/* inftrees.h -- header to use inftrees.c
- * Copyright (C) 1995-2005 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
+ * Copyright (C) 1995-1998 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
subject to change. Applications should only use zlib.h.
*/
-/* Structure for decoding tables. Each entry provides either the
- information needed to do the operation requested by the code that
- indexed that table entry, or it provides a pointer to another
- table that indexes more bits of the code. op indicates whether
- the entry is a pointer to another table, a literal, a length or
- distance, an end-of-block, or an invalid code. For a table
- pointer, the low four bits of op is the number of index bits of
- that table. For a length or distance, the low four bits of op
- is the number of extra bits to get after the code. bits is
- the number of bits in this code or part of the code to drop off
- of the bit buffer. val is the actual byte to output in the case
- of a literal, the base length or distance, or the offset from
- the current table to the next table. Each entry is four bytes. */
-typedef struct {
- unsigned char op; /* operation, extra bits, table bits */
- unsigned char bits; /* bits in this part of the code */
- unsigned short val; /* offset in table or code value */
-} code;
-
-/* op values as set by inflate_table():
- 00000000 - literal
- 0000tttt - table link, tttt != 0 is the number of table index bits
- 0001eeee - length or distance, eeee is the number of extra bits
- 01100000 - end of block
- 01000000 - invalid code
- */
+/* Huffman code lookup table entry--this entry is four bytes for machines
+ that have 16-bit pointers (e.g. PC's in the small or medium model). */
+
+#ifndef _INFTREES_H
+#define _INFTREES_H
+
+typedef struct inflate_huft_s inflate_huft;
+
+struct inflate_huft_s {
+ union {
+ struct {
+ Byte Exop; /* number of extra bits or operation */
+ Byte Bits; /* number of bits in this code or subcode */
+ } what;
+ uInt pad; /* pad structure to a power of 2 (4 bytes for */
+ } word; /* 16-bit, 8 bytes for 32-bit int's) */
+ uInt base; /* literal, length base, distance base,
+ or table offset */
+};
/* Maximum size of dynamic tree. The maximum found in a long but non-
- exhaustive search was 1444 code structures (852 for length/literals
- and 592 for distances, the latter actually the result of an
- exhaustive search). The true maximum is not known, but the value
- below is more than safe. */
-#define ENOUGH 2048
-#define MAXD 592
-
-/* Type of code to build for inftable() */
-typedef enum {
- CODES,
- LENS,
- DISTS
-} codetype;
-
-extern int zlib_inflate_table (codetype type, unsigned short *lens,
- unsigned codes, code **table,
- unsigned *bits, unsigned short *work);
+ exhaustive search was 1004 huft structures (850 for length/literals
+ and 154 for distances, the latter actually the result of an
+ exhaustive search). The actual maximum is not known, but the
+ value below is more than safe. */
+#define MANY 1440
+
+extern int zlib_inflate_trees_bits (
+ uInt *, /* 19 code lengths */
+ uInt *, /* bits tree desired/actual depth */
+ inflate_huft **, /* bits tree result */
+ inflate_huft *, /* space for trees */
+ z_streamp); /* for messages */
+
+extern int zlib_inflate_trees_dynamic (
+ uInt, /* number of literal/length codes */
+ uInt, /* number of distance codes */
+ uInt *, /* that many (total) code lengths */
+ uInt *, /* literal desired/actual bit depth */
+ uInt *, /* distance desired/actual bit depth */
+ inflate_huft **, /* literal/length tree result */
+ inflate_huft **, /* distance tree result */
+ inflate_huft *, /* space for trees */
+ z_streamp); /* for messages */
+
+extern int zlib_inflate_trees_fixed (
+ uInt *, /* literal desired/actual bit depth */
+ uInt *, /* distance desired/actual bit depth */
+ inflate_huft **, /* literal/length tree result */
+ inflate_huft **, /* distance tree result */
+ inflate_huft *, /* space for trees */
+ z_streamp); /* for memory allocation */
+
+#endif /* _INFTREES_H */