From f6194ef39af5864f792412460c354cc339dde7d1 Mon Sep 17 00:00:00 2001 From: Mark Adler Date: Fri, 9 Sep 2011 23:26:40 -0700 Subject: zlib 1.2.3.4 --- deflate.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 55 insertions(+), 20 deletions(-) (limited to 'deflate.c') diff --git a/deflate.c b/deflate.c index fc41b80..db01adf 100644 --- a/deflate.c +++ b/deflate.c @@ -1,5 +1,5 @@ /* deflate.c -- compress data using the deflation algorithm - * Copyright (C) 1995-2006 Jean-loup Gailly. + * Copyright (C) 1995-2009 Jean-loup Gailly. * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -52,7 +52,7 @@ #include "deflate.h" const char deflate_copyright[] = - " deflate 1.2.3.3 Copyright 1995-2006 Jean-loup Gailly "; + " deflate 1.2.3.4 Copyright 1995-2009 Jean-loup Gailly "; /* If you use the zlib library in a product, an acknowledgment is welcome in the documentation of your product. If for some reason you cannot @@ -110,11 +110,6 @@ local void check_match OF((deflate_state *s, IPos start, IPos match, #endif /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ -#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) -/* Minimum amount of lookahead, except at the end of the input file. - * See deflate.c for comments about the MIN_MATCH+1. - */ - /* Values for max_lazy_match, good_match and max_chain_length, depending on * the desired pack level (0..9). The values given below have been tuned to * exclude worst case performance for pathological files. Better values may be @@ -288,6 +283,8 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy, s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); + s->high_water = 0; /* nothing written to s->window yet */ + s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); @@ -332,8 +329,8 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength) strm->adler = adler32(strm->adler, dictionary, dictLength); if (length < MIN_MATCH) return Z_OK; - if (length > MAX_DIST(s)) { - length = MAX_DIST(s); + if (length > s->w_size) { + length = s->w_size; dictionary += dictLength - length; /* use the tail of the dictionary */ } zmemcpy(s->window, dictionary, length); @@ -513,16 +510,16 @@ uLong ZEXPORT deflateBound(strm, sourceLen) break; case 2: /* gzip wrapper */ wraplen = 18; - if (s->gzhead != NULL) { /* user-supplied gzip header */ - if (s->gzhead->extra != NULL) + if (s->gzhead != Z_NULL) { /* user-supplied gzip header */ + if (s->gzhead->extra != Z_NULL) wraplen += 2 + s->gzhead->extra_len; str = s->gzhead->name; - if (str != NULL) + if (str != Z_NULL) do { wraplen++; } while (*str++); str = s->gzhead->comment; - if (str != NULL) + if (str != Z_NULL) do { wraplen++; } while (*str++); @@ -589,7 +586,7 @@ int ZEXPORT deflate (strm, flush) deflate_state *s; if (strm == Z_NULL || strm->state == Z_NULL || - flush > Z_FINISH || flush < 0) { + flush > Z_BLOCK || flush < 0) { return Z_STREAM_ERROR; } s = strm->state; @@ -613,7 +610,7 @@ int ZEXPORT deflate (strm, flush) put_byte(s, 31); put_byte(s, 139); put_byte(s, 8); - if (s->gzhead == NULL) { + if (s->gzhead == Z_NULL) { put_byte(s, 0); put_byte(s, 0); put_byte(s, 0); @@ -640,7 +637,7 @@ int ZEXPORT deflate (strm, flush) (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? 4 : 0)); put_byte(s, s->gzhead->os & 0xff); - if (s->gzhead->extra != NULL) { + if (s->gzhead->extra != Z_NULL) { put_byte(s, s->gzhead->extra_len & 0xff); put_byte(s, (s->gzhead->extra_len >> 8) & 0xff); } @@ -682,7 +679,7 @@ int ZEXPORT deflate (strm, flush) } #ifdef GZIP if (s->status == EXTRA_STATE) { - if (s->gzhead->extra != NULL) { + if (s->gzhead->extra != Z_NULL) { uInt beg = s->pending; /* start of bytes to update crc */ while (s->gzindex < (s->gzhead->extra_len & 0xffff)) { @@ -710,7 +707,7 @@ int ZEXPORT deflate (strm, flush) s->status = NAME_STATE; } if (s->status == NAME_STATE) { - if (s->gzhead->name != NULL) { + if (s->gzhead->name != Z_NULL) { uInt beg = s->pending; /* start of bytes to update crc */ int val; @@ -741,7 +738,7 @@ int ZEXPORT deflate (strm, flush) s->status = COMMENT_STATE; } if (s->status == COMMENT_STATE) { - if (s->gzhead->comment != NULL) { + if (s->gzhead->comment != Z_NULL) { uInt beg = s->pending; /* start of bytes to update crc */ int val; @@ -840,13 +837,17 @@ int ZEXPORT deflate (strm, flush) if (bstate == block_done) { if (flush == Z_PARTIAL_FLUSH) { _tr_align(s); - } else { /* FULL_FLUSH or SYNC_FLUSH */ + } else if (flush != Z_BLOCK) { /* FULL_FLUSH or SYNC_FLUSH */ _tr_stored_block(s, (char*)0, 0L, 0); /* For a full flush, this empty block will be recognized * as a special marker by inflate_sync(). */ if (flush == Z_FULL_FLUSH) { CLEAR_HASH(s); /* forget history */ + if (s->lookahead == 0) { + s->strstart = 0; + s->block_start = 0L; + } } } flush_pending(strm); @@ -1387,6 +1388,40 @@ local void fill_window(s) */ } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); + + /* If the WIN_INIT bytes after the end of the current data have never been + * written, then zero those bytes in order to avoid memory check reports of + * the use of uninitialized (or uninitialised as Julian writes) bytes by + * the longest match routines. Update the high water mark for the next + * time through here. WIN_INIT is set to MAX_MATCH since the longest match + * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead. + */ + if (s->high_water < s->window_size) { + ulg curr = s->strstart + (ulg)(s->lookahead); + ulg init; + + if (s->high_water < curr) { + /* Previous high water mark below current data -- zero WIN_INIT + * bytes or up to end of window, whichever is less. + */ + init = s->window_size - curr; + if (init > WIN_INIT) + init = WIN_INIT; + zmemzero(s->window + curr, (unsigned)init); + s->high_water = curr + init; + } + else if (s->high_water < (ulg)curr + WIN_INIT) { + /* High water mark at or above current data, but below current data + * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up + * to end of window, whichever is less. + */ + init = (ulg)curr + WIN_INIT - s->high_water; + if (init > s->window_size - s->high_water) + init = s->window_size - s->high_water; + zmemzero(s->window + s->high_water, (unsigned)init); + s->high_water += init; + } + } } /* =========================================================================== -- cgit v1.2.3-55-g6feb