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Avoid use of uintmax_t in enough.c.

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Mark Adler 2024-07-29 14:30:50 -07:00
parent 3f44e55d5d
commit 164b8e3c9f
1 changed files with 12 additions and 12 deletions
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examples/enough.c
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@ -1,7 +1,7 @@
/* enough.c -- determine the maximum size of inflate's Huffman code tables over /* enough.c -- determine the maximum size of inflate's Huffman code tables over
* all possible valid and complete prefix codes, subject to a length limit. * all possible valid and complete prefix codes, subject to a length limit.
* Copyright (C) 2007, 2008, 2012, 2018 Mark Adler * Copyright (C) 2007, 2008, 2012, 2018, 2024 Mark Adler
* Version 1.5 5 August 2018 Mark Adler * Version 1.6 29 July 2024 Mark Adler
*/ */
/* Version history: /* Version history:
@ -19,6 +19,7 @@
Clean up code indentation Clean up code indentation
1.5 5 Aug 2018 Clean up code style, formatting, and comments 1.5 5 Aug 2018 Clean up code style, formatting, and comments
Show all the codes for the maximum, and only the maximum Show all the codes for the maximum, and only the maximum
1.6 29 Jul 2024 Avoid use of uintmax_t
*/ */
/* /*
@ -88,33 +89,32 @@
need to be examined to cover all of the possible table memory usage cases need to be examined to cover all of the possible table memory usage cases
for the default arguments of 286 symbols limited to 15-bit codes. for the default arguments of 286 symbols limited to 15-bit codes.
Note that the uintmax_t type is used for counting. It is quite easy to Note that unsigned long long is used for counting. It is quite easy to
exceed the capacity of an eight-byte integer with a large number of symbols exceed the capacity of an eight-byte integer with a large number of symbols
and a large maximum code length, so multiple-precision arithmetic would need and a large maximum code length, so multiple-precision arithmetic would need
to replace the integer arithmetic in that case. This program will abort if to replace the integer arithmetic in that case. This program will abort if
an overflow occurs. The big_t type identifies where the counting takes an overflow occurs. The big_t type identifies where the counting takes
place. place.
The uintmax_t type is also used for calculating the number of possible codes The unsigned long long type is also used for calculating the number of
remaining at the maximum length. This limits the maximum code length to the possible codes remaining at the maximum length. This limits the maximum code
number of bits in a long long minus the number of bits needed to represent length to the number of bits in a long long minus the number of bits needed
the symbols in a flat code. The code_t type identifies where the bit-pattern to represent the symbols in a flat code. The code_t type identifies where
counting takes place. the bit-pattern counting takes place.
*/ */
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include <stdarg.h> #include <stdarg.h>
#include <stdint.h>
#include <assert.h> #include <assert.h>
#define local static #define local static
// Special data types. // Special data types.
typedef uintmax_t big_t; // type for code counting typedef unsigned long long big_t; // type for code counting
#define PRIbig "ju" // printf format for big_t #define PRIbig "llu" // printf format for big_t
typedef uintmax_t code_t; // type for bit pattern counting typedef big_t code_t; // type for bit pattern counting
struct tab { // type for been-here check struct tab { // type for been-here check
size_t len; // allocated length of bit vector in octets size_t len; // allocated length of bit vector in octets
char *vec; // allocated bit vector char *vec; // allocated bit vector