chore(Deps/Zlib): Upgrade zlib to 1.3.1 (#21940)
This commit is contained in:
Vendored
+290
-355
@@ -1,5 +1,5 @@
|
||||
/* trees.c -- output deflated data using Huffman coding
|
||||
* Copyright (C) 1995-2021 Jean-loup Gailly
|
||||
* Copyright (C) 1995-2024 Jean-loup Gailly
|
||||
* detect_data_type() function provided freely by Cosmin Truta, 2006
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
@@ -122,39 +122,116 @@ struct static_tree_desc_s {
|
||||
int max_length; /* max bit length for the codes */
|
||||
};
|
||||
|
||||
local const static_tree_desc static_l_desc =
|
||||
#ifdef NO_INIT_GLOBAL_POINTERS
|
||||
# define TCONST
|
||||
#else
|
||||
# define TCONST const
|
||||
#endif
|
||||
|
||||
local TCONST static_tree_desc static_l_desc =
|
||||
{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
|
||||
|
||||
local const static_tree_desc static_d_desc =
|
||||
local TCONST static_tree_desc static_d_desc =
|
||||
{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
|
||||
|
||||
local const static_tree_desc static_bl_desc =
|
||||
local TCONST static_tree_desc static_bl_desc =
|
||||
{(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
|
||||
|
||||
/* ===========================================================================
|
||||
* Local (static) routines in this file.
|
||||
* Output a short LSB first on the stream.
|
||||
* IN assertion: there is enough room in pendingBuf.
|
||||
*/
|
||||
#define put_short(s, w) { \
|
||||
put_byte(s, (uch)((w) & 0xff)); \
|
||||
put_byte(s, (uch)((ush)(w) >> 8)); \
|
||||
}
|
||||
|
||||
local void tr_static_init OF((void));
|
||||
local void init_block OF((deflate_state *s));
|
||||
local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
|
||||
local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
|
||||
local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
|
||||
local void build_tree OF((deflate_state *s, tree_desc *desc));
|
||||
local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
|
||||
local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
|
||||
local int build_bl_tree OF((deflate_state *s));
|
||||
local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
|
||||
int blcodes));
|
||||
local void compress_block OF((deflate_state *s, const ct_data *ltree,
|
||||
const ct_data *dtree));
|
||||
local int detect_data_type OF((deflate_state *s));
|
||||
local unsigned bi_reverse OF((unsigned code, int len));
|
||||
local void bi_windup OF((deflate_state *s));
|
||||
local void bi_flush OF((deflate_state *s));
|
||||
/* ===========================================================================
|
||||
* Reverse the first len bits of a code, using straightforward code (a faster
|
||||
* method would use a table)
|
||||
* IN assertion: 1 <= len <= 15
|
||||
*/
|
||||
local unsigned bi_reverse(unsigned code, int len) {
|
||||
register unsigned res = 0;
|
||||
do {
|
||||
res |= code & 1;
|
||||
code >>= 1, res <<= 1;
|
||||
} while (--len > 0);
|
||||
return res >> 1;
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Flush the bit buffer, keeping at most 7 bits in it.
|
||||
*/
|
||||
local void bi_flush(deflate_state *s) {
|
||||
if (s->bi_valid == 16) {
|
||||
put_short(s, s->bi_buf);
|
||||
s->bi_buf = 0;
|
||||
s->bi_valid = 0;
|
||||
} else if (s->bi_valid >= 8) {
|
||||
put_byte(s, (Byte)s->bi_buf);
|
||||
s->bi_buf >>= 8;
|
||||
s->bi_valid -= 8;
|
||||
}
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Flush the bit buffer and align the output on a byte boundary
|
||||
*/
|
||||
local void bi_windup(deflate_state *s) {
|
||||
if (s->bi_valid > 8) {
|
||||
put_short(s, s->bi_buf);
|
||||
} else if (s->bi_valid > 0) {
|
||||
put_byte(s, (Byte)s->bi_buf);
|
||||
}
|
||||
s->bi_buf = 0;
|
||||
s->bi_valid = 0;
|
||||
#ifdef ZLIB_DEBUG
|
||||
s->bits_sent = (s->bits_sent + 7) & ~7;
|
||||
#endif
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Generate the codes for a given tree and bit counts (which need not be
|
||||
* optimal).
|
||||
* IN assertion: the array bl_count contains the bit length statistics for
|
||||
* the given tree and the field len is set for all tree elements.
|
||||
* OUT assertion: the field code is set for all tree elements of non
|
||||
* zero code length.
|
||||
*/
|
||||
local void gen_codes(ct_data *tree, int max_code, ushf *bl_count) {
|
||||
ush next_code[MAX_BITS+1]; /* next code value for each bit length */
|
||||
unsigned code = 0; /* running code value */
|
||||
int bits; /* bit index */
|
||||
int n; /* code index */
|
||||
|
||||
/* The distribution counts are first used to generate the code values
|
||||
* without bit reversal.
|
||||
*/
|
||||
for (bits = 1; bits <= MAX_BITS; bits++) {
|
||||
code = (code + bl_count[bits - 1]) << 1;
|
||||
next_code[bits] = (ush)code;
|
||||
}
|
||||
/* Check that the bit counts in bl_count are consistent. The last code
|
||||
* must be all ones.
|
||||
*/
|
||||
Assert (code + bl_count[MAX_BITS] - 1 == (1 << MAX_BITS) - 1,
|
||||
"inconsistent bit counts");
|
||||
Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
|
||||
|
||||
for (n = 0; n <= max_code; n++) {
|
||||
int len = tree[n].Len;
|
||||
if (len == 0) continue;
|
||||
/* Now reverse the bits */
|
||||
tree[n].Code = (ush)bi_reverse(next_code[len]++, len);
|
||||
|
||||
Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
|
||||
n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len] - 1));
|
||||
}
|
||||
}
|
||||
|
||||
#ifdef GEN_TREES_H
|
||||
local void gen_trees_header OF((void));
|
||||
local void gen_trees_header(void);
|
||||
#endif
|
||||
|
||||
#ifndef ZLIB_DEBUG
|
||||
@@ -167,33 +244,18 @@ local void gen_trees_header OF((void));
|
||||
send_bits(s, tree[c].Code, tree[c].Len); }
|
||||
#endif
|
||||
|
||||
/* ===========================================================================
|
||||
* Output a short LSB first on the stream.
|
||||
* IN assertion: there is enough room in pendingBuf.
|
||||
*/
|
||||
#define put_short(s, w) { \
|
||||
put_byte(s, (uch)((w) & 0xff)); \
|
||||
put_byte(s, (uch)((ush)(w) >> 8)); \
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Send a value on a given number of bits.
|
||||
* IN assertion: length <= 16 and value fits in length bits.
|
||||
*/
|
||||
#ifdef ZLIB_DEBUG
|
||||
local void send_bits OF((deflate_state *s, int value, int length));
|
||||
|
||||
local void send_bits(s, value, length)
|
||||
deflate_state *s;
|
||||
int value; /* value to send */
|
||||
int length; /* number of bits */
|
||||
{
|
||||
local void send_bits(deflate_state *s, int value, int length) {
|
||||
Tracevv((stderr," l %2d v %4x ", length, value));
|
||||
Assert(length > 0 && length <= 15, "invalid length");
|
||||
s->bits_sent += (ulg)length;
|
||||
|
||||
/* If not enough room in bi_buf, use (valid) bits from bi_buf and
|
||||
* (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
|
||||
* (16 - bi_valid) bits from value, leaving (width - (16 - bi_valid))
|
||||
* unused bits in value.
|
||||
*/
|
||||
if (s->bi_valid > (int)Buf_size - length) {
|
||||
@@ -229,8 +291,7 @@ local void send_bits(s, value, length)
|
||||
/* ===========================================================================
|
||||
* Initialize the various 'constant' tables.
|
||||
*/
|
||||
local void tr_static_init()
|
||||
{
|
||||
local void tr_static_init(void) {
|
||||
#if defined(GEN_TREES_H) || !defined(STDC)
|
||||
static int static_init_done = 0;
|
||||
int n; /* iterates over tree elements */
|
||||
@@ -256,7 +317,7 @@ local void tr_static_init()
|
||||
length = 0;
|
||||
for (code = 0; code < LENGTH_CODES-1; code++) {
|
||||
base_length[code] = length;
|
||||
for (n = 0; n < (1<<extra_lbits[code]); n++) {
|
||||
for (n = 0; n < (1 << extra_lbits[code]); n++) {
|
||||
_length_code[length++] = (uch)code;
|
||||
}
|
||||
}
|
||||
@@ -265,13 +326,13 @@ local void tr_static_init()
|
||||
* in two different ways: code 284 + 5 bits or code 285, so we
|
||||
* overwrite length_code[255] to use the best encoding:
|
||||
*/
|
||||
_length_code[length-1] = (uch)code;
|
||||
_length_code[length - 1] = (uch)code;
|
||||
|
||||
/* Initialize the mapping dist (0..32K) -> dist code (0..29) */
|
||||
dist = 0;
|
||||
for (code = 0 ; code < 16; code++) {
|
||||
base_dist[code] = dist;
|
||||
for (n = 0; n < (1<<extra_dbits[code]); n++) {
|
||||
for (n = 0; n < (1 << extra_dbits[code]); n++) {
|
||||
_dist_code[dist++] = (uch)code;
|
||||
}
|
||||
}
|
||||
@@ -279,11 +340,11 @@ local void tr_static_init()
|
||||
dist >>= 7; /* from now on, all distances are divided by 128 */
|
||||
for ( ; code < D_CODES; code++) {
|
||||
base_dist[code] = dist << 7;
|
||||
for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
|
||||
for (n = 0; n < (1 << (extra_dbits[code] - 7)); n++) {
|
||||
_dist_code[256 + dist++] = (uch)code;
|
||||
}
|
||||
}
|
||||
Assert (dist == 256, "tr_static_init: 256+dist != 512");
|
||||
Assert (dist == 256, "tr_static_init: 256 + dist != 512");
|
||||
|
||||
/* Construct the codes of the static literal tree */
|
||||
for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
|
||||
@@ -312,7 +373,7 @@ local void tr_static_init()
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Genererate the file trees.h describing the static trees.
|
||||
* Generate the file trees.h describing the static trees.
|
||||
*/
|
||||
#ifdef GEN_TREES_H
|
||||
# ifndef ZLIB_DEBUG
|
||||
@@ -321,10 +382,9 @@ local void tr_static_init()
|
||||
|
||||
# define SEPARATOR(i, last, width) \
|
||||
((i) == (last)? "\n};\n\n" : \
|
||||
((i) % (width) == (width)-1 ? ",\n" : ", "))
|
||||
((i) % (width) == (width) - 1 ? ",\n" : ", "))
|
||||
|
||||
void gen_trees_header()
|
||||
{
|
||||
void gen_trees_header(void) {
|
||||
FILE *header = fopen("trees.h", "w");
|
||||
int i;
|
||||
|
||||
@@ -373,12 +433,26 @@ void gen_trees_header()
|
||||
}
|
||||
#endif /* GEN_TREES_H */
|
||||
|
||||
/* ===========================================================================
|
||||
* Initialize a new block.
|
||||
*/
|
||||
local void init_block(deflate_state *s) {
|
||||
int n; /* iterates over tree elements */
|
||||
|
||||
/* Initialize the trees. */
|
||||
for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
|
||||
for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
|
||||
for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
|
||||
|
||||
s->dyn_ltree[END_BLOCK].Freq = 1;
|
||||
s->opt_len = s->static_len = 0L;
|
||||
s->sym_next = s->matches = 0;
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Initialize the tree data structures for a new zlib stream.
|
||||
*/
|
||||
void ZLIB_INTERNAL _tr_init(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
void ZLIB_INTERNAL _tr_init(deflate_state *s) {
|
||||
tr_static_init();
|
||||
|
||||
s->l_desc.dyn_tree = s->dyn_ltree;
|
||||
@@ -401,24 +475,6 @@ void ZLIB_INTERNAL _tr_init(s)
|
||||
init_block(s);
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Initialize a new block.
|
||||
*/
|
||||
local void init_block(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
int n; /* iterates over tree elements */
|
||||
|
||||
/* Initialize the trees. */
|
||||
for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
|
||||
for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
|
||||
for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
|
||||
|
||||
s->dyn_ltree[END_BLOCK].Freq = 1;
|
||||
s->opt_len = s->static_len = 0L;
|
||||
s->sym_next = s->matches = 0;
|
||||
}
|
||||
|
||||
#define SMALLEST 1
|
||||
/* Index within the heap array of least frequent node in the Huffman tree */
|
||||
|
||||
@@ -448,17 +504,13 @@ local void init_block(s)
|
||||
* when the heap property is re-established (each father smaller than its
|
||||
* two sons).
|
||||
*/
|
||||
local void pqdownheap(s, tree, k)
|
||||
deflate_state *s;
|
||||
ct_data *tree; /* the tree to restore */
|
||||
int k; /* node to move down */
|
||||
{
|
||||
local void pqdownheap(deflate_state *s, ct_data *tree, int k) {
|
||||
int v = s->heap[k];
|
||||
int j = k << 1; /* left son of k */
|
||||
while (j <= s->heap_len) {
|
||||
/* Set j to the smallest of the two sons: */
|
||||
if (j < s->heap_len &&
|
||||
smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
|
||||
smaller(tree, s->heap[j + 1], s->heap[j], s->depth)) {
|
||||
j++;
|
||||
}
|
||||
/* Exit if v is smaller than both sons */
|
||||
@@ -483,10 +535,7 @@ local void pqdownheap(s, tree, k)
|
||||
* The length opt_len is updated; static_len is also updated if stree is
|
||||
* not null.
|
||||
*/
|
||||
local void gen_bitlen(s, desc)
|
||||
deflate_state *s;
|
||||
tree_desc *desc; /* the tree descriptor */
|
||||
{
|
||||
local void gen_bitlen(deflate_state *s, tree_desc *desc) {
|
||||
ct_data *tree = desc->dyn_tree;
|
||||
int max_code = desc->max_code;
|
||||
const ct_data *stree = desc->stat_desc->static_tree;
|
||||
@@ -507,7 +556,7 @@ local void gen_bitlen(s, desc)
|
||||
*/
|
||||
tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
|
||||
|
||||
for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
|
||||
for (h = s->heap_max + 1; h < HEAP_SIZE; h++) {
|
||||
n = s->heap[h];
|
||||
bits = tree[tree[n].Dad].Len + 1;
|
||||
if (bits > max_length) bits = max_length, overflow++;
|
||||
@@ -518,7 +567,7 @@ local void gen_bitlen(s, desc)
|
||||
|
||||
s->bl_count[bits]++;
|
||||
xbits = 0;
|
||||
if (n >= base) xbits = extra[n-base];
|
||||
if (n >= base) xbits = extra[n - base];
|
||||
f = tree[n].Freq;
|
||||
s->opt_len += (ulg)f * (unsigned)(bits + xbits);
|
||||
if (stree) s->static_len += (ulg)f * (unsigned)(stree[n].Len + xbits);
|
||||
@@ -530,10 +579,10 @@ local void gen_bitlen(s, desc)
|
||||
|
||||
/* Find the first bit length which could increase: */
|
||||
do {
|
||||
bits = max_length-1;
|
||||
bits = max_length - 1;
|
||||
while (s->bl_count[bits] == 0) bits--;
|
||||
s->bl_count[bits]--; /* move one leaf down the tree */
|
||||
s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
|
||||
s->bl_count[bits]--; /* move one leaf down the tree */
|
||||
s->bl_count[bits + 1] += 2; /* move one overflow item as its brother */
|
||||
s->bl_count[max_length]--;
|
||||
/* The brother of the overflow item also moves one step up,
|
||||
* but this does not affect bl_count[max_length]
|
||||
@@ -561,48 +610,9 @@ local void gen_bitlen(s, desc)
|
||||
}
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Generate the codes for a given tree and bit counts (which need not be
|
||||
* optimal).
|
||||
* IN assertion: the array bl_count contains the bit length statistics for
|
||||
* the given tree and the field len is set for all tree elements.
|
||||
* OUT assertion: the field code is set for all tree elements of non
|
||||
* zero code length.
|
||||
*/
|
||||
local void gen_codes (tree, max_code, bl_count)
|
||||
ct_data *tree; /* the tree to decorate */
|
||||
int max_code; /* largest code with non zero frequency */
|
||||
ushf *bl_count; /* number of codes at each bit length */
|
||||
{
|
||||
ush next_code[MAX_BITS+1]; /* next code value for each bit length */
|
||||
unsigned code = 0; /* running code value */
|
||||
int bits; /* bit index */
|
||||
int n; /* code index */
|
||||
|
||||
/* The distribution counts are first used to generate the code values
|
||||
* without bit reversal.
|
||||
*/
|
||||
for (bits = 1; bits <= MAX_BITS; bits++) {
|
||||
code = (code + bl_count[bits-1]) << 1;
|
||||
next_code[bits] = (ush)code;
|
||||
}
|
||||
/* Check that the bit counts in bl_count are consistent. The last code
|
||||
* must be all ones.
|
||||
*/
|
||||
Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
|
||||
"inconsistent bit counts");
|
||||
Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
|
||||
|
||||
for (n = 0; n <= max_code; n++) {
|
||||
int len = tree[n].Len;
|
||||
if (len == 0) continue;
|
||||
/* Now reverse the bits */
|
||||
tree[n].Code = (ush)bi_reverse(next_code[len]++, len);
|
||||
|
||||
Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
|
||||
n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
|
||||
}
|
||||
}
|
||||
#ifdef DUMP_BL_TREE
|
||||
# include <stdio.h>
|
||||
#endif
|
||||
|
||||
/* ===========================================================================
|
||||
* Construct one Huffman tree and assigns the code bit strings and lengths.
|
||||
@@ -612,10 +622,7 @@ local void gen_codes (tree, max_code, bl_count)
|
||||
* and corresponding code. The length opt_len is updated; static_len is
|
||||
* also updated if stree is not null. The field max_code is set.
|
||||
*/
|
||||
local void build_tree(s, desc)
|
||||
deflate_state *s;
|
||||
tree_desc *desc; /* the tree descriptor */
|
||||
{
|
||||
local void build_tree(deflate_state *s, tree_desc *desc) {
|
||||
ct_data *tree = desc->dyn_tree;
|
||||
const ct_data *stree = desc->stat_desc->static_tree;
|
||||
int elems = desc->stat_desc->elems;
|
||||
@@ -624,7 +631,7 @@ local void build_tree(s, desc)
|
||||
int node; /* new node being created */
|
||||
|
||||
/* Construct the initial heap, with least frequent element in
|
||||
* heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
|
||||
* heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n + 1].
|
||||
* heap[0] is not used.
|
||||
*/
|
||||
s->heap_len = 0, s->heap_max = HEAP_SIZE;
|
||||
@@ -652,7 +659,7 @@ local void build_tree(s, desc)
|
||||
}
|
||||
desc->max_code = max_code;
|
||||
|
||||
/* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
|
||||
/* The elements heap[heap_len/2 + 1 .. heap_len] are leaves of the tree,
|
||||
* establish sub-heaps of increasing lengths:
|
||||
*/
|
||||
for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
|
||||
@@ -700,11 +707,7 @@ local void build_tree(s, desc)
|
||||
* Scan a literal or distance tree to determine the frequencies of the codes
|
||||
* in the bit length tree.
|
||||
*/
|
||||
local void scan_tree (s, tree, max_code)
|
||||
deflate_state *s;
|
||||
ct_data *tree; /* the tree to be scanned */
|
||||
int max_code; /* and its largest code of non zero frequency */
|
||||
{
|
||||
local void scan_tree(deflate_state *s, ct_data *tree, int max_code) {
|
||||
int n; /* iterates over all tree elements */
|
||||
int prevlen = -1; /* last emitted length */
|
||||
int curlen; /* length of current code */
|
||||
@@ -714,10 +717,10 @@ local void scan_tree (s, tree, max_code)
|
||||
int min_count = 4; /* min repeat count */
|
||||
|
||||
if (nextlen == 0) max_count = 138, min_count = 3;
|
||||
tree[max_code+1].Len = (ush)0xffff; /* guard */
|
||||
tree[max_code + 1].Len = (ush)0xffff; /* guard */
|
||||
|
||||
for (n = 0; n <= max_code; n++) {
|
||||
curlen = nextlen; nextlen = tree[n+1].Len;
|
||||
curlen = nextlen; nextlen = tree[n + 1].Len;
|
||||
if (++count < max_count && curlen == nextlen) {
|
||||
continue;
|
||||
} else if (count < min_count) {
|
||||
@@ -745,11 +748,7 @@ local void scan_tree (s, tree, max_code)
|
||||
* Send a literal or distance tree in compressed form, using the codes in
|
||||
* bl_tree.
|
||||
*/
|
||||
local void send_tree (s, tree, max_code)
|
||||
deflate_state *s;
|
||||
ct_data *tree; /* the tree to be scanned */
|
||||
int max_code; /* and its largest code of non zero frequency */
|
||||
{
|
||||
local void send_tree(deflate_state *s, ct_data *tree, int max_code) {
|
||||
int n; /* iterates over all tree elements */
|
||||
int prevlen = -1; /* last emitted length */
|
||||
int curlen; /* length of current code */
|
||||
@@ -758,11 +757,11 @@ local void send_tree (s, tree, max_code)
|
||||
int max_count = 7; /* max repeat count */
|
||||
int min_count = 4; /* min repeat count */
|
||||
|
||||
/* tree[max_code+1].Len = -1; */ /* guard already set */
|
||||
/* tree[max_code + 1].Len = -1; */ /* guard already set */
|
||||
if (nextlen == 0) max_count = 138, min_count = 3;
|
||||
|
||||
for (n = 0; n <= max_code; n++) {
|
||||
curlen = nextlen; nextlen = tree[n+1].Len;
|
||||
curlen = nextlen; nextlen = tree[n + 1].Len;
|
||||
if (++count < max_count && curlen == nextlen) {
|
||||
continue;
|
||||
} else if (count < min_count) {
|
||||
@@ -773,13 +772,13 @@ local void send_tree (s, tree, max_code)
|
||||
send_code(s, curlen, s->bl_tree); count--;
|
||||
}
|
||||
Assert(count >= 3 && count <= 6, " 3_6?");
|
||||
send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
|
||||
send_code(s, REP_3_6, s->bl_tree); send_bits(s, count - 3, 2);
|
||||
|
||||
} else if (count <= 10) {
|
||||
send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
|
||||
send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count - 3, 3);
|
||||
|
||||
} else {
|
||||
send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
|
||||
send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count - 11, 7);
|
||||
}
|
||||
count = 0; prevlen = curlen;
|
||||
if (nextlen == 0) {
|
||||
@@ -796,9 +795,7 @@ local void send_tree (s, tree, max_code)
|
||||
* Construct the Huffman tree for the bit lengths and return the index in
|
||||
* bl_order of the last bit length code to send.
|
||||
*/
|
||||
local int build_bl_tree(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
local int build_bl_tree(deflate_state *s) {
|
||||
int max_blindex; /* index of last bit length code of non zero freq */
|
||||
|
||||
/* Determine the bit length frequencies for literal and distance trees */
|
||||
@@ -807,8 +804,8 @@ local int build_bl_tree(s)
|
||||
|
||||
/* Build the bit length tree: */
|
||||
build_tree(s, (tree_desc *)(&(s->bl_desc)));
|
||||
/* opt_len now includes the length of the tree representations, except
|
||||
* the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
|
||||
/* opt_len now includes the length of the tree representations, except the
|
||||
* lengths of the bit lengths codes and the 5 + 5 + 4 bits for the counts.
|
||||
*/
|
||||
|
||||
/* Determine the number of bit length codes to send. The pkzip format
|
||||
@@ -819,7 +816,7 @@ local int build_bl_tree(s)
|
||||
if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
|
||||
}
|
||||
/* Update opt_len to include the bit length tree and counts */
|
||||
s->opt_len += 3*((ulg)max_blindex+1) + 5+5+4;
|
||||
s->opt_len += 3*((ulg)max_blindex + 1) + 5 + 5 + 4;
|
||||
Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
|
||||
s->opt_len, s->static_len));
|
||||
|
||||
@@ -831,42 +828,36 @@ local int build_bl_tree(s)
|
||||
* lengths of the bit length codes, the literal tree and the distance tree.
|
||||
* IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
|
||||
*/
|
||||
local void send_all_trees(s, lcodes, dcodes, blcodes)
|
||||
deflate_state *s;
|
||||
int lcodes, dcodes, blcodes; /* number of codes for each tree */
|
||||
{
|
||||
local void send_all_trees(deflate_state *s, int lcodes, int dcodes,
|
||||
int blcodes) {
|
||||
int rank; /* index in bl_order */
|
||||
|
||||
Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
|
||||
Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
|
||||
"too many codes");
|
||||
Tracev((stderr, "\nbl counts: "));
|
||||
send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
|
||||
send_bits(s, dcodes-1, 5);
|
||||
send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
|
||||
send_bits(s, lcodes - 257, 5); /* not +255 as stated in appnote.txt */
|
||||
send_bits(s, dcodes - 1, 5);
|
||||
send_bits(s, blcodes - 4, 4); /* not -3 as stated in appnote.txt */
|
||||
for (rank = 0; rank < blcodes; rank++) {
|
||||
Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
|
||||
send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
|
||||
}
|
||||
Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
|
||||
|
||||
send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
|
||||
send_tree(s, (ct_data *)s->dyn_ltree, lcodes - 1); /* literal tree */
|
||||
Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
|
||||
|
||||
send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
|
||||
send_tree(s, (ct_data *)s->dyn_dtree, dcodes - 1); /* distance tree */
|
||||
Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Send a stored block
|
||||
*/
|
||||
void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last)
|
||||
deflate_state *s;
|
||||
charf *buf; /* input block */
|
||||
ulg stored_len; /* length of input block */
|
||||
int last; /* one if this is the last block for a file */
|
||||
{
|
||||
send_bits(s, (STORED_BLOCK<<1)+last, 3); /* send block type */
|
||||
void ZLIB_INTERNAL _tr_stored_block(deflate_state *s, charf *buf,
|
||||
ulg stored_len, int last) {
|
||||
send_bits(s, (STORED_BLOCK<<1) + last, 3); /* send block type */
|
||||
bi_windup(s); /* align on byte boundary */
|
||||
put_short(s, (ush)stored_len);
|
||||
put_short(s, (ush)~stored_len);
|
||||
@@ -877,16 +868,14 @@ void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last)
|
||||
s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
|
||||
s->compressed_len += (stored_len + 4) << 3;
|
||||
s->bits_sent += 2*16;
|
||||
s->bits_sent += stored_len<<3;
|
||||
s->bits_sent += stored_len << 3;
|
||||
#endif
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Flush the bits in the bit buffer to pending output (leaves at most 7 bits)
|
||||
*/
|
||||
void ZLIB_INTERNAL _tr_flush_bits(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
void ZLIB_INTERNAL _tr_flush_bits(deflate_state *s) {
|
||||
bi_flush(s);
|
||||
}
|
||||
|
||||
@@ -894,9 +883,7 @@ void ZLIB_INTERNAL _tr_flush_bits(s)
|
||||
* Send one empty static block to give enough lookahead for inflate.
|
||||
* This takes 10 bits, of which 7 may remain in the bit buffer.
|
||||
*/
|
||||
void ZLIB_INTERNAL _tr_align(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
void ZLIB_INTERNAL _tr_align(deflate_state *s) {
|
||||
send_bits(s, STATIC_TREES<<1, 3);
|
||||
send_code(s, END_BLOCK, static_ltree);
|
||||
#ifdef ZLIB_DEBUG
|
||||
@@ -905,16 +892,108 @@ void ZLIB_INTERNAL _tr_align(s)
|
||||
bi_flush(s);
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Send the block data compressed using the given Huffman trees
|
||||
*/
|
||||
local void compress_block(deflate_state *s, const ct_data *ltree,
|
||||
const ct_data *dtree) {
|
||||
unsigned dist; /* distance of matched string */
|
||||
int lc; /* match length or unmatched char (if dist == 0) */
|
||||
unsigned sx = 0; /* running index in symbol buffers */
|
||||
unsigned code; /* the code to send */
|
||||
int extra; /* number of extra bits to send */
|
||||
|
||||
if (s->sym_next != 0) do {
|
||||
#ifdef LIT_MEM
|
||||
dist = s->d_buf[sx];
|
||||
lc = s->l_buf[sx++];
|
||||
#else
|
||||
dist = s->sym_buf[sx++] & 0xff;
|
||||
dist += (unsigned)(s->sym_buf[sx++] & 0xff) << 8;
|
||||
lc = s->sym_buf[sx++];
|
||||
#endif
|
||||
if (dist == 0) {
|
||||
send_code(s, lc, ltree); /* send a literal byte */
|
||||
Tracecv(isgraph(lc), (stderr," '%c' ", lc));
|
||||
} else {
|
||||
/* Here, lc is the match length - MIN_MATCH */
|
||||
code = _length_code[lc];
|
||||
send_code(s, code + LITERALS + 1, ltree); /* send length code */
|
||||
extra = extra_lbits[code];
|
||||
if (extra != 0) {
|
||||
lc -= base_length[code];
|
||||
send_bits(s, lc, extra); /* send the extra length bits */
|
||||
}
|
||||
dist--; /* dist is now the match distance - 1 */
|
||||
code = d_code(dist);
|
||||
Assert (code < D_CODES, "bad d_code");
|
||||
|
||||
send_code(s, code, dtree); /* send the distance code */
|
||||
extra = extra_dbits[code];
|
||||
if (extra != 0) {
|
||||
dist -= (unsigned)base_dist[code];
|
||||
send_bits(s, dist, extra); /* send the extra distance bits */
|
||||
}
|
||||
} /* literal or match pair ? */
|
||||
|
||||
/* Check for no overlay of pending_buf on needed symbols */
|
||||
#ifdef LIT_MEM
|
||||
Assert(s->pending < 2 * (s->lit_bufsize + sx), "pendingBuf overflow");
|
||||
#else
|
||||
Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");
|
||||
#endif
|
||||
|
||||
} while (sx < s->sym_next);
|
||||
|
||||
send_code(s, END_BLOCK, ltree);
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Check if the data type is TEXT or BINARY, using the following algorithm:
|
||||
* - TEXT if the two conditions below are satisfied:
|
||||
* a) There are no non-portable control characters belonging to the
|
||||
* "block list" (0..6, 14..25, 28..31).
|
||||
* b) There is at least one printable character belonging to the
|
||||
* "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
|
||||
* - BINARY otherwise.
|
||||
* - The following partially-portable control characters form a
|
||||
* "gray list" that is ignored in this detection algorithm:
|
||||
* (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
|
||||
* IN assertion: the fields Freq of dyn_ltree are set.
|
||||
*/
|
||||
local int detect_data_type(deflate_state *s) {
|
||||
/* block_mask is the bit mask of block-listed bytes
|
||||
* set bits 0..6, 14..25, and 28..31
|
||||
* 0xf3ffc07f = binary 11110011111111111100000001111111
|
||||
*/
|
||||
unsigned long block_mask = 0xf3ffc07fUL;
|
||||
int n;
|
||||
|
||||
/* Check for non-textual ("block-listed") bytes. */
|
||||
for (n = 0; n <= 31; n++, block_mask >>= 1)
|
||||
if ((block_mask & 1) && (s->dyn_ltree[n].Freq != 0))
|
||||
return Z_BINARY;
|
||||
|
||||
/* Check for textual ("allow-listed") bytes. */
|
||||
if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0
|
||||
|| s->dyn_ltree[13].Freq != 0)
|
||||
return Z_TEXT;
|
||||
for (n = 32; n < LITERALS; n++)
|
||||
if (s->dyn_ltree[n].Freq != 0)
|
||||
return Z_TEXT;
|
||||
|
||||
/* There are no "block-listed" or "allow-listed" bytes:
|
||||
* this stream either is empty or has tolerated ("gray-listed") bytes only.
|
||||
*/
|
||||
return Z_BINARY;
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Determine the best encoding for the current block: dynamic trees, static
|
||||
* trees or store, and write out the encoded block.
|
||||
*/
|
||||
void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
|
||||
deflate_state *s;
|
||||
charf *buf; /* input block, or NULL if too old */
|
||||
ulg stored_len; /* length of input block */
|
||||
int last; /* one if this is the last block for a file */
|
||||
{
|
||||
void ZLIB_INTERNAL _tr_flush_block(deflate_state *s, charf *buf,
|
||||
ulg stored_len, int last) {
|
||||
ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
|
||||
int max_blindex = 0; /* index of last bit length code of non zero freq */
|
||||
|
||||
@@ -943,14 +1022,17 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
|
||||
max_blindex = build_bl_tree(s);
|
||||
|
||||
/* Determine the best encoding. Compute the block lengths in bytes. */
|
||||
opt_lenb = (s->opt_len+3+7)>>3;
|
||||
static_lenb = (s->static_len+3+7)>>3;
|
||||
opt_lenb = (s->opt_len + 3 + 7) >> 3;
|
||||
static_lenb = (s->static_len + 3 + 7) >> 3;
|
||||
|
||||
Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
|
||||
opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
|
||||
s->sym_next / 3));
|
||||
|
||||
if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
|
||||
#ifndef FORCE_STATIC
|
||||
if (static_lenb <= opt_lenb || s->strategy == Z_FIXED)
|
||||
#endif
|
||||
opt_lenb = static_lenb;
|
||||
|
||||
} else {
|
||||
Assert(buf != (char*)0, "lost buf");
|
||||
@@ -960,7 +1042,7 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
|
||||
#ifdef FORCE_STORED
|
||||
if (buf != (char*)0) { /* force stored block */
|
||||
#else
|
||||
if (stored_len+4 <= opt_lenb && buf != (char*)0) {
|
||||
if (stored_len + 4 <= opt_lenb && buf != (char*)0) {
|
||||
/* 4: two words for the lengths */
|
||||
#endif
|
||||
/* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
|
||||
@@ -971,21 +1053,17 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
|
||||
*/
|
||||
_tr_stored_block(s, buf, stored_len, last);
|
||||
|
||||
#ifdef FORCE_STATIC
|
||||
} else if (static_lenb >= 0) { /* force static trees */
|
||||
#else
|
||||
} else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) {
|
||||
#endif
|
||||
send_bits(s, (STATIC_TREES<<1)+last, 3);
|
||||
} else if (static_lenb == opt_lenb) {
|
||||
send_bits(s, (STATIC_TREES<<1) + last, 3);
|
||||
compress_block(s, (const ct_data *)static_ltree,
|
||||
(const ct_data *)static_dtree);
|
||||
#ifdef ZLIB_DEBUG
|
||||
s->compressed_len += 3 + s->static_len;
|
||||
#endif
|
||||
} else {
|
||||
send_bits(s, (DYN_TREES<<1)+last, 3);
|
||||
send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
|
||||
max_blindex+1);
|
||||
send_bits(s, (DYN_TREES<<1) + last, 3);
|
||||
send_all_trees(s, s->l_desc.max_code + 1, s->d_desc.max_code + 1,
|
||||
max_blindex + 1);
|
||||
compress_block(s, (const ct_data *)s->dyn_ltree,
|
||||
(const ct_data *)s->dyn_dtree);
|
||||
#ifdef ZLIB_DEBUG
|
||||
@@ -1004,22 +1082,23 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
|
||||
s->compressed_len += 7; /* align on byte boundary */
|
||||
#endif
|
||||
}
|
||||
Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
|
||||
s->compressed_len-7*last));
|
||||
Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len >> 3,
|
||||
s->compressed_len - 7*last));
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Save the match info and tally the frequency counts. Return true if
|
||||
* the current block must be flushed.
|
||||
*/
|
||||
int ZLIB_INTERNAL _tr_tally (s, dist, lc)
|
||||
deflate_state *s;
|
||||
unsigned dist; /* distance of matched string */
|
||||
unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
|
||||
{
|
||||
s->sym_buf[s->sym_next++] = dist;
|
||||
s->sym_buf[s->sym_next++] = dist >> 8;
|
||||
s->sym_buf[s->sym_next++] = lc;
|
||||
int ZLIB_INTERNAL _tr_tally(deflate_state *s, unsigned dist, unsigned lc) {
|
||||
#ifdef LIT_MEM
|
||||
s->d_buf[s->sym_next] = (ush)dist;
|
||||
s->l_buf[s->sym_next++] = (uch)lc;
|
||||
#else
|
||||
s->sym_buf[s->sym_next++] = (uch)dist;
|
||||
s->sym_buf[s->sym_next++] = (uch)(dist >> 8);
|
||||
s->sym_buf[s->sym_next++] = (uch)lc;
|
||||
#endif
|
||||
if (dist == 0) {
|
||||
/* lc is the unmatched char */
|
||||
s->dyn_ltree[lc].Freq++;
|
||||
@@ -1031,152 +1110,8 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc)
|
||||
(ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
|
||||
(ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
|
||||
|
||||
s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
|
||||
s->dyn_ltree[_length_code[lc] + LITERALS + 1].Freq++;
|
||||
s->dyn_dtree[d_code(dist)].Freq++;
|
||||
}
|
||||
return (s->sym_next == s->sym_end);
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Send the block data compressed using the given Huffman trees
|
||||
*/
|
||||
local void compress_block(s, ltree, dtree)
|
||||
deflate_state *s;
|
||||
const ct_data *ltree; /* literal tree */
|
||||
const ct_data *dtree; /* distance tree */
|
||||
{
|
||||
unsigned dist; /* distance of matched string */
|
||||
int lc; /* match length or unmatched char (if dist == 0) */
|
||||
unsigned sx = 0; /* running index in sym_buf */
|
||||
unsigned code; /* the code to send */
|
||||
int extra; /* number of extra bits to send */
|
||||
|
||||
if (s->sym_next != 0) do {
|
||||
dist = s->sym_buf[sx++] & 0xff;
|
||||
dist += (unsigned)(s->sym_buf[sx++] & 0xff) << 8;
|
||||
lc = s->sym_buf[sx++];
|
||||
if (dist == 0) {
|
||||
send_code(s, lc, ltree); /* send a literal byte */
|
||||
Tracecv(isgraph(lc), (stderr," '%c' ", lc));
|
||||
} else {
|
||||
/* Here, lc is the match length - MIN_MATCH */
|
||||
code = _length_code[lc];
|
||||
send_code(s, code+LITERALS+1, ltree); /* send the length code */
|
||||
extra = extra_lbits[code];
|
||||
if (extra != 0) {
|
||||
lc -= base_length[code];
|
||||
send_bits(s, lc, extra); /* send the extra length bits */
|
||||
}
|
||||
dist--; /* dist is now the match distance - 1 */
|
||||
code = d_code(dist);
|
||||
Assert (code < D_CODES, "bad d_code");
|
||||
|
||||
send_code(s, code, dtree); /* send the distance code */
|
||||
extra = extra_dbits[code];
|
||||
if (extra != 0) {
|
||||
dist -= (unsigned)base_dist[code];
|
||||
send_bits(s, dist, extra); /* send the extra distance bits */
|
||||
}
|
||||
} /* literal or match pair ? */
|
||||
|
||||
/* Check that the overlay between pending_buf and sym_buf is ok: */
|
||||
Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");
|
||||
|
||||
} while (sx < s->sym_next);
|
||||
|
||||
send_code(s, END_BLOCK, ltree);
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Check if the data type is TEXT or BINARY, using the following algorithm:
|
||||
* - TEXT if the two conditions below are satisfied:
|
||||
* a) There are no non-portable control characters belonging to the
|
||||
* "block list" (0..6, 14..25, 28..31).
|
||||
* b) There is at least one printable character belonging to the
|
||||
* "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
|
||||
* - BINARY otherwise.
|
||||
* - The following partially-portable control characters form a
|
||||
* "gray list" that is ignored in this detection algorithm:
|
||||
* (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
|
||||
* IN assertion: the fields Freq of dyn_ltree are set.
|
||||
*/
|
||||
local int detect_data_type(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
/* block_mask is the bit mask of block-listed bytes
|
||||
* set bits 0..6, 14..25, and 28..31
|
||||
* 0xf3ffc07f = binary 11110011111111111100000001111111
|
||||
*/
|
||||
unsigned long block_mask = 0xf3ffc07fUL;
|
||||
int n;
|
||||
|
||||
/* Check for non-textual ("block-listed") bytes. */
|
||||
for (n = 0; n <= 31; n++, block_mask >>= 1)
|
||||
if ((block_mask & 1) && (s->dyn_ltree[n].Freq != 0))
|
||||
return Z_BINARY;
|
||||
|
||||
/* Check for textual ("allow-listed") bytes. */
|
||||
if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0
|
||||
|| s->dyn_ltree[13].Freq != 0)
|
||||
return Z_TEXT;
|
||||
for (n = 32; n < LITERALS; n++)
|
||||
if (s->dyn_ltree[n].Freq != 0)
|
||||
return Z_TEXT;
|
||||
|
||||
/* There are no "block-listed" or "allow-listed" bytes:
|
||||
* this stream either is empty or has tolerated ("gray-listed") bytes only.
|
||||
*/
|
||||
return Z_BINARY;
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Reverse the first len bits of a code, using straightforward code (a faster
|
||||
* method would use a table)
|
||||
* IN assertion: 1 <= len <= 15
|
||||
*/
|
||||
local unsigned bi_reverse(code, len)
|
||||
unsigned code; /* the value to invert */
|
||||
int len; /* its bit length */
|
||||
{
|
||||
register unsigned res = 0;
|
||||
do {
|
||||
res |= code & 1;
|
||||
code >>= 1, res <<= 1;
|
||||
} while (--len > 0);
|
||||
return res >> 1;
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Flush the bit buffer, keeping at most 7 bits in it.
|
||||
*/
|
||||
local void bi_flush(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
if (s->bi_valid == 16) {
|
||||
put_short(s, s->bi_buf);
|
||||
s->bi_buf = 0;
|
||||
s->bi_valid = 0;
|
||||
} else if (s->bi_valid >= 8) {
|
||||
put_byte(s, (Byte)s->bi_buf);
|
||||
s->bi_buf >>= 8;
|
||||
s->bi_valid -= 8;
|
||||
}
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Flush the bit buffer and align the output on a byte boundary
|
||||
*/
|
||||
local void bi_windup(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
if (s->bi_valid > 8) {
|
||||
put_short(s, s->bi_buf);
|
||||
} else if (s->bi_valid > 0) {
|
||||
put_byte(s, (Byte)s->bi_buf);
|
||||
}
|
||||
s->bi_buf = 0;
|
||||
s->bi_valid = 0;
|
||||
#ifdef ZLIB_DEBUG
|
||||
s->bits_sent = (s->bits_sent+7) & ~7;
|
||||
#endif
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user