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Code clean-up for crc.c, lfg.c, log.c, random_see.d, rational.c and tree.c.

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Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
This commit is contained in:
Yordan Makariev
2011-12-03 20:25:57 +02:00
committed by Ronald S. Bultje
parent 4a59eca97a
commit 425b45d4b0
6 changed files with 284 additions and 233 deletions
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73
libavutil/crc.c
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@@ -56,32 +56,34 @@ static AVCRC av_crc_table[AV_CRC_MAX][257];
* @param ctx_size size of ctx in bytes
* @return <0 on failure
*/
int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size){
int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size)
{
unsigned i, j;
uint32_t c;
if (bits < 8 || bits > 32 || poly >= (1LL<<bits))
if (bits < 8 || bits > 32 || poly >= (1LL << bits))
return -1;
if (ctx_size != sizeof(AVCRC)*257 && ctx_size != sizeof(AVCRC)*1024)
if (ctx_size != sizeof(AVCRC) * 257 && ctx_size != sizeof(AVCRC) * 1024)
return -1;
for (i = 0; i < 256; i++) {
if (le) {
for (c = i, j = 0; j < 8; j++)
c = (c>>1)^(poly & (-(c&1)));
c = (c >> 1) ^ (poly & (-(c & 1)));
ctx[i] = c;
} else {
for (c = i << 24, j = 0; j < 8; j++)
c = (c<<1) ^ ((poly<<(32-bits)) & (((int32_t)c)>>31) );
c = (c << 1) ^ ((poly << (32 - bits)) & (((int32_t) c) >> 31));
ctx[i] = av_bswap32(c);
}
}
ctx[256]=1;
ctx[256] = 1;
#if !CONFIG_SMALL
if(ctx_size >= sizeof(AVCRC)*1024)
if (ctx_size >= sizeof(AVCRC) * 1024)
for (i = 0; i < 256; i++)
for(j=0; j<3; j++)
ctx[256*(j+1) + i]= (ctx[256*j + i]>>8) ^ ctx[ ctx[256*j + i]&0xFF ];
for (j = 0; j < 3; j++)
ctx[256 *(j + 1) + i] =
(ctx[256 * j + i] >> 8) ^ ctx[ctx[256 * j + i] & 0xFF];
#endif
return 0;
@@ -92,9 +94,10 @@ int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size){
* @param crc_id ID of a standard CRC
* @return a pointer to the CRC table or NULL on failure
*/
const AVCRC *av_crc_get_table(AVCRCId crc_id){
const AVCRC *av_crc_get_table(AVCRCId crc_id)
{
#if !CONFIG_HARDCODED_TABLES
if (!av_crc_table[crc_id][FF_ARRAY_ELEMS(av_crc_table[crc_id])-1])
if (!av_crc_table[crc_id][FF_ARRAY_ELEMS(av_crc_table[crc_id]) - 1])
if (av_crc_init(av_crc_table[crc_id],
av_crc_table_params[crc_id].le,
av_crc_table_params[crc_id].bits,
@@ -112,46 +115,50 @@ const AVCRC *av_crc_get_table(AVCRCId crc_id){
*
* @see av_crc_init() "le" parameter
*/
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length){
const uint8_t *end= buffer+length;
uint32_t av_crc(const AVCRC *ctx, uint32_t crc,
const uint8_t *buffer, size_t length)
{
const uint8_t *end = buffer + length;
#if !CONFIG_SMALL
if(!ctx[256]) {
while(((intptr_t) buffer & 3) && buffer < end)
crc = ctx[((uint8_t)crc) ^ *buffer++] ^ (crc >> 8);
if (!ctx[256]) {
while (((intptr_t) buffer & 3) && buffer < end)
crc = ctx[((uint8_t) crc) ^ *buffer++] ^ (crc >> 8);
while(buffer<end-3){
crc ^= av_le2ne32(*(const uint32_t*)buffer); buffer+=4;
crc = ctx[3*256 + ( crc &0xFF)]
^ctx[2*256 + ((crc>>8 )&0xFF)]
^ctx[1*256 + ((crc>>16)&0xFF)]
^ctx[0*256 + ((crc>>24) )];
while (buffer < end - 3) {
crc ^= av_le2ne32(*(const uint32_t *) buffer); buffer += 4;
crc = ctx[3 * 256 + ( crc & 0xFF)] ^
ctx[2 * 256 + ((crc >> 8 ) & 0xFF)] ^
ctx[1 * 256 + ((crc >> 16) & 0xFF)] ^
ctx[0 * 256 + ((crc >> 24) )];
}
}
#endif
while(buffer<end)
crc = ctx[((uint8_t)crc) ^ *buffer++] ^ (crc >> 8);
while (buffer < end)
crc = ctx[((uint8_t) crc) ^ *buffer++] ^ (crc >> 8);
return crc;
}
#ifdef TEST
#undef printf
int main(void){
int main(void)
{
uint8_t buf[1999];
int i;
int p[4][3]={{AV_CRC_32_IEEE_LE, 0xEDB88320, 0x3D5CDD04},
{AV_CRC_32_IEEE , 0x04C11DB7, 0xC0F5BAE0},
{AV_CRC_16_ANSI , 0x8005, 0x1FBB },
{AV_CRC_8_ATM , 0x07, 0xE3 },};
int p[4][3] = { { AV_CRC_32_IEEE_LE, 0xEDB88320, 0x3D5CDD04 },
{ AV_CRC_32_IEEE , 0x04C11DB7, 0xC0F5BAE0 },
{ AV_CRC_16_ANSI , 0x8005 , 0x1FBB },
{ AV_CRC_8_ATM , 0x07 , 0xE3 }
};
const AVCRC *ctx;
for(i=0; i<sizeof(buf); i++)
buf[i]= i+i*i;
for (i = 0; i < sizeof(buf); i++)
buf[i] = i + i * i;
for(i=0; i<4; i++){
for (i = 0; i < 4; i++) {
ctx = av_crc_get_table(p[i][0]);
printf("crc %08X =%X\n", p[i][1], av_crc(ctx, 0, buf, sizeof(buf)));
printf("crc %08X = %X\n", p[i][1], av_crc(ctx, 0, buf, sizeof(buf)));
}
return 0;
}