refactor vol_perc to not depend on alsa libraries

README.md

@@ -23,7 +23,7 @@ The following information is included:
 - Swap status (free swap, percentage, total swap and used swap)
 - Temperature
 - Uptime
-- Volume percentage (ALSA)
+- Volume percentage (OSS/ALSA)
 - WiFi signal percentage and ESSID
 
 Multiple entries per function (e.g. multiple batteries) are supported and everything can be reordered and customized via a C header file (similar to other suckless programs).

config.def.h

@@ -34,7 +34,7 @@
 - uid (uid of current user) [argument: NULL]
 - uptime (uptime) [argument: NULL]
 - username (username of current user) [argument: NULL]
-- vol_perc (alsa volume and mute status in percent) [argument: soundcard]
+- vol_perc (oss/alsa volume and mute status in percent) [argument: /dev/mixer]
 - wifi_perc (wifi signal in percent) [argument: wifi card interface name]
 - wifi_essid (wifi essid) [argument: wifi card interface name] */
 static const struct arg args[] = {

config.mk

@@ -9,7 +9,7 @@ X11INC = /usr/X11R6/include
 X11LIB = /usr/X11R6/lib
 
 INCS = -I. -I/usr/include -I${X11INC}
-LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 -lasound
+LIBS = -L/usr/lib -lc -L${X11LIB} -lX11
 
 CPPFLAGS = -DVERSION=\"${VERSION}\" -D_GNU_SOURCE
 # -Wno-unused-function for routines not activated by user

slstatus.c

@@ -1,6 +1,5 @@
 /* See LICENSE file for copyright and license details. */
 
-#include <alsa/asoundlib.h>
 #include <err.h>
 #include <fcntl.h>
 #include <ifaddrs.h>
@@ -18,6 +17,7 @@
 #include <sys/stat.h>
 #include <sys/statvfs.h>
 #include <sys/socket.h>
+#include <sys/soundcard.h>
 #include <sys/sysinfo.h>
 #include <sys/types.h>
 #include <sys/utsname.h>
@@ -617,41 +617,26 @@ uid(void)
 static char *
 vol_perc(const char *card)
 {
-	int mute;
-	long int vol, max, min;
-	snd_mixer_t *handle;
-	snd_mixer_elem_t *elem;
-	snd_mixer_selem_id_t *s_elem;
+	unsigned int i;
+	int v, afd, devmask;
+	char *vnames[] = SOUND_DEVICE_NAMES;
 
-	snd_mixer_open(&handle, 0);
-	snd_mixer_attach(handle, card);
-	snd_mixer_selem_register(handle, NULL, NULL);
-	snd_mixer_load(handle);
-	snd_mixer_selem_id_malloc(&s_elem);
-	snd_mixer_selem_id_set_name(s_elem, "Master");
-	elem = snd_mixer_find_selem(handle, s_elem);
-
-	if (elem == NULL) {
-		snd_mixer_selem_id_free(s_elem);
-		snd_mixer_close(handle);
-		warn("Failed to get volume percentage for %s", card);
+	afd = open(card, O_RDONLY);
+	if (afd < 0) {
+		warn("Cannot open %s", card);
 		return smprintf(UNKNOWN_STR);
 	}
 
-	snd_mixer_handle_events(handle);
-	snd_mixer_selem_get_playback_volume_range(elem, &min, &max);
-	snd_mixer_selem_get_playback_volume(elem, 0, &vol);
-	snd_mixer_selem_get_playback_switch(elem, 0, &mute);
+	ioctl(afd, MIXER_READ(SOUND_MIXER_DEVMASK), &devmask);
+	for (i = 0; i < (sizeof(vnames) / sizeof((vnames[0]))); i++)
+		if (devmask & (1 << i))
+			if (!strcmp("vol", vnames[i]))
+				ioctl(afd, MIXER_READ(i), &v);
 
-	snd_mixer_selem_id_free(s_elem);
-	snd_mixer_close(handle);
-
-	if (!mute)
+	close(afd);
+	if (v == 0)
 		return smprintf("mute");
-	else if (max == 0)
-		return smprintf("0%%");
-	else
-		return smprintf("%lu%%", ((uint_fast16_t)(vol * 100) / max));
+	return smprintf("%d%%", v & 0xff);
 }
 
 static char *