From 37b778278efb49e0254868d1ddddbdac0bf43890 Mon Sep 17 00:00:00 2001
From: Martin Piatka <piatka@cesnet.cz>
Date: Thu, 29 Jun 2023 14:10:47 +0200
Subject: [PATCH] acap/pipewire: Set frame format in on_param_changed callback

Since pipewire will convert the audio format to anything we ask it to,
this shouldn't have any effect. Maybe will help when implementing the
exclusive device mode in the future.
---
 src/audio/capture/pipewire.cpp | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/audio/capture/pipewire.cpp b/src/audio/capture/pipewire.cpp
index 977eda3cf..45bf084f2 100644
--- a/src/audio/capture/pipewire.cpp
+++ b/src/audio/capture/pipewire.cpp
@@ -122,14 +122,24 @@ static void on_param_changed(void *state, uint32_t id, const struct spa_pod *par
                         audio_params.info.raw.rate,
                         audio_params.info.raw.channels);
 
-        assert(audio_params.info.raw.rate == (unsigned) s->sample_rate);
-        assert(audio_params.info.raw.channels == (unsigned) s->ch_count);
-        assert(audio_params.info.raw.format == get_pw_format_from_bps(s->bps));
+
+        /* It is not expected that params change while the stream is active,
+         * therefore this should run only during during init (we wait for stream to
+         * change into the streaming state there).  As a result, we probably don't
+         * need any extra synchronization between this and
+         * audio_cap_pipewire_read().
+         */
+        s->frame.ch_count = audio_params.info.raw.channels;
+        s->frame.bps = get_bps_from_pw_format(audio_params.info.raw.format);
+        s->frame.sample_rate = audio_params.info.raw.rate;
+        s->frame.max_size = s->frame.ch_count * s->frame.bps * s->frame.sample_rate;
+        s->frame_data.resize(s->frame.max_size);
+        s->frame.data = s->frame_data.data();
 
         std::byte buffer[1024];
         auto pod_builder = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
 
-        unsigned buffer_size = (s->buf_len_ms * s->sample_rate / 1000) * s->ch_count * s->bps;
+        unsigned buffer_size = (s->buf_len_ms * s->frame.sample_rate / 1000) * s->frame.ch_count * s->frame.bps;
 
         log_msg(LOG_LEVEL_VERBOSE, MOD_NAME "Requesting buffer size %u\n", buffer_size);
 
@@ -137,7 +147,7 @@ static void on_param_changed(void *state, uint32_t id, const struct spa_pod *par
                         SPA_TYPE_OBJECT_ParamBuffers, SPA_PARAM_Buffers,
                         SPA_PARAM_BUFFERS_blocks, SPA_POD_Int(1),
                         SPA_PARAM_BUFFERS_size, SPA_POD_CHOICE_RANGE_Int(buffer_size, 0, INT32_MAX),
-                        SPA_PARAM_BUFFERS_stride, SPA_POD_Int(s->ch_count * s->bps));
+                        SPA_PARAM_BUFFERS_stride, SPA_POD_Int(s->frame.ch_count * s->frame.bps));
 
         if(!new_params){
                 log_msg(LOG_LEVEL_ERROR, MOD_NAME "Failed to build pw buffer params pod\n");
@@ -227,13 +237,6 @@ static void *audio_cap_pipewire_init(struct module *parent, const char *cfg){
 
         spa_audio_format format = get_pw_format_from_bps(s->bps);
 
-        s->frame.ch_count = s->ch_count;
-        s->frame.bps = s->bps;
-        s->frame.sample_rate = s->sample_rate;
-        s->frame.max_size = s->frame.ch_count * s->frame.bps * s->frame.sample_rate;
-        s->frame_data.resize(s->frame.max_size);
-        s->frame.data = s->frame_data.data();
-
         pw_properties_setf(props, PW_KEY_NODE_RATE, "1/%u", s->sample_rate);
         pw_properties_setf(props, PW_KEY_NODE_LATENCY, "%u/%u", s->quant, s->sample_rate);