Mercurial > repos > blastem

annotate zlib/inftrees.h @ 1971:80920c21bb52

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Add an event log soft flush and call it twice per frame in between hard flushes to netplay latency when there are insufficient hardware updates to flush packets in the middle of a frame
author Michael Pavone <pavone@retrodev.com>
date Fri, 08 May 2020 11:40:30 -0700
parents 00d788dac91a
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
1530
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
1 /* inftrees.h -- header to use inftrees.c
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
2 * Copyright (C) 1995-2005, 2010 Mark Adler
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
3 * For conditions of distribution and use, see copyright notice in zlib.h
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
4 */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
5
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
6 /* WARNING: this file should *not* be used by applications. It is
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
7 part of the implementation of the compression library and is
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
8 subject to change. Applications should only use zlib.h.
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
9 */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
10
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
11 /* Structure for decoding tables. Each entry provides either the
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
12 information needed to do the operation requested by the code that
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
13 indexed that table entry, or it provides a pointer to another
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
14 table that indexes more bits of the code. op indicates whether
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
15 the entry is a pointer to another table, a literal, a length or
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
16 distance, an end-of-block, or an invalid code. For a table
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
17 pointer, the low four bits of op is the number of index bits of
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
18 that table. For a length or distance, the low four bits of op
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
19 is the number of extra bits to get after the code. bits is
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
20 the number of bits in this code or part of the code to drop off
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
21 of the bit buffer. val is the actual byte to output in the case
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
22 of a literal, the base length or distance, or the offset from
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
23 the current table to the next table. Each entry is four bytes. */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
24 typedef struct {
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
25 unsigned char op; /* operation, extra bits, table bits */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
26 unsigned char bits; /* bits in this part of the code */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
27 unsigned short val; /* offset in table or code value */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
28 } code;
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
29
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
30 /* op values as set by inflate_table():
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
31 00000000 - literal
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
32 0000tttt - table link, tttt != 0 is the number of table index bits
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
33 0001eeee - length or distance, eeee is the number of extra bits
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
34 01100000 - end of block
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
35 01000000 - invalid code
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
36 */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
37
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
38 /* Maximum size of the dynamic table. The maximum number of code structures is
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
39 1444, which is the sum of 852 for literal/length codes and 592 for distance
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
40 codes. These values were found by exhaustive searches using the program
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
41 examples/enough.c found in the zlib distribtution. The arguments to that
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
42 program are the number of symbols, the initial root table size, and the
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
43 maximum bit length of a code. "enough 286 9 15" for literal/length codes
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
44 returns returns 852, and "enough 30 6 15" for distance codes returns 592.
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
45 The initial root table size (9 or 6) is found in the fifth argument of the
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
46 inflate_table() calls in inflate.c and infback.c. If the root table size is
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
47 changed, then these maximum sizes would be need to be recalculated and
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
48 updated. */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
49 #define ENOUGH_LENS 852
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
50 #define ENOUGH_DISTS 592
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
51 #define ENOUGH (ENOUGH_LENS+ENOUGH_DISTS)
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
52
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
53 /* Type of code to build for inflate_table() */
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
54 typedef enum {
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
55 CODES,
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
56 LENS,
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
57 DISTS
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
58 } codetype;
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
59
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
60 int ZLIB_INTERNAL inflate_table OF((codetype type, unsigned short FAR *lens,
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
61 unsigned codes, code FAR * FAR *table,
00d788dac91a Added support for reading gzipped ROMs
Michael Pavone <pavone@retrodev.com>
parents:
diff changeset
62 unsigned FAR *bits, unsigned short FAR *work));