1 /* Internal function for converting integers to ASCII.
2    Copyright (C) 1994-2021 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #ifndef _ITOA_H
20 #define _ITOA_H
21 
22 #include <limits.h>
23 
24 /* When long long is different from long, by default, _itoa_word is
25    provided to convert long to ASCII and _itoa is provided to convert
26    long long.  A sysdeps _itoa.h can define _ITOA_NEEDED to 0 and define
27    _ITOA_WORD_TYPE to unsigned long long int to override it so that
28    _itoa_word is changed to convert long long to ASCII and _itoa is
29    mapped to _itoa_word.  */
30 
31 #ifndef _ITOA_NEEDED
32 # define _ITOA_NEEDED		(LONG_MAX != LLONG_MAX)
33 #endif
34 #ifndef _ITOA_WORD_TYPE
35 # define _ITOA_WORD_TYPE	unsigned long int
36 #endif
37 
38 
39 /* Convert VALUE into ASCII in base BASE (2..36).
40    Write backwards starting the character just before BUFLIM.
41    Return the address of the first (left-to-right) character in the number.
42    Use upper case letters iff UPPER_CASE is nonzero.  */
43 
44 extern char *_itoa (unsigned long long int value, char *buflim,
45 		    unsigned int base, int upper_case) attribute_hidden;
46 
47 extern const char _itoa_upper_digits[];
48 extern const char _itoa_lower_digits[];
49 #if IS_IN (libc) || IS_IN (rtld)
50 hidden_proto (_itoa_upper_digits)
51 hidden_proto (_itoa_lower_digits)
52 #endif
53 
54 #if IS_IN (libc)
55 extern char *_itoa_word (_ITOA_WORD_TYPE value, char *buflim,
56 			 unsigned int base,
57 			 int upper_case) attribute_hidden;
58 #else
59 static inline char * __attribute__ ((unused, always_inline))
60 _itoa_word (_ITOA_WORD_TYPE value, char *buflim,
61 	    unsigned int base, int upper_case)
62 {
63   const char *digits = (upper_case
64 			? _itoa_upper_digits
65 			: _itoa_lower_digits);
66 
67   switch (base)
68     {
69 # define SPECIAL(Base)							      \
70     case Base:								      \
71       do								      \
72 	*--buflim = digits[value % Base];				      \
73       while ((value /= Base) != 0);					      \
74       break
75 
76       SPECIAL (10);
77       SPECIAL (16);
78       SPECIAL (8);
79     default:
80       do
81 	*--buflim = digits[value % base];
82       while ((value /= base) != 0);
83     }
84   return buflim;
85 }
86 # undef SPECIAL
87 #endif
88 
89 /* Similar to the _itoa functions, but output starts at buf and pointer
90    after the last written character is returned.  */
91 extern char *_fitoa_word (_ITOA_WORD_TYPE value, char *buf,
92 			  unsigned int base,
93 			  int upper_case) attribute_hidden;
94 extern char *_fitoa (unsigned long long value, char *buf, unsigned int base,
95 		     int upper_case) attribute_hidden;
96 
97 #if !_ITOA_NEEDED
98 /* No need for special long long versions.  */
99 # define _itoa(value, buf, base, upper_case) \
100   _itoa_word (value, buf, base, upper_case)
101 # define _fitoa(value, buf, base, upper_case) \
102   _fitoa_word (value, buf, base, upper_case)
103 #endif
104 
105 #endif	/* itoa.h */
106