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#include <stdio.h>
#include "jpeg_bits.h"
/* FIXME */
#define TRUE 1
#define FALSE 0
int jpeg_bits_error (JpegBits *bits)
{
return bits->error;
}
int jpeg_bits_get_u8 (JpegBits *bits)
{
if (bits->ptr < bits->end) {
return *bits->ptr++;
}
bits->error = TRUE;
return 0;
}
void jpeg_bits_skip (JpegBits *bits, int n)
{
bits->ptr += n;
if (bits->ptr > bits->end) {
bits->error = TRUE;
bits->ptr = bits->end;
}
}
int jpeg_bits_get_u16_be (JpegBits *bits)
{
int x;
x = jpeg_bits_get_u8 (bits) << 8;
x |= jpeg_bits_get_u8 (bits);
return x;
}
int jpeg_bits_available (JpegBits *bits)
{
return bits->end - bits->ptr;
}
int bits_needbits(JpegBits *b, int n_bytes)
{
if(b->ptr==NULL)return 1;
if(b->ptr + n_bytes > b->end)return 1;
return 0;
}
int getbit(JpegBits *b)
{
int r;
r = ((*b->ptr)>>(7-b->idx))&1;
b->idx++;
if(b->idx>=8){
b->ptr++;
b->idx = 0;
}
return r;
}
unsigned int getbits(JpegBits *b, int n)
{
unsigned long r = 0;
int i;
for(i=0;i<n;i++){
r <<=1;
r |= getbit(b);
}
return r;
}
unsigned int peekbits(JpegBits *b, int n)
{
JpegBits tmp = *b;
return getbits(&tmp, n);
}
int getsbits(JpegBits *b, int n)
{
unsigned long r = 0;
int i;
if(n==0)return 0;
r = -getbit(b);
for(i=1;i<n;i++){
r <<=1;
r |= getbit(b);
}
return r;
}
unsigned int peek_u8(JpegBits *b)
{
return *b->ptr;
}
unsigned int get_u8(JpegBits *b)
{
return *b->ptr++;
}
unsigned int get_u16(JpegBits *b)
{
unsigned int r;
r = b->ptr[0] | (b->ptr[1]<<8);
b->ptr+=2;
return r;
}
unsigned int get_be_u16(JpegBits *b)
{
unsigned int r;
r = (b->ptr[0]<<8) | b->ptr[1];
b->ptr+=2;
return r;
}
unsigned int get_u32(JpegBits *b)
{
unsigned int r;
r = b->ptr[0] | (b->ptr[1]<<8) | (b->ptr[2]<<16) | (b->ptr[3]<<24);
b->ptr+=4;
return r;
}
void syncbits(JpegBits *b)
{
if(b->idx){
b->ptr++;
b->idx=0;
}
}
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