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Hey - first somehow working version (for first client)...

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This commit is contained in:
Jaroslav Kysela 2003-02-11 21:28:23 +00:00
parent af89cefd99
commit 121da3e301
1 changed files with 95 additions and 15 deletions
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110
src/pcm/pcm_dmix.c
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@ -473,19 +473,74 @@ static int client_discard(snd_pcm_dmix_t *dmix)
* ring buffer operation
*/
/*
* the main function of this plugin: mixing
* FIXME: optimize it for different architectures
*/
static void mix_areas(const snd_pcm_channel_area_t *src_areas,
const snd_pcm_channel_area_t *dst_areas,
unsigned int channels,
snd_pcm_uframes_t src_ofs,
snd_pcm_uframes_t dst_ofs,
snd_pcm_uframes_t size)
{
register signed int sample;
signed short *src, *dst;
unsigned int src_step, dst_step;
unsigned int chn, count;
for (chn = 0; chn < channels; chn++) {
src_step = src_areas[chn].step / 8;
dst_step = dst_areas[chn].step / 8;
src = (signed short *)(((char *)src_areas[chn].addr + src_areas[chn].first / 8) + (src_ofs * src_step));
dst = (signed short *)(((char *)dst_areas[chn].addr + dst_areas[chn].first / 8) + (dst_ofs * dst_step));
count = 0;
while (count++ < size) {
/* FIXME: it's pretty ugly, because the other process might modify our value between
read / write session - especially on MP machines */
sample = *dst + *src;
if (sample > 0x7fff)
sample = 0x7fff;
if (sample < -0x8000)
sample = -0x8000;
*dst = sample;
((char *)src) += src_step;
((char *)dst) += dst_step;
}
}
}
/*
* synchronize shm ring buffer with hardware
*/
static void snd_pcm_dmix_sync_area(snd_pcm_t *pcm, snd_pcm_uframes_t size)
{
snd_pcm_dmix_t *dmix = pcm->private_data;
snd_pcm_uframes_t appl_ptr;
snd_pcm_uframes_t appl_ptr, slave_appl_ptr, transfer;
const snd_pcm_channel_area_t *src_areas, *dst_areas;
/* get the start of update area */
appl_ptr = dmix->appl_ptr - size;
if (appl_ptr > pcm->boundary)
appl_ptr += pcm->boundary;
appl_ptr %= pcm->buffer_size;
/* add sample areas here */
src_areas = snd_pcm_mmap_areas(pcm);
dst_areas = snd_pcm_mmap_areas(dmix->spcm);
slave_appl_ptr = dmix->slave_appl_ptr % dmix->spcm->buffer_size;
dmix->slave_appl_ptr += size;
dmix->slave_appl_ptr %= dmix->spcm->boundary;
while (size > 0) {
transfer = appl_ptr + size > pcm->buffer_size ? pcm->buffer_size - appl_ptr : size;
transfer = slave_appl_ptr + transfer > dmix->spcm->buffer_size ? dmix->spcm->buffer_size - slave_appl_ptr : transfer;
size -= transfer;
mix_areas(src_areas, dst_areas, pcm->channels, appl_ptr, slave_appl_ptr, transfer);
slave_appl_ptr += transfer;
slave_appl_ptr %= dmix->spcm->buffer_size;
appl_ptr += transfer;
appl_ptr %= pcm->buffer_size;
}
}
/*
@ -514,6 +569,7 @@ static int snd_pcm_dmix_sync_ptr(snd_pcm_t *pcm)
if ((avail = snd_pcm_mmap_playback_avail(pcm)) >= pcm->stop_threshold) {
dmix->state = SND_PCM_STATE_XRUN;
dmix->avail_max = avail;
printf("XRUN?\n");
return -EPIPE;
}
if (avail > dmix->avail_max)
@ -769,12 +825,14 @@ static int snd_pcm_dmix_reset(snd_pcm_t *pcm)
snd_pcm_dmix_t *dmix = pcm->private_data;
dmix->hw_ptr %= pcm->period_size;
dmix->appl_ptr = dmix->hw_ptr;
dmix->slave_appl_ptr = dmix->slave_hw_ptr = *dmix->spcm->hw.ptr;
return 0;
}
static int snd_pcm_dmix_start(snd_pcm_t *pcm)
{
snd_pcm_dmix_t *dmix = pcm->private_data;
snd_pcm_sframes_t avail;
int err;
if (dmix->state != SND_PCM_STATE_PREPARED)
@ -783,8 +841,13 @@ static int snd_pcm_dmix_start(snd_pcm_t *pcm)
if (err < 0)
return err;
dmix->state = SND_PCM_STATE_RUNNING;
dmix->slave_hw_ptr = *dmix->spcm->hw.ptr;
snd_pcm_dmix_sync_area(pcm, dmix->appl_ptr < pcm->buffer_size ? dmix->appl_ptr : pcm->buffer_size);
dmix->slave_appl_ptr = dmix->slave_hw_ptr = *dmix->spcm->hw.ptr;
avail = snd_pcm_mmap_playback_hw_avail(pcm);
if (avail < 0)
return 0;
if (avail > (snd_pcm_sframes_t)pcm->buffer_size)
avail = pcm->buffer_size;
snd_pcm_dmix_sync_area(pcm, avail);
return 0;
}
@ -793,6 +856,7 @@ static int snd_pcm_dmix_drop(snd_pcm_t *pcm)
snd_pcm_dmix_t *dmix = pcm->private_data;
if (dmix->state == SND_PCM_STATE_OPEN)
return -EBADFD;
snd_timer_stop(dmix->timer);
dmix->state = SND_PCM_STATE_SETUP;
return 0;
}
@ -802,6 +866,7 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm)
snd_pcm_dmix_t *dmix = pcm->private_data;
if (dmix->state == SND_PCM_STATE_OPEN)
return -EBADFD;
snd_timer_stop(dmix->timer);
dmix->state = SND_PCM_STATE_SETUP;
return 0;
}
@ -813,10 +878,12 @@ static int snd_pcm_dmix_pause(snd_pcm_t *pcm, int enable)
if (dmix->state != SND_PCM_STATE_RUNNING)
return -EBADFD;
dmix->state = SND_PCM_STATE_PAUSED;
snd_timer_stop(dmix->timer);
} else {
if (dmix->state != SND_PCM_STATE_PAUSED)
return -EBADFD;
dmix->state = SND_PCM_STATE_RUNNING;
snd_timer_start(dmix->timer);
}
return 0;
}
@ -882,31 +949,38 @@ static snd_pcm_sframes_t snd_pcm_dmix_mmap_commit(snd_pcm_t *pcm,
snd_pcm_uframes_t offset ATTRIBUTE_UNUSED,
snd_pcm_uframes_t size)
{
snd_pcm_dmix_t *dmix = pcm->private_data;
int err;
snd_pcm_mmap_appl_forward(pcm, size);
err = snd_pcm_dmix_sync_ptr(pcm);
if (err < 0)
return err;
/* ok, we commit the changes after the validation of area */
/* it's intended, although the result might be crappy */
snd_pcm_dmix_sync_area(pcm, size);
if (dmix->state == SND_PCM_STATE_RUNNING) {
err = snd_pcm_dmix_sync_ptr(pcm);
if (err < 0)
return err;
/* ok, we commit the changes after the validation of area */
/* it's intended, although the result might be crappy */
snd_pcm_dmix_sync_area(pcm, size);
}
return size;
}
static snd_pcm_sframes_t snd_pcm_dmix_avail_update(snd_pcm_t *pcm ATTRIBUTE_UNUSED)
{
snd_pcm_dmix_t *dmix = pcm->private_data;
int err;
err = snd_pcm_dmix_sync_ptr(pcm);
if (err < 0)
return err;
if (dmix->state == SND_PCM_STATE_RUNNING) {
err = snd_pcm_dmix_sync_ptr(pcm);
if (err < 0)
return err;
}
return snd_pcm_mmap_playback_avail(pcm);
}
static void snd_pcm_dmix_dump(snd_pcm_t *pcm, snd_output_t *out)
{
snd_pcm_dmix_t *dmix = pcm->private_data;
snd_output_printf(out, "Direct Stream Mixing PCM\n");
if (pcm->setup) {
snd_output_printf(out, "\nIts setup is:\n");
@ -973,11 +1047,11 @@ static int snd_pcm_dmix_initialize_slave(snd_pcm_dmix_t *dmix, snd_pcm_t *spcm,
SNDERR("snd_pcm_hw_params_any failed");
return ret;
}
ret = snd_pcm_hw_params_set_access(spcm, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
ret = snd_pcm_hw_params_set_access(spcm, hw_params, SND_PCM_ACCESS_MMAP_INTERLEAVED);
if (ret < 0) {
ret = snd_pcm_hw_params_set_access(spcm, hw_params, SND_PCM_ACCESS_RW_NONINTERLEAVED);
ret = snd_pcm_hw_params_set_access(spcm, hw_params, SND_PCM_ACCESS_MMAP_NONINTERLEAVED);
if (ret < 0) {
SNDERR("slave plugin does not support interleaved or noninterleaved access");
SNDERR("slave plugin does not support mmap interleaved or mmap noninterleaved access");
return ret;
}
}
@ -1081,6 +1155,8 @@ static int snd_pcm_dmix_initialize_slave(snd_pcm_dmix_t *dmix, snd_pcm_t *spcm,
return ret;
}
sleep(3);
return 0;
}
@ -1247,6 +1323,7 @@ int snd_pcm_dmix_open(snd_pcm_t **pcmp, const char *name,
dmix->shmptr->type = spcm->type;
pcm->mmap_rw = 1;
snd_pcm_set_hw_ptr(pcm, &dmix->hw_ptr, -1, 0);
snd_pcm_set_appl_ptr(pcm, &dmix->appl_ptr, -1, 0);
@ -1391,6 +1468,9 @@ int _snd_pcm_dmix_open(snd_pcm_t **pcmp, const char *name,
SND_PCM_HW_PARAM_PERIODS, 0, &params.periods);
if (err < 0)
return err;
assert(params.format == SND_PCM_FORMAT_S16); /* sorry, limited features */
params.period_size = psize;
params.buffer_size = bsize;
err = snd_pcm_dmix_open(pcmp, name, ipc_key, &params, root, sconf, stream, mode);