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. XEmacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with XEmacs; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Synched up with: Not in FSF. */ #include <config.h> #include "lisp.h" #include "sound.h" #include "sysfile.h" #include <alsa/input.h> #include <alsa/output.h> #include <alsa/conf.h> #include <alsa/global.h> #include <alsa/pcm.h> #include <alsa/error.h> #define WORD_LE(arr,start) (arr[start] + (arr[start + 1] << 8) + \ (arr[start + 2] << 16) + (arr[start + 3] << 24)) #define WORD_BE(arr,start) ((arr[start] << 24) + (arr[start + 1] << 16) + \ (arr[start + 2] << 8) + arr[start + 3]) /* This function was largely stolen from miscplay.c. */ static snd_pcm_format_t analyze_format (Binbyte *format, int *speed, int *tracks) { /* Keep compatibility with Linux 68k, etc. by not relying on byte-sex */ if (!memcmp (format, "Creative Voice File\x1A\x1A\x00", 22) && (format[22] + (format[23] << 8)) == ((0x1233 - format[24] - (format[25] << 8)) & 0xFFFF)) { /* VOC */ *speed = 8000; *tracks = 2; return SND_PCM_FORMAT_U8; } else if (!memcmp (format, "RIFF", 4) && !memcmp (format + 8, "WAVEfmt ", 8)) { /* WAVE */ *speed = WORD_LE (format, 24); *tracks = format[22]; return format[32] / format[22] == 1 ? SND_PCM_FORMAT_U8 : SND_PCM_FORMAT_S16_LE; } else if (!memcmp (format, ".snd", 4)) { /* Sun/NeXT Audio (big endian) */ if (WORD_BE (format, 4) < 24) { *speed = 8000; *tracks = 1; return SND_PCM_FORMAT_MU_LAW; } *speed = WORD_BE (format, 16); *tracks = format[23]; if (!memcmp (format + 12, "\000\000\000", 3)) { switch (format[15]) { case 1: case 17: case 29: return SND_PCM_FORMAT_MU_LAW; case 2: return SND_PCM_FORMAT_S8; case 3: return SND_PCM_FORMAT_S16_BE; case 4: return SND_PCM_FORMAT_S24_BE; case 5: return SND_PCM_FORMAT_S32_BE; case 23: case 24: case 25: case 26: return SND_PCM_FORMAT_IMA_ADPCM; case 27: return SND_PCM_FORMAT_A_LAW; default: break; } } return SND_PCM_FORMAT_UNKNOWN; } else if (!memcmp (format, ".sd", 4)) { /* DEC Audio (little endian) */ if (WORD_LE (format, 4) < 24) { *speed = 8000; *tracks = 1; return SND_PCM_FORMAT_MU_LAW; } *speed = WORD_LE (format, 16); *tracks = format[20]; if (!memcmp (format + 13, "\000\000\000", 3)) { switch (format[12]) { case 1: case 17: case 29: return SND_PCM_FORMAT_MU_LAW; case 2: return SND_PCM_FORMAT_S8; case 3: return SND_PCM_FORMAT_S16_LE; case 4: return SND_PCM_FORMAT_S24_LE; case 5: return SND_PCM_FORMAT_S32_LE; case 23: case 24: case 25: case 26: return SND_PCM_FORMAT_IMA_ADPCM; case 27: return SND_PCM_FORMAT_A_LAW; default: break; } } return SND_PCM_FORMAT_UNKNOWN; } else { *speed = 8000; *tracks = 1; return SND_PCM_FORMAT_U8; } } int play_sound_data (Binbyte *data, int length, int volume) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *hwparams; snd_pcm_format_t format; int speed, tracks, err; if ((err = snd_pcm_open (&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0)) < 0) goto error_early; snd_pcm_hw_params_alloca (&hwparams); if ((err = snd_pcm_hw_params_any (pcm_handle, hwparams)) < 0) goto error; format = analyze_format (data, &speed, &tracks); if ((err = snd_pcm_hw_params_set_access (pcm_handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) goto error; if ((err = snd_pcm_hw_params_set_format (pcm_handle, hwparams, format)) < 0) goto error; if ((err = snd_pcm_hw_params_set_rate (pcm_handle, hwparams, speed, 0)) < 0) goto error; if ((err = snd_pcm_hw_params_set_channels (pcm_handle, hwparams, tracks)) < 0) goto error; if ((err = snd_pcm_hw_params (pcm_handle, hwparams)) < 0) goto error; if ((err = snd_pcm_prepare (pcm_handle)) < 0) goto error; if ((err = snd_pcm_writei (pcm_handle, data, length)) < 0) goto error; snd_pcm_close (pcm_handle); return 1; error: snd_pcm_close (pcm_handle); error_early: sound_perror (snd_strerror (err)); return 0; } void play_sound_file (Extbyte *sound_file, int volume) { Binbyte *data; int fd; struct stat st; fd = open (sound_file, O_RDONLY, 0); if (fd < 0) { sound_perror (sound_file); return; } qxe_fstat (fd, &st); data = xnew_array (Binbyte, st.st_size); read (fd, data, st.st_size); play_sound_data (data, st.st_size, volume); xfree (data, Binbyte); } Regards, -- Jerry James, Assistant Professor james(a)xemacs.org Computer Science Department http://www.cs.usu.edu/~jerry/ Utah State University