make alsamixer more responsive

2 files changed, 23 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 42b6414..c56ca40 100644
--- a/Makefile
+++ b/Makefile
@@ -21,7 +21,7 @@ all: $(libs) $(libsymlinks) $(pkgconfigs)
 %.pc: %.pc.in
 	m4 -DINCLUDEDIR="$(PREFIX)$(includedir)" -DLIBDIR="$(PREFIX)$(libdir)" $^ > $@
 
-libasound.so.2.0.0: private override CPPFLAGS += -D_POSIX_SOURCE
+libasound.so.2.0.0: private override CPPFLAGS += -D_DEFAULT_SOURCE
 libasound.so.2.0.0: private override CPPFLAGS += -DBYTE_ORDER=__BYTE_ORDER -DLITTLE_ENDIAN=__LITTLE_ENDIAN -DBIG_ENDIAN=__BIG_ENDIAN
 libasound.so.2.0.0: private override CFLAGS += -Wno-unused-parameter -Wno-deprecated-declarations
 libasound.so.2.0.0: private override LDFLAGS += -Wl,--version-script=libasound.map -Wl,-soname,libasound.so.2
diff --git a/src/mixer.c b/src/mixer.c
index 3213995..4738012 100644
--- a/src/mixer.c
+++ b/src/mixer.c
@@ -2,6 +2,7 @@
 #include <sndio.h>
 #include <stdbool.h>
 #include <stdio.h>
+#include <time.h>
 #include "util/sysex.h"
 #include "util/util.h"
 
@@ -15,6 +16,7 @@ struct _snd_mixer_elem {
 struct _snd_mixer {
    struct mio_hdl *hdl;
    snd_mixer_elem_t *controls;
+   uint64_t last_pollin_time;
 };
 
 #define MIXER_MAX_CHANNELS 16
@@ -219,13 +221,31 @@ snd_mixer_poll_descriptors(snd_mixer_t *mixer, struct pollfd *pfds, unsigned int
    return mio_pollfd(mixer->hdl, pfds, POLLOUT | POLLIN);
 }
 
+static uint64_t
+get_time_ns(void)
+{
+   struct timespec ts;
+   clock_gettime(CLOCK_MONOTONIC, &ts);
+   return (uint64_t)ts.tv_sec * (uint64_t)1e9 + (uint64_t)ts.tv_nsec;
+}
+
 int
 snd_mixer_poll_descriptors_revents(snd_mixer_t *mixer, struct pollfd *pfds, unsigned int nfds, unsigned short *revents)
 {
    if (!revents || nfds > (unsigned int)mio_nfds(mixer->hdl))
       return -1;
 
-   *revents = mio_revents(mixer->hdl, pfds) | POLLIN;
+   *revents = mio_revents(mixer->hdl, pfds);
+
+   const uint64_t time = get_time_ns();
+   if (!(*revents & POLLIN)) {
+      if (((time - mixer->last_pollin_time) / 1e6) > 20)
+         *revents |= POLLIN;
+   }
+
+   if (*revents & POLLIN)
+      mixer->last_pollin_time = time;
+
    return 0;
 }
 
@@ -291,6 +311,7 @@ int
 snd_mixer_selem_set_playback_dB(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value, int dir)
 {
    setvol(elem->mixer, elem->index, value + 0x7f);
+   elem->vol = value + 0x7f;
    return 0;
 }