diff options
Diffstat (limited to 'zlib/inftrees.c')
| -rw-r--r-- | zlib/inftrees.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/zlib/inftrees.c b/zlib/inftrees.c index 3bb56398e1c..8a9c13ff03d 100644 --- a/zlib/inftrees.c +++ b/zlib/inftrees.c @@ -1,5 +1,5 @@ /* inftrees.c -- generate Huffman trees for efficient decoding - * Copyright (C) 1995-2003 Mark Adler + * Copyright (C) 1995-2005 Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -9,7 +9,7 @@ #define MAXBITS 15 const char inflate_copyright[] = - " inflate 1.2.1 Copyright 1995-2003 Mark Adler "; + " inflate 1.2.3 Copyright 1995-2005 Mark Adler "; /* 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 @@ -62,7 +62,7 @@ unsigned short FAR *work; 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; static const unsigned short lext[31] = { /* Length codes 257..285 extra */ 16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, - 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 76, 66}; + 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196}; static const unsigned short dbase[32] = { /* Distance codes 0..29 base */ 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, @@ -114,7 +114,15 @@ unsigned short FAR *work; for (max = MAXBITS; max >= 1; max--) if (count[max] != 0) break; if (root > max) root = max; - if (max == 0) return -1; /* no codes! */ + if (max == 0) { /* no symbols to code at all */ + this.op = (unsigned char)64; /* invalid code marker */ + this.bits = (unsigned char)1; + this.val = (unsigned short)0; + *(*table)++ = this; /* make a table to force an error */ + *(*table)++ = this; + *bits = 1; + return 0; /* no symbols, but wait for decoding to report error */ + } for (min = 1; min <= MAXBITS; min++) if (count[min] != 0) break; if (root < min) root = min; @@ -126,7 +134,7 @@ unsigned short FAR *work; left -= count[len]; if (left < 0) return -1; /* over-subscribed */ } - if (left > 0 && (type == CODES || (codes - count[0] != 1))) + if (left > 0 && (type == CODES || max != 1)) return -1; /* incomplete set */ /* generate offsets into symbol table for each length for sorting */ @@ -224,6 +232,7 @@ unsigned short FAR *work; /* replicate for those indices with low len bits equal to huff */ incr = 1U << (len - drop); fill = 1U << curr; + min = fill; /* save offset to next table */ do { fill -= incr; next[(huff >> drop) + fill] = this; @@ -254,7 +263,7 @@ unsigned short FAR *work; drop = root; /* increment past last table */ - next += 1U << curr; + next += min; /* here min is 1 << curr */ /* determine length of next table */ curr = len - drop; @@ -295,7 +304,6 @@ unsigned short FAR *work; drop = 0; len = root; next = *table; - curr = root; this.bits = (unsigned char)len; } |