[alsa-devel] [RFCv2][PATCH 26/38] axfer: add an option to suppress event waiting

[Takashi Sakamoto]

In aplay, '--test-nowait' is used to suppress calls of snd_pcm_wait()
when I/O operations return -EAGAIN or process truncated number of data
frames. This seems to be for debugging purpose. In this program, this
option is equivalent to suppress event waiting.

This commit adds support for this option.

Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 axfer/options.c                 | 13 +++++++++++++
 axfer/options.h                 |  1 +
 axfer/xfer-libasound-irq-mmap.c |  8 +++++---
 axfer/xfer-libasound-irq-rw.c   | 16 ++++++++++------
 axfer/xfer-libasound.c          |  2 +-
 5 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/axfer/options.c b/axfer/options.c
index 1433e458..5dfbffac 100644
--- a/axfer/options.c
+++ b/axfer/options.c
@@ -16,6 +16,7 @@ enum no_short_opts {
 	/* 128 belongs to non us-ascii character set. */
 	OPT_DUMP_HW_PARAMS = 128,
 	OPT_FATAL_ERRORS,
+	OPT_TEST_NOWAIT,
 	/* Obsoleted. */
 	OPT_MAX_FILE_TIME,
 };
@@ -272,6 +273,15 @@ static int apply_policies(struct context_options *opts,
 		return -EINVAL;
 	}
 
+	if (opts->test_nowait) {
+		if (!opts->nonblock && !opts->mmap) {
+			fprintf(stderr,
+				"An option for nowait test should be used with "
+				"nonblock or mmap options.\n");
+			return -EINVAL;
+		}
+	}
+
 	return 0;
 }
 
@@ -318,6 +328,7 @@ int context_options_init(struct context_options *opts, int argc,
 		/* For debugging. */
 		{"dump-hw-params",	0, 0, OPT_DUMP_HW_PARAMS},
 		{"fatal-errors",	0, 0, OPT_FATAL_ERRORS},
+		{"test-nowait",		0, 0, OPT_TEST_NOWAIT},
 		/* Obsoleted. */
 		{"max-file-time",       1, 0, OPT_MAX_FILE_TIME},
 		{NULL,			0, 0, 0},
@@ -365,6 +376,8 @@ int context_options_init(struct context_options *opts, int argc,
 			opts->dump_hw_params = true;
 		else if (c == OPT_FATAL_ERRORS)
 			opts->finish_at_xrun = true;
+		else if (c == OPT_TEST_NOWAIT)
+			opts->test_nowait = true;
 		else if (c == OPT_MAX_FILE_TIME) {
 			fprintf(stderr,
 				"An option '--%s' is obsoleted and has no "
diff --git a/axfer/options.h b/axfer/options.h
index 272ce9b9..3052d01a 100644
--- a/axfer/options.h
+++ b/axfer/options.h
@@ -39,6 +39,7 @@ struct context_options {
 	/* For debugging. */
 	bool dump_hw_params;
 	bool finish_at_xrun;
+	bool test_nowait;
 };
 
 int context_options_init(struct context_options *opts, int argc,
diff --git a/axfer/xfer-libasound-irq-mmap.c b/axfer/xfer-libasound-irq-mmap.c
index b2fb9a58..a892642f 100644
--- a/axfer/xfer-libasound-irq-mmap.c
+++ b/axfer/xfer-libasound-irq-mmap.c
@@ -75,9 +75,11 @@ static int irq_mmap_process_frames(struct libasound_state *state,
 	snd_pcm_sframes_t consumed_count;
 	int err;
 
-	err = waiter_context_wait_event(state->waiter, -1);
-	if (err < 0)
-		goto error;
+	if (state->waiter) {
+		err = waiter_context_wait_event(state->waiter, -1);
+		if (err < 0)
+			goto error;
+	}
 
 	avail = *frame_count;
 	err = snd_pcm_mmap_begin(state->handle, &areas, &frame_offset, &avail);
diff --git a/axfer/xfer-libasound-irq-rw.c b/axfer/xfer-libasound-irq-rw.c
index 592bc0c4..26db75d6 100644
--- a/axfer/xfer-libasound-irq-rw.c
+++ b/axfer/xfer-libasound-irq-rw.c
@@ -185,9 +185,11 @@ static int r_process_frames_nonblocking(struct libasound_state *state,
 			goto error;
 	}
 
-	err = waiter_context_wait_event(state->waiter, -1);
-	if (err < 0)
-		goto error;
+	if (state->waiter) {
+		err = waiter_context_wait_event(state->waiter, -1);
+		if (err < 0)
+			goto error;
+	}
 
 	/* Check available space on the buffer. */
 	avail = snd_pcm_avail(state->handle);
@@ -340,9 +342,11 @@ static int w_process_frames_nonblocking(struct libasound_state *state,
 	unsigned int avail_count;
 	int err;
 
-	err = waiter_context_wait_event(state->waiter, -1);
-	if (err < 0)
-		goto error;
+	if (state->waiter) {
+		err = waiter_context_wait_event(state->waiter, -1);
+		if (err < 0)
+			goto error;
+	}
 
 	/* Check available space on the buffer. */
 	avail = snd_pcm_avail(state->handle);
diff --git a/axfer/xfer-libasound.c b/axfer/xfer-libasound.c
index 0bc4f93e..4bf5b58b 100644
--- a/axfer/xfer-libasound.c
+++ b/axfer/xfer-libasound.c
@@ -76,7 +76,7 @@ static int xfer_libasound_init(struct xfer_context *xfer,
 	}
 
 	state->nonblock = !!(mode & SND_PCM_NONBLOCK);
-	if (opts->nonblock || opts->mmap) {
+	if ((opts->nonblock || opts->mmap) && !opts->test_nowait) {
 		state->waiter = malloc(sizeof(*state->waiter));
 		if (state->waiter == NULL)
 			return -ENOMEM;
-- 
2.11.0