freebsd-dev/usr.sbin/mixer/mixer.c
Mark Johnston 5c2b216a1c mixer: Fix default_unit switching with mixers that have no devices
Apparently it's possible for a mixer to have no devices:

$ mixer -f /dev/mixer2
pcm2:mixer: <USB audio> at ? kld snd_uaudio (rec)
$

If this is the default sound device, an attempt to change the default
unit using mixer -d fails with a segfault because mod_dunit is called
with a NULL device pointer, which is dereferenced to get the parent
mixer.

ctl_dunit seems to be a dummy, i.e., we don't actually need it and can
simply pass the mixer to mod_dunit() directly.  This patch removes that
structure and associated indirection to fix the crash.

Reviewed by:	christos, hselasky
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D38060
2023-01-16 08:02:54 -05:00

512 lines
11 KiB
C

/*-
* Copyright (c) 2021 Christos Margiolis <christos@FreeBSD.org>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* $FreeBSD$
*/
#include <err.h>
#include <errno.h>
#include <mixer.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
enum {
C_VOL = 0,
C_MUT,
C_SRC,
};
static void usage(void) __dead2;
static void initctls(struct mixer *);
static void printall(struct mixer *, int);
static void printminfo(struct mixer *, int);
static void printdev(struct mixer *, int);
static void printrecsrc(struct mixer *, int); /* XXX: change name */
static int set_dunit(struct mixer *, int);
/* Control handlers */
static int mod_volume(struct mix_dev *, void *);
static int mod_mute(struct mix_dev *, void *);
static int mod_recsrc(struct mix_dev *, void *);
static int print_volume(struct mix_dev *, void *);
static int print_mute(struct mix_dev *, void *);
static int print_recsrc(struct mix_dev *, void *);
int
main(int argc, char *argv[])
{
struct mixer *m;
mix_ctl_t *cp;
char *name = NULL, buf[NAME_MAX];
char *p, *q, *devstr, *ctlstr, *valstr = NULL;
int dunit, i, n, pall = 1, shorthand;
int aflag = 0, dflag = 0, oflag = 0, sflag = 0;
int ch;
while ((ch = getopt(argc, argv, "ad:f:hos")) != -1) {
switch (ch) {
case 'a':
aflag = 1;
break;
case 'd':
dunit = strtol(optarg, NULL, 10);
if (errno == EINVAL || errno == ERANGE)
err(1, "strtol");
dflag = 1;
break;
case 'f':
name = optarg;
break;
case 'o':
oflag = 1;
break;
case 's':
sflag = 1;
break;
case 'h': /* FALLTHROUGH */
case '?':
default:
usage();
}
}
argc -= optind;
argv += optind;
/* Print all mixers and exit. */
if (aflag) {
if ((n = mixer_get_nmixers()) < 0)
err(1, "mixer_get_nmixers");
for (i = 0; i < n; i++) {
(void)snprintf(buf, sizeof(buf), "/dev/mixer%d", i);
if ((m = mixer_open(buf)) == NULL)
err(1, "mixer_open: %s", buf);
initctls(m);
if (sflag)
printrecsrc(m, oflag);
else {
printall(m, oflag);
if (oflag)
printf("\n");
}
(void)mixer_close(m);
}
return (0);
}
if ((m = mixer_open(name)) == NULL)
err(1, "mixer_open: %s", name);
initctls(m);
if (dflag && set_dunit(m, dunit) < 0)
goto parse;
if (sflag) {
printrecsrc(m, oflag);
(void)mixer_close(m);
return (0);
}
parse:
while (argc > 0) {
if ((p = strdup(*argv)) == NULL)
err(1, "strdup(%s)", *argv);
/* Check if we're using the shorthand syntax for volume setting. */
shorthand = 0;
for (q = p; *q != '\0'; q++) {
if (*q == '=') {
q++;
shorthand = ((*q >= '0' && *q <= '9') ||
*q == '+' || *q == '-' || *q == '.');
break;
} else if (*q == '.')
break;
}
/* Split the string into device, control and value. */
devstr = strsep(&p, ".=");
if ((m->dev = mixer_get_dev_byname(m, devstr)) == NULL) {
warnx("%s: no such device", devstr);
goto next;
}
/* Input: `dev`. */
if (p == NULL) {
printdev(m, 1);
pall = 0;
goto next;
} else if (shorthand) {
/*
* Input: `dev=N` -> shorthand for `dev.volume=N`.
*
* We don't care what the rest of the string contains as
* long as we're sure the very beginning is right,
* mod_volume() will take care of parsing it properly.
*/
cp = mixer_get_ctl(m->dev, C_VOL);
cp->mod(cp->parent_dev, p);
goto next;
}
ctlstr = strsep(&p, "=");
if ((cp = mixer_get_ctl_byname(m->dev, ctlstr)) == NULL) {
warnx("%s.%s: no such control", devstr, ctlstr);
goto next;
}
/* Input: `dev.control`. */
if (p == NULL) {
(void)cp->print(cp->parent_dev, cp->name);
pall = 0;
goto next;
}
valstr = p;
/* Input: `dev.control=val`. */
cp->mod(cp->parent_dev, valstr);
next:
free(p);
argc--;
argv++;
}
if (pall)
printall(m, oflag);
(void)mixer_close(m);
return (0);
}
static void __dead2
usage(void)
{
fprintf(stderr, "usage: %1$s [-f device] [-d unit] [-os] [dev[.control[=value]]] ...\n"
" %1$s [-d unit] [-os] -a\n"
" %1$s -h\n", getprogname());
exit(1);
}
static void
initctls(struct mixer *m)
{
struct mix_dev *dp;
int rc = 0;
TAILQ_FOREACH(dp, &m->devs, devs) {
rc += mixer_add_ctl(dp, C_VOL, "volume", mod_volume, print_volume);
rc += mixer_add_ctl(dp, C_MUT, "mute", mod_mute, print_mute);
rc += mixer_add_ctl(dp, C_SRC, "recsrc", mod_recsrc, print_recsrc);
}
if (rc) {
(void)mixer_close(m);
err(1, "cannot make controls");
}
}
static void
printall(struct mixer *m, int oflag)
{
struct mix_dev *dp;
printminfo(m, oflag);
TAILQ_FOREACH(dp, &m->devs, devs) {
m->dev = dp;
printdev(m, oflag);
}
}
static void
printminfo(struct mixer *m, int oflag)
{
int playrec = MIX_MODE_PLAY | MIX_MODE_REC;
if (oflag)
return;
printf("%s:", m->mi.name);
if (*m->ci.longname != '\0')
printf(" <%s>", m->ci.longname);
if (*m->ci.hw_info != '\0')
printf(" %s", m->ci.hw_info);
if (m->mode != 0)
printf(" (");
if (m->mode & MIX_MODE_PLAY)
printf("play");
if ((m->mode & playrec) == playrec)
printf("/");
if (m->mode & MIX_MODE_REC)
printf("rec");
if (m->mode != 0)
printf(")");
if (m->f_default)
printf(" (default)");
printf("\n");
}
static void
printdev(struct mixer *m, int oflag)
{
struct mix_dev *d = m->dev;
mix_ctl_t *cp;
if (!oflag) {
printf(" %-10s= %.2f:%.2f ",
d->name, d->vol.left, d->vol.right);
if (!MIX_ISREC(m, d->devno))
printf(" pbk");
if (MIX_ISREC(m, d->devno))
printf(" rec");
if (MIX_ISRECSRC(m, d->devno))
printf(" src");
if (MIX_ISMUTE(m, d->devno))
printf(" mute");
printf("\n");
} else {
TAILQ_FOREACH(cp, &d->ctls, ctls) {
(void)cp->print(cp->parent_dev, cp->name);
}
}
}
static void
printrecsrc(struct mixer *m, int oflag)
{
struct mix_dev *dp;
int n = 0;
if (!m->recmask)
return;
if (!oflag)
printf("%s: ", m->mi.name);
TAILQ_FOREACH(dp, &m->devs, devs) {
if (MIX_ISRECSRC(m, dp->devno)) {
if (n++ && !oflag)
printf(", ");
printf("%s", dp->name);
if (oflag)
printf(".%s=+%s",
mixer_get_ctl(dp, C_SRC)->name, n ? " " : "");
}
}
printf("\n");
}
static int
set_dunit(struct mixer *m, int dunit)
{
int n;
if ((n = mixer_get_dunit()) < 0) {
warn("cannot get default unit");
return (-1);
}
if (mixer_set_dunit(m, dunit) < 0) {
warn("cannot set default unit to: %d", dunit);
return (-1);
}
printf("default_unit: %d -> %d\n", n, dunit);
return (0);
}
static int
mod_volume(struct mix_dev *d, void *p)
{
struct mixer *m;
mix_ctl_t *cp;
mix_volume_t v;
const char *val;
char *endp, lstr[8], rstr[8];
float lprev, rprev, lrel, rrel;
int n;
m = d->parent_mixer;
cp = mixer_get_ctl(m->dev, C_VOL);
val = p;
n = sscanf(val, "%7[^:]:%7s", lstr, rstr);
if (n == EOF) {
warnx("invalid volume value: %s", val);
return (-1);
}
lrel = rrel = 0;
if (n > 0) {
if (*lstr == '+' || *lstr == '-')
lrel = 1;
v.left = strtof(lstr, &endp);
if (*endp != '\0' && (*endp != '%' || *(endp + 1) != '\0')) {
warnx("invalid volume value: %s", lstr);
return (-1);
}
if (*endp == '%')
v.left /= 100.0f;
}
if (n > 1) {
if (*rstr == '+' || *rstr == '-')
rrel = 1;
v.right = strtof(rstr, &endp);
if (*endp != '\0' && (*endp != '%' || *(endp + 1) != '\0')) {
warnx("invalid volume value: %s", rstr);
return (-1);
}
if (*endp == '%')
v.right /= 100.0f;
}
switch (n) {
case 1:
v.right = v.left; /* FALLTHROUGH */
rrel = lrel;
case 2:
if (lrel)
v.left += m->dev->vol.left;
if (rrel)
v.right += m->dev->vol.right;
if (v.left < MIX_VOLMIN)
v.left = MIX_VOLMIN;
else if (v.left > MIX_VOLMAX)
v.left = MIX_VOLMAX;
if (v.right < MIX_VOLMIN)
v.right = MIX_VOLMIN;
else if (v.right > MIX_VOLMAX)
v.right = MIX_VOLMAX;
lprev = m->dev->vol.left;
rprev = m->dev->vol.right;
if (mixer_set_vol(m, v) < 0)
warn("%s.%s=%.2f:%.2f",
m->dev->name, cp->name, v.left, v.right);
else
printf("%s.%s: %.2f:%.2f -> %.2f:%.2f\n",
m->dev->name, cp->name, lprev, rprev, v.left, v.right);
}
return (0);
}
static int
mod_mute(struct mix_dev *d, void *p)
{
struct mixer *m;
mix_ctl_t *cp;
const char *val;
int n, opt = -1;
m = d->parent_mixer;
cp = mixer_get_ctl(m->dev, C_MUT);
val = p;
switch (*val) {
case '0':
opt = MIX_UNMUTE;
break;
case '1':
opt = MIX_MUTE;
break;
case '^':
opt = MIX_TOGGLEMUTE;
break;
default:
warnx("%c: no such modifier", *val);
return (-1);
}
n = MIX_ISMUTE(m, m->dev->devno);
if (mixer_set_mute(m, opt) < 0)
warn("%s.%s=%c", m->dev->name, cp->name, *val);
else
printf("%s.%s: %d -> %d\n",
m->dev->name, cp->name, n, MIX_ISMUTE(m, m->dev->devno));
return (0);
}
static int
mod_recsrc(struct mix_dev *d, void *p)
{
struct mixer *m;
mix_ctl_t *cp;
const char *val;
int n, opt = -1;
m = d->parent_mixer;
cp = mixer_get_ctl(m->dev, C_SRC);
val = p;
switch (*val) {
case '+':
opt = MIX_ADDRECSRC;
break;
case '-':
opt = MIX_REMOVERECSRC;
break;
case '=':
opt = MIX_SETRECSRC;
break;
case '^':
opt = MIX_TOGGLERECSRC;
break;
default:
warnx("%c: no such modifier", *val);
return (-1);
}
n = MIX_ISRECSRC(m, m->dev->devno);
if (mixer_mod_recsrc(m, opt) < 0)
warn("%s.%s=%c", m->dev->name, cp->name, *val);
else
printf("%s.%s: %d -> %d\n",
m->dev->name, cp->name, n, MIX_ISRECSRC(m, m->dev->devno));
return (0);
}
static int
print_volume(struct mix_dev *d, void *p)
{
struct mixer *m = d->parent_mixer;
const char *ctl_name = p;
printf("%s.%s=%.2f:%.2f\n",
m->dev->name, ctl_name, m->dev->vol.left, m->dev->vol.right);
return (0);
}
static int
print_mute(struct mix_dev *d, void *p)
{
struct mixer *m = d->parent_mixer;
const char *ctl_name = p;
printf("%s.%s=%d\n", m->dev->name, ctl_name, MIX_ISMUTE(m, m->dev->devno));
return (0);
}
static int
print_recsrc(struct mix_dev *d, void *p)
{
struct mixer *m = d->parent_mixer;
const char *ctl_name = p;
if (!MIX_ISRECSRC(m, m->dev->devno))
return (-1);
printf("%s.%s=+\n", m->dev->name, ctl_name);
return (0);
}