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PCM: Add string conversion helper functions for chmap

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Added a few helper functions between chmap and string.
  snd_pcm_chmap_type_name() -- a string of the given chmap type
  snd_pcm_chmap_name() -- a string of the given channel position
  snd_pcm_chmap_print() -- print channel map on the given buffer
  snd_pcm_chmap_from_string() -- get a channel position from string
  snd_pcm_parse_string() -- parse the whole channel map from string

Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2012-09-10 18:07:36 +02:00
parent 6950a1030c
commit b4c64e815a
3 changed files with 160 additions and 57 deletions
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142
src/pcm/pcm.c
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@ -633,6 +633,7 @@ playback devices.
#include <malloc.h>
#include <stdarg.h>
#include <signal.h>
#include <ctype.h>
#include <sys/poll.h>
#include <sys/shm.h>
#include <sys/mman.h>
@ -7356,6 +7357,147 @@ int snd_pcm_set_chmap(snd_pcm_t *pcm, const snd_pcm_chmap_t *map)
return pcm->ops->set_chmap(pcm, map);
}
/*
*/
#define _NAME(n) [SND_CHMAP_TYPE_##n] = #n
static const char *chmap_type_names[SND_CHMAP_TYPE_LAST + 1] = {
_NAME(NONE), _NAME(FIXED), _NAME(VAR), _NAME(PAIRED),
};
#undef _NAME
const char *snd_pcm_chmap_type_name(enum snd_pcm_chmap_type val)
{
if (val <= SND_CHMAP_TYPE_LAST)
return chmap_type_names[val];
else
return NULL;
}
#define _NAME(n) [SND_CHMAP_##n] = #n
static const char *chmap_names[SND_CHMAP_LAST + 1] = {
_NAME(UNKNOWN),
_NAME(FL), _NAME(FR),
_NAME(RL), _NAME(RR),
_NAME(FC), _NAME(LFE),
_NAME(SL), _NAME(SR),
_NAME(RC), _NAME(FLC), _NAME(FRC), _NAME(RLC), _NAME(RRC),
_NAME(FLW), _NAME(FRW),
_NAME(FLH), _NAME(FCH), _NAME(FRH), _NAME(TC),
_NAME(NA),
};
#undef _NAME
const char *snd_pcm_chmap_name(enum snd_pcm_chmap_position val)
{
if (val <= SND_CHMAP_LAST)
return chmap_names[val];
else
return NULL;
}
int snd_pcm_chmap_print(const snd_pcm_chmap_t *map, size_t maxlen, char *buf)
{
unsigned int i, len = 0;
for (i = 0; i < map->channels; i++) {
unsigned int p = map->pos[i] & SND_CHMAP_POSITION_MASK;
if (i > 0) {
len += snprintf(buf + len, maxlen - len, " ");
if (len >= maxlen)
return -ENOMEM;
}
if (map->pos[i] & SND_CHMAP_DRIVER_SPEC)
len += snprintf(buf + len, maxlen, "%d", p);
else {
const char *name = chmap_names[p];
if (name)
len += snprintf(buf + len, maxlen - len,
"%s", name);
else
len += snprintf(buf + len, maxlen - len,
"Ch%d", p);
}
if (len >= maxlen)
return -ENOMEM;
if (map->pos[i] & SND_CHMAP_PHASE_INVERSE) {
len += snprintf(buf + len, maxlen - len, "[INV]");
if (len >= maxlen)
return -ENOMEM;
}
}
return len;
}
static int str_to_chmap(const char *str, int len)
{
int val;
if (isdigit(*str)) {
val = atoi(str);
if (val < 0)
return -1;
return val | SND_CHMAP_DRIVER_SPEC;
} else if (str[0] == 'C' && str[1] == 'h') {
val = atoi(str + 2);
if (val < 0)
return -1;
return val;
} else {
for (val = 0; val <= SND_CHMAP_LAST; val++) {
if (!strncmp(str, chmap_names[val], len))
return val;
}
return -1;
}
}
unsigned int snd_pcm_chmap_from_string(const char *str)
{
return str_to_chmap(str, strlen(str));
}
snd_pcm_chmap_t *snd_pcm_chmap_parse_string(const char *str)
{
int i, ch = 0;
int tmp_map[64];
snd_pcm_chmap_t *map;
for (;;) {
const char *p;
int len, val;
if (ch >= (int)(sizeof(tmp_map) / sizeof(tmp_map[0])))
return NULL;
for (p = str; *p && isalnum(*p); p++)
;
len = p - str;
if (!len)
return NULL;
val = str_to_chmap(str, len);
if (val < 0)
return NULL;
str += len;
if (*str == '[') {
if (!strncmp(str, "[INV]", 5)) {
val |= SND_CHMAP_PHASE_INVERSE;
str += 5;
}
}
tmp_map[ch] = val;
ch++;
for (; *str && !isalnum(*str); str++)
;
if (!*str)
break;
}
map = malloc(sizeof(*map) + ch * sizeof(int));
if (!map)
return NULL;
map->channels = ch;
for (i = 0; i < ch; i++)
map->pos[i] = tmp_map[i];
return map;
}
/*
* basic helpers