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Added support for auto mmap. Much improved version of pcm_share (without async signals)

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This commit is contained in:
Abramo Bagnara 2000-10-20 09:18:13 +00:00
parent 8d3919707e
commit 9a435c2d93
14 changed files with 621 additions and 328 deletions
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90
src/pcm/pcm.c
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@ -26,6 +26,8 @@
#include <stdarg.h>
#include <sys/ioctl.h>
#include <sys/poll.h>
#include <sys/shm.h>
#include <sys/mman.h>
#include <dlfcn.h>
#include "pcm_local.h"
#include "list.h"
@ -138,27 +140,39 @@ int snd_pcm_channel_setup(snd_pcm_t *pcm, snd_pcm_channel_setup_t *setup)
return pcm->ops->channel_setup(pcm->op_arg, setup);
}
int snd_pcm_params(snd_pcm_t *pcm, snd_pcm_params_t *params)
int _snd_pcm_params(snd_pcm_t *pcm, snd_pcm_params_t *params)
{
int err;
snd_pcm_setup_t setup;
int mmap = 0;
assert(pcm && params);
if ((err = pcm->ops->params(pcm->op_arg, params)) < 0)
return err;
pcm->valid_setup = 0;
return snd_pcm_setup(pcm, &setup);
}
int snd_pcm_params_mmap(snd_pcm_t *pcm, snd_pcm_params_t *params)
{
int err;
if (pcm->mmap_info) {
mmap = 1;
err = snd_pcm_munmap(pcm);
if (err < 0)
return err;
}
if ((err = pcm->ops->params(pcm->op_arg, params)) < 0)
return err;
pcm->valid_setup = 0;
err = snd_pcm_setup(pcm, &setup);
if (pcm->mmap_auto || mmap)
snd_pcm_mmap(pcm);
err = _snd_pcm_params(pcm, params);
if (pcm->valid_setup)
snd_pcm_mmap(pcm);
return err;
}
int snd_pcm_params(snd_pcm_t *pcm, snd_pcm_params_t *params)
{
assert(pcm && params);
if (pcm->mmap_auto)
return snd_pcm_params_mmap(pcm, params);
assert(!pcm->mmap_info);
return _snd_pcm_params(pcm, params);
}
int snd_pcm_status(snd_pcm_t *pcm, snd_pcm_status_t *status)
{
assert(pcm && status);
@ -227,7 +241,7 @@ int snd_pcm_set_avail_min(snd_pcm_t *pcm, size_t frames)
int err;
assert(pcm);
assert(pcm->valid_setup);
assert(frames > 0 && frames < pcm->setup.buffer_size);
assert(frames > 0);
err = pcm->fast_ops->set_avail_min(pcm->fast_op_arg, frames);
if (err < 0)
return err;
@ -1069,6 +1083,60 @@ ssize_t snd_pcm_write_areas(snd_pcm_t *pcm, snd_pcm_channel_area_t *areas,
return err;
}
int snd_pcm_alloc_user_mmap(snd_pcm_t *pcm, snd_pcm_mmap_info_t *i)
{
i->type = SND_PCM_MMAP_USER;
i->size = snd_pcm_frames_to_bytes(pcm, pcm->setup.buffer_size);
i->u.user.shmid = shmget(IPC_PRIVATE, i->size, 0666);
if (i->u.user.shmid < 0) {
SYSERR("shmget failed");
return -errno;
}
i->addr = shmat(i->u.user.shmid, 0, 0);
if (i->addr == (void*) -1) {
SYSERR("shmat failed");
return -errno;
}
return 0;
}
int snd_pcm_alloc_kernel_mmap(snd_pcm_t *pcm, snd_pcm_mmap_info_t *i, int fd)
{
i->type = SND_PCM_MMAP_KERNEL;
i->size = pcm->setup.mmap_bytes;
i->addr = mmap(NULL, pcm->setup.mmap_bytes,
PROT_WRITE | PROT_READ,
MAP_FILE|MAP_SHARED,
fd, SND_PCM_MMAP_OFFSET_DATA);
if (i->addr == MAP_FAILED ||
i->addr == NULL) {
SYSERR("data mmap failed");
return -errno;
}
i->u.kernel.fd = fd;
return 0;
}
int snd_pcm_free_mmap(snd_pcm_t *pcm, snd_pcm_mmap_info_t *i)
{
if (i->type == SND_PCM_MMAP_USER) {
if (shmdt(i->addr) < 0) {
SYSERR("shmdt failed");
return -errno;
}
if (shmctl(i->u.user.shmid, IPC_RMID, 0) < 0) {
SYSERR("shmctl IPC_RMID failed");
return -errno;
}
} else {
if (munmap(pcm->mmap_info->addr, pcm->mmap_info->size) < 0) {
SYSERR("data munmap failed");
return -errno;
}
}
return 0;
}
void snd_pcm_error(const char *file, int line, const char *function, int err, const char *fmt, ...)
{
va_list arg;