*/
/*
- * Copyright (C) 2012 Eric Biggers
+ * Copyright (C) 2012, 2013 Eric Biggers
*
* This file is part of wimlib, a library for working with WIM files.
*
* along with wimlib; if not, see http://www.gnu.org/licenses/.
*/
-#include "compress.h"
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+
+#include "wimlib/assert.h"
+#include "wimlib/compress.h"
+#include "wimlib/util.h"
+
#include <stdlib.h>
#include <string.h>
-static inline void flush_bits(struct output_bitstream *ostream)
+static inline void
+flush_bits(struct output_bitstream *ostream)
{
*(u16*)ostream->bit_output = cpu_to_le16(ostream->bitbuf);
ostream->bit_output = ostream->next_bit_output;
/* Writes @num_bits bits, given by the @num_bits least significant bits of
* @bits, to the output @ostream. */
-int bitstream_put_bits(struct output_bitstream *ostream, output_bitbuf_t bits,
- uint num_bits)
+int
+bitstream_put_bits(struct output_bitstream *ostream, output_bitbuf_t bits,
+ unsigned num_bits)
{
- uint rem_bits;
+ unsigned rem_bits;
wimlib_assert(num_bits <= 16);
if (num_bits <= ostream->free_bits) {
}
/* Flushes any remaining bits in the output buffer to the output byte stream. */
-int flush_output_bitstream(struct output_bitstream *ostream)
+int
+flush_output_bitstream(struct output_bitstream *ostream)
{
if (ostream->num_bytes_remaining + (ostream->output -
ostream->bit_output) < 2)
/* Initializes an output bit buffer to write its output to the memory location
* pointer to by @data. */
-void init_output_bitstream(struct output_bitstream *ostream, void *data,
- uint num_bytes)
+void
+init_output_bitstream(struct output_bitstream *ostream, void *data,
+ unsigned num_bytes)
{
wimlib_assert(num_bytes >= 4);
/* Comparator function for HuffmanLeafNodes. Sorts primarily by symbol
* frequency and secondarily by symbol value. */
-static int cmp_leaves_by_freq(const void *__leaf1, const void *__leaf2)
+static int
+cmp_leaves_by_freq(const void *__leaf1, const void *__leaf2)
{
const HuffmanLeafNode *leaf1 = __leaf1;
const HuffmanLeafNode *leaf2 = __leaf2;
/* Comparator function for HuffmanLeafNodes. Sorts primarily by code length and
* secondarily by symbol value. */
-static int cmp_leaves_by_code_len(const void *__leaf1, const void *__leaf2)
+static int
+cmp_leaves_by_code_len(const void *__leaf1, const void *__leaf2)
{
const HuffmanLeafNode *leaf1 = __leaf1;
const HuffmanLeafNode *leaf2 = __leaf2;
/* Recursive function to calculate the depth of the leaves in a Huffman tree.
* */
-static void huffman_tree_compute_path_lengths(HuffmanNode *node, u16 cur_len)
+static void
+huffman_tree_compute_path_lengths(HuffmanNode *node, u16 cur_len)
{
if (node->sym == (u16)(-1)) {
/* Intermediate node. */
}
}
-/* Creates a canonical Huffman code from an array of symbol frequencies.
+/* make_canonical_huffman_code: - Creates a canonical Huffman code from an array
+ * of symbol frequencies.
*
* The algorithm used is similar to the well-known algorithm that builds a
* Huffman tree using a minheap. In that algorithm, the leaf nodes are
* lens[i] bits of codewords[i] will contain the codeword
* for symbol i.
*/
-void make_canonical_huffman_code(uint num_syms, uint max_codeword_len,
- const u32 freq_tab[], u8 lens[],
- u16 codewords[])
+void
+make_canonical_huffman_code(unsigned num_syms, unsigned max_codeword_len,
+ const freq_t freq_tab[], u8 lens[],
+ u16 codewords[])
{
/* We require at least 2 possible symbols in the alphabet to produce a
* valid Huffman decoding table. It is allowed that fewer than 2 symbols
/* Calculate how many symbols have non-zero frequency. These are the
* symbols that actually appeared in the input. */
- uint num_used_symbols = 0;
- for (uint i = 0; i < num_syms; i++)
+ unsigned num_used_symbols = 0;
+ for (unsigned i = 0; i < num_syms; i++)
if (freq_tab[i] != 0)
num_used_symbols++;
/* Initialize the array of leaf nodes with the symbols and their
* frequencies. */
HuffmanLeafNode leaves[num_used_symbols];
- uint leaf_idx = 0;
- for (uint i = 0; i < num_syms; i++) {
+ unsigned leaf_idx = 0;
+ for (unsigned i = 0; i < num_syms; i++) {
if (freq_tab[i] != 0) {
leaves[leaf_idx].freq = freq_tab[i];
leaves[leaf_idx].sym = i;
* encoded data take up more room anyway, since binary
* data itself has 2 symbols. */
- uint sym = leaves[0].sym;
+ unsigned sym = leaves[0].sym;
codewords[0] = 0;
lens[0] = 1;
while (1) {
/* Lowest frequency node. */
- HuffmanNode *f1 = NULL;
+ HuffmanNode *f1;
/* Second lowest frequency node. */
- HuffmanNode *f2 = NULL;
+ HuffmanNode *f2;
- /* Get the lowest and second lowest frequency nodes from
- * the remaining leaves or from the intermediate nodes.
- * */
+ /* Get the lowest and second lowest frequency nodes from the
+ * remaining leaves or from the intermediate nodes. */
if (cur_leaf != end_leaf && (cur_inode == next_inode ||
cur_leaf->freq <= cur_inode->freq)) {
f2 = (HuffmanNode*)cur_leaf++;
} else if (cur_inode != next_inode) {
f2 = cur_inode++;
- }
-
- /* All nodes used up! */
- if (f1 == NULL || f2 == NULL)
+ } else {
+ /* All nodes used up! */
break;
+ }
/* next_inode becomes the parent of f1 and f2. */
* codewords approach the length
* log_2(num_used_symbols).
* */
- for (uint i = 0; i < num_used_symbols; i++)
+ for (unsigned i = 0; i < num_used_symbols; i++)
if (leaves[i].freq > 1)
leaves[i].freq >>= 1;
goto try_building_tree_again;
qsort(leaves, num_used_symbols, sizeof(leaves[0]), cmp_leaves_by_code_len);
u16 cur_codeword = 0;
- uint cur_codeword_len = 0;
- for (uint i = 0; i < num_used_symbols; i++) {
+ unsigned cur_codeword_len = 0;
+ for (unsigned i = 0; i < num_used_symbols; i++) {
/* Each time a codeword becomes one longer, the current codeword
* is left shifted by one place. This is part of the procedure
* whenever a codeword is used, 1 is added to the current
* codeword. */
- uint len_diff = leaves[i].path_len - cur_codeword_len;
+ unsigned len_diff = leaves[i].path_len - cur_codeword_len;
cur_codeword <<= len_diff;
cur_codeword_len += len_diff;
git://wimlib.net / wimlib / blobdiff