/*
* qrencode - QR Code encoder
*
* Binary sequence class.
* Copyright (C) 2006-2014 Kentaro Fukuchi <kentaro@fukuchi.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "bitstream.h"
#define DEFAULT_BUFSIZE (128)
BitStream *BitStream_new(void)
{
BitStream *bstream;
bstream = (BitStream *)malloc(sizeof(BitStream));
if(bstream == NULL) return NULL;
bstream->length = 0;
bstream->data = (unsigned char *)malloc(DEFAULT_BUFSIZE);
if(bstream->data == NULL) {
free(bstream);
return NULL;
}
bstream->datasize = DEFAULT_BUFSIZE;
return bstream;
}
static int BitStream_expand(BitStream *bstream)
{
unsigned char *data;
data = (unsigned char *)realloc(bstream->data, bstream->datasize * 2);
if(data == NULL) {
return -1;
}
bstream->data = data;
bstream->datasize *= 2;
return 0;
}
static void BitStream_writeNum(unsigned char *dest, int bits, unsigned int num)
{
unsigned int mask;
int i;
unsigned char *p;
p = dest;
mask = 1 << (bits - 1);
for(i=0; i<bits; i++) {
if(num & mask) {
*p = 1;
} else {
*p = 0;
}
p++;
mask = mask >> 1;
}
}
static void BitStream_writeBytes(unsigned char *dest, int size, unsigned char *data)
{
unsigned char mask;
int i, j;
unsigned char *p;
p = dest;
for(i=0; i<size; i++) {
mask = 0x80;
for(j=0; j<8; j++) {
if(data[i] & mask) {
*p = 1;
} else {
*p = 0;
}
p++;
mask = mask >> 1;
}
}
}
int BitStream_append(BitStream *bstream, BitStream *arg)
{
int ret;
if(arg == NULL) {
return -1;
}
if(arg->length == 0) {
return 0;
}
while(bstream->length + arg->length > bstream->datasize) {
ret = BitStream_expand(bstream);
if(ret < 0) return ret;
}
memcpy(bstream->data + bstream->length, arg->data, arg->length);
bstream->length += arg->length;
return 0;
}
int BitStream_appendNum(BitStream *bstream, int bits, unsigned int num)
{
int ret;
if(bits == 0) return 0;
while(bstream->datasize - bstream->length < bits) {
ret = BitStream_expand(bstream);
if(ret < 0) return ret;
}
BitStream_writeNum(bstream->data + bstream->length, bits, num);
bstream->length += bits;
return 0;
}
int BitStream_appendBytes(BitStream *bstream, int size, unsigned char *data)
{
int ret;
if(size == 0) return 0;
while(bstream->datasize - bstream->length < size * 8) {
ret = BitStream_expand(bstream);
if(ret < 0) return ret;
}
BitStream_writeBytes(bstream->data + bstream->length, size, data);
bstream->length += size * 8;
return 0;
}
unsigned char *BitStream_toByte(BitStream *bstream)
{
int i, j, size, bytes;
unsigned char *data, v;
unsigned char *p;
size = BitStream_size(bstream);
if(size == 0) {
return NULL;
}
data = (unsigned char *)malloc((size + 7) / 8);
if(data == NULL) {
return NULL;
}
bytes = size / 8;
p = bstream->data;
for(i=0; i<bytes; i++) {
v = 0;
for(j=0; j<8; j++) {
v = v << 1;
v |= *p;
p++;
}
data[i] = v;
}
if(size & 7) {
v = 0;
for(j=0; j<(size & 7); j++) {
v = v << 1;
v |= *p;
p++;
}
data[bytes] = v;
}
return data;
}
void BitStream_free(BitStream *bstream)
{
if(bstream != NULL) {
free(bstream->data);
free(bstream);
}
}
