components/volume.c
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/* See LICENSE file for copyright and license details. */ #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <string.h> #if defined(__OpenBSD__) #include <soundcard.h> #else #include <sys/soundcard.h> #endif #include <sys/ioctl.h> #include <unistd.h> #include "../util.h" const char * vol_perc(const char *card) { size_t i; int v, afd, devmask; char *vnames[] = SOUND_DEVICE_NAMES; if ((afd = open(card, O_RDONLY | O_NONBLOCK)) < 0) { warn("open '%s':", card); return NULL; } if (ioctl(afd, (int)SOUND_MIXER_READ_DEVMASK, &devmask) < 0) { warn("ioctl 'SOUND_MIXER_READ_DEVMASK':"); close(afd); return NULL; } for (i = 0; i < LEN(vnames); i++) { if (devmask & (1 << i) && !strcmp("vol", vnames[i])) { if (ioctl(afd, MIXER_READ(i), &v) < 0) { warn("ioctl 'MIXER_READ(%ld)':", i); close(afd); return NULL; } } } close(afd); return bprintf("%d", v & 0xff); }