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alsa-lib/src/pcm/pcm_shm.c
Jaroslav Kysela 5b9041bced Change FSF address (Franklin Street) 
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2017-11-14 14:29:26 +01:00

907 lines
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/**
* \file pcm/pcm_shm.c
* \ingroup PCM_Plugins
* \brief PCM Shared Memory Plugin Interface
* \author Abramo Bagnara <abramo@alsa-project.org>
* \date 2000-2001
*/
/*
* PCM - Shared Memory Client
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
*
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <limits.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/shm.h>
#include <sys/socket.h>
#include <poll.h>
#include <sys/un.h>
#include <sys/mman.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netdb.h>
#include "aserver.h"
#ifndef PIC
/* entry for static linking */
const char *_snd_module_pcm_shm = "";
#endif
#ifndef DOC_HIDDEN
typedef struct {
int socket;
volatile snd_pcm_shm_ctrl_t *ctrl;
} snd_pcm_shm_t;
#endif
static long snd_pcm_shm_action_fd0(snd_pcm_t *pcm, int *fd)
{
snd_pcm_shm_t *shm = pcm->private_data;
int err;
char buf[1];
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
err = write(shm->socket, buf, 1);
if (err != 1)
return -EBADFD;
err = snd_receive_fd(shm->socket, buf, 1, fd);
if (err != 1)
return -EBADFD;
if (ctrl->cmd) {
SNDERR("Server has not done the cmd");
return -EBADFD;
}
return ctrl->result;
}
static int snd_pcm_shm_new_rbptr(snd_pcm_t *pcm, snd_pcm_shm_t *shm,
snd_pcm_rbptr_t *rbptr, volatile snd_pcm_shm_rbptr_t *shm_rbptr)
{
if (!shm_rbptr->use_mmap) {
if (&pcm->hw == rbptr)
snd_pcm_set_hw_ptr(pcm, &shm_rbptr->ptr, -1, 0);
else
snd_pcm_set_appl_ptr(pcm, &shm_rbptr->ptr, -1, 0);
} else {
void *ptr;
size_t mmap_size, mmap_offset, offset;
int fd;
long result;
shm->ctrl->cmd = &pcm->hw == rbptr ? SND_PCM_IOCTL_HW_PTR_FD : SND_PCM_IOCTL_APPL_PTR_FD;
result = snd_pcm_shm_action_fd0(pcm, &fd);
if (result < 0)
return result;
mmap_size = page_ptr(shm_rbptr->offset, sizeof(snd_pcm_uframes_t), &offset, &mmap_offset);
ptr = mmap(NULL, mmap_size, PROT_READ|PROT_WRITE, MAP_FILE|MAP_SHARED, fd, mmap_offset);
if (ptr == MAP_FAILED || ptr == NULL) {
SYSERR("shm rbptr mmap failed");
return -errno;
}
if (&pcm->hw == rbptr)
snd_pcm_set_hw_ptr(pcm, (snd_pcm_uframes_t *)((char *)ptr + offset), fd, shm_rbptr->offset);
else
snd_pcm_set_appl_ptr(pcm, (snd_pcm_uframes_t *)((char *)ptr + offset), fd, shm_rbptr->offset);
}
return 0;
}
static long snd_pcm_shm_action(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
int err, result;
char buf[1];
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
if (ctrl->hw.changed || ctrl->appl.changed)
return -EBADFD;
err = write(shm->socket, buf, 1);
if (err != 1)
return -EBADFD;
err = read(shm->socket, buf, 1);
if (err != 1)
return -EBADFD;
if (ctrl->cmd) {
SNDERR("Server has not done the cmd");
return -EBADFD;
}
result = ctrl->result;
if (ctrl->hw.changed) {
err = snd_pcm_shm_new_rbptr(pcm, shm, &pcm->hw, &ctrl->hw);
if (err < 0)
return err;
ctrl->hw.changed = 0;
}
if (ctrl->appl.changed) {
err = snd_pcm_shm_new_rbptr(pcm, shm, &pcm->appl, &ctrl->appl);
if (err < 0)
return err;
ctrl->appl.changed = 0;
}
return result;
}
static long snd_pcm_shm_action_fd(snd_pcm_t *pcm, int *fd)
{
snd_pcm_shm_t *shm = pcm->private_data;
int err;
char buf[1];
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
if (ctrl->hw.changed || ctrl->appl.changed)
return -EBADFD;
err = write(shm->socket, buf, 1);
if (err != 1)
return -EBADFD;
err = snd_receive_fd(shm->socket, buf, 1, fd);
if (err != 1)
return -EBADFD;
if (ctrl->cmd) {
SNDERR("Server has not done the cmd");
return -EBADFD;
}
if (ctrl->hw.changed) {
err = snd_pcm_shm_new_rbptr(pcm, shm, &pcm->hw, &ctrl->hw);
if (err < 0)
return err;
ctrl->hw.changed = 0;
}
if (ctrl->appl.changed) {
err = snd_pcm_shm_new_rbptr(pcm, shm, &pcm->appl, &ctrl->appl);
if (err < 0)
return err;
ctrl->appl.changed = 0;
}
return ctrl->result;
}
static int snd_pcm_shm_nonblock(snd_pcm_t *pcm ATTRIBUTE_UNUSED, int nonblock ATTRIBUTE_UNUSED)
{
return 0;
}
static int snd_pcm_shm_async(snd_pcm_t *pcm, int sig, pid_t pid)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SND_PCM_IOCTL_ASYNC;
ctrl->u.async.sig = sig;
ctrl->u.async.pid = pid;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_info(snd_pcm_t *pcm, snd_pcm_info_t * info)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
// ctrl->u.info = *info;
ctrl->cmd = SNDRV_PCM_IOCTL_INFO;
err = snd_pcm_shm_action(pcm);
if (err < 0)
return err;
*info = ctrl->u.info;
return err;
}
static int snd_pcm_shm_hw_refine_cprepare(snd_pcm_t *pcm ATTRIBUTE_UNUSED, snd_pcm_hw_params_t *params ATTRIBUTE_UNUSED)
{
return 0;
}
static int snd_pcm_shm_hw_refine_sprepare(snd_pcm_t *pcm ATTRIBUTE_UNUSED, snd_pcm_hw_params_t *sparams)
{
snd_pcm_access_mask_t saccess_mask = { SND_PCM_ACCBIT_MMAP };
_snd_pcm_hw_params_any(sparams);
_snd_pcm_hw_param_set_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
&saccess_mask);
return 0;
}
static int snd_pcm_shm_hw_refine_schange(snd_pcm_t *pcm ATTRIBUTE_UNUSED, snd_pcm_hw_params_t *params,
snd_pcm_hw_params_t *sparams)
{
int err;
unsigned int links = ~SND_PCM_HW_PARBIT_ACCESS;
const snd_pcm_access_mask_t *access_mask = snd_pcm_hw_param_get_mask(params, SND_PCM_HW_PARAM_ACCESS);
if (!snd_pcm_access_mask_test(access_mask, SND_PCM_ACCESS_RW_INTERLEAVED) &&
!snd_pcm_access_mask_test(access_mask, SND_PCM_ACCESS_RW_NONINTERLEAVED)) {
err = _snd_pcm_hw_param_set_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
access_mask);
if (err < 0)
return err;
}
err = _snd_pcm_hw_params_refine(sparams, links, params);
if (err < 0)
return err;
return 0;
}
static int snd_pcm_shm_hw_refine_cchange(snd_pcm_t *pcm ATTRIBUTE_UNUSED, snd_pcm_hw_params_t *params,
snd_pcm_hw_params_t *sparams)
{
int err;
unsigned int links = ~SND_PCM_HW_PARBIT_ACCESS;
snd_pcm_access_mask_t access_mask;
snd_mask_copy(&access_mask, snd_pcm_hw_param_get_mask(sparams, SND_PCM_HW_PARAM_ACCESS));
snd_pcm_access_mask_set(&access_mask, SND_PCM_ACCESS_RW_INTERLEAVED);
snd_pcm_access_mask_set(&access_mask, SND_PCM_ACCESS_RW_NONINTERLEAVED);
err = _snd_pcm_hw_param_set_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
&access_mask);
if (err < 0)
return err;
err = _snd_pcm_hw_params_refine(params, links, sparams);
if (err < 0)
return err;
return 0;
}
static int snd_pcm_shm_hw_refine_slave(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
ctrl->u.hw_refine = *params;
ctrl->cmd = SNDRV_PCM_IOCTL_HW_REFINE;
err = snd_pcm_shm_action(pcm);
*params = ctrl->u.hw_refine;
return err;
}
static int snd_pcm_shm_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
{
return snd_pcm_hw_refine_slave(pcm, params,
snd_pcm_shm_hw_refine_cprepare,
snd_pcm_shm_hw_refine_cchange,
snd_pcm_shm_hw_refine_sprepare,
snd_pcm_shm_hw_refine_schange,
snd_pcm_shm_hw_refine_slave);
}
static int snd_pcm_shm_hw_params_slave(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
params->flags |= SND_PCM_HW_PARAMS_EXPORT_BUFFER;
ctrl->cmd = SNDRV_PCM_IOCTL_HW_PARAMS;
ctrl->u.hw_params = *params;
err = snd_pcm_shm_action(pcm);
*params = ctrl->u.hw_params;
return err;
}
static int snd_pcm_shm_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params)
{
return snd_pcm_hw_params_slave(pcm, params,
snd_pcm_shm_hw_refine_cchange,
snd_pcm_shm_hw_refine_sprepare,
snd_pcm_shm_hw_refine_schange,
snd_pcm_shm_hw_params_slave);
}
static int snd_pcm_shm_hw_free(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_HW_FREE;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_sw_params(snd_pcm_t *pcm, snd_pcm_sw_params_t * params)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
ctrl->cmd = SNDRV_PCM_IOCTL_SW_PARAMS;
ctrl->u.sw_params = *params;
err = snd_pcm_shm_action(pcm);
*params = ctrl->u.sw_params;
if (err < 0)
return err;
return err;
}
static int snd_pcm_shm_mmap(snd_pcm_t *pcm ATTRIBUTE_UNUSED)
{
return 0;
}
static int snd_pcm_shm_munmap(snd_pcm_t *pcm)
{
unsigned int c;
for (c = 0; c < pcm->channels; ++c) {
snd_pcm_channel_info_t *i = &pcm->mmap_channels[c];
unsigned int c1;
int err;
if (i->type != SND_PCM_AREA_MMAP)
continue;
if (i->u.mmap.fd < 0)
continue;
for (c1 = c + 1; c1 < pcm->channels; ++c1) {
snd_pcm_channel_info_t *i1 = &pcm->mmap_channels[c1];
if (i1->type != SND_PCM_AREA_MMAP)
continue;
if (i1->u.mmap.fd != i->u.mmap.fd)
continue;
i1->u.mmap.fd = -1;
}
err = close(i->u.mmap.fd);
if (err < 0) {
SYSERR("close failed");
return -errno;
}
}
return 0;
}
static int snd_pcm_shm_channel_info(snd_pcm_t *pcm, snd_pcm_channel_info_t * info)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
int fd;
ctrl->cmd = SNDRV_PCM_IOCTL_CHANNEL_INFO;
ctrl->u.channel_info = *info;
err = snd_pcm_shm_action_fd(pcm, &fd);
if (err < 0)
return err;
*info = ctrl->u.channel_info;
info->addr = 0;
switch (info->type) {
case SND_PCM_AREA_MMAP:
info->u.mmap.fd = fd;
break;
case SND_PCM_AREA_SHM:
break;
default:
assert(0);
break;
}
return err;
}
static int snd_pcm_shm_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
ctrl->cmd = SNDRV_PCM_IOCTL_STATUS;
// ctrl->u.status = *status;
err = snd_pcm_shm_action(pcm);
if (err < 0)
return err;
*status = ctrl->u.status;
return err;
}
static snd_pcm_state_t snd_pcm_shm_state(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SND_PCM_IOCTL_STATE;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_hwsync(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SND_PCM_IOCTL_HWSYNC;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
ctrl->cmd = SNDRV_PCM_IOCTL_DELAY;
err = snd_pcm_shm_action(pcm);
if (err < 0)
return err;
*delayp = ctrl->u.delay.frames;
return err;
}
static snd_pcm_sframes_t snd_pcm_shm_avail_update(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
ctrl->cmd = SND_PCM_IOCTL_AVAIL_UPDATE;
err = snd_pcm_shm_action(pcm);
if (err < 0)
return err;
return err;
}
static int snd_pcm_shm_htimestamp(snd_pcm_t *pcm ATTRIBUTE_UNUSED,
snd_pcm_uframes_t *avail ATTRIBUTE_UNUSED,
snd_htimestamp_t *tstamp ATTRIBUTE_UNUSED)
{
return -EIO; /* not implemented yet */
}
static int snd_pcm_shm_prepare(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_PREPARE;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_reset(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_RESET;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_start(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_START;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_drop(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_DROP;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_drain(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int err;
do {
ctrl->cmd = SNDRV_PCM_IOCTL_DRAIN;
err = snd_pcm_shm_action(pcm);
if (err != -EAGAIN)
break;
usleep(10000);
} while (1);
if (err < 0)
return err;
if (!(pcm->mode & SND_PCM_NONBLOCK))
snd_pcm_wait(pcm, -1);
return err;
}
static int snd_pcm_shm_pause(snd_pcm_t *pcm, int enable)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_PAUSE;
ctrl->u.pause.enable = enable;
return snd_pcm_shm_action(pcm);
}
static snd_pcm_sframes_t snd_pcm_shm_rewindable(snd_pcm_t *pcm ATTRIBUTE_UNUSED)
{
return 0; /* FIX ME */
}
static snd_pcm_sframes_t snd_pcm_shm_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_REWIND;
ctrl->u.rewind.frames = frames;
return snd_pcm_shm_action(pcm);
}
static snd_pcm_sframes_t snd_pcm_shm_forwardable(snd_pcm_t *pcm ATTRIBUTE_UNUSED)
{
return 0; /* FIX ME */
}
static snd_pcm_sframes_t snd_pcm_shm_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SND_PCM_IOCTL_FORWARD;
ctrl->u.forward.frames = frames;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_resume(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SNDRV_PCM_IOCTL_RESUME;
return snd_pcm_shm_action(pcm);
}
static snd_pcm_sframes_t snd_pcm_shm_mmap_commit(snd_pcm_t *pcm,
snd_pcm_uframes_t offset ATTRIBUTE_UNUSED,
snd_pcm_uframes_t size)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
ctrl->cmd = SND_PCM_IOCTL_MMAP_COMMIT;
ctrl->u.mmap_commit.offset = offset;
ctrl->u.mmap_commit.frames = size;
return snd_pcm_shm_action(pcm);
}
static int snd_pcm_shm_poll_descriptor(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int fd, err;
ctrl->cmd = SND_PCM_IOCTL_POLL_DESCRIPTOR;
err = snd_pcm_shm_action_fd(pcm, &fd);
if (err < 0)
return err;
return fd;
}
static int snd_pcm_shm_close(snd_pcm_t *pcm)
{
snd_pcm_shm_t *shm = pcm->private_data;
volatile snd_pcm_shm_ctrl_t *ctrl = shm->ctrl;
int result;
ctrl->cmd = SND_PCM_IOCTL_CLOSE;
result = snd_pcm_shm_action(pcm);
shmdt((void *)ctrl);
close(shm->socket);
close(pcm->poll_fd);
free(shm);
return result;
}
static void snd_pcm_shm_dump(snd_pcm_t *pcm, snd_output_t *out)
{
snd_output_printf(out, "Shm PCM\n");
if (pcm->setup) {
snd_output_printf(out, "Its setup is:\n");
snd_pcm_dump_setup(pcm, out);
}
}
static const snd_pcm_ops_t snd_pcm_shm_ops = {
.close = snd_pcm_shm_close,
.info = snd_pcm_shm_info,
.hw_refine = snd_pcm_shm_hw_refine,
.hw_params = snd_pcm_shm_hw_params,
.hw_free = snd_pcm_shm_hw_free,
.sw_params = snd_pcm_shm_sw_params,
.channel_info = snd_pcm_shm_channel_info,
.dump = snd_pcm_shm_dump,
.nonblock = snd_pcm_shm_nonblock,
.async = snd_pcm_shm_async,
.mmap = snd_pcm_shm_mmap,
.munmap = snd_pcm_shm_munmap,
};
static const snd_pcm_fast_ops_t snd_pcm_shm_fast_ops = {
.status = snd_pcm_shm_status,
.state = snd_pcm_shm_state,
.hwsync = snd_pcm_shm_hwsync,
.delay = snd_pcm_shm_delay,
.prepare = snd_pcm_shm_prepare,
.reset = snd_pcm_shm_reset,
.start = snd_pcm_shm_start,
.drop = snd_pcm_shm_drop,
.drain = snd_pcm_shm_drain,
.pause = snd_pcm_shm_pause,
.rewindable = snd_pcm_shm_rewindable,
.rewind = snd_pcm_shm_rewind,
.forwardable = snd_pcm_shm_forwardable,
.forward = snd_pcm_shm_forward,
.resume = snd_pcm_shm_resume,
.writei = snd_pcm_mmap_writei,
.writen = snd_pcm_mmap_writen,
.readi = snd_pcm_mmap_readi,
.readn = snd_pcm_mmap_readn,
.avail_update = snd_pcm_shm_avail_update,
.mmap_commit = snd_pcm_shm_mmap_commit,
.htimestamp = snd_pcm_shm_htimestamp,
};
static int make_local_socket(const char *filename)
{
size_t l = strlen(filename);
size_t size = offsetof(struct sockaddr_un, sun_path) + l;
struct sockaddr_un *addr = alloca(size);
int sock;
sock = socket(PF_LOCAL, SOCK_STREAM, 0);
if (sock < 0) {
SYSERR("socket failed");
return -errno;
}
addr->sun_family = AF_LOCAL;
memcpy(addr->sun_path, filename, l);
if (connect(sock, (struct sockaddr *) addr, size) < 0) {
SYSERR("connect failed");
return -errno;
}
return sock;
}
/**
* \brief Creates a new shared memory PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param sockname Unix socket name
* \param sname Server name
* \param stream PCM Stream
* \param mode PCM Mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name,
const char *sockname, const char *sname,
snd_pcm_stream_t stream, int mode)
{
snd_pcm_t *pcm;
snd_pcm_shm_t *shm = NULL;
snd_client_open_request_t *req;
snd_client_open_answer_t ans;
size_t snamelen, reqlen;
int err;
int result;
snd_pcm_shm_ctrl_t *ctrl = NULL;
int sock = -1;
snamelen = strlen(sname);
if (snamelen > 255)
return -EINVAL;
result = make_local_socket(sockname);
if (result < 0) {
SNDERR("server for socket %s is not running", sockname);
goto _err;
}
sock = result;
reqlen = sizeof(*req) + snamelen;
req = alloca(reqlen);
memcpy(req->name, sname, snamelen);
req->dev_type = SND_DEV_TYPE_PCM;
req->transport_type = SND_TRANSPORT_TYPE_SHM;
req->stream = stream;
req->mode = mode;
req->namelen = snamelen;
err = write(sock, req, reqlen);
if (err < 0) {
SYSERR("write error");
result = -errno;
goto _err;
}
if ((size_t) err != reqlen) {
SNDERR("write size error");
result = -EINVAL;
goto _err;
}
err = read(sock, &ans, sizeof(ans));
if (err < 0) {
SYSERR("read error");
result = -errno;
goto _err;
}
if (err != sizeof(ans)) {
SNDERR("read size error");
result = -EINVAL;
goto _err;
}
result = ans.result;
if (result < 0)
goto _err;
ctrl = shmat(ans.cookie, 0, 0);
if (!ctrl) {
SYSERR("shmat error");
result = -errno;
goto _err;
}
shm = calloc(1, sizeof(snd_pcm_shm_t));
if (!shm) {
result = -ENOMEM;
goto _err;
}
shm->socket = sock;
shm->ctrl = ctrl;
err = snd_pcm_new(&pcm, SND_PCM_TYPE_SHM, name, stream, mode);
if (err < 0) {
result = err;
goto _err;
}
pcm->mmap_rw = 1;
pcm->ops = &snd_pcm_shm_ops;
pcm->fast_ops = &snd_pcm_shm_fast_ops;
pcm->private_data = shm;
err = snd_pcm_shm_poll_descriptor(pcm);
if (err < 0) {
snd_pcm_close(pcm);
return err;
}
pcm->poll_fd = err;
pcm->poll_events = stream == SND_PCM_STREAM_PLAYBACK ? POLLOUT : POLLIN;
snd_pcm_set_hw_ptr(pcm, &ctrl->hw.ptr, -1, 0);
snd_pcm_set_appl_ptr(pcm, &ctrl->appl.ptr, -1, 0);
*pcmp = pcm;
return 0;
_err:
close(sock);
if (ctrl)
shmdt(ctrl);
free(shm);
return result;
}
/*! \page pcm_plugins
\section pcm_plugins_shm Plugin: shm
This plugin communicates with aserver via shared memory. It is a raw
communication without any conversions, but it can be expected worse
performance.
\code
pcm.name {
type shm # Shared memory PCM
server STR # Server name
pcm STR # PCM name
}
\endcode
\subsection pcm_plugins_shm_funcref Function reference
<UL>
<LI>snd_pcm_shm_open()
<LI>_snd_pcm_shm_open()
</UL>
*/
/**
* \brief Creates a new shm PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param root Root configuration node
* \param conf Configuration node with hw PCM description
* \param stream PCM Stream
* \param mode PCM Mode
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int _snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name,
snd_config_t *root, snd_config_t *conf,
snd_pcm_stream_t stream, int mode)
{
snd_config_iterator_t i, next;
const char *server = NULL;
const char *pcm_name = NULL;
snd_config_t *sconfig;
const char *sockname = NULL;
long port = -1;
int err;
snd_config_for_each(i, next, conf) {
snd_config_t *n = snd_config_iterator_entry(i);
const char *id;
if (snd_config_get_id(n, &id) < 0)
continue;
if (snd_pcm_conf_generic_id(id))
continue;
if (strcmp(id, "server") == 0) {
err = snd_config_get_string(n, &server);
if (err < 0) {
SNDERR("Invalid type for %s", id);
return -EINVAL;
}
continue;
}
if (strcmp(id, "pcm") == 0) {
err = snd_config_get_string(n, &pcm_name);
if (err < 0) {
SNDERR("Invalid type for %s", id);
return -EINVAL;
}
continue;
}
SNDERR("Unknown field %s", id);
return -EINVAL;
}
if (!pcm_name) {
SNDERR("pcm is not defined");
return -EINVAL;
}
if (!server) {
SNDERR("server is not defined");
return -EINVAL;
}
err = snd_config_search_definition(root, "server", server, &sconfig);
if (err < 0) {
SNDERR("Unknown server %s", server);
return -EINVAL;
}
if (snd_config_get_type(sconfig) != SND_CONFIG_TYPE_COMPOUND) {
SNDERR("Invalid type for server %s definition", server);
goto _err;
}
snd_config_for_each(i, next, sconfig) {
snd_config_t *n = snd_config_iterator_entry(i);
const char *id;
if (snd_config_get_id(n, &id) < 0)
continue;
if (strcmp(id, "comment") == 0)
continue;
if (strcmp(id, "host") == 0)
continue;
if (strcmp(id, "socket") == 0) {
err = snd_config_get_string(n, &sockname);
if (err < 0) {
SNDERR("Invalid type for %s", id);
goto _err;
}
continue;
}
if (strcmp(id, "port") == 0) {
err = snd_config_get_integer(n, &port);
if (err < 0) {
SNDERR("Invalid type for %s", id);
goto _err;
}
continue;
}
SNDERR("Unknown field %s", id);
_err:
err = -EINVAL;
goto __error;
}
if (!sockname) {
SNDERR("socket is not defined");
goto _err;
}
err = snd_pcm_shm_open(pcmp, name, sockname, pcm_name, stream, mode);
__error:
snd_config_delete(sconfig);
return err;
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_shm_open, SND_PCM_DLSYM_VERSION);
#endif
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