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authorMikhail Burakov <mburakov@mailbox.org>2024-05-19 10:14:23 +0200
committerMikhail Burakov <mburakov@mailbox.org>2024-05-19 10:15:12 +0200
commit3a4e9a0818e2e352eb87b13a250c9ad6e67524b0 (patch)
tree305545a50aaa19a05cd657b5cc249eabc627a3f2 /audio.c
parent191dd1097cb9b8827e53ecd450c31d60e63e91f3 (diff)
Change alsa audio output to pipewire
Diffstat (limited to 'audio.c')
-rw-r--r--audio.c199
1 files changed, 126 insertions, 73 deletions
diff --git a/audio.c b/audio.c
index e93dd4a..6ca2004 100644
--- a/audio.c
+++ b/audio.c
@@ -17,123 +17,176 @@
#include "audio.h"
-#include <alsa/asoundlib.h>
#include <errno.h>
-#include <stdatomic.h>
-#include <stddef.h>
-#include <stdint.h>
+#include <pipewire/pipewire.h>
+#include <spa/param/audio/raw-utils.h>
+#include <spa/utils/result.h>
+#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
-#include <threads.h>
#include "atomic_queue.h"
#include "toolbox/utils.h"
struct AudioContext {
- const char* device;
- atomic_bool running;
struct AtomicQueue queue;
- atomic_uint_fast64_t latency;
- thrd_t thread;
-};
+ struct pw_thread_loop* pw_thread_loop;
+ struct pw_stream* pw_stream;
-static int AudioContextThreadProc(void* arg) {
- struct AudioContext* context = arg;
+ size_t queue_samples_sum;
+ size_t queue_samples_count;
+};
- snd_pcm_t* pcm = NULL;
- int err = snd_pcm_open(&pcm, context->device, SND_PCM_STREAM_PLAYBACK, 0);
- if (err) {
- LOG("Failed to open pcm (%s)", snd_strerror(err));
- atomic_store_explicit(&context->running, 0, memory_order_relaxed);
- return 0;
+static void OnStreamProcess(void* data) {
+ struct AudioContext* audio_context = data;
+ struct pw_buffer* pw_buffer =
+ pw_stream_dequeue_buffer(audio_context->pw_stream);
+ if (!pw_buffer) {
+ LOG("Failed to dequeue stream buffer");
+ return;
}
- // TODO(mburakov): Read audio configuration from the server.
- err = snd_pcm_set_params(pcm, SND_PCM_FORMAT_S16_LE,
- SND_PCM_ACCESS_RW_INTERLEAVED, 2, 48000, 1, 10000);
- if (err) {
- LOG("Failed to set pcm params (%s)", snd_strerror(err));
- atomic_store_explicit(&context->running, 0, memory_order_relaxed);
- goto rollback_pcm;
- }
+ static const size_t stride = sizeof(int16_t) * 2;
+ struct spa_data* spa_data = &pw_buffer->buffer->datas[0];
+ size_t requested =
+ MIN(pw_buffer->requested, spa_data->maxsize / stride) * stride;
+ size_t available =
+ AtomicQueueRead(&audio_context->queue, spa_data->data, requested);
- while (atomic_load_explicit(&context->running, memory_order_relaxed)) {
- // TODO(mburakov): Frame size depends on dynamic audio configuration.
- static const unsigned frame_size = sizeof(int16_t) * 2;
- uint8_t buffer[480 * frame_size];
-
- size_t size = AtomicQueueRead(&context->queue, buffer, sizeof(buffer));
- if (size < sizeof(buffer)) {
- // LOG("Audio queue underflow!");
- memset(buffer + size, 0, sizeof(buffer) - size);
- uint64_t micros = (sizeof(buffer) - size) * 1000 / frame_size / 48;
- atomic_fetch_add_explicit(&context->latency, micros,
- memory_order_relaxed);
- }
-
- for (snd_pcm_uframes_t offset = 0; offset < sizeof(buffer) / frame_size;) {
- snd_pcm_sframes_t nframes =
- snd_pcm_writei(pcm, buffer + offset * frame_size,
- sizeof(buffer) / frame_size - offset);
- if (nframes < 0) {
- LOG("Failed to write pcm (%s)", snd_strerror((int)nframes));
- atomic_store_explicit(&context->running, 0, memory_order_relaxed);
- goto rollback_pcm;
- }
- offset += (snd_pcm_uframes_t)nframes;
- }
+ if (available < requested) {
+ // LOG("Audio queue underflow (%zu < %zu)!", available, requested);
+ memset((uint8_t*)spa_data->data + available, 0, requested - available);
}
-rollback_pcm:
- snd_pcm_close(pcm);
- return 0;
+ spa_data->chunk->offset = 0;
+ spa_data->chunk->stride = stride;
+ spa_data->chunk->size = (uint32_t)requested;
+ pw_stream_queue_buffer(audio_context->pw_stream, pw_buffer);
+ return;
}
-struct AudioContext* AudioContextCreate(const char* device) {
+struct AudioContext* AudioContextCreate(size_t queue_size) {
+ pw_init(0, NULL);
struct AudioContext* audio_context = malloc(sizeof(struct AudioContext));
if (!audio_context) {
- LOG("Failed to allocate context (%s)", strerror(errno));
+ LOG("Failed to allocate audio context (%s)", strerror(errno));
return NULL;
}
- audio_context->device = device;
- atomic_init(&audio_context->running, 1);
- if (!AtomicQueueCreate(&audio_context->queue, 4800 * sizeof(int16_t) * 2)) {
- LOG("Failed to create queue (%s)", strerror(errno));
- goto rollback_context;
+ if (!AtomicQueueCreate(&audio_context->queue,
+ queue_size * sizeof(int16_t) * 2)) {
+ LOG("Failed to create buffer queue (%s)", strerror(errno));
+ goto rollback_audio_context;
}
- if (thrd_create(&audio_context->thread, AudioContextThreadProc,
- audio_context) != thrd_success) {
- LOG("Failed to create thread (%s)", strerror(errno));
+ audio_context->pw_thread_loop = pw_thread_loop_new("audio-playback", NULL);
+ if (!audio_context->pw_thread_loop) {
+ LOG("Failed to create pipewire thread loop");
goto rollback_queue;
}
+
+ pw_thread_loop_lock(audio_context->pw_thread_loop);
+ int err = pw_thread_loop_start(audio_context->pw_thread_loop);
+ if (err) {
+ LOG("Failed to start pipewire thread loop (%s)", spa_strerror(err));
+ pw_thread_loop_unlock(audio_context->pw_thread_loop);
+ goto rollback_thread_loop;
+ }
+
+ // TOOD(mburakov): Read these from the commandline?
+ struct pw_properties* pw_properties = pw_properties_new(
+#define _(...) __VA_ARGS__
+ _(PW_KEY_MEDIA_TYPE, "Audio"), _(PW_KEY_MEDIA_CATEGORY, "Playback"),
+ _(PW_KEY_MEDIA_ROLE, "Game"), _(PW_KEY_NODE_LATENCY, "128/48000"), NULL
+#undef _
+ );
+ if (!pw_properties) {
+ LOG("Failed to create pipewire properties");
+ pw_thread_loop_unlock(audio_context->pw_thread_loop);
+ goto rollback_thread_loop;
+ }
+
+ static const struct pw_stream_events kPwStreamEvents = {
+ .version = PW_VERSION_STREAM_EVENTS,
+ .process = OnStreamProcess,
+ };
+ audio_context->pw_stream = pw_stream_new_simple(
+ pw_thread_loop_get_loop(audio_context->pw_thread_loop), "audio-playback",
+ pw_properties, &kPwStreamEvents, audio_context);
+ if (!audio_context->pw_stream) {
+ LOG("Failed to create pipewire stream");
+ pw_thread_loop_unlock(audio_context->pw_thread_loop);
+ goto rollback_thread_loop;
+ }
+
+ uint8_t buffer[1024];
+ struct spa_pod_builder spa_pod_builder =
+ SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
+ const struct spa_pod* params[] = {
+ spa_format_audio_raw_build(
+ &spa_pod_builder, SPA_PARAM_EnumFormat,
+ &SPA_AUDIO_INFO_RAW_INIT(.format = SPA_AUDIO_FORMAT_S16_LE,
+ .rate = 48000, .channels = 2,
+ .position = {SPA_AUDIO_CHANNEL_FL,
+ SPA_AUDIO_CHANNEL_FR})),
+ };
+ static const enum pw_stream_flags kPwStreamFlags =
+ PW_STREAM_FLAG_AUTOCONNECT | PW_STREAM_FLAG_MAP_BUFFERS |
+ PW_STREAM_FLAG_RT_PROCESS;
+ if (pw_stream_connect(audio_context->pw_stream, PW_DIRECTION_OUTPUT,
+ PW_ID_ANY, kPwStreamFlags, params, LENGTH(params))) {
+ LOG("Failed to connect pipewire stream");
+ pw_stream_destroy(audio_context->pw_stream);
+ pw_thread_loop_unlock(audio_context->pw_thread_loop);
+ goto rollback_thread_loop;
+ }
+
+ audio_context->queue_samples_sum = 0;
+ audio_context->queue_samples_count = 0;
+ pw_thread_loop_unlock(audio_context->pw_thread_loop);
return audio_context;
+rollback_thread_loop:
+ pw_thread_loop_destroy(audio_context->pw_thread_loop);
rollback_queue:
AtomicQueueDestroy(&audio_context->queue);
-rollback_context:
+rollback_audio_context:
free(audio_context);
+ pw_deinit();
return NULL;
}
bool AudioContextDecode(struct AudioContext* audio_context, const void* buffer,
size_t size) {
- if (!atomic_load_explicit(&audio_context->running, memory_order_relaxed)) {
- LOG("Audio thread was stopped early!");
- return false;
- }
if (AtomicQueueWrite(&audio_context->queue, buffer, size) < size)
LOG("Audio queue overflow!");
+ size_t queue_size =
+ atomic_load_explicit(&audio_context->queue.size, memory_order_relaxed);
+ static const size_t stride = sizeof(int16_t) * 2;
+ audio_context->queue_samples_sum += queue_size / stride;
+ audio_context->queue_samples_count++;
return true;
}
-uint64_t AudioContextGetLatency(const struct AudioContext* audio_context) {
- return atomic_load_explicit(&audio_context->latency, memory_order_relaxed);
+uint64_t AudioContextGetLatency(struct AudioContext* audio_context) {
+ size_t queue_latency = 0;
+ if (audio_context->queue_samples_count) {
+ queue_latency =
+ audio_context->queue_samples_sum / audio_context->queue_samples_count;
+ audio_context->queue_samples_sum = 0;
+ audio_context->queue_samples_count = 0;
+ }
+ // TODO(mburakov): This number is extremely optimistic, i.e. Bluetooth delays
+ // are not accounted for. Is it anyhow possible to get this information?
+ return (128 + queue_latency) * 1000000 / 48000;
}
void AudioContextDestroy(struct AudioContext* audio_context) {
- atomic_store_explicit(&audio_context->running, 0, memory_order_relaxed);
- thrd_join(audio_context->thread, NULL);
+ pw_thread_loop_lock(audio_context->pw_thread_loop);
+ pw_stream_destroy(audio_context->pw_stream);
+ pw_thread_loop_unlock(audio_context->pw_thread_loop);
+ pw_thread_loop_destroy(audio_context->pw_thread_loop);
AtomicQueueDestroy(&audio_context->queue);
free(audio_context);
+ pw_deinit();
}