pulse-server: module-pipe-source: don't queue partial samples

If the number of bytes read is not a multiple of the stride,
then partial samples may be queued. Avoid that by storing the
last partial sample (if any) in a separate buffer,
and only queue full samples.
This commit is contained in:
Barnabás Pőcze 2021-06-25 20:42:34 +02:00
parent 8a61374592
commit 73ea24a356

View file

@ -54,54 +54,65 @@ struct module_pipesrc_data {
bool do_unlink;
char *filename;
int fd;
int stride;
uint32_t stride;
uint32_t leftover_count;
uint8_t leftover[]; /* `stride` bytes for storing a partial sample */
};
static void playback_process(void *data)
{
struct module_pipesrc_data *impl = data;
struct pw_buffer *b;
struct spa_buffer *buf;
int bytes_read;
uint8_t *dst;
struct spa_chunk *chunk;
struct pw_buffer *buffer;
struct spa_data *d;
uint32_t left, leftover;
ssize_t bytes_read;
if ((b = pw_stream_dequeue_buffer(impl->playback)) == NULL) {
if ((buffer = pw_stream_dequeue_buffer(impl->playback)) == NULL) {
pw_log_warn("Out of playback buffers: %m");
return;
}
buf = b->buffer;
if ((dst = buf->datas[0].data) == NULL)
d = &buffer->buffer->datas[0];
if (d->data == NULL)
return;
buf->datas[0].chunk->offset = 0;
buf->datas[0].chunk->stride = impl->stride;
buf->datas[0].chunk->size = 0;
left = d->maxsize;
spa_assert(left >= impl->leftover_count);
/*
* Read from the pipe in a multiple of stride. If the number of bytes
* read is not a multiple of stride, we end up with incomplete samples
* in the buffer. This is especially noticeable when using S24LE.
*
* Trying to read (buf->datas[0].maxsize / stride) * stride does not
* necessarily result in bytes_read being a multiple of stride
* resulting in us being left with incomplete samples in the buffer
* again.
*/
bytes_read = read(impl->fd, dst, impl->stride * 4096);
chunk = d->chunk;
chunk->offset = 0;
chunk->stride = impl->stride;
chunk->size = impl->leftover_count;
memcpy(d->data, impl->leftover, impl->leftover_count);
left -= impl->leftover_count;
bytes_read = read(impl->fd, SPA_PTROFF(d->data, chunk->size, void), left);
if (bytes_read < 0) {
if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK) {
pw_log_debug("Error in reading from pipe source: %s",
spa_strerror(-errno));
} else {
pw_log_error("Failed to read from pipe source: %s",
spa_strerror(-errno));
}
} else {
buf->datas[0].chunk->size = bytes_read;
const bool important = !(errno == EINTR
|| errno == EAGAIN
|| errno == EWOULDBLOCK);
if (important)
pw_log_warn("failed to read from pipe (%s): %s",
impl->filename, strerror(errno));
}
else {
chunk->size += bytes_read;
}
pw_stream_queue_buffer(impl->playback, b);
leftover = chunk->size % impl->stride;
chunk->size -= leftover;
memcpy(impl->leftover, SPA_PTROFF(d->data, chunk->size, void), leftover);
impl->leftover_count = leftover;
pw_stream_queue_buffer(impl->playback, buffer);
}
static void on_core_error(void *data, uint32_t id, int seq, int res, const char *message)
@ -345,7 +356,7 @@ struct module *create_module_pipe_source(struct impl *impl, const char *argument
if ((str = pw_properties_get(props, PW_KEY_MEDIA_CLASS)) == NULL)
pw_properties_set(props, PW_KEY_MEDIA_CLASS, "Audio/Source");
module = module_new(impl, &module_pipesource_methods, sizeof(*d));
module = module_new(impl, &module_pipesource_methods, sizeof(*d) + stride);
if (module == NULL) {
res = -errno;
goto out;