alsa-utils/alsactl/utils.c
Jaroslav Kysela 8403967669 alsactl: add locking for per-card initialization
Introduce the -K,--lock-dir parameter to specify the locking
directory. If the locking is active, files card<NUM>.lock
are used to serialize the multiple initialization requests
(udev, service).

Allow the relative -O,--lock-file argument (it's default now).

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2022-02-02 15:34:40 +01:00

335 lines
7.3 KiB
C

/*
* Advanced Linux Sound Architecture Control Program - Support routines
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
*
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <dirent.h>
#include <syslog.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <limits.h>
#include "alsactl.h"
int file_map(const char *filename, char **buf, size_t *bufsize)
{
struct stat stats;
int fd;
fd = open(filename, O_RDONLY);
if (fd < 0) {
return -1;
}
if (fstat(fd, &stats) < 0) {
close(fd);
return -1;
}
*buf = mmap(NULL, stats.st_size, PROT_READ, MAP_SHARED, fd, 0);
if (*buf == MAP_FAILED) {
close(fd);
return -1;
}
*bufsize = stats.st_size;
close(fd);
return 0;
}
void file_unmap(void *buf, size_t bufsize)
{
munmap(buf, bufsize);
}
size_t line_width(const char *buf, size_t bufsize, size_t pos)
{
int esc = 0;
size_t count;
for (count = pos; count < bufsize; count++) {
if (!esc && buf[count] == '\n')
break;
esc = buf[count] == '\\';
}
return count - pos;
}
void initfailed(int cardnumber, const char *reason, int exitcode)
{
int fp;
char *str;
char sexitcode[16];
if (statefile == NULL)
return;
if (snd_card_get_name(cardnumber, &str) < 0)
return;
sprintf(sexitcode, "%i", exitcode);
fp = open(statefile, O_WRONLY|O_CREAT|O_APPEND, 0644);
(void)write(fp, str, strlen(str));
(void)write(fp, ":", 1);
(void)write(fp, reason, strlen(reason));
(void)write(fp, ":", 1);
(void)write(fp, sexitcode, strlen(sexitcode));
(void)write(fp, "\n", 1);
close(fp);
free(str);
}
static void syslog_(int prio, const char *fcn, long line,
const char *fmt, va_list ap)
{
char buf[1024];
snprintf(buf, sizeof(buf), "%s: %s:%ld: ", command, fcn, line);
buf[sizeof(buf)-1] = '\0';
vsnprintf(buf + strlen(buf), sizeof(buf)-strlen(buf), fmt, ap);
buf[sizeof(buf)-1] = '\0';
syslog(prio, "%s", buf);
}
void info_(const char *fcn, long line, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
if (use_syslog) {
syslog_(LOG_INFO, fcn, line, fmt, ap);
} else {
fprintf(stdout, "%s: %s:%ld: ", command, fcn, line);
vfprintf(stdout, fmt, ap);
putc('\n', stdout);
}
va_end(ap);
}
void error_(const char *fcn, long line, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
if (use_syslog) {
syslog_(LOG_ERR, fcn, line, fmt, ap);
} else {
fprintf(stderr, "%s: %s:%ld: ", command, fcn, line);
vfprintf(stderr, fmt, ap);
putc('\n', stderr);
}
va_end(ap);
}
void cerror_(const char *fcn, long line, int cond, const char *fmt, ...)
{
va_list ap;
if (!cond && !debugflag)
return;
va_start(ap, fmt);
if (use_syslog) {
syslog_(LOG_ERR, fcn, line, fmt, ap);
} else {
fprintf(stderr, "%s: %s:%ld: ", command, fcn, line);
vfprintf(stderr, fmt, ap);
putc('\n', stderr);
}
va_end(ap);
}
void dbg_(const char *fcn, long line, const char *fmt, ...)
{
va_list ap;
if (!debugflag)
return;
va_start(ap, fmt);
if (use_syslog) {
syslog_(LOG_DEBUG, fcn, line, fmt, ap);
} else {
fprintf(stderr, "%s: %s:%ld: ", command, fcn, line);
vfprintf(stderr, fmt, ap);
putc('\n', stderr);
}
va_end(ap);
}
void error_handler(const char *file, int line, const char *function, int err, const char *fmt, ...)
{
char buf[2048];
va_list arg;
va_start(arg, fmt);
vsnprintf(buf, sizeof(buf), fmt, arg);
va_end(arg);
if (use_syslog)
syslog(LOG_ERR, "alsa-lib %s:%i:(%s) %s%s%s\n", file, line, function,
buf, err ? ": " : "", err ? snd_strerror(err) : "");
else
fprintf(stderr, "alsa-lib %s:%i:(%s) %s%s%s\n", file, line, function,
buf, err ? ": " : "", err ? snd_strerror(err) : "");
}
int load_configuration(const char *file, snd_config_t **top, int *open_failed)
{
snd_config_t *config;
snd_input_t *in;
int err, stdio_flag, lock_fd = -EINVAL;
*top = NULL;
if (open_failed)
*open_failed = 0;
err = snd_config_top(&config);
if (err < 0) {
error("snd_config_top error: %s", snd_strerror(err));
return err;
}
stdio_flag = !strcmp(file, "-");
if (stdio_flag) {
err = snd_input_stdio_attach(&in, stdin, 0);
} else {
lock_fd = state_lock(file, LOCK_TIMEOUT);
err = lock_fd >= 0 ? snd_input_stdio_open(&in, file, "r") : lock_fd;
}
if (err < 0) {
if (open_failed)
*open_failed = 1;
goto out;
}
err = snd_config_load(config, in);
snd_input_close(in);
if (err < 0) {
error("snd_config_load error: %s", snd_strerror(err));
out:
if (lock_fd >= 0)
state_unlock(lock_fd, file);
snd_config_delete(config);
snd_config_update_free_global();
return err;
} else {
if (lock_fd >= 0)
state_unlock(lock_fd, file);
*top = config;
return 0;
}
}
void snd_card_iterator_init(struct snd_card_iterator *iter, int cardno)
{
iter->card = cardno;
iter->single = cardno >= 0;
iter->first = true;
iter->name[0] = '\0';
}
int snd_card_iterator_sinit(struct snd_card_iterator *iter, const char *cardname)
{
int cardno = -1;
if (cardname) {
if (strncmp(cardname, "hw:", 3) == 0)
cardname += 3;
cardno = snd_card_get_index(cardname);
if (cardno < 0) {
error("Cannot find soundcard '%s'...", cardname);
return cardno;
}
}
snd_card_iterator_init(iter, cardno);
return 0;
}
const char *snd_card_iterator_next(struct snd_card_iterator *iter)
{
if (iter->single) {
if (iter->first) {
iter->first = false;
goto retval;
}
return NULL;
}
if (snd_card_next(&iter->card) < 0) {
if (!ignore_nocards && iter->first)
error("No soundcards found...");
return NULL;
}
iter->first = false;
if (iter->card < 0)
return NULL;
retval:
snprintf(iter->name, sizeof(iter->name), "hw:%d", iter->card);
return (const char *)iter->name;
}
int snd_card_iterator_error(struct snd_card_iterator *iter)
{
return iter->first ? (ignore_nocards ? 0 : -ENODEV) : 0;
}
static int cleanup_filename_filter(const struct dirent *dirent)
{
size_t flen;
if (dirent == NULL)
return 0;
if (dirent->d_type == DT_DIR)
return 0;
flen = strlen(dirent->d_name);
if (flen <= 5)
return 0;
if (strncmp(&dirent->d_name[flen-5], ".conf", 5) == 0)
return 1;
return 0;
}
int snd_card_clean_cfgdir(const char *cfgdir, int cardno)
{
char path[PATH_MAX];
struct dirent **list;
int lasterr = 0, n, j;
snprintf(path, sizeof(path), "%s/card%d.conf.d", cfgdir, cardno);
n = scandir(path, &list, cleanup_filename_filter, NULL);
if (n < 0) {
if (errno == ENOENT)
return 0;
return -errno;
}
for (j = 0; j < n; j++) {
snprintf(path, sizeof(path), "%s/card%d.conf.d/%s", cfgdir, cardno, list[j]->d_name);
if (remove(path)) {
error("Unable to remove file '%s'", path);
lasterr = -errno;
}
}
return lasterr;
}