ref: fc08d0a6d63a5453a8928bd5f77e30cf73f13073
dir: /libentcode/entenc.c/
#include <stdlib.h> #include <string.h> #include "entenc.h" #define EC_BUFFER_INCREMENT (256) void ec_byte_writeinit(ec_byte_buffer *_b){ _b->ptr=_b->buf=malloc(EC_BUFFER_INCREMENT); _b->storage=EC_BUFFER_INCREMENT; } void ec_byte_writetrunc(ec_byte_buffer *_b,long _bytes){ _b->ptr=_b->buf+_bytes; } void ec_byte_write1(ec_byte_buffer *_b,unsigned _value){ ptrdiff_t endbyte; endbyte=_b->ptr-_b->buf; if(endbyte>=_b->storage){ _b->buf=realloc(_b->buf,_b->storage+EC_BUFFER_INCREMENT); _b->storage+=EC_BUFFER_INCREMENT; _b->ptr=_b->buf+endbyte; } *(_b->ptr++)=(unsigned char)_value; } void ec_byte_write4(ec_byte_buffer *_b,ec_uint32 _value){ ptrdiff_t endbyte; endbyte=_b->ptr-_b->buf; if(endbyte+4>_b->storage){ _b->buf=realloc(_b->buf,_b->storage+EC_BUFFER_INCREMENT); _b->storage+=EC_BUFFER_INCREMENT; _b->ptr=_b->buf+endbyte; } *(_b->ptr++)=(unsigned char)_value; _value>>=8; *(_b->ptr++)=(unsigned char)_value; _value>>=8; *(_b->ptr++)=(unsigned char)_value; _value>>=8; *(_b->ptr++)=(unsigned char)_value; } void ec_byte_writecopy(ec_byte_buffer *_b,void *_source,long _bytes){ ptrdiff_t endbyte; endbyte=_b->ptr-_b->buf; if(endbyte+_bytes>_b->storage){ _b->storage=endbyte+_bytes+EC_BUFFER_INCREMENT; _b->buf=realloc(_b->buf,_b->storage); _b->ptr=_b->buf+endbyte; } memmove(_b->ptr,_source,_bytes); _b->ptr+=_bytes; } void ec_byte_writeclear(ec_byte_buffer *_b){ free(_b->buf); } void ec_enc_bits(ec_enc *_this,ec_uint32 _fl,int _ftb){ unsigned fl; unsigned ft; while(_ftb>EC_UNIT_BITS){ _ftb-=EC_UNIT_BITS; fl=(unsigned)(_fl>>_ftb)&EC_UNIT_MASK; ec_encode(_this,fl,fl+1,EC_UNIT_MASK+1); } ft=1<<_ftb; fl=_fl&ft-1; ec_encode(_this,fl,fl+1,ft); } void ec_enc_uint(ec_enc *_this,ec_uint32 _fl,ec_uint32 _ft){ ec_uint32 mask; ec_uint32 ft; unsigned fl; int ftb; _ft--; ftb=EC_ILOG(_ft); while(ftb>EC_UNIT_BITS){ ftb-=EC_UNIT_BITS; ft=(_ft>>ftb)+1; fl=(unsigned)(_fl>>ftb); ec_encode(_this,fl,fl+1,ft); if(fl<ft-1){ ec_enc_bits(_this,_fl,ftb); return; } mask=((ec_uint32)1<<ftb)-1; _fl=_fl&mask; _ft=_ft&mask; } ec_encode(_this,_fl,_fl+1,_ft+1); }