+++ /dev/null
-/*
-# Small Deflate
-`sdefl` is a small bare bone lossless compression library in ANSI C (ISO C90)
-which implements the Deflate (RFC 1951) compressed data format specification standard.
-It is mainly tuned to get as much speed and compression ratio from as little code
-as needed to keep the implementation as concise as possible.
-
-## Features
-- Portable single header and source file duo written in ANSI C (ISO C90)
-- Dual license with either MIT or public domain
-- Small implementation
- - Deflate: 525 LoC
- - Inflate: 320 LoC
-- Webassembly:
- - Deflate ~3.7 KB (~2.2KB compressed)
- - Inflate ~3.6 KB (~2.2KB compressed)
-
-## Usage:
-This file behaves differently depending on what symbols you define
-before including it.
-
-Header-File mode:
-If you do not define `SDEFL_IMPLEMENTATION` before including this file, it
-will operate in header only mode. In this mode it declares all used structs
-and the API of the library without including the implementation of the library.
-
-Implementation mode:
-If you define `SDEFL_IMPLEMENTATION` before including this file, it will
-compile the implementation . Make sure that you only include
-this file implementation in *one* C or C++ file to prevent collisions.
-
-### Benchmark
-
-| Compressor name | Compression| Decompress.| Compr. size | Ratio |
-| ------------------------| -----------| -----------| ----------- | ----- |
-| sdefl 1.0 -0 | 127 MB/s | 233 MB/s | 40004116 | 39.88 |
-| sdefl 1.0 -1 | 111 MB/s | 259 MB/s | 38940674 | 38.82 |
-| sdefl 1.0 -5 | 45 MB/s | 275 MB/s | 36577183 | 36.46 |
-| sdefl 1.0 -7 | 38 MB/s | 276 MB/s | 36523781 | 36.41 |
-| zlib 1.2.11 -1 | 72 MB/s | 307 MB/s | 42298774 | 42.30 |
-| zlib 1.2.11 -6 | 24 MB/s | 313 MB/s | 36548921 | 36.55 |
-| zlib 1.2.11 -9 | 20 MB/s | 314 MB/s | 36475792 | 36.48 |
-| miniz 1.0 -1 | 122 MB/s | 208 MB/s | 48510028 | 48.51 |
-| miniz 1.0 -6 | 27 MB/s | 260 MB/s | 36513697 | 36.51 |
-| miniz 1.0 -9 | 23 MB/s | 261 MB/s | 36460101 | 36.46 |
-| libdeflate 1.3 -1 | 147 MB/s | 667 MB/s | 39597378 | 39.60 |
-| libdeflate 1.3 -6 | 69 MB/s | 689 MB/s | 36648318 | 36.65 |
-| libdeflate 1.3 -9 | 13 MB/s | 672 MB/s | 35197141 | 35.20 |
-| libdeflate 1.3 -12 | 8.13 MB/s | 670 MB/s | 35100568 | 35.10 |
-
-### Compression
-Results on the [Silesia compression corpus](http://sun.aei.polsl.pl/~sdeor/index.php?page=silesia):
-
-| File | Original | `sdefl 0` | `sdefl 5` | `sdefl 7` |
-| :------ | ---------: | -----------------: | ---------: | ----------: |
-| dickens | 10.192.446 | 4,260,187| 3,845,261| 3,833,657 |
-| mozilla | 51.220.480 | 20,774,706 | 19,607,009 | 19,565,867 |
-| mr | 9.970.564 | 3,860,531 | 3,673,460 | 3,665,627 |
-| nci | 33.553.445 | 4,030,283 | 3,094,526 | 3,006,075 |
-| ooffice | 6.152.192 | 3,320,063 | 3,186,373 | 3,183,815 |
-| osdb | 10.085.684 | 3,919,646 | 3,649,510 | 3,649,477 |
-| reymont | 6.627.202 | 2,263,378 | 1,857,588 | 1,827,237 |
-| samba | 21.606.400 | 6,121,797 | 5,462,670 | 5,450,762 |
-| sao | 7.251.944 | 5,612,421 | 5,485,380 | 5,481,765 |
-| webster | 41.458.703 | 13,972,648 | 12,059,432 | 11,991,421 |
-| xml | 5.345.280 | 886,620| 674,009 | 662,141 |
-| x-ray | 8.474.240 | 6,304,655 | 6,244,779 | 6,244,779 |
-
-## License
-```
-------------------------------------------------------------------------------
-This software is available under 2 licenses -- choose whichever you prefer.
-------------------------------------------------------------------------------
-ALTERNATIVE A - MIT License
-Copyright (c) 2020 Micha Mettke
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-of the Software, and to permit persons to whom the Software is furnished to do
-so, subject to the following conditions:
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-------------------------------------------------------------------------------
-ALTERNATIVE B - Public Domain (www.unlicense.org)
-This is free and unencumbered software released into the public domain.
-Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
-software, either in source code form or as a compiled binary, for any purpose,
-commercial or non-commercial, and by any means.
-In jurisdictions that recognize copyright laws, the author or authors of this
-software dedicate any and all copyright interest in the software to the public
-domain. We make this dedication for the benefit of the public at large and to
-the detriment of our heirs and successors. We intend this dedication to be an
-overt act of relinquishment in perpetuity of all present and future rights to
-this software under copyright law.
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
-ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-------------------------------------------------------------------------------
-```
-*/
-#ifndef SDEFL_H_INCLUDED
-#define SDEFL_H_INCLUDED
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#define SDEFL_MAX_OFF (1 << 15)
-#define SDEFL_WIN_SIZ SDEFL_MAX_OFF
-#define SDEFL_WIN_MSK (SDEFL_WIN_SIZ-1)
-
-#define SDEFL_HASH_BITS 15
-#define SDEFL_HASH_SIZ (1 << SDEFL_HASH_BITS)
-#define SDEFL_HASH_MSK (SDEFL_HASH_SIZ-1)
-
-#define SDEFL_MIN_MATCH 4
-#define SDEFL_BLK_MAX (256*1024)
-#define SDEFL_SEQ_SIZ ((SDEFL_BLK_MAX + SDEFL_MIN_MATCH)/SDEFL_MIN_MATCH)
-
-#define SDEFL_SYM_MAX (288)
-#define SDEFL_OFF_MAX (32)
-#define SDEFL_PRE_MAX (19)
-
-#define SDEFL_LVL_MIN 0
-#define SDEFL_LVL_DEF 5
-#define SDEFL_LVL_MAX 8
-
-struct sdefl_freq {
- unsigned lit[SDEFL_SYM_MAX];
- unsigned off[SDEFL_OFF_MAX];
-};
-struct sdefl_code_words {
- unsigned lit[SDEFL_SYM_MAX];
- unsigned off[SDEFL_OFF_MAX];
-};
-struct sdefl_lens {
- unsigned char lit[SDEFL_SYM_MAX];
- unsigned char off[SDEFL_OFF_MAX];
-};
-struct sdefl_codes {
- struct sdefl_code_words word;
- struct sdefl_lens len;
-};
-struct sdefl_seqt {
- int off, len;
-};
-struct sdefl {
- int bits, bitcnt;
- int tbl[SDEFL_HASH_SIZ];
- int prv[SDEFL_WIN_SIZ];
-
- int seq_cnt;
- struct sdefl_seqt seq[SDEFL_SEQ_SIZ];
- struct sdefl_freq freq;
- struct sdefl_codes cod;
-};
-extern int sdefl_bound(int in_len);
-extern int sdeflate(struct sdefl *s, void *o, const void *i, int n, int lvl);
-extern int zsdeflate(struct sdefl *s, void *o, const void *i, int n, int lvl);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* SDEFL_H_INCLUDED */
-
-#ifdef SDEFL_IMPLEMENTATION
-
-#include <assert.h> /* assert */
-#include <string.h> /* memcpy */
-#include <limits.h> /* CHAR_BIT */
-
-#define SDEFL_NIL (-1)
-#define SDEFL_MAX_MATCH 258
-#define SDEFL_MAX_CODE_LEN (15)
-#define SDEFL_SYM_BITS (10u)
-#define SDEFL_SYM_MSK ((1u << SDEFL_SYM_BITS)-1u)
-#define SDEFL_LIT_LEN_CODES (14)
-#define SDEFL_OFF_CODES (15)
-#define SDEFL_PRE_CODES (7)
-#define SDEFL_CNT_NUM(n) ((((n)+3u/4u)+3u)&~3u)
-#define SDEFL_EOB (256)
-
-#define sdefl_npow2(n) (1 << (sdefl_ilog2((n)-1) + 1))
-
-static int
-sdefl_ilog2(int n) {
- if (!n) return 0;
-#ifdef _MSC_VER
- unsigned long msbp = 0;
- _BitScanReverse(&msbp, (unsigned long)n);
- return (int)msbp;
-#elif defined(__GNUC__) || defined(__clang__)
- return (int)sizeof(unsigned long) * CHAR_BIT - 1 - __builtin_clzl((unsigned long)n);
-#else
- #define lt(n) n, n, n, n, n, n, n, n, n, n, n, n, n, n, n, n
- static const char tbl[256] = {
- 0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,lt(4), lt(5), lt(5), lt(6), lt(6), lt(6), lt(6),
- lt(7), lt(7), lt(7), lt(7), lt(7), lt(7), lt(7), lt(7)};
- int tt, t;
- if ((tt = (n >> 16))) {
- return (t = (tt >> 8)) ? 24 + tbl[t] : 16 + tbl[tt];
- } else {
- return (t = (n >> 8)) ? 8 + tbl[t] : tbl[n];
- }
- #undef lt
-#endif
-}
-static unsigned
-sdefl_uload32(const void *p) {
- /* hopefully will be optimized to an unaligned read */
- unsigned n = 0;
- memcpy(&n, p, sizeof(n));
- return n;
-}
-static unsigned
-sdefl_hash32(const void *p) {
- unsigned n = sdefl_uload32(p);
- return (n * 0x9E377989) >> (32 - SDEFL_HASH_BITS);
-}
-static void
-sdefl_put(unsigned char **dst, struct sdefl *s, int code, int bitcnt) {
- s->bits |= (code << s->bitcnt);
- s->bitcnt += bitcnt;
- while (s->bitcnt >= 8) {
- unsigned char *tar = *dst;
- *tar = (unsigned char)(s->bits & 0xFF);
- s->bits >>= 8;
- s->bitcnt -= 8;
- *dst = *dst + 1;
- }
-}
-static void
-sdefl_heap_sub(unsigned A[], unsigned len, unsigned sub) {
- unsigned c, p = sub;
- unsigned v = A[sub];
- while ((c = p << 1) <= len) {
- if (c < len && A[c + 1] > A[c]) c++;
- if (v >= A[c]) break;
- A[p] = A[c], p = c;
- }
- A[p] = v;
-}
-static void
-sdefl_heap_array(unsigned *A, unsigned len) {
- unsigned sub;
- for (sub = len >> 1; sub >= 1; sub--)
- sdefl_heap_sub(A, len, sub);
-}
-static void
-sdefl_heap_sort(unsigned *A, unsigned n) {
- A--;
- sdefl_heap_array(A, n);
- while (n >= 2) {
- unsigned tmp = A[n];
- A[n--] = A[1];
- A[1] = tmp;
- sdefl_heap_sub(A, n, 1);
- }
-}
-static unsigned
-sdefl_sort_sym(unsigned sym_cnt, unsigned *freqs,
- unsigned char *lens, unsigned *sym_out) {
- unsigned cnts[SDEFL_CNT_NUM(SDEFL_SYM_MAX)] = {0};
- unsigned cnt_num = SDEFL_CNT_NUM(sym_cnt);
- unsigned used_sym = 0;
- unsigned sym, i;
- for (sym = 0; sym < sym_cnt; sym++)
- cnts[freqs[sym] < cnt_num-1 ? freqs[sym]: cnt_num-1]++;
- for (i = 1; i < cnt_num; i++) {
- unsigned cnt = cnts[i];
- cnts[i] = used_sym;
- used_sym += cnt;
- }
- for (sym = 0; sym < sym_cnt; sym++) {
- unsigned freq = freqs[sym];
- if (freq) {
- unsigned idx = freq < cnt_num-1 ? freq : cnt_num-1;
- sym_out[cnts[idx]++] = sym | (freq << SDEFL_SYM_BITS);
- } else lens[sym] = 0;
- }
- sdefl_heap_sort(sym_out + cnts[cnt_num-2], cnts[cnt_num-1] - cnts[cnt_num-2]);
- return used_sym;
-}
-static void
-sdefl_build_tree(unsigned *A, unsigned sym_cnt) {
- unsigned i = 0, b = 0, e = 0;
- do {
- unsigned m, n, freq_shift;
- if (i != sym_cnt && (b == e || (A[i] >> SDEFL_SYM_BITS) <= (A[b] >> SDEFL_SYM_BITS)))
- m = i++;
- else m = b++;
- if (i != sym_cnt && (b == e || (A[i] >> SDEFL_SYM_BITS) <= (A[b] >> SDEFL_SYM_BITS)))
- n = i++;
- else n = b++;
-
- freq_shift = (A[m] & ~SDEFL_SYM_MSK) + (A[n] & ~SDEFL_SYM_MSK);
- A[m] = (A[m] & SDEFL_SYM_MSK) | (e << SDEFL_SYM_BITS);
- A[n] = (A[n] & SDEFL_SYM_MSK) | (e << SDEFL_SYM_BITS);
- A[e] = (A[e] & SDEFL_SYM_MSK) | freq_shift;
- } while (sym_cnt - ++e > 1);
-}
-static void
-sdefl_gen_len_cnt(unsigned *A, unsigned root, unsigned *len_cnt,
- unsigned max_code_len) {
- int n;
- unsigned i;
- for (i = 0; i <= max_code_len; i++)
- len_cnt[i] = 0;
- len_cnt[1] = 2;
-
- A[root] &= SDEFL_SYM_MSK;
- for (n = (int)root - 1; n >= 0; n--) {
- unsigned p = A[n] >> SDEFL_SYM_BITS;
- unsigned pdepth = A[p] >> SDEFL_SYM_BITS;
- unsigned depth = pdepth + 1;
- unsigned len = depth;
-
- A[n] = (A[n] & SDEFL_SYM_MSK) | (depth << SDEFL_SYM_BITS);
- if (len >= max_code_len) {
- len = max_code_len;
- do len--; while (!len_cnt[len]);
- }
- len_cnt[len]--;
- len_cnt[len+1] += 2;
- }
-}
-static void
-sdefl_gen_codes(unsigned *A, unsigned char *lens, const unsigned *len_cnt,
- unsigned max_code_word_len, unsigned sym_cnt) {
- unsigned i, sym, len, nxt[SDEFL_MAX_CODE_LEN + 1];
- for (i = 0, len = max_code_word_len; len >= 1; len--) {
- unsigned cnt = len_cnt[len];
- while (cnt--) lens[A[i++] & SDEFL_SYM_MSK] = (unsigned char)len;
- }
- nxt[0] = nxt[1] = 0;
- for (len = 2; len <= max_code_word_len; len++)
- nxt[len] = (nxt[len-1] + len_cnt[len-1]) << 1;
- for (sym = 0; sym < sym_cnt; sym++)
- A[sym] = nxt[lens[sym]]++;
-}
-static unsigned
-sdefl_rev(unsigned c, unsigned char n) {
- c = ((c & 0x5555) << 1) | ((c & 0xAAAA) >> 1);
- c = ((c & 0x3333) << 2) | ((c & 0xCCCC) >> 2);
- c = ((c & 0x0F0F) << 4) | ((c & 0xF0F0) >> 4);
- c = ((c & 0x00FF) << 8) | ((c & 0xFF00) >> 8);
- return c >> (16-n);
-}
-static void
-sdefl_huff(unsigned char *lens, unsigned *codes, unsigned *freqs,
- unsigned num_syms, unsigned max_code_len) {
- unsigned c, *A = codes;
- unsigned len_cnt[SDEFL_MAX_CODE_LEN + 1];
- unsigned used_syms = sdefl_sort_sym(num_syms, freqs, lens, A);
- if (!used_syms) return;
- if (used_syms == 1) {
- unsigned s = A[0] & SDEFL_SYM_MSK;
- unsigned i = s ? s : 1;
- codes[0] = 0, lens[0] = 1;
- codes[i] = 1, lens[i] = 1;
- return;
- }
- sdefl_build_tree(A, used_syms);
- sdefl_gen_len_cnt(A, used_syms-2, len_cnt, max_code_len);
- sdefl_gen_codes(A, lens, len_cnt, max_code_len, num_syms);
- for (c = 0; c < num_syms; c++) {
- codes[c] = sdefl_rev(codes[c], lens[c]);
- }
-}
-struct sdefl_symcnt {
- int items;
- int lit;
- int off;
-};
-static void
-sdefl_precode(struct sdefl_symcnt *cnt, unsigned *freqs, unsigned *items,
- const unsigned char *litlen, const unsigned char *offlen) {
- unsigned *at = items;
- unsigned run_start = 0;
-
- unsigned total = 0;
- unsigned char lens[SDEFL_SYM_MAX + SDEFL_OFF_MAX];
- for (cnt->lit = SDEFL_SYM_MAX; cnt->lit > 257; cnt->lit--)
- if (litlen[cnt->lit - 1]) break;
- for (cnt->off = SDEFL_OFF_MAX; cnt->off > 1; cnt->off--)
- if (offlen[cnt->off - 1]) break;
-
- total = (unsigned)(cnt->lit + cnt->off);
- memcpy(lens, litlen, sizeof(unsigned char) * cnt->lit);
- memcpy(lens + cnt->lit, offlen, sizeof(unsigned char) * cnt->off);
- do {
- unsigned len = lens[run_start];
- unsigned run_end = run_start;
- do run_end++; while (run_end != total && len == lens[run_end]);
- if (!len) {
- while ((run_end - run_start) >= 11) {
- unsigned n = (run_end - run_start) - 11;
- unsigned xbits = n < 0x7f ? n : 0x7f;
- freqs[18]++;
- *at++ = 18u | (xbits << 5u);
- run_start += 11 + xbits;
- }
- if ((run_end - run_start) >= 3) {
- unsigned n = (run_end - run_start) - 3;
- unsigned xbits = n < 0x7 ? n : 0x7;
- freqs[17]++;
- *at++ = 17u | (xbits << 5u);
- run_start += 3 + xbits;
- }
- } else if ((run_end - run_start) >= 4) {
- freqs[len]++;
- *at++ = len;
- run_start++;
- do {
- unsigned xbits = (run_end - run_start) - 3;
- xbits = xbits < 0x03 ? xbits : 0x03;
- *at++ = 16 | (xbits << 5);
- run_start += 3 + xbits;
- freqs[16]++;
- } while ((run_end - run_start) >= 3);
- }
- while (run_start != run_end) {
- freqs[len]++;
- *at++ = len;
- run_start++;
- }
- } while (run_start != total);
- cnt->items = (int)(at - items);
-}
-struct sdefl_match_codes {
- int ls, lc;
- int dc, dx;
-};
-static void
-sdefl_match_codes(struct sdefl_match_codes *cod, int dist, int len) {
- static const short dxmax[] = {0,6,12,24,48,96,192,384,768,1536,3072,6144,12288,24576};
- static const unsigned char lslot[258+1] = {
- 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12,
- 12, 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16,
- 16, 16, 16, 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18,
- 18, 19, 19, 19, 19, 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20,
- 20, 20, 20, 20, 20, 20, 20, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21,
- 21, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22,
- 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
- 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
- 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 25, 25, 25,
- 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
- 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26,
- 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
- 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
- 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
- 27, 27, 28
- };
- cod->ls = lslot[len];
- cod->lc = 257 + cod->ls;
- cod->dx = sdefl_ilog2(sdefl_npow2(dist) >> 2);
- cod->dc = cod->dx ? ((cod->dx + 1) << 1) + (dist > dxmax[cod->dx]) : dist-1;
-}
-static void
-sdefl_match(unsigned char **dst, struct sdefl *s, int dist, int len) {
- static const char lxn[] = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
- static const short lmin[] = {3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,
- 51,59,67,83,99,115,131,163,195,227,258};
- static const short dmin[] = {1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,
- 385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577};
-
- struct sdefl_match_codes cod;
- sdefl_match_codes(&cod, dist, len);
- sdefl_put(dst, s, (int)s->cod.word.lit[cod.lc], s->cod.len.lit[cod.lc]);
- sdefl_put(dst, s, len - lmin[cod.ls], lxn[cod.ls]);
- sdefl_put(dst, s, (int)s->cod.word.off[cod.dc], s->cod.len.off[cod.dc]);
- sdefl_put(dst, s, dist - dmin[cod.dc], cod.dx);
-}
-static void
-sdefl_flush(unsigned char **dst, struct sdefl *s, int is_last,
- const unsigned char *in) {
- int j, i = 0, item_cnt = 0;
- struct sdefl_symcnt symcnt = {0};
- unsigned codes[SDEFL_PRE_MAX];
- unsigned char lens[SDEFL_PRE_MAX];
- unsigned freqs[SDEFL_PRE_MAX] = {0};
- unsigned items[SDEFL_SYM_MAX + SDEFL_OFF_MAX];
- static const unsigned char perm[SDEFL_PRE_MAX] = {16,17,18,0,8,7,9,6,10,5,11,
- 4,12,3,13,2,14,1,15};
-
- /* huffman codes */
- s->freq.lit[SDEFL_EOB]++;
- sdefl_huff(s->cod.len.lit, s->cod.word.lit, s->freq.lit, SDEFL_SYM_MAX, SDEFL_LIT_LEN_CODES);
- sdefl_huff(s->cod.len.off, s->cod.word.off, s->freq.off, SDEFL_OFF_MAX, SDEFL_OFF_CODES);
- sdefl_precode(&symcnt, freqs, items, s->cod.len.lit, s->cod.len.off);
- sdefl_huff(lens, codes, freqs, SDEFL_PRE_MAX, SDEFL_PRE_CODES);
- for (item_cnt = SDEFL_PRE_MAX; item_cnt > 4; item_cnt--) {
- if (lens[perm[item_cnt - 1]]) break;
- }
- /* block header */
- sdefl_put(dst, s, is_last ? 0x01 : 0x00, 1); /* block */
- sdefl_put(dst, s, 0x02, 2); /* dynamic huffman */
- sdefl_put(dst, s, symcnt.lit - 257, 5);
- sdefl_put(dst, s, symcnt.off - 1, 5);
- sdefl_put(dst, s, item_cnt - 4, 4);
- for (i = 0; i < item_cnt; ++i)
- sdefl_put(dst, s, lens[perm[i]], 3);
- for (i = 0; i < symcnt.items; ++i) {
- unsigned sym = items[i] & 0x1F;
- sdefl_put(dst, s, (int)codes[sym], lens[sym]);
- if (sym < 16) continue;
- if (sym == 16) sdefl_put(dst, s, items[i] >> 5, 2);
- else if(sym == 17) sdefl_put(dst, s, items[i] >> 5, 3);
- else sdefl_put(dst, s, items[i] >> 5, 7);
- }
- /* block sequences */
- for (i = 0; i < s->seq_cnt; ++i) {
- if (s->seq[i].off >= 0)
- for (j = 0; j < s->seq[i].len; ++j) {
- int c = in[s->seq[i].off + j];
- sdefl_put(dst, s, (int)s->cod.word.lit[c], s->cod.len.lit[c]);
- }
- else sdefl_match(dst, s, -s->seq[i].off, s->seq[i].len);
- }
- sdefl_put(dst, s, (int)(s)->cod.word.lit[SDEFL_EOB], (s)->cod.len.lit[SDEFL_EOB]);
- memset(&s->freq, 0, sizeof(s->freq));
- s->seq_cnt = 0;
-}
-static void
-sdefl_seq(struct sdefl *s, int off, int len) {
- assert(s->seq_cnt + 2 < SDEFL_SEQ_SIZ);
- s->seq[s->seq_cnt].off = off;
- s->seq[s->seq_cnt].len = len;
- s->seq_cnt++;
-}
-static void
-sdefl_reg_match(struct sdefl *s, int off, int len) {
- struct sdefl_match_codes cod;
- sdefl_match_codes(&cod, off, len);
- s->freq.lit[cod.lc]++;
- s->freq.off[cod.dc]++;
-}
-struct sdefl_match {
- int off;
- int len;
-};
-static void
-sdefl_fnd(struct sdefl_match *m, const struct sdefl *s,
- int chain_len, int max_match, const unsigned char *in, int p) {
- int i = s->tbl[sdefl_hash32(&in[p])];
- int limit = ((p-SDEFL_WIN_SIZ)<SDEFL_NIL)?SDEFL_NIL:(p-SDEFL_WIN_SIZ);
- while (i > limit) {
- if (in[i+m->len] == in[p+m->len] &&
- (sdefl_uload32(&in[i]) == sdefl_uload32(&in[p]))){
- int n = SDEFL_MIN_MATCH;
- while (n < max_match && in[i+n] == in[p+n]) n++;
- if (n > m->len) {
- m->len = n, m->off = p - i;
- if (n == max_match) break;
- }
- }
- if (!(--chain_len)) break;
- i = s->prv[i&SDEFL_WIN_MSK];
- }
-}
-static int
-sdefl_compr(struct sdefl *s, unsigned char *out, const unsigned char *in,
- int in_len, int lvl) {
- unsigned char *q = out;
- static const unsigned char pref[] = {8,10,14,24,30,48,65,96,130};
- int max_chain = (lvl < 8) ? (1 << (lvl + 1)): (1 << 13);
- int n, i = 0, litlen = 0;
- for (n = 0; n < SDEFL_HASH_SIZ; ++n) {
- s->tbl[n] = SDEFL_NIL;
- }
- do {int blk_end = i + SDEFL_BLK_MAX < in_len ? i + SDEFL_BLK_MAX : in_len;
- while (i < blk_end) {
- struct sdefl_match m = {0};
- int max_match = ((in_len-i)>SDEFL_MAX_MATCH) ? SDEFL_MAX_MATCH:(in_len-i);
- int nice_match = pref[lvl] < max_match ? pref[lvl] : max_match;
- int run = 1, inc = 1, run_inc;
- if (max_match > SDEFL_MIN_MATCH) {
- sdefl_fnd(&m, s, max_chain, max_match, in, i);
- }
- if (lvl >= 5 && m.len >= SDEFL_MIN_MATCH && m.len < nice_match){
- struct sdefl_match m2 = {0};
- sdefl_fnd(&m2, s, max_chain, m.len+1, in, i+1);
- m.len = (m2.len > m.len) ? 0 : m.len;
- }
- if (m.len >= SDEFL_MIN_MATCH) {
- if (litlen) {
- sdefl_seq(s, i - litlen, litlen);
- litlen = 0;
- }
- sdefl_seq(s, -m.off, m.len);
- sdefl_reg_match(s, m.off, m.len);
- if (lvl < 2 && m.len >= nice_match) {
- inc = m.len;
- } else {
- run = m.len;
- }
- } else {
- s->freq.lit[in[i]]++;
- litlen++;
- }
- run_inc = run * inc;
- if (in_len - (i + run_inc) > SDEFL_MIN_MATCH) {
- while (run-- > 0) {
- unsigned h = sdefl_hash32(&in[i]);
- s->prv[i&SDEFL_WIN_MSK] = s->tbl[h];
- s->tbl[h] = i, i += inc;
- }
- } else {
- i += run_inc;
- }
- }
- if (litlen) {
- sdefl_seq(s, i - litlen, litlen);
- litlen = 0;
- }
- sdefl_flush(&q, s, blk_end == in_len, in);
- } while (i < in_len);
-
- if (s->bitcnt)
- sdefl_put(&q, s, 0x00, 8 - s->bitcnt);
- return (int)(q - out);
-}
-extern int
-sdeflate(struct sdefl *s, void *out, const void *in, int n, int lvl) {
- s->bits = s->bitcnt = 0;
- return sdefl_compr(s, (unsigned char*)out, (const unsigned char*)in, n, lvl);
-}
-static unsigned
-sdefl_adler32(unsigned adler32, const unsigned char *in, int in_len) {
- #define SDEFL_ADLER_INIT (1)
- const unsigned ADLER_MOD = 65521;
- unsigned s1 = adler32 & 0xffff;
- unsigned s2 = adler32 >> 16;
- unsigned blk_len, i;
-
- blk_len = in_len % 5552;
- while (in_len) {
- for (i = 0; i + 7 < blk_len; i += 8) {
- s1 += in[0]; s2 += s1;
- s1 += in[1]; s2 += s1;
- s1 += in[2]; s2 += s1;
- s1 += in[3]; s2 += s1;
- s1 += in[4]; s2 += s1;
- s1 += in[5]; s2 += s1;
- s1 += in[6]; s2 += s1;
- s1 += in[7]; s2 += s1;
- in += 8;
- }
- for (; i < blk_len; ++i) {
- s1 += *in++, s2 += s1;
- }
- s1 %= ADLER_MOD;
- s2 %= ADLER_MOD;
- in_len -= blk_len;
- blk_len = 5552;
- }
- return (unsigned)(s2 << 16) + (unsigned)s1;
-}
-extern int
-zsdeflate(struct sdefl *s, void *out, const void *in, int n, int lvl) {
- int p = 0;
- unsigned a = 0;
- unsigned char *q = (unsigned char*)out;
-
- s->bits = s->bitcnt = 0;
- sdefl_put(&q, s, 0x78, 8); /* deflate, 32k window */
- sdefl_put(&q, s, 0x01, 8); /* fast compression */
- q += sdefl_compr(s, q, (const unsigned char*)in, n, lvl);
-
- /* append adler checksum */
- a = sdefl_adler32(SDEFL_ADLER_INIT, (const unsigned char*)in, n);
- for (p = 0; p < 4; ++p) {
- sdefl_put(&q, s, (a >> 24) & 0xFF, 8);
- a <<= 8;
- }
- return (int)(q - (unsigned char*)out);
-}
-extern int
-sdefl_bound(int len) {
- int a = 128 + (len * 110) / 100;
- int b = 128 + len + ((len / (31 * 1024)) + 1) * 5;
- return (a > b) ? a : b;
-}
-#endif /* SDEFL_IMPLEMENTATION */
-
projects / pistorm / blobdiff