提交: ce9a1b1c6983dbb91c592643d1d90d64786bbcbe - hardware-libaudio (git)

hardware/libaudio

Commit MetaInfo

• 修订版: ce9a1b1c6983dbb91c592643d1d90d64786bbcbe (tree)
• 时间: 2017-05-02 18:43:41
• 作者: Valentin Manea <valy@mrs....>
• Commiter: Chih-Wei Huang

Log Message

select_card: only open PCM devices with the same type as requested

Let select_card() only open /dev/snd/pcmCxp for playback and /dev/snd/pcmCxc
for capture device. This way select_card won't try to open a device twice.

In some cases the second query on a playback device(even though
select_card is searching for a capture device) will block inside the
kernel causing audio to stop working.

更改概述

• modified: audio_hw.c

差异

--- a/audio_hw.c
+++ b/audio_hw.c
@@ -183,6 +183,7 @@ struct snd_pcm_info *select_card(unsigned int device, unsigned int flags)
     static struct snd_pcm_info *cached_info[4];
     struct snd_pcm_info *info;
     int d = !!(flags & PCM_IN);
+    char e = d ? 'c' : 'p';
     if (!cached_info[d] && !cached_info[d + 2]) {
         struct dirent **namelist;
         char path[PATH_MAX] = "/dev/snd/";
@@ -191,7 +192,7 @@ struct snd_pcm_info *select_card(unsigned int device, unsigned int flags)
             int i, fd;
             for (i = 0; i < n; i++) {
                 struct dirent *de = namelist[i];
-                if (!strncmp(de->d_name, "pcmC", 4)) {
+                if (!strncmp(de->d_name, "pcmC", 4) && de->d_name[strlen(de->d_name) - 1] == e) {
                     strcpy(path + 9, de->d_name);
                     if ((fd = open(path, O_RDWR)) >= 0) {
                         info = malloc(sizeof(*info));