Files
UltraGrid/src/alsa_common.h
2019-11-09 17:20:37 +01:00

235 lines
9.1 KiB
C

/**
* @file alsa_common.h
* @author Martin Pulec <pulec@cesnet.cz>
*/
/*
* Copyright (c) 2015-2019 CESNET, z. s. p. o.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, is permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of CESNET nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef ALSA_COMMON_H
#define ALSA_COMMON_H
#include <alsa/asoundlib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "debug.h"
#include "utils/color_out.h"
#include "types.h"
static inline void audio_alsa_probe(struct device_info **available_devices,
int *count,
const char **whitelist,
size_t whitelist_size)
{
void **hints;
snd_device_name_hint(-1, "pcm", &hints);
size_t device_count = 0;
for (void **it = hints; *it != NULL; it++) device_count++;
*available_devices = calloc(device_count + 1 , sizeof(struct device_info));
strcpy((*available_devices)[0].id, "alsa");
strcpy((*available_devices)[0].name, "Default Linux audio");
*count = 1;
for(void **it = hints; *it != NULL; it++){
char *id = snd_device_name_get_hint(*it, "NAME");
bool whitelisted = false;
for(size_t i = 0; i < whitelist_size; i++){
if(strstr(id, whitelist[i])){
whitelisted = true;
break;
}
}
if(!whitelisted && whitelist_size > 0) {
free(id);
continue;
}
strcpy((*available_devices)[*count].id, "alsa:");
strncat((*available_devices)[*count].id, id,
sizeof (*available_devices)[*count].id -
strlen((*available_devices)[*count].id) - 1);
free(id);
char *name = snd_device_name_get_hint(*it, "DESC");
char *tok = name;
while(tok){
char *newline = strchr(tok, '\n');
if(newline){
*newline = '\0';
strncat((*available_devices)[*count].name, tok,
sizeof (*available_devices)[*count].name -
strlen((*available_devices)[*count].name) - 1);
strncat((*available_devices)[*count].name, " - ",
sizeof (*available_devices)[*count].name -
strlen((*available_devices)[*count].name) - 1);
tok = newline + 1;
} else {
strncat((*available_devices)[*count].name, tok,
sizeof (*available_devices)[*count].name -
strlen((*available_devices)[*count].name) - 1);
tok = NULL;
}
}
free(name);
(*count)++;
}
snd_device_name_free_hint(hints);
}
static inline void audio_alsa_help(void)
{
struct device_info *available_devices;
int count;
audio_alsa_probe(&available_devices, &count, NULL, 0);
strcpy(available_devices[0].id, "alsa");
strcpy(available_devices[0].name, "default ALSA device (same as \"alsa:default\")");
for(int i = 0; i < count; i++){
const char * const id = available_devices[i].id;
color_out(COLOR_OUT_BOLD, "\t%s", id);
for (int j = 0; j < 30 - (int) strlen(id); ++j) putchar(' ');
printf(": %s\n", available_devices[i].name);
}
free(available_devices);
}
static const snd_pcm_format_t bps_to_snd_fmts[] = {
[0] = SND_PCM_FORMAT_UNKNOWN,
[1] = SND_PCM_FORMAT_U8,
[2] = SND_PCM_FORMAT_S16_LE,
[3] = SND_PCM_FORMAT_S24_3LE,
[4] = SND_PCM_FORMAT_S32_LE,
};
/**
* Finds equal or nearest higher sample rate that device supports. If none exist, pick highest
* lower value.
*
* @returns sample rate, 0 if none was found
*/
static int get_rate_near(snd_pcm_t *handle, snd_pcm_hw_params_t *params, unsigned int approx_val) {
int ret = 0;
int dir = 0;
int rc;
unsigned int rate = approx_val;
// try exact sample rate
rc = snd_pcm_hw_params_set_rate_min(handle, params, &rate, &dir);
if (rc != 0) {
dir = 1;
// or higher
rc = snd_pcm_hw_params_set_rate_min(handle, params, &rate, &dir);
}
if (rc == 0) {
// read the rate
rc = snd_pcm_hw_params_get_rate_min(params, &rate, NULL);
if (rc == 0) {
ret = rate;
}
// restore configuration space
rate = 0;
dir = 1;
rc = snd_pcm_hw_params_set_rate_min(handle, params, &rate, &dir);
assert(rc == 0);
}
// we did not succeed, try lower sample rate
if (ret == 0) {
unsigned int rate = approx_val;
dir = 0;
unsigned int orig_max;
rc = snd_pcm_hw_params_get_rate_max(params, &orig_max, NULL);
assert(rc == 0);
rc = snd_pcm_hw_params_set_rate_max(handle, params, &rate, &dir);
if (rc != 0) {
dir = -1;
rc = snd_pcm_hw_params_set_rate_max(handle, params, &rate, &dir);
}
if (rc == 0) {
rc = snd_pcm_hw_params_get_rate_max(params, &rate, NULL);
if (rc == 0) {
ret = rate;
}
// restore configuration space
dir = 0;
rc = snd_pcm_hw_params_set_rate_max(handle, params, &orig_max, &dir);
assert(rc == 0);
}
}
return ret;
}
static void print_alsa_device_info(snd_pcm_t *handle, const char *module_name) {
snd_pcm_info_t *info;
snd_pcm_info_alloca(&info);
if (snd_pcm_info(handle, info) == 0) {
log_msg(LOG_LEVEL_NOTICE, "%sUsing device: %s\n",
module_name, snd_pcm_info_get_name(info));
}
}
static const char *alsa_get_pcm_state_name(snd_pcm_state_t state) __attribute__((unused));
static const char *alsa_get_pcm_state_name(snd_pcm_state_t state) {
switch (state) {
case SND_PCM_STATE_OPEN:
return "Open";
case SND_PCM_STATE_SETUP:
return "Setup installed";
case SND_PCM_STATE_PREPARED:
return "Ready to start";
case SND_PCM_STATE_RUNNING:
return "Running";
case SND_PCM_STATE_XRUN:
return "Stopped: underrun (playback) or overrun (capture) detected";
case SND_PCM_STATE_DRAINING:
return "Draining: running (playback) or stopped (capture)";
case SND_PCM_STATE_PAUSED:
return "Paused";
case SND_PCM_STATE_SUSPENDED:
return "Hardware is suspended";
case SND_PCM_STATE_DISCONNECTED:
return "Hardware is disconnected";
default:
return "(unknown)";
}
}
#endif // defined ALSA_COMMON_H