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zlib 1.2.3.1

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This commit is contained in:
Mark Adler
2011-09-09 23:25:27 -07:00
parent abf180a067
commit b1c19ca6d8
50 changed files with 3729 additions and 583 deletions
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54
trees.c
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@@ -1,5 +1,6 @@
/* trees.c -- output deflated data using Huffman coding
* Copyright (C) 1995-2005 Jean-loup Gailly
* Copyright (C) 1995-2006 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
*/
@@ -152,7 +153,7 @@ local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
int blcodes));
local void compress_block OF((deflate_state *s, ct_data *ltree,
ct_data *dtree));
local void set_data_type OF((deflate_state *s));
local int detect_data_type OF((deflate_state *s));
local unsigned bi_reverse OF((unsigned value, int length));
local void bi_windup OF((deflate_state *s));
local void bi_flush OF((deflate_state *s));
@@ -250,11 +251,13 @@ local void tr_static_init()
if (static_init_done) return;
/* For some embedded targets, global variables are not initialized: */
#ifdef NO_INIT_GLOBAL_POINTERS
static_l_desc.static_tree = static_ltree;
static_l_desc.extra_bits = extra_lbits;
static_d_desc.static_tree = static_dtree;
static_d_desc.extra_bits = extra_dbits;
static_bl_desc.extra_bits = extra_blbits;
#endif
/* Initialize the mapping length (0..255) -> length code (0..28) */
length = 0;
@@ -931,8 +934,8 @@ void _tr_flush_block(s, buf, stored_len, eof)
if (s->level > 0) {
/* Check if the file is binary or text */
if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN)
set_data_type(s);
if (s->strm->data_type == Z_UNKNOWN)
s->strm->data_type = detect_data_type(s);
/* Construct the literal and distance trees */
build_tree(s, (tree_desc *)(&(s->l_desc)));
@@ -1118,24 +1121,45 @@ local void compress_block(s, ltree, dtree)
}
/* ===========================================================================
* Set the data type to BINARY or TEXT, using a crude approximation:
* set it to Z_TEXT if all symbols are either printable characters (33 to 255)
* or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise.
* 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
* "black list" (0..6, 14..25, 28..31).
* b) There is at least one printable character belonging to the
* "white 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 void set_data_type(s)
local int detect_data_type(s)
deflate_state *s;
{
/* black_mask is the bit mask of black-listed bytes
* set bits 0..6, 14..25, and 28..31
* 0xf3ffc07f = binary 11110011111111111100000001111111
*/
unsigned long black_mask = 0xf3ffc07fUL;
int n;
for (n = 0; n < 9; n++)
/* Check for non-textual ("black-listed") bytes. */
for (n = 0; n <= 31; n++, black_mask >>= 1)
if ((black_mask & 1) && (s->dyn_ltree[n].Freq != 0))
return Z_BINARY;
/* Check for textual ("white-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)
break;
if (n == 9)
for (n = 14; n < 32; n++)
if (s->dyn_ltree[n].Freq != 0)
break;
s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY;
return Z_TEXT;
/* There are no "black-listed" or "white-listed" bytes:
* this stream either is empty or has tolerated ("gray-listed") bytes only.
*/
return Z_BINARY;
}
/* ===========================================================================