faa52bdcc0
Make use of strerror(errno) and format all errors equally: function ['parameters']: error message
45 lines
997 B
C
45 lines
997 B
C
/* See LICENSE file for copyright and license details. */
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#if defined(__linux__)
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#include <errno.h>
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#include <fcntl.h>
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#include <sys/soundcard.h>
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#include <sys/ioctl.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include "../util.h"
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const char *
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vol_perc(const char *card)
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{
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unsigned int i;
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int v, afd, devmask;
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char *vnames[] = SOUND_DEVICE_NAMES;
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afd = open(card, O_RDONLY | O_NONBLOCK);
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if (afd == -1) {
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fprintf(stderr, "open '%s': %s\n", card, strerror(errno));
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return NULL;
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}
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if (ioctl(afd, SOUND_MIXER_READ_DEVMASK, &devmask) == -1) {
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fprintf(stderr, "ioctl 'SOUND_MIXER_READ_DEVMASK': %s\n", strerror(errno));
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close(afd);
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return NULL;
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}
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for (i = 0; i < LEN(vnames); i++) {
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if (devmask & (1 << i) && !strcmp("vol", vnames[i])) {
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if (ioctl(afd, MIXER_READ(i), &v) == -1) {
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fprintf(stderr, "ioctl 'MIXER_READ(%d)': %s\n", i, strerror(errno));
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close(afd);
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return NULL;
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}
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}
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}
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close(afd);
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return bprintf("%d", v & 0xff);
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}
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#endif
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