Rewritten mmap_{read,write} following alsa-driver current code

This commit is contained in:
Abramo Bagnara 2001-01-20 12:56:30 +00:00
parent 4086362a33
commit b4e80abc53
2 changed files with 114 additions and 61 deletions

View file

@ -1045,117 +1045,170 @@ int snd_pcm_areas_copy(const snd_pcm_channel_area_t *src_areas, snd_pcm_uframes_
}
snd_pcm_sframes_t snd_pcm_read_areas(snd_pcm_t *pcm, const snd_pcm_channel_area_t *areas,
snd_pcm_uframes_t offset, snd_pcm_uframes_t size,
snd_pcm_xfer_areas_func_t func)
snd_pcm_uframes_t offset, snd_pcm_uframes_t size,
snd_pcm_xfer_areas_func_t func)
{
snd_pcm_uframes_t xfer = 0;
snd_pcm_sframes_t err = 0;
int err = 0;
int state = snd_pcm_state(pcm);
assert(size > 0);
assert(state >= SND_PCM_STATE_PREPARED);
if (state == SND_PCM_STATE_PREPARED &&
pcm->start_mode != SND_PCM_START_EXPLICIT) {
err = snd_pcm_start(pcm);
if (err < 0)
return err;
state = SND_PCM_STATE_RUNNING;
if (size == 0)
return 0;
if (size > pcm->xfer_align)
size -= size % pcm->xfer_align;
switch (state) {
case SND_PCM_STATE_PREPARED:
if (pcm->start_mode == SND_PCM_START_DATA) {
err = snd_pcm_start(pcm);
if (err < 0)
goto _end;
}
break;
case SND_PCM_STATE_DRAINING:
case SND_PCM_STATE_RUNNING:
break;
case SND_PCM_STATE_XRUN:
return -EPIPE;
default:
return -EBADFD;
}
while (xfer < size) {
snd_pcm_sframes_t avail;
while (size > 0) {
snd_pcm_uframes_t frames;
again:
snd_pcm_sframes_t avail;
_again:
avail = snd_pcm_avail_update(pcm);
if (avail < 0) {
err = avail;
break;
err = -EPIPE;
goto _end;
}
if ((snd_pcm_uframes_t)avail < pcm->avail_min) {
if (state != SND_PCM_STATE_RUNNING) {
if (state == SND_PCM_STATE_DRAINING) {
if (avail == 0) {
err = -EPIPE;
break;
goto _end;
}
} else if (avail == 0 ||
(size >= pcm->xfer_align &&
(snd_pcm_uframes_t) avail < pcm->xfer_align)) {
if (pcm->mode & SND_PCM_NONBLOCK) {
err = -EAGAIN;
break;
goto _end;
}
err = snd_pcm_wait(pcm, -1);
if (err < 0)
break;
state = snd_pcm_state(pcm);
goto again;
goto _again;
}
frames = size - xfer;
if (frames > (snd_pcm_uframes_t)avail)
if ((snd_pcm_uframes_t) avail > pcm->xfer_align)
avail -= avail % pcm->xfer_align;
frames = size;
if (frames > (snd_pcm_uframes_t) avail)
frames = avail;
assert(frames != 0);
err = func(pcm, areas, offset, frames, 0);
if (err < 0)
break;
assert((snd_pcm_uframes_t)err == frames);
xfer += err;
offset += err;
offset += frames;
size -= frames;
xfer += frames;
#if 0
state = snd_pcm_state(pcm);
if (state == SND_PCM_STATE_XRUN) {
err = -EPIPE;
goto _end;
}
#endif
}
if (xfer > 0)
return xfer;
return err;
_end:
return xfer > 0 ? xfer : err;
}
snd_pcm_sframes_t snd_pcm_write_areas(snd_pcm_t *pcm, const snd_pcm_channel_area_t *areas,
snd_pcm_uframes_t offset, snd_pcm_uframes_t size,
snd_pcm_xfer_areas_func_t func)
snd_pcm_uframes_t offset, snd_pcm_uframes_t size,
snd_pcm_xfer_areas_func_t func)
{
snd_pcm_uframes_t xfer = 0;
snd_pcm_sframes_t err = 0;
int err = 0;
int state = snd_pcm_state(pcm);
assert(size > 0);
assert(state >= SND_PCM_STATE_PREPARED);
while (xfer < size) {
snd_pcm_sframes_t avail;
if (size == 0)
return 0;
if (size > pcm->xfer_align)
size -= size % pcm->xfer_align;
switch (state) {
case SND_PCM_STATE_PREPARED:
case SND_PCM_STATE_RUNNING:
break;
case SND_PCM_STATE_XRUN:
return -EPIPE;
default:
return -EBADFD;
}
while (size > 0) {
snd_pcm_uframes_t frames;
again:
if (state == SND_PCM_STATE_XRUN) {
err = -EPIPE;
break;
}
snd_pcm_sframes_t avail;
_again:
avail = snd_pcm_avail_update(pcm);
if (avail < 0) {
err = avail;
break;
err = -EPIPE;
goto _end;
}
if ((snd_pcm_uframes_t)avail < pcm->avail_min) {
if (state != SND_PCM_STATE_RUNNING) {
if (state == SND_PCM_STATE_PREPARED) {
if (avail == 0) {
err = -EPIPE;
break;
goto _end;
}
} else if (avail == 0 ||
(size >= pcm->xfer_align &&
(snd_pcm_uframes_t) avail < pcm->xfer_align)) {
if (pcm->mode & SND_PCM_NONBLOCK) {
err = -EAGAIN;
break;
goto _end;
}
err = snd_pcm_wait(pcm, -1);
if (err < 0)
break;
state = snd_pcm_state(pcm);
goto again;
goto _again;
}
frames = size - xfer;
if (frames > (snd_pcm_uframes_t)avail)
if ((snd_pcm_uframes_t) avail > pcm->xfer_align)
avail -= avail % pcm->xfer_align;
frames = size;
if (frames > (snd_pcm_uframes_t) avail)
frames = avail;
assert(frames != 0);
err = func(pcm, areas, offset, frames, 0);
if (err < 0)
break;
assert((snd_pcm_uframes_t)err == frames);
xfer += err;
offset += err;
offset += frames;
size -= frames;
xfer += frames;
#if 0
state = snd_pcm_state(pcm);
if (state == SND_PCM_STATE_XRUN) {
err = -EPIPE;
goto _end;
}
#endif
if (state == SND_PCM_STATE_PREPARED &&
pcm->start_mode != SND_PCM_START_EXPLICIT) {
pcm->start_mode == SND_PCM_START_DATA) {
err = snd_pcm_start(pcm);
if (err < 0)
break;
state = SND_PCM_STATE_RUNNING;
goto _end;
}
}
if (xfer > 0)
return xfer;
return err;
_end:
return xfer > 0 ? xfer : err;
}
snd_pcm_uframes_t _snd_pcm_mmap_hw_ptr(snd_pcm_t *pcm)

View file

@ -134,10 +134,10 @@ void snd_pcm_mmap_hw_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
}
snd_pcm_sframes_t snd_pcm_mmap_write_areas(snd_pcm_t *pcm,
const snd_pcm_channel_area_t *areas,
snd_pcm_uframes_t offset,
snd_pcm_uframes_t size,
snd_pcm_uframes_t *slave_sizep)
const snd_pcm_channel_area_t *areas,
snd_pcm_uframes_t offset,
snd_pcm_uframes_t size,
snd_pcm_uframes_t *slave_sizep)
{
snd_pcm_uframes_t xfer;
if (slave_sizep && *slave_sizep < size)