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Fix endianess with dmix plugin

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Allow different endianess with the generic dmix code, mainly for
big-endian architectures.
This commit is contained in:
Takashi Iwai 2005-09-19 12:37:08 +00:00
parent 148c2b8e7c
commit 5bf3b31cf1
5 changed files with 177 additions and 12 deletions
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144
src/pcm/pcm_dmix_generic.c
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@ -47,6 +47,7 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
#define IS_CONCURRENT 0 /* no race check */
#endif
#if IS_CONCURRENT
static void mix_areas1(unsigned int size,
volatile signed short *dst, signed short *src,
volatile signed int *sum, size_t dst_step,
@ -114,3 +115,146 @@ static void mix_select_callbacks(snd_pcm_direct_t *dmix)
dmix->u.dmix.mix_areas1 = mix_areas1;
dmix->u.dmix.mix_areas2 = mix_areas2;
}
#else
/* non-concurrent version, supporting both endians */
static unsigned long long dmix_supported_format =
(1ULL << SND_PCM_FORMAT_S16_LE) | (1ULL << SND_PCM_FORMAT_S32_LE) |
(1ULL << SND_PCM_FORMAT_S16_BE) | (1ULL << SND_PCM_FORMAT_S32_BE);
#include <byteswap.h>
static void mix_areas1_native(unsigned int size,
volatile signed short *dst, signed short *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
register signed int sample;
for (;;) {
sample = *src;
if (! *dst) {
*sum = sample;
*dst = *src;
} else {
sample += *sum;
*sum = sample;
if (sample > 0x7fff)
sample = 0x7fff;
else if (sample < -0x8000)
sample = -0x8000;
*dst = sample;
}
if (!--size)
return;
src = (signed short *) ((char *)src + src_step);
dst = (signed short *) ((char *)dst + dst_step);
sum = (signed int *) ((char *)sum + sum_step);
}
}
static void mix_areas2_native(unsigned int size,
volatile signed int *dst, signed int *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
register signed int sample;
for (;;) {
sample = *src / 256;
if (! *dst) {
*sum = sample;
*dst = *src;
} else {
sample += *sum;
*sum = sample;
if (sample > 0x7fffff)
sample = 0x7fffffff;
else if (sample < -0x800000)
sample = -0x80000000;
else
sample *= 256;
*dst = sample;
}
if (!--size)
return;
src = (signed int *) ((char *)src + src_step);
dst = (signed int *) ((char *)dst + dst_step);
sum = (signed int *) ((char *)sum + sum_step);
}
}
static void mix_areas1_swap(unsigned int size,
volatile signed short *dst, signed short *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
register signed int sample;
for (;;) {
sample = bswap_16(*src);
if (! *dst) {
*sum = sample;
*dst = *src;
} else {
sample += *sum;
*sum = sample;
if (sample > 0x7fff)
sample = 0x7fff;
else if (sample < -0x8000)
sample = -0x8000;
*dst = bswap_16((signed short)sample);
}
if (!--size)
return;
src = (signed short *) ((char *)src + src_step);
dst = (signed short *) ((char *)dst + dst_step);
sum = (signed int *) ((char *)sum + sum_step);
}
}
static void mix_areas2_swap(unsigned int size,
volatile signed int *dst, signed int *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
register signed int sample;
for (;;) {
sample = bswap_32(*src) / 256;
if (! *dst) {
*sum = sample;
*dst = *src;
} else {
sample += *sum;
*sum = sample;
if (sample > 0x7fffff)
sample = 0x7fffffff;
else if (sample < -0x800000)
sample = -0x80000000;
else
sample *= 256;
*dst = bswap_32(sample);
}
if (!--size)
return;
src = (signed int *) ((char *)src + src_step);
dst = (signed int *) ((char *)dst + dst_step);
sum = (signed int *) ((char *)sum + sum_step);
}
}
static void mix_select_callbacks(snd_pcm_direct_t *dmix)
{
if (snd_pcm_format_cpu_endian(dmix->shmptr->s.format)) {
dmix->u.dmix.mix_areas1 = mix_areas1_native;
dmix->u.dmix.mix_areas2 = mix_areas2_native;
} else {
dmix->u.dmix.mix_areas1 = mix_areas1_swap;
dmix->u.dmix.mix_areas2 = mix_areas2_swap;
}
}
#endif