From: Jaroslav Kysela <perex@perex.cz>
Date: Wed, 3 May 2023 09:42:35 +0000 (+0200)
Subject: pcm: add SND_PCM_EINTR open mode
X-Git-Tag: v1.2.9~5
X-Git-Url: https://git.alsa-project.org/?a=commitdiff_plain;h=d6d5982d3ae68b72a1a53420b77ac269ef93d40e;p=alsa-lib.git

pcm: add SND_PCM_EINTR open mode

Add possibility to return -EINTR instead waiting for the event. The
applications may want to handle -EINTR condition themselves.

BugLink: https://github.com/alsa-project/alsa-lib/issues/228
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
---

diff --git a/include/pcm.h b/include/pcm.h
index 25cd12d1..a29ea980 100644
--- a/include/pcm.h
+++ b/include/pcm.h
@@ -393,6 +393,8 @@ typedef long snd_pcm_sframes_t;
 #define SND_PCM_NONBLOCK		0x00000001
 /** Async notification (flag for open mode) \hideinitializer */
 #define SND_PCM_ASYNC			0x00000002
+/** Return EINTR instead blocking (wait operation) */
+#define SND_PCM_EINTR			0x00000080
 /** In an abort state (internal, not allowed for open) */
 #define SND_PCM_ABORT			0x00008000
 /** Disable automatic (but not forced!) rate resamplinig */
diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c
index 01c624d3..41a36b36 100644
--- a/src/pcm/pcm.c
+++ b/src/pcm/pcm.c
@@ -2938,7 +2938,7 @@ int snd_pcm_wait_nocheck(snd_pcm_t *pcm, int timeout)
 		err_poll = poll(pfd, npfds, timeout);
 		__snd_pcm_lock(pcm->fast_op_arg);
 		if (err_poll < 0) {
-		        if (errno == EINTR && !PCMINABORT(pcm))
+			if (errno == EINTR && !PCMINABORT(pcm) && !(pcm->mode & SND_PCM_EINTR))
 		                continue;
 			return -errno;
                 }