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zlib 1.2.2.1

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This commit is contained in:
Mark Adler
2011-09-09 23:24:24 -07:00
parent 79fbcdc939
commit 9811b53dd9
36 changed files with 1334 additions and 429 deletions
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48
trees.c
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@@ -1,5 +1,5 @@
/* trees.c -- output deflated data using Huffman coding
* Copyright (C) 1995-2003 Jean-loup Gailly
* Copyright (C) 1995-2004 Jean-loup Gailly
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -930,8 +930,25 @@ void _tr_flush_block(s, buf, stored_len, eof)
/* Build the Huffman trees unless a stored block is forced */
if (s->level > 0) {
/* Check if the file is ascii or binary */
if (s->strm->data_type == Z_UNKNOWN) set_data_type(s);
/* Check if the file is binary or text */
if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN)
set_data_type(s);
#ifdef DEBUG
/* Write out literal/length frequencies for benchmarking */
if (z_verbose) {
FILE *freq;
freq = fopen("defreq.txt", "a");
if (freq != NULL) {
int n;
fputs("ltree:", freq);
for (n = 0; n < L_CODES; n++)
fprintf(freq, " %d", s->dyn_ltree[n].Freq);
putc('\n', freq);
fclose(freq);
}
}
#endif
/* Construct the literal and distance trees */
build_tree(s, (tree_desc *)(&(s->l_desc)));
@@ -1117,21 +1134,24 @@ local void compress_block(s, ltree, dtree)
}
/* ===========================================================================
* Set the data type to ASCII or BINARY, using a crude approximation:
* binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
* IN assertion: the fields freq of dyn_ltree are set and the total of all
* frequencies does not exceed 64K (to fit in an int on 16 bit machines).
* 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.
* IN assertion: the fields Freq of dyn_ltree are set.
*/
local void set_data_type(s)
deflate_state *s;
{
int n = 0;
unsigned ascii_freq = 0;
unsigned bin_freq = 0;
while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
s->strm->data_type = bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII;
int n;
for (n = 0; n < 9; 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;
}
/* ===========================================================================