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pcm: file: add infile read support for mmap mode

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mmap_begin callback is used to copy data from input file to mmaped
buffer

guard for corner use of api (multiple mmap_begin calls by user) is
introduced to check if next continuous buffer was already overwritten

buffer is overwritten with input file data only in case of stream capture

Signed-off-by: Adam Miartus <amiartus@de.adit-jv.com>
Reviewed-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Adam Miartus 2019-05-23 15:00:40 +02:00 • committed by Takashi Iwai
parent e520f45480
commit fe7ff721a9
1 changed files with 31 additions and 0 deletions
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31
src/pcm/pcm_file.c
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@ -88,6 +88,7 @@ typedef struct {
size_t buffer_bytes;
struct wav_fmt wav_header;
size_t filelen;
char ifmmap_overwritten;
} snd_pcm_file_t;
#if __BYTE_ORDER == __LITTLE_ENDIAN
@ -630,6 +631,8 @@ static snd_pcm_sframes_t snd_pcm_file_mmap_commit(snd_pcm_t *pcm,
const snd_pcm_channel_area_t *areas;
snd_pcm_sframes_t result;
file->ifmmap_overwritten = 0;
result = snd_pcm_mmap_begin(file->gen.slave, &areas, &ofs, &siz);
if (result >= 0) {
assert(ofs == offset && siz == size);
@ -640,6 +643,32 @@ static snd_pcm_sframes_t snd_pcm_file_mmap_commit(snd_pcm_t *pcm,
return result;
}
static int snd_pcm_file_mmap_begin(snd_pcm_t *pcm, const snd_pcm_channel_area_t **areas,
snd_pcm_uframes_t *offset, snd_pcm_uframes_t *frames)
{
snd_pcm_file_t *file = pcm->private_data;
snd_pcm_channel_area_t areas_if[pcm->channels];
snd_pcm_uframes_t frames_if;
void *buffer = NULL;
int result;
result = snd_pcm_mmap_begin(file->gen.slave, areas, offset, frames);
if (result < 0)
return result;
if (pcm->stream != SND_PCM_STREAM_CAPTURE)
return result;
/* user may run mmap_begin without mmap_commit multiple times in row */
if (file->ifmmap_overwritten)
return result;
file->ifmmap_overwritten = 1;
snd_pcm_file_areas_read_infile(pcm, *areas, *offset, *frames);
return result;
}
static int snd_pcm_file_hw_free(snd_pcm_t *pcm)
{
snd_pcm_file_t *file = pcm->private_data;
@ -666,6 +695,7 @@ static int snd_pcm_file_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params)
file->wbuf_size = slave->buffer_size * 2;
file->wbuf_size_bytes = snd_pcm_frames_to_bytes(slave, file->wbuf_size);
file->wbuf_used_bytes = 0;
file->ifmmap_overwritten = 0;
assert(!file->wbuf);
file->wbuf = malloc(file->wbuf_size_bytes);
if (file->wbuf == NULL) {
@ -777,6 +807,7 @@ static const snd_pcm_fast_ops_t snd_pcm_file_fast_ops = {
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_revents = snd_pcm_generic_poll_revents,
.htimestamp = snd_pcm_generic_htimestamp,
.mmap_begin = snd_pcm_file_mmap_begin,
};
/**