vgmstream/src/util.c
2020-06-04 23:11:38 +02:00

138 lines
3.7 KiB
C

#include <string.h>
#include "util.h"
#include "streamtypes.h"
const char * filename_extension(const char * pathname) {
const char * filename;
const char * extension;
/* favor strrchr (optimized/aligned) rather than homemade loops */
/* find possible separator first to avoid misdetecting folders with dots + extensionless files
* (allow both slashes as plugin could pass normalized '/') */
filename = strrchr(pathname, '/');
if (filename != NULL)
filename++; /* skip separator */
else {
filename = strrchr(pathname, '\\');
if (filename != NULL)
filename++; /* skip separator */
else
filename = pathname; /* pathname has no separators (single filename) */
}
extension = strrchr(filename,'.');
if (extension != NULL)
extension++; /* skip dot */
else
extension = filename + strlen(filename); /* point to null (empty "" string for extensionless files) */
return extension;
}
/* unused */
/*
void interleave_channel(sample_t * outbuffer, sample_t * inbuffer, int32_t sample_count, int channel_count, int channel_number) {
int32_t insample,outsample;
if (channel_count==1) {
memcpy(outbuffer,inbuffer,sizeof(sample)*sample_count);
return;
}
for (insample=0,outsample=channel_number;insample<sample_count;insample++,outsample+=channel_count) {
outbuffer[outsample]=inbuffer[insample];
}
}
*/
/* failed attempt at interleave in place */
/*
void interleave_stereo(sample_t * buffer, int32_t sample_count) {
int32_t tomove, belongs;
sample_t moving,temp;
tomove = sample_count;
moving = buffer[tomove];
do {
if (tomove<sample_count)
belongs = tomove*2;
else
belongs = (tomove-sample_count)*2+1;
temp = buffer[belongs];
buffer[belongs] = moving;
moving = temp;
tomove = belongs;
} while (tomove != sample_count);
}
*/
void put_8bit(uint8_t * buf, int8_t i) {
buf[0] = i;
}
void put_16bitLE(uint8_t * buf, int16_t i) {
buf[0] = (i & 0xFF);
buf[1] = i >> 8;
}
void put_32bitLE(uint8_t * buf, int32_t i) {
buf[0] = (uint8_t)(i & 0xFF);
buf[1] = (uint8_t)((i >> 8) & 0xFF);
buf[2] = (uint8_t)((i >> 16) & 0xFF);
buf[3] = (uint8_t)((i >> 24) & 0xFF);
}
void put_16bitBE(uint8_t * buf, int16_t i) {
buf[0] = i >> 8;
buf[1] = (i & 0xFF);
}
void put_32bitBE(uint8_t * buf, int32_t i) {
buf[0] = (uint8_t)((i >> 24) & 0xFF);
buf[1] = (uint8_t)((i >> 16) & 0xFF);
buf[2] = (uint8_t)((i >> 8) & 0xFF);
buf[3] = (uint8_t)(i & 0xFF);
}
int round10(int val) {
int round_val = val % 10;
if (round_val < 5) /* half-down rounding */
return val - round_val;
else
return val + (10 - round_val);
}
void swap_samples_le(sample_t *buf, int count) {
/* Windows can't be BE... I think */
#if !defined(_WIN32)
#if !defined(__BYTE_ORDER__) || __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
int i;
for (i = 0; i < count; i++) {
/* 16b sample in memory: aabb where aa=MSB, bb=LSB */
uint8_t b0 = buf[i] & 0xff;
uint8_t b1 = buf[i] >> 8;
uint8_t *p = (uint8_t*)&(buf[i]);
/* 16b sample in buffer: bbaa where bb=LSB, aa=MSB */
p[0] = b0;
p[1] = b1;
/* when endianness is LE, buffer has bbaa already so this function can be skipped */
}
#endif
#endif
}
/* length is maximum length of dst. dst will always be null-terminated if
* length > 0 */
void concatn(int length, char * dst, const char * src) {
int i,j;
if (length <= 0) return;
for (i=0;i<length-1 && dst[i];i++); /* find end of dst */
for (j=0;i<length-1 && src[j];i++,j++)
dst[i]=src[j];
dst[i]='\0';
}