Mercurial > public > mercurial-scm > hg

annotate contrib/python-zstandard/zstd/common/entropy_common.c @ 37495:b1fb341d8a61

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
zstandard: vendor python-zstandard 0.9.0 This was just released. It features a number of goodies. More info at https://gregoryszorc.com/blog/2018/04/09/release-of-python-zstandard-0.9/. The clang-format ignore list was updated to reflect the new source of files. The project contains a vendored copy of zstandard 1.3.4. The old version was 1.1.3. One of the changes between those versions is that zstandard is now dual licensed BSD + GPLv2 and the patent rights grant has been removed. Good riddance. The API should be backwards compatible. So no changes in core should be needed. However, there were a number of changes in the library that we'll want to adapt to. Those will be addressed in subsequent commits. Differential Revision: https://phab.mercurial-scm.org/D3198
author Gregory Szorc <gregory.szorc@gmail.com>
date Mon, 09 Apr 2018 10:13:29 -0700
parents b54a2984cdd4
children 73fef626dae3
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
1 /*
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
2 Common functions of New Generation Entropy library
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
3 Copyright (C) 2016, Yann Collet.
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
4
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
5 BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
6
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
7 Redistribution and use in source and binary forms, with or without
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
8 modification, are permitted provided that the following conditions are
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
9 met:
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
10
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
11 * Redistributions of source code must retain the above copyright
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
12 notice, this list of conditions and the following disclaimer.
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
13 * Redistributions in binary form must reproduce the above
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
14 copyright notice, this list of conditions and the following disclaimer
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
15 in the documentation and/or other materials provided with the
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
16 distribution.
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
17
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
18 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
19 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
20 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
21 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
22 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
23 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
24 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
25 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
26 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
27 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
28 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
29
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
30 You can contact the author at :
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
31 - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
32 - Public forum : https://groups.google.com/forum/#!forum/lz4c
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
33 *************************************************************************** */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
34
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
35 /* *************************************
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
36 * Dependencies
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
37 ***************************************/
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
38 #include "mem.h"
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
39 #include "error_private.h" /* ERR_*, ERROR */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
40 #define FSE_STATIC_LINKING_ONLY /* FSE_MIN_TABLELOG */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
41 #include "fse.h"
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
42 #define HUF_STATIC_LINKING_ONLY /* HUF_TABLELOG_ABSOLUTEMAX */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
43 #include "huf.h"
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
44
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
45
37495
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
46 /*=== Version ===*/
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
47 unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; }
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
48
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
49
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
50 /*=== Error Management ===*/
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
51 unsigned FSE_isError(size_t code) { return ERR_isError(code); }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
52 const char* FSE_getErrorName(size_t code) { return ERR_getErrorName(code); }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
53
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
54 unsigned HUF_isError(size_t code) { return ERR_isError(code); }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
55 const char* HUF_getErrorName(size_t code) { return ERR_getErrorName(code); }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
56
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
57
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
58 /*-**************************************************************
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
59 * FSE NCount encoding-decoding
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
60 ****************************************************************/
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
61 size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr,
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
62 const void* headerBuffer, size_t hbSize)
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
63 {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
64 const BYTE* const istart = (const BYTE*) headerBuffer;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
65 const BYTE* const iend = istart + hbSize;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
66 const BYTE* ip = istart;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
67 int nbBits;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
68 int remaining;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
69 int threshold;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
70 U32 bitStream;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
71 int bitCount;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
72 unsigned charnum = 0;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
73 int previous0 = 0;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
74
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
75 if (hbSize < 4) return ERROR(srcSize_wrong);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
76 bitStream = MEM_readLE32(ip);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
77 nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
78 if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return ERROR(tableLog_tooLarge);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
79 bitStream >>= 4;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
80 bitCount = 4;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
81 *tableLogPtr = nbBits;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
82 remaining = (1<<nbBits)+1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
83 threshold = 1<<nbBits;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
84 nbBits++;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
85
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
86 while ((remaining>1) & (charnum<=*maxSVPtr)) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
87 if (previous0) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
88 unsigned n0 = charnum;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
89 while ((bitStream & 0xFFFF) == 0xFFFF) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
90 n0 += 24;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
91 if (ip < iend-5) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
92 ip += 2;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
93 bitStream = MEM_readLE32(ip) >> bitCount;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
94 } else {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
95 bitStream >>= 16;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
96 bitCount += 16;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
97 } }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
98 while ((bitStream & 3) == 3) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
99 n0 += 3;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
100 bitStream >>= 2;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
101 bitCount += 2;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
102 }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
103 n0 += bitStream & 3;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
104 bitCount += 2;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
105 if (n0 > *maxSVPtr) return ERROR(maxSymbolValue_tooSmall);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
106 while (charnum < n0) normalizedCounter[charnum++] = 0;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
107 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
108 ip += bitCount>>3;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
109 bitCount &= 7;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
110 bitStream = MEM_readLE32(ip) >> bitCount;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
111 } else {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
112 bitStream >>= 2;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
113 } }
37495
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
114 { int const max = (2*threshold-1) - remaining;
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
115 int count;
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
116
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
117 if ((bitStream & (threshold-1)) < (U32)max) {
37495
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
118 count = bitStream & (threshold-1);
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
119 bitCount += nbBits-1;
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
120 } else {
37495
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
121 count = bitStream & (2*threshold-1);
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
122 if (count >= threshold) count -= max;
37495
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
123 bitCount += nbBits;
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
124 }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
125
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
126 count--; /* extra accuracy */
37495
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
127 remaining -= count < 0 ? -count : count; /* -1 means +1 */
b1fb341d8a61 zstandard: vendor python-zstandard 0.9.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30822
diff changeset
128 normalizedCounter[charnum++] = (short)count;
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
129 previous0 = !count;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
130 while (remaining < threshold) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
131 nbBits--;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
132 threshold >>= 1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
133 }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
134
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
135 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
136 ip += bitCount>>3;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
137 bitCount &= 7;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
138 } else {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
139 bitCount -= (int)(8 * (iend - 4 - ip));
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
140 ip = iend - 4;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
141 }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
142 bitStream = MEM_readLE32(ip) >> (bitCount & 31);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
143 } } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
144 if (remaining != 1) return ERROR(corruption_detected);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
145 if (bitCount > 32) return ERROR(corruption_detected);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
146 *maxSVPtr = charnum-1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
147
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
148 ip += (bitCount+7)>>3;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
149 return ip-istart;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
150 }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
151
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
152
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
153 /*! HUF_readStats() :
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
154 Read compact Huffman tree, saved by HUF_writeCTable().
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
155 `huffWeight` is destination buffer.
30822
b54a2984cdd4 zstd: vendor python-zstandard 0.6.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30434
diff changeset
156 `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32.
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
157 @return : size read from `src` , or an error Code .
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
158 Note : Needed by HUF_readCTable() and HUF_readDTableX?() .
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
159 */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
160 size_t HUF_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats,
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
161 U32* nbSymbolsPtr, U32* tableLogPtr,
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
162 const void* src, size_t srcSize)
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
163 {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
164 U32 weightTotal;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
165 const BYTE* ip = (const BYTE*) src;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
166 size_t iSize;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
167 size_t oSize;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
168
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
169 if (!srcSize) return ERROR(srcSize_wrong);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
170 iSize = ip[0];
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
171 /* memset(huffWeight, 0, hwSize); *//* is not necessary, even though some analyzer complain ... */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
172
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
173 if (iSize >= 128) { /* special header */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
174 oSize = iSize - 127;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
175 iSize = ((oSize+1)/2);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
176 if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
177 if (oSize >= hwSize) return ERROR(corruption_detected);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
178 ip += 1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
179 { U32 n;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
180 for (n=0; n<oSize; n+=2) {
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
181 huffWeight[n] = ip[n/2] >> 4;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
182 huffWeight[n+1] = ip[n/2] & 15;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
183 } } }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
184 else { /* header compressed with FSE (normal case) */
30822
b54a2984cdd4 zstd: vendor python-zstandard 0.6.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30434
diff changeset
185 FSE_DTable fseWorkspace[FSE_DTABLE_SIZE_U32(6)]; /* 6 is max possible tableLog for HUF header (maybe even 5, to be tested) */
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
186 if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
30822
b54a2984cdd4 zstd: vendor python-zstandard 0.6.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30434
diff changeset
187 oSize = FSE_decompress_wksp(huffWeight, hwSize-1, ip+1, iSize, fseWorkspace, 6); /* max (hwSize-1) values decoded, as last one is implied */
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
188 if (FSE_isError(oSize)) return oSize;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
189 }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
190
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
191 /* collect weight stats */
30822
b54a2984cdd4 zstd: vendor python-zstandard 0.6.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30434
diff changeset
192 memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32));
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
193 weightTotal = 0;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
194 { U32 n; for (n=0; n<oSize; n++) {
30822
b54a2984cdd4 zstd: vendor python-zstandard 0.6.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30434
diff changeset
195 if (huffWeight[n] >= HUF_TABLELOG_MAX) return ERROR(corruption_detected);
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
196 rankStats[huffWeight[n]]++;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
197 weightTotal += (1 << huffWeight[n]) >> 1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
198 } }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
199 if (weightTotal == 0) return ERROR(corruption_detected);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
200
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
201 /* get last non-null symbol weight (implied, total must be 2^n) */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
202 { U32 const tableLog = BIT_highbit32(weightTotal) + 1;
30822
b54a2984cdd4 zstd: vendor python-zstandard 0.6.0
Gregory Szorc <gregory.szorc@gmail.com>
parents: 30434
diff changeset
203 if (tableLog > HUF_TABLELOG_MAX) return ERROR(corruption_detected);
30434
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
204 *tableLogPtr = tableLog;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
205 /* determine last weight */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
206 { U32 const total = 1 << tableLog;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
207 U32 const rest = total - weightTotal;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
208 U32 const verif = 1 << BIT_highbit32(rest);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
209 U32 const lastWeight = BIT_highbit32(rest) + 1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
210 if (verif != rest) return ERROR(corruption_detected); /* last value must be a clean power of 2 */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
211 huffWeight[oSize] = (BYTE)lastWeight;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
212 rankStats[lastWeight]++;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
213 } }
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
214
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
215 /* check tree construction validity */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
216 if ((rankStats[1] < 2) || (rankStats[1] & 1)) return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
217
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
218 /* results */
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
219 *nbSymbolsPtr = (U32)(oSize+1);
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
220 return iSize+1;
2e484bdea8c4 zstd: vendor zstd 1.1.1
Gregory Szorc <gregory.szorc@gmail.com>
parents:
diff changeset
221 }