mirror of
https://github.com/alsa-project/alsa-utils
synced 2024-11-14 06:05:43 +01:00
b402cf543a
See 'man 7 alsactl_init' for more details. Signed-off-by: Jaroslav Kysela <perex@perex.cz>
247 lines
6.3 KiB
C
247 lines
6.3 KiB
C
/*
|
|
* Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
|
|
*
|
|
* This program 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 version 2 of the License.
|
|
*
|
|
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*
|
|
*/
|
|
|
|
#define MY_MAX(a,b) ((a) > (b) ? (a) : (b))
|
|
|
|
#define READ_END 0
|
|
#define WRITE_END 1
|
|
|
|
static
|
|
int run_program1(struct space *space,
|
|
const char *command0, char *result,
|
|
size_t ressize, size_t *reslen, int log);
|
|
|
|
static
|
|
int run_program0(struct space *space,
|
|
const char *command0, char *result,
|
|
size_t ressize, size_t *reslen, int log)
|
|
{
|
|
int retval = 0;
|
|
int status;
|
|
int outpipe[2] = {-1, -1};
|
|
int errpipe[2] = {-1, -1};
|
|
pid_t pid;
|
|
char arg[PATH_SIZE];
|
|
char program[PATH_SIZE];
|
|
char *argv[(sizeof(arg) / 2) + 1];
|
|
int devnull;
|
|
int i;
|
|
|
|
/* build argv from comand */
|
|
strlcpy(arg, command0, sizeof(arg));
|
|
i = 0;
|
|
if (strchr(arg, ' ') != NULL) {
|
|
char *pos = arg;
|
|
|
|
while (pos != NULL) {
|
|
if (pos[0] == '\'') {
|
|
/* don't separate if in apostrophes */
|
|
pos++;
|
|
argv[i] = strsep(&pos, "\'");
|
|
while (pos != NULL && pos[0] == ' ')
|
|
pos++;
|
|
} else {
|
|
argv[i] = strsep(&pos, " ");
|
|
}
|
|
dbg("arg[%i] '%s'", i, argv[i]);
|
|
i++;
|
|
}
|
|
argv[i] = NULL;
|
|
} else {
|
|
argv[0] = arg;
|
|
argv[1] = NULL;
|
|
}
|
|
info("'%s'", command0);
|
|
|
|
/* prepare pipes from child to parent */
|
|
if (result || log) {
|
|
if (pipe(outpipe) != 0) {
|
|
Perror(space, "pipe failed: %s", strerror(errno));
|
|
return -1;
|
|
}
|
|
}
|
|
if (log) {
|
|
if (pipe(errpipe) != 0) {
|
|
Perror(space, "pipe failed: %s", strerror(errno));
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* allow programs in /lib/alsa called without the path */
|
|
if (strchr(argv[0], '/') == NULL) {
|
|
strlcpy(program, "/lib/alsa/", sizeof(program));
|
|
strlcat(program, argv[0], sizeof(program));
|
|
argv[0] = program;
|
|
}
|
|
|
|
pid = fork();
|
|
switch(pid) {
|
|
case 0:
|
|
/* child closes parent ends of pipes */
|
|
if (outpipe[READ_END] > 0)
|
|
close(outpipe[READ_END]);
|
|
if (errpipe[READ_END] > 0)
|
|
close(errpipe[READ_END]);
|
|
|
|
/* discard child output or connect to pipe */
|
|
devnull = open("/dev/null", O_RDWR);
|
|
if (devnull > 0) {
|
|
dup2(devnull, STDIN_FILENO);
|
|
if (outpipe[WRITE_END] < 0)
|
|
dup2(devnull, STDOUT_FILENO);
|
|
if (errpipe[WRITE_END] < 0)
|
|
dup2(devnull, STDERR_FILENO);
|
|
close(devnull);
|
|
} else
|
|
Perror(space, "open /dev/null failed: %s", strerror(errno));
|
|
if (outpipe[WRITE_END] > 0) {
|
|
dup2(outpipe[WRITE_END], STDOUT_FILENO);
|
|
close(outpipe[WRITE_END]);
|
|
}
|
|
if (errpipe[WRITE_END] > 0) {
|
|
dup2(errpipe[WRITE_END], STDERR_FILENO);
|
|
close(errpipe[WRITE_END]);
|
|
}
|
|
execv(argv[0], argv);
|
|
|
|
/* we should never reach this */
|
|
Perror(space, "exec of program '%s' failed", argv[0]);
|
|
_exit(1);
|
|
case -1:
|
|
Perror(space, "fork of '%s' failed: %s", argv[0], strerror(errno));
|
|
return -1;
|
|
default:
|
|
/* read from child if requested */
|
|
if (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
|
|
ssize_t count;
|
|
size_t respos = 0;
|
|
|
|
/* parent closes child ends of pipes */
|
|
if (outpipe[WRITE_END] > 0)
|
|
close(outpipe[WRITE_END]);
|
|
if (errpipe[WRITE_END] > 0)
|
|
close(errpipe[WRITE_END]);
|
|
|
|
/* read child output */
|
|
while (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
|
|
int fdcount;
|
|
fd_set readfds;
|
|
|
|
FD_ZERO(&readfds);
|
|
if (outpipe[READ_END] > 0)
|
|
FD_SET(outpipe[READ_END], &readfds);
|
|
if (errpipe[READ_END] > 0)
|
|
FD_SET(errpipe[READ_END], &readfds);
|
|
fdcount = select(MY_MAX(outpipe[READ_END], errpipe[READ_END])+1, &readfds, NULL, NULL, NULL);
|
|
if (fdcount < 0) {
|
|
if (errno == EINTR)
|
|
continue;
|
|
retval = -1;
|
|
break;
|
|
}
|
|
|
|
/* get stdout */
|
|
if (outpipe[READ_END] > 0 && FD_ISSET(outpipe[READ_END], &readfds)) {
|
|
char inbuf[1024];
|
|
char *pos;
|
|
char *line;
|
|
|
|
count = read(outpipe[READ_END], inbuf, sizeof(inbuf)-1);
|
|
if (count <= 0) {
|
|
close(outpipe[READ_END]);
|
|
outpipe[READ_END] = -1;
|
|
if (count < 0) {
|
|
Perror(space, "stdin read failed: %s", strerror(errno));
|
|
retval = -1;
|
|
}
|
|
continue;
|
|
}
|
|
inbuf[count] = '\0';
|
|
|
|
/* store result for rule processing */
|
|
if (result) {
|
|
if (respos + count < ressize) {
|
|
memcpy(&result[respos], inbuf, count);
|
|
respos += count;
|
|
} else {
|
|
Perror(space, "ressize %ld too short", (long)ressize);
|
|
retval = -1;
|
|
}
|
|
}
|
|
pos = inbuf;
|
|
while ((line = strsep(&pos, "\n")))
|
|
if (pos || line[0] != '\0')
|
|
info("'%s' (stdout) '%s'", argv[0], line);
|
|
}
|
|
|
|
/* get stderr */
|
|
if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) {
|
|
char errbuf[1024];
|
|
char *pos;
|
|
char *line;
|
|
|
|
count = read(errpipe[READ_END], errbuf, sizeof(errbuf)-1);
|
|
if (count <= 0) {
|
|
close(errpipe[READ_END]);
|
|
errpipe[READ_END] = -1;
|
|
if (count < 0)
|
|
Perror(space, "stderr read failed: %s", strerror(errno));
|
|
continue;
|
|
}
|
|
errbuf[count] = '\0';
|
|
pos = errbuf;
|
|
while ((line = strsep(&pos, "\n")))
|
|
if (pos || line[0] != '\0')
|
|
info("'%s' (stderr) '%s'", argv[0], line);
|
|
}
|
|
}
|
|
if (outpipe[READ_END] > 0)
|
|
close(outpipe[READ_END]);
|
|
if (errpipe[READ_END] > 0)
|
|
close(errpipe[READ_END]);
|
|
|
|
/* return the childs stdout string */
|
|
if (result) {
|
|
result[respos] = '\0';
|
|
dbg("result='%s'", result);
|
|
if (reslen)
|
|
*reslen = respos;
|
|
}
|
|
}
|
|
waitpid(pid, &status, 0);
|
|
if (WIFEXITED(status)) {
|
|
info("'%s' returned with status %i", argv[0], WEXITSTATUS(status));
|
|
if (WEXITSTATUS(status) != 0)
|
|
retval = -1;
|
|
} else {
|
|
Perror(space, "'%s' abnormal exit", argv[0]);
|
|
retval = -1;
|
|
}
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
static
|
|
int run_program(struct space *space, const char *command0, char *result,
|
|
size_t ressize, size_t *reslen, int log)
|
|
{
|
|
if (command0[0] == '_' && command0[1] == '_')
|
|
return run_program1(space, command0, result, ressize, reslen, log);
|
|
return run_program0(space, command0, result, ressize, reslen, log);
|
|
}
|