int
huffman_decode_file(FILE *in, FILE *out)
{
huffman_node *root, *p;
int c;
unsigned int data_count;
/* Read the Huffman code table. */
root = read_code_table(in, &data_count);
if(!root)
return 1;
/* Decode the file. */
p = root;
while(data_count > 0 && (c = fgetc(in)) != EOF)
{
unsigned char byte = (unsigned char)c;
unsigned char mask = 1;
while(data_count > 0 && mask)
{
p = byte & mask ? p->one : p->zero;
mask <<= 1;
if(p->isLeaf)
{
fputc(p->symbol, out);
p = root;
--data_count;
}
}
}
free_huffman_tree(root);
return 0;
}
static int start_new_block(LHANewDecoder *decoder)
{
int len;
// Read length of new block (in commands).
len = read_bits(&decoder->bit_stream_reader, 16);
if (len < 0) {
return 0;
}
decoder->block_remaining = (size_t) len;
// Read the temporary decode table, used to encode the codes table.
// The position table data structure is reused for this.
if (!read_temp_table(decoder)) {
return 0;
}
// Read the code table; this is encoded *using* the temp table.
if (!read_code_table(decoder)) {
return 0;
}
// Read the offset table.
if (!read_offset_table(decoder)) {
return 0;
}
return 1;
}
