diff options
Diffstat (limited to 'src/Common/zlib/trees.c')
| -rw-r--r-- | src/Common/zlib/trees.c | 75 |
1 files changed, 27 insertions, 48 deletions
diff --git a/src/Common/zlib/trees.c b/src/Common/zlib/trees.c index 50cf4b45..f73fd99c 100644 --- a/src/Common/zlib/trees.c +++ b/src/Common/zlib/trees.c @@ -1,3 +1,3 @@ /* trees.c -- output deflated data using Huffman coding - * Copyright (C) 1995-2017 Jean-loup Gailly + * Copyright (C) 1995-2021 Jean-loup Gailly * detect_data_type() function provided freely by Cosmin Truta, 2006 @@ -151,3 +151,3 @@ local void compress_block OF((deflate_state *s, const ct_data *ltree, local int detect_data_type OF((deflate_state *s)); -local unsigned bi_reverse OF((unsigned value, int length)); +local unsigned bi_reverse OF((unsigned code, int len)); local void bi_windup OF((deflate_state *s)); @@ -418,3 +418,3 @@ local void init_block(s) s->opt_len = s->static_len = 0L; - s->last_lit = s->matches = 0; + s->sym_next = s->matches = 0; } @@ -872,3 +872,4 @@ void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last) put_short(s, (ush)~stored_len); - zmemcpy(s->pending_buf + s->pending, (Bytef *)buf, stored_len); + if (stored_len) + zmemcpy(s->pending_buf + s->pending, (Bytef *)buf, stored_len); s->pending += stored_len; @@ -949,3 +950,3 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last) opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, - s->last_lit)); + s->sym_next / 3)); @@ -1018,4 +1019,5 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc) { - s->d_buf[s->last_lit] = (ush)dist; - s->l_buf[s->last_lit++] = (uch)lc; + s->sym_buf[s->sym_next++] = dist; + s->sym_buf[s->sym_next++] = dist >> 8; + s->sym_buf[s->sym_next++] = lc; if (dist == 0) { @@ -1034,26 +1036,3 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc) } - -#ifdef TRUNCATE_BLOCK - /* Try to guess if it is profitable to stop the current block here */ - if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { - /* Compute an upper bound for the compressed length */ - ulg out_length = (ulg)s->last_lit*8L; - ulg in_length = (ulg)((long)s->strstart - s->block_start); - int dcode; - for (dcode = 0; dcode < D_CODES; dcode++) { - out_length += (ulg)s->dyn_dtree[dcode].Freq * - (5L+extra_dbits[dcode]); - } - out_length >>= 3; - Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", - s->last_lit, in_length, out_length, - 100L - out_length*100L/in_length)); - if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; - } -#endif - return (s->last_lit == s->lit_bufsize-1); - /* We avoid equality with lit_bufsize because of wraparound at 64K - * on 16 bit machines and because stored blocks are restricted to - * 64K-1 bytes. - */ + return (s->sym_next == s->sym_end); } @@ -1070,3 +1049,3 @@ local void compress_block(s, ltree, dtree) int lc; /* match length or unmatched char (if dist == 0) */ - unsigned lx = 0; /* running index in l_buf */ + unsigned sx = 0; /* running index in sym_buf */ unsigned code; /* the code to send */ @@ -1074,5 +1053,6 @@ local void compress_block(s, ltree, dtree) - if (s->last_lit != 0) do { - dist = s->d_buf[lx]; - lc = s->l_buf[lx++]; + if (s->sym_next != 0) do { + dist = s->sym_buf[sx++] & 0xff; + dist += (unsigned)(s->sym_buf[sx++] & 0xff) << 8; + lc = s->sym_buf[sx++]; if (dist == 0) { @@ -1101,7 +1081,6 @@ local void compress_block(s, ltree, dtree) - /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ - Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, - "pendingBuf overflow"); + /* Check that the overlay between pending_buf and sym_buf is ok: */ + Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow"); - } while (lx < s->last_lit); + } while (sx < s->sym_next); @@ -1114,5 +1093,5 @@ local void compress_block(s, ltree, dtree) * a) There are no non-portable control characters belonging to the - * "black list" (0..6, 14..25, 28..31). + * "block list" (0..6, 14..25, 28..31). * b) There is at least one printable character belonging to the - * "white list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255). + * "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255). * - BINARY otherwise. @@ -1126,3 +1105,3 @@ local int detect_data_type(s) { - /* black_mask is the bit mask of black-listed bytes + /* block_mask is the bit mask of block-listed bytes * set bits 0..6, 14..25, and 28..31 @@ -1130,11 +1109,11 @@ local int detect_data_type(s) */ - unsigned long black_mask = 0xf3ffc07fUL; + unsigned long block_mask = 0xf3ffc07fUL; int n; - /* Check for non-textual ("black-listed") bytes. */ - for (n = 0; n <= 31; n++, black_mask >>= 1) - if ((black_mask & 1) && (s->dyn_ltree[n].Freq != 0)) + /* Check for non-textual ("block-listed") bytes. */ + for (n = 0; n <= 31; n++, block_mask >>= 1) + if ((block_mask & 1) && (s->dyn_ltree[n].Freq != 0)) return Z_BINARY; - /* Check for textual ("white-listed") bytes. */ + /* Check for textual ("allow-listed") bytes. */ if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0 @@ -1146,3 +1125,3 @@ local int detect_data_type(s) - /* There are no "black-listed" or "white-listed" bytes: + /* There are no "block-listed" or "allow-listed" bytes: * this stream either is empty or has tolerated ("gray-listed") bytes only. |