^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /* +++ trees.c */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /* trees.c -- output deflated data using Huffman coding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 1995-1996 Jean-loup Gailly
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * For conditions of distribution and use, see copyright notice in zlib.h
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * ALGORITHM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * The "deflation" process uses several Huffman trees. The more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * common source values are represented by shorter bit sequences.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * Each code tree is stored in a compressed form which is itself
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * a Huffman encoding of the lengths of all the code strings (in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * ascending order by source values). The actual code strings are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * reconstructed from the lengths in the inflate process, as described
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * in the deflate specification.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * REFERENCES
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * Storer, James A.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * Data Compression: Methods and Theory, pp. 49-50.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * Computer Science Press, 1988. ISBN 0-7167-8156-5.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * Sedgewick, R.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * Algorithms, p290.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * Addison-Wesley, 1983. ISBN 0-201-06672-6.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) /* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) /* #include "deflate.h" */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #include <linux/zutil.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) #include <linux/bitrev.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) #include "defutil.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) #ifdef DEBUG_ZLIB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) # include <ctype.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * Constants
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) #define MAX_BL_BITS 7
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) /* Bit length codes must not exceed MAX_BL_BITS bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) #define END_BLOCK 256
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) /* end of block literal code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) #define REP_3_6 16
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) /* repeat previous bit length 3-6 times (2 bits of repeat count) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) #define REPZ_3_10 17
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) /* repeat a zero length 3-10 times (3 bits of repeat count) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) #define REPZ_11_138 18
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /* repeat a zero length 11-138 times (7 bits of repeat count) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) = {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};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) static const int extra_dbits[D_CODES] /* extra bits for each distance code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) static const uch bl_order[BL_CODES]
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) /* The lengths of the bit length codes are sent in order of decreasing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) * probability, to avoid transmitting the lengths for unused bit length codes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) * Local data. These are initialized only once.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) static ct_data static_ltree[L_CODES+2];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /* The static literal tree. Since the bit lengths are imposed, there is no
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * need for the L_CODES extra codes used during heap construction. However
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) * The codes 286 and 287 are needed to build a canonical tree (see zlib_tr_init
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * below).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) static ct_data static_dtree[D_CODES];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) /* The static distance tree. (Actually a trivial tree since all codes use
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) * 5 bits.)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) static uch dist_code[512];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /* distance codes. The first 256 values correspond to the distances
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) * 3 .. 258, the last 256 values correspond to the top 8 bits of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) * the 15 bit distances.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) static uch length_code[MAX_MATCH-MIN_MATCH+1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) /* length code for each normalized match length (0 == MIN_MATCH) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static int base_length[LENGTH_CODES];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) /* First normalized length for each code (0 = MIN_MATCH) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) static int base_dist[D_CODES];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) /* First normalized distance for each code (0 = distance of 1) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) struct static_tree_desc_s {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) const ct_data *static_tree; /* static tree or NULL */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) const int *extra_bits; /* extra bits for each code or NULL */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) int extra_base; /* base index for extra_bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) int elems; /* max number of elements in the tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) int max_length; /* max bit length for the codes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) static static_tree_desc static_l_desc =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) static static_tree_desc static_d_desc =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) static static_tree_desc static_bl_desc =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) * Local (static) routines in this file.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) static void tr_static_init (void);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) static void init_block (deflate_state *s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) static void pqdownheap (deflate_state *s, ct_data *tree, int k);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) static void gen_bitlen (deflate_state *s, tree_desc *desc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) static void gen_codes (ct_data *tree, int max_code, ush *bl_count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) static void build_tree (deflate_state *s, tree_desc *desc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) static void scan_tree (deflate_state *s, ct_data *tree, int max_code);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) static void send_tree (deflate_state *s, ct_data *tree, int max_code);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) static int build_bl_tree (deflate_state *s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) static void send_all_trees (deflate_state *s, int lcodes, int dcodes,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) int blcodes);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) static void compress_block (deflate_state *s, ct_data *ltree,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) ct_data *dtree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) static void set_data_type (deflate_state *s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) static void bi_flush (deflate_state *s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) static void copy_block (deflate_state *s, char *buf, unsigned len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) int header);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) #ifndef DEBUG_ZLIB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) /* Send a code of the given tree. c and tree must not have side effects */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) #else /* DEBUG_ZLIB */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) # define send_code(s, c, tree) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) send_bits(s, tree[c].Code, tree[c].Len); }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) #define d_code(dist) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) /* Mapping from a distance to a distance code. dist is the distance - 1 and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) * must not have side effects. dist_code[256] and dist_code[257] are never
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) * used.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) * Initialize the various 'constant' tables. In a multi-threaded environment,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) * this function may be called by two threads concurrently, but this is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) * harmless since both invocations do exactly the same thing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) static void tr_static_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) static int static_init_done;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) int n; /* iterates over tree elements */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) int bits; /* bit counter */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) int length; /* length value */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) int code; /* code value */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) int dist; /* distance index */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) ush bl_count[MAX_BITS+1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) /* number of codes at each bit length for an optimal tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) if (static_init_done) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) /* Initialize the mapping length (0..255) -> length code (0..28) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) length = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) for (code = 0; code < LENGTH_CODES-1; code++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) base_length[code] = length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) for (n = 0; n < (1<<extra_lbits[code]); n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) length_code[length++] = (uch)code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) Assert (length == 256, "tr_static_init: length != 256");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) /* Note that the length 255 (match length 258) can be represented
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) * in two different ways: code 284 + 5 bits or code 285, so we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) * overwrite length_code[255] to use the best encoding:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) length_code[length-1] = (uch)code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) dist = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) for (code = 0 ; code < 16; code++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) base_dist[code] = dist;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) for (n = 0; n < (1<<extra_dbits[code]); n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) dist_code[dist++] = (uch)code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) Assert (dist == 256, "tr_static_init: dist != 256");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) dist >>= 7; /* from now on, all distances are divided by 128 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) for ( ; code < D_CODES; code++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) base_dist[code] = dist << 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) dist_code[256 + dist++] = (uch)code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) Assert (dist == 256, "tr_static_init: 256+dist != 512");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) /* Construct the codes of the static literal tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) n = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) /* Codes 286 and 287 do not exist, but we must include them in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) * tree construction to get a canonical Huffman tree (longest code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) * all ones)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) /* The static distance tree is trivial: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) for (n = 0; n < D_CODES; n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) static_dtree[n].Len = 5;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) static_dtree[n].Code = bitrev32((u32)n) >> (32 - 5);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) static_init_done = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) * Initialize the tree data structures for a new zlib stream.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) void zlib_tr_init(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) deflate_state *s
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) tr_static_init();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) s->compressed_len = 0L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) s->l_desc.dyn_tree = s->dyn_ltree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) s->l_desc.stat_desc = &static_l_desc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) s->d_desc.dyn_tree = s->dyn_dtree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) s->d_desc.stat_desc = &static_d_desc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) s->bl_desc.dyn_tree = s->bl_tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) s->bl_desc.stat_desc = &static_bl_desc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) s->bi_buf = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) s->bi_valid = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) s->last_eob_len = 8; /* enough lookahead for inflate */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) #ifdef DEBUG_ZLIB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) s->bits_sent = 0L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) /* Initialize the first block of the first file: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) init_block(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) * Initialize a new block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) static void init_block(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) deflate_state *s
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) int n; /* iterates over tree elements */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) /* Initialize the trees. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) s->dyn_ltree[END_BLOCK].Freq = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) s->opt_len = s->static_len = 0L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) s->last_lit = s->matches = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) #define SMALLEST 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) /* Index within the heap array of least frequent node in the Huffman tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) * Remove the smallest element from the heap and recreate the heap with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) * one less element. Updates heap and heap_len.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) #define pqremove(s, tree, top) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) {\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) top = s->heap[SMALLEST]; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) s->heap[SMALLEST] = s->heap[s->heap_len--]; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) pqdownheap(s, tree, SMALLEST); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) * Compares to subtrees, using the tree depth as tie breaker when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) * the subtrees have equal frequency. This minimizes the worst case length.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) #define smaller(tree, n, m, depth) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) (tree[n].Freq < tree[m].Freq || \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) * Restore the heap property by moving down the tree starting at node k,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) * exchanging a node with the smallest of its two sons if necessary, stopping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) * when the heap property is re-established (each father smaller than its
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) * two sons).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) static void pqdownheap(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) ct_data *tree, /* the tree to restore */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) int k /* node to move down */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) int v = s->heap[k];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) int j = k << 1; /* left son of k */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) while (j <= s->heap_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) /* Set j to the smallest of the two sons: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) if (j < s->heap_len &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) j++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) /* Exit if v is smaller than both sons */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) if (smaller(tree, v, s->heap[j], s->depth)) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) /* Exchange v with the smallest son */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) s->heap[k] = s->heap[j]; k = j;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) /* And continue down the tree, setting j to the left son of k */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) j <<= 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) s->heap[k] = v;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * Compute the optimal bit lengths for a tree and update the total bit length
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) * for the current block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) * IN assertion: the fields freq and dad are set, heap[heap_max] and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) * above are the tree nodes sorted by increasing frequency.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) * OUT assertions: the field len is set to the optimal bit length, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) * array bl_count contains the frequencies for each bit length.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) * The length opt_len is updated; static_len is also updated if stree is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) * not null.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) static void gen_bitlen(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) tree_desc *desc /* the tree descriptor */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) ct_data *tree = desc->dyn_tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) int max_code = desc->max_code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) const ct_data *stree = desc->stat_desc->static_tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) const int *extra = desc->stat_desc->extra_bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) int base = desc->stat_desc->extra_base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) int max_length = desc->stat_desc->max_length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) int h; /* heap index */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) int n, m; /* iterate over the tree elements */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) int bits; /* bit length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) int xbits; /* extra bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) ush f; /* frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) int overflow = 0; /* number of elements with bit length too large */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) /* In a first pass, compute the optimal bit lengths (which may
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) * overflow in the case of the bit length tree).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) n = s->heap[h];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) bits = tree[tree[n].Dad].Len + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) if (bits > max_length) bits = max_length, overflow++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) tree[n].Len = (ush)bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) /* We overwrite tree[n].Dad which is no longer needed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) if (n > max_code) continue; /* not a leaf node */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) s->bl_count[bits]++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) xbits = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) if (n >= base) xbits = extra[n-base];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) f = tree[n].Freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) s->opt_len += (ulg)f * (bits + xbits);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) if (overflow == 0) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) Trace((stderr,"\nbit length overflow\n"));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) /* This happens for example on obj2 and pic of the Calgary corpus */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) /* Find the first bit length which could increase: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) bits = max_length-1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) while (s->bl_count[bits] == 0) bits--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) s->bl_count[bits]--; /* move one leaf down the tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) s->bl_count[max_length]--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) /* The brother of the overflow item also moves one step up,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) * but this does not affect bl_count[max_length]
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) overflow -= 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) } while (overflow > 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) /* Now recompute all bit lengths, scanning in increasing frequency.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) * lengths instead of fixing only the wrong ones. This idea is taken
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) * from 'ar' written by Haruhiko Okumura.)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) for (bits = max_length; bits != 0; bits--) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) n = s->bl_count[bits];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) while (n != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) m = s->heap[--h];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) if (m > max_code) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) if (tree[m].Len != (unsigned) bits) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) s->opt_len += ((long)bits - (long)tree[m].Len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) *(long)tree[m].Freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) tree[m].Len = (ush)bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) n--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) * Generate the codes for a given tree and bit counts (which need not be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) * optimal).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) * IN assertion: the array bl_count contains the bit length statistics for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) * the given tree and the field len is set for all tree elements.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) * OUT assertion: the field code is set for all tree elements of non
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) * zero code length.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) static void gen_codes(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) ct_data *tree, /* the tree to decorate */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) int max_code, /* largest code with non zero frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) ush *bl_count /* number of codes at each bit length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) ush next_code[MAX_BITS+1]; /* next code value for each bit length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) ush code = 0; /* running code value */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) int bits; /* bit index */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) int n; /* code index */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) /* The distribution counts are first used to generate the code values
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) * without bit reversal.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) for (bits = 1; bits <= MAX_BITS; bits++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) next_code[bits] = code = (code + bl_count[bits-1]) << 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) /* Check that the bit counts in bl_count are consistent. The last code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) * must be all ones.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) "inconsistent bit counts");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) for (n = 0; n <= max_code; n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) int len = tree[n].Len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) if (len == 0) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) /* Now reverse the bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) tree[n].Code = bitrev32((u32)(next_code[len]++)) >> (32 - len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) * Construct one Huffman tree and assigns the code bit strings and lengths.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) * Update the total bit length for the current block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) * IN assertion: the field freq is set for all tree elements.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) * OUT assertions: the fields len and code are set to the optimal bit length
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) * and corresponding code. The length opt_len is updated; static_len is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) * also updated if stree is not null. The field max_code is set.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) static void build_tree(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) tree_desc *desc /* the tree descriptor */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) ct_data *tree = desc->dyn_tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) const ct_data *stree = desc->stat_desc->static_tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) int elems = desc->stat_desc->elems;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) int n, m; /* iterate over heap elements */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) int max_code = -1; /* largest code with non zero frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) int node; /* new node being created */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) /* Construct the initial heap, with least frequent element in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) * heap[0] is not used.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) s->heap_len = 0, s->heap_max = HEAP_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) for (n = 0; n < elems; n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) if (tree[n].Freq != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) s->heap[++(s->heap_len)] = max_code = n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) s->depth[n] = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) tree[n].Len = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) /* The pkzip format requires that at least one distance code exists,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) * and that at least one bit should be sent even if there is only one
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) * possible code. So to avoid special checks later on we force at least
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) * two codes of non zero frequency.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) while (s->heap_len < 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) tree[node].Freq = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) s->depth[node] = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) s->opt_len--; if (stree) s->static_len -= stree[node].Len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) /* node is 0 or 1 so it does not have extra bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) desc->max_code = max_code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) * establish sub-heaps of increasing lengths:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) /* Construct the Huffman tree by repeatedly combining the least two
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) * frequent nodes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) node = elems; /* next internal node of the tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) pqremove(s, tree, n); /* n = node of least frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) m = s->heap[SMALLEST]; /* m = node of next least frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) s->heap[--(s->heap_max)] = m;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) /* Create a new node father of n and m */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) tree[node].Freq = tree[n].Freq + tree[m].Freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) s->depth[node] = (uch) (max(s->depth[n], s->depth[m]) + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) tree[n].Dad = tree[m].Dad = (ush)node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) #ifdef DUMP_BL_TREE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) if (tree == s->bl_tree) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) /* and insert the new node in the heap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) s->heap[SMALLEST] = node++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) pqdownheap(s, tree, SMALLEST);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) } while (s->heap_len >= 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) s->heap[--(s->heap_max)] = s->heap[SMALLEST];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) /* At this point, the fields freq and dad are set. We can now
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) * generate the bit lengths.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) gen_bitlen(s, (tree_desc *)desc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) /* The field len is now set, we can generate the bit codes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) gen_codes ((ct_data *)tree, max_code, s->bl_count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) * Scan a literal or distance tree to determine the frequencies of the codes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) * in the bit length tree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) static void scan_tree(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) ct_data *tree, /* the tree to be scanned */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) int max_code /* and its largest code of non zero frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) int n; /* iterates over all tree elements */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) int prevlen = -1; /* last emitted length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) int curlen; /* length of current code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) int nextlen = tree[0].Len; /* length of next code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) int count = 0; /* repeat count of the current code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) int max_count = 7; /* max repeat count */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) int min_count = 4; /* min repeat count */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) if (nextlen == 0) max_count = 138, min_count = 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) tree[max_code+1].Len = (ush)0xffff; /* guard */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) for (n = 0; n <= max_code; n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) curlen = nextlen; nextlen = tree[n+1].Len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) if (++count < max_count && curlen == nextlen) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) } else if (count < min_count) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) s->bl_tree[curlen].Freq += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) } else if (curlen != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) if (curlen != prevlen) s->bl_tree[curlen].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) s->bl_tree[REP_3_6].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) } else if (count <= 10) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) s->bl_tree[REPZ_3_10].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) s->bl_tree[REPZ_11_138].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) count = 0; prevlen = curlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) if (nextlen == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) max_count = 138, min_count = 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) } else if (curlen == nextlen) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) max_count = 6, min_count = 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) max_count = 7, min_count = 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) * Send a literal or distance tree in compressed form, using the codes in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) * bl_tree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) static void send_tree(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) ct_data *tree, /* the tree to be scanned */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) int max_code /* and its largest code of non zero frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) int n; /* iterates over all tree elements */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) int prevlen = -1; /* last emitted length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) int curlen; /* length of current code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) int nextlen = tree[0].Len; /* length of next code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) int count = 0; /* repeat count of the current code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) int max_count = 7; /* max repeat count */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) int min_count = 4; /* min repeat count */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) /* tree[max_code+1].Len = -1; */ /* guard already set */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) if (nextlen == 0) max_count = 138, min_count = 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) for (n = 0; n <= max_code; n++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) curlen = nextlen; nextlen = tree[n+1].Len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) if (++count < max_count && curlen == nextlen) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) } else if (count < min_count) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) } else if (curlen != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) if (curlen != prevlen) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) send_code(s, curlen, s->bl_tree); count--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646) Assert(count >= 3 && count <= 6, " 3_6?");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) } else if (count <= 10) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) count = 0; prevlen = curlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) if (nextlen == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) max_count = 138, min_count = 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) } else if (curlen == nextlen) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) max_count = 6, min_count = 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) max_count = 7, min_count = 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) * Construct the Huffman tree for the bit lengths and return the index in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) * bl_order of the last bit length code to send.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) static int build_bl_tree(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) deflate_state *s
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) int max_blindex; /* index of last bit length code of non zero freq */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) /* Determine the bit length frequencies for literal and distance trees */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) /* Build the bit length tree: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) build_tree(s, (tree_desc *)(&(s->bl_desc)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) /* opt_len now includes the length of the tree representations, except
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) /* Determine the number of bit length codes to send. The pkzip format
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) * requires that at least 4 bit length codes be sent. (appnote.txt says
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) * 3 but the actual value used is 4.)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) /* Update opt_len to include the bit length tree and counts */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) s->opt_len += 3*(max_blindex+1) + 5+5+4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) s->opt_len, s->static_len));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) return max_blindex;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) * Send the header for a block using dynamic Huffman trees: the counts, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) * lengths of the bit length codes, the literal tree and the distance tree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) static void send_all_trees(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) int lcodes, /* number of codes for each tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) int dcodes, /* number of codes for each tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) int blcodes /* number of codes for each tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) int rank; /* index in bl_order */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) "too many codes");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) Tracev((stderr, "\nbl counts: "));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) send_bits(s, dcodes-1, 5);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) for (rank = 0; rank < blcodes; rank++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) * Send a stored block
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) void zlib_tr_stored_block(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) char *buf, /* input block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) ulg stored_len, /* length of input block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) int eof /* true if this is the last block for a file */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) s->compressed_len += (stored_len + 4) << 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) /* Send just the `stored block' type code without any length bytes or data.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) void zlib_tr_stored_type_only(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) deflate_state *s
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) send_bits(s, (STORED_BLOCK << 1), 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) bi_windup(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) s->compressed_len = (s->compressed_len + 3) & ~7L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) * Send one empty static block to give enough lookahead for inflate.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) * This takes 10 bits, of which 7 may remain in the bit buffer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) * The current inflate code requires 9 bits of lookahead. If the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) * last two codes for the previous block (real code plus EOB) were coded
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) * the last real code. In this case we send two empty static blocks instead
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) * of one. (There are no problems if the previous block is stored or fixed.)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) * To simplify the code, we assume the worst case of last real code encoded
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) * on one bit only.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) void zlib_tr_align(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) deflate_state *s
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) send_bits(s, STATIC_TREES<<1, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) send_code(s, END_BLOCK, static_ltree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) bi_flush(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) /* Of the 10 bits for the empty block, we have already sent
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) * (10 - bi_valid) bits. The lookahead for the last real code (before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) * the EOB of the previous block) was thus at least one plus the length
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) * of the EOB plus what we have just sent of the empty static block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) send_bits(s, STATIC_TREES<<1, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) send_code(s, END_BLOCK, static_ltree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) s->compressed_len += 10L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) bi_flush(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) s->last_eob_len = 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) * Determine the best encoding for the current block: dynamic trees, static
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) * trees or store, and output the encoded block to the zip file. This function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) * returns the total compressed length for the file so far.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) ulg zlib_tr_flush_block(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) char *buf, /* input block, or NULL if too old */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) ulg stored_len, /* length of input block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) int eof /* true if this is the last block for a file */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) int max_blindex = 0; /* index of last bit length code of non zero freq */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) /* Build the Huffman trees unless a stored block is forced */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) if (s->level > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) /* Check if the file is ascii or binary */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) if (s->data_type == Z_UNKNOWN) set_data_type(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) /* Construct the literal and distance trees */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) build_tree(s, (tree_desc *)(&(s->l_desc)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) s->static_len));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) build_tree(s, (tree_desc *)(&(s->d_desc)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) s->static_len));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) /* At this point, opt_len and static_len are the total bit lengths of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) * the compressed block data, excluding the tree representations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) /* Build the bit length tree for the above two trees, and get the index
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) * in bl_order of the last bit length code to send.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) max_blindex = build_bl_tree(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) /* Determine the best encoding. Compute first the block length in bytes*/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) opt_lenb = (s->opt_len+3+7)>>3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) static_lenb = (s->static_len+3+7)>>3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839) Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) s->last_lit));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) Assert(buf != (char*)0, "lost buf");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) /* If compression failed and this is the first and last block,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851) * and if the .zip file can be seeked (to rewrite the local header),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) * the whole file is transformed into a stored file:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854) #ifdef STORED_FILE_OK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) # ifdef FORCE_STORED_FILE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856) if (eof && s->compressed_len == 0L) { /* force stored file */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) # else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859) # endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) if (buf == (char*)0) error ("block vanished");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) copy_block(s, buf, (unsigned)stored_len, 0); /* without header */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864) s->compressed_len = stored_len << 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) s->method = STORED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) #endif /* STORED_FILE_OK */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) #ifdef FORCE_STORED
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870) if (buf != (char*)0) { /* force stored block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) if (stored_len+4 <= opt_lenb && buf != (char*)0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873) /* 4: two words for the lengths */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876) * Otherwise we can't have processed more than WSIZE input bytes since
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) * the last block flush, because compression would have been
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879) * transform a block into a stored block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) zlib_tr_stored_block(s, buf, stored_len, eof);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) #ifdef FORCE_STATIC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) } else if (static_lenb >= 0) { /* force static trees */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) } else if (static_lenb == opt_lenb) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) send_bits(s, (STATIC_TREES<<1)+eof, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) s->compressed_len += 3 + s->static_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892) send_bits(s, (DYN_TREES<<1)+eof, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) max_blindex+1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) s->compressed_len += 3 + s->opt_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) Assert (s->compressed_len == s->bits_sent, "bad compressed size");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) init_block(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901) if (eof) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) bi_windup(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) s->compressed_len += 7; /* align on byte boundary */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905) Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) s->compressed_len-7*eof));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) return s->compressed_len >> 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) * Save the match info and tally the frequency counts. Return true if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) * the current block must be flushed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) int zlib_tr_tally(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917) unsigned dist, /* distance of matched string */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) unsigned lc /* match length-MIN_MATCH or unmatched char (if dist==0) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) s->d_buf[s->last_lit] = (ush)dist;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) s->l_buf[s->last_lit++] = (uch)lc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) if (dist == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) /* lc is the unmatched char */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925) s->dyn_ltree[lc].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927) s->matches++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) /* Here, lc is the match length - MIN_MATCH */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) dist--; /* dist = match distance - 1 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930) Assert((ush)dist < (ush)MAX_DIST(s) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) (ush)d_code(dist) < (ush)D_CODES, "zlib_tr_tally: bad match");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) s->dyn_dtree[d_code(dist)].Freq++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) /* Try to guess if it is profitable to stop the current block here */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) if ((s->last_lit & 0xfff) == 0 && s->level > 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) /* Compute an upper bound for the compressed length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) ulg out_length = (ulg)s->last_lit*8L;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) ulg in_length = (ulg)((long)s->strstart - s->block_start);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) int dcode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) for (dcode = 0; dcode < D_CODES; dcode++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) out_length += (ulg)s->dyn_dtree[dcode].Freq *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) (5L+extra_dbits[dcode]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948) out_length >>= 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) s->last_lit, in_length, out_length,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) 100L - out_length*100L/in_length));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) return (s->last_lit == s->lit_bufsize-1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) /* We avoid equality with lit_bufsize because of wraparound at 64K
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956) * on 16 bit machines and because stored blocks are restricted to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) * 64K-1 bytes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) * Send the block data compressed using the given Huffman trees
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) static void compress_block(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) ct_data *ltree, /* literal tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) ct_data *dtree /* distance tree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) unsigned dist; /* distance of matched string */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) int lc; /* match length or unmatched char (if dist == 0) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972) unsigned lx = 0; /* running index in l_buf */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) unsigned code; /* the code to send */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) int extra; /* number of extra bits to send */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976) if (s->last_lit != 0) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) dist = s->d_buf[lx];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) lc = s->l_buf[lx++];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979) if (dist == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980) send_code(s, lc, ltree); /* send a literal byte */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) Tracecv(isgraph(lc), (stderr," '%c' ", lc));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983) /* Here, lc is the match length - MIN_MATCH */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984) code = length_code[lc];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) send_code(s, code+LITERALS+1, ltree); /* send the length code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986) extra = extra_lbits[code];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987) if (extra != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) lc -= base_length[code];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989) send_bits(s, lc, extra); /* send the extra length bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) dist--; /* dist is now the match distance - 1 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) code = d_code(dist);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993) Assert (code < D_CODES, "bad d_code");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) send_code(s, code, dtree); /* send the distance code */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996) extra = extra_dbits[code];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997) if (extra != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998) dist -= base_dist[code];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999) send_bits(s, dist, extra); /* send the extra distance bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) } /* literal or match pair ? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006) } while (lx < s->last_lit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) send_code(s, END_BLOCK, ltree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009) s->last_eob_len = ltree[END_BLOCK].Len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) * Set the data type to ASCII or BINARY, using a crude approximation:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014) * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015) * IN assertion: the fields freq of dyn_ltree are set and the total of all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016) * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018) static void set_data_type(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) deflate_state *s
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022) int n = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) unsigned ascii_freq = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024) unsigned bin_freq = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1025) while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1026) while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1027) while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1028) s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1029) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1030)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1031) /* ===========================================================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1032) * Copy a stored block, storing first the length and its
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1033) * one's complement if requested.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1034) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1035) static void copy_block(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1036) deflate_state *s,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1037) char *buf, /* the input data */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1038) unsigned len, /* its length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1039) int header /* true if block header must be written */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1040) )
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1041) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1042) bi_windup(s); /* align on byte boundary */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1043) s->last_eob_len = 8; /* enough lookahead for inflate */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1044)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1045) if (header) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1046) put_short(s, (ush)len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1047) put_short(s, (ush)~len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1048) #ifdef DEBUG_ZLIB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1049) s->bits_sent += 2*16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1050) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1051) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1052) #ifdef DEBUG_ZLIB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1053) s->bits_sent += (ulg)len<<3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1054) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1055) /* bundle up the put_byte(s, *buf++) calls */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1056) memcpy(&s->pending_buf[s->pending], buf, len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1057) s->pending += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1058) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1059)
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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