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-rw-r--r--zlib/inftrees.h117
1 files changed, 62 insertions, 55 deletions
diff --git a/zlib/inftrees.h b/zlib/inftrees.h
index 1dbfe53..baa53a0 100644
--- a/zlib/inftrees.h
+++ b/zlib/inftrees.h
@@ -1,55 +1,62 @@
-/* inftrees.h -- header to use inftrees.c
- * Copyright (C) 1995-2003 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
- part of the implementation of the compression library and 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
- */
-
-/* Maximum size of dynamic tree. The maximum found in a long but non-
- exhaustive search was 1004 code structures (850 for length/literals
- and 154 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 1440
-#define MAXD 154
-
-/* Type of code to build for inftable() */
-typedef enum {
- CODES,
- LENS,
- DISTS
-} codetype;
-
-extern int inflate_table OF((codetype type, unsigned short FAR *lens,
- unsigned codes, code FAR * FAR *table,
- unsigned FAR *bits, unsigned short FAR *work));
+/* inftrees.h -- header to use inftrees.c
+ * Copyright (C) 1995-2005, 2010 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
+ part of the implementation of the compression library and 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
+ */
+
+/* Maximum size of the dynamic table. The maximum number of code structures is
+ 1444, which is the sum of 852 for literal/length codes and 592 for distance
+ codes. These values were found by exhaustive searches using the program
+ examples/enough.c found in the zlib distribtution. The arguments to that
+ program are the number of symbols, the initial root table size, and the
+ maximum bit length of a code. "enough 286 9 15" for literal/length codes
+ returns returns 852, and "enough 30 6 15" for distance codes returns 592.
+ The initial root table size (9 or 6) is found in the fifth argument of the
+ inflate_table() calls in inflate.c and infback.c. If the root table size is
+ changed, then these maximum sizes would be need to be recalculated and
+ updated. */
+#define ENOUGH_LENS 852
+#define ENOUGH_DISTS 592
+#define ENOUGH (ENOUGH_LENS+ENOUGH_DISTS)
+
+/* Type of code to build for inflate_table() */
+typedef enum {
+ CODES,
+ LENS,
+ DISTS
+} codetype;
+
+int ZLIB_INTERNAL inflate_table OF((codetype type, unsigned short FAR *lens,
+ unsigned codes, code FAR * FAR *table,
+ unsigned FAR *bits, unsigned short FAR *work));