2 * This file is part of DisOrder
3 * Copyright (C) 2007 Richard Kettlewell
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
20 /** @file server/normalize.c
21 * @brief Convert "raw" format output to the configured format
23 * Currently we invoke sox even for trivial conversions such as byte-swapping.
24 * Ideally we would do all conversion including resampling in this one process
25 * and eliminate the dependency on sox.
36 #include <sys/types.h>
41 #include "configuration.h"
42 #include "speaker-protocol.h"
44 /** @brief Copy bytes from one file descriptor to another
45 * @param infd File descriptor read from
46 * @param outfd File descriptor to write to
47 * @param n Number of bytes to copy
49 static void copy(int infd, int outfd, size_t n) {
54 const ssize_t readden = read(infd, buffer,
55 n > sizeof buffer ? sizeof buffer : n);
60 fatal(errno, "read error");
63 fatal(0, "unexpected EOF");
66 while(written < readden) {
67 const ssize_t w = write(outfd, buffer + written, readden - written);
69 fatal(errno, "write error");
75 static void soxargs(const char ***pp, char **qq,
76 const struct stream_header *header) {
79 *qq += sprintf((char *)(*(*pp)++ = *qq), "-r%d", header->rate) + 1;
80 *qq += sprintf((char *)(*(*pp)++ = *qq), "-c%d", header->channels) + 1;
81 /* sox 12.17.9 insists on -b etc; CVS sox insists on -<n> etc; both are
83 switch(config->sox_generation) {
86 && header->endian != ENDIAN_NATIVE)
88 switch(header->bits) {
89 case 8: *(*pp)++ = "-b"; break;
90 case 16: *(*pp)++ = "-w"; break;
91 case 32: *(*pp)++ = "-l"; break;
92 case 64: *(*pp)++ = "-d"; break;
93 default: fatal(0, "cannot handle sample size %d", header->bits);
98 && header->endian != ENDIAN_NATIVE)
99 switch(header->endian) {
100 case ENDIAN_BIG: *(*pp)++ = "-B"; break;
101 case ENDIAN_LITTLE: *(*pp)++ = "-L"; break;
104 fatal(0, "cannot handle sample size %d", header->bits);
105 *qq += sprintf((char *)(*(*pp)++ = *qq), "-%d", header->bits / 8) + 1;
108 fatal(0, "unknown sox_generation %ld", config->sox_generation);
112 int main(int argc, char attribute((unused)) **argv) {
113 struct stream_header header, latest_format;
114 int n, p[2], outfd = -1;
118 if(!setlocale(LC_CTYPE, ""))
119 fatal(errno, "error calling setlocale");
121 fatal(0, "not intended to be invoked by users");
123 fatal(0, "cannot read configuration");
125 openlog(progname, LOG_PID, LOG_DAEMON);
126 log_default = &log_syslog;
128 memset(&latest_format, 0, sizeof latest_format);
131 while((size_t)n < sizeof header) {
132 int r = read(0, (char *)&header + n, sizeof header - n);
136 fatal(errno, "error reading header");
139 fatal(0, "EOF reading header");
146 /* Sanity check the header */
147 if(header.rate < 100 || header.rate > 1000000)
148 fatal(0, "implausible rate %"PRId32"Hz (%#"PRIx32")",
149 header.rate, header.rate);
150 if(header.channels < 1 || header.channels > 2)
151 fatal(0, "unsupported channel count %d", header.channels);
152 if(header.bits % 8 || !header.bits || header.bits > 64)
153 fatal(0, "unsupported sample size %d bits", header.bits);
154 if(header.endian != ENDIAN_BIG && header.endian != ENDIAN_LITTLE)
155 fatal(0, "unsupported byte order %x", header.bits);
156 /* Skip empty chunks regardless of their alleged format */
157 if(header.nbytes == 0)
159 /* If the format has changed we stop/start the converter */
160 if(!formats_equal(&header, &latest_format)) {
162 /* There's a running converter, stop it */
164 if(waitpid(pid, &n, 0) < 0)
165 fatal(errno, "error calling waitpid");
167 fatal(0, "sox failed: %#x", n);
171 if(!formats_equal(&header, &config->sample_format)) {
172 const char *av[32], **pp = av;
173 char argbuf[1024], *q = argbuf;
175 /* Input format doesn't match target, need to start a converter */
177 soxargs(&pp, &q, &header);
178 *pp++ = "-"; /* stdin */
179 soxargs(&pp, &q, &config->sample_format);
180 *pp++ = "-"; /* stdout */
182 /* This pipe will be sox's stdin */
184 if(!(pid = xfork())) {
189 execvp(av[0], (char **)av);
195 /* Input format matches output, can just copy bytes */
197 /* Remember current format for next iteration */
198 latest_format = header;
200 /* Convert or copy this chunk */
201 copy(0, outfd, header.nbytes);