summaryrefslogtreecommitdiff
path: root/libiberty/strtoll.c
blob: 37ff8cd3d4c4579cc81572a1cba13b920a4f380e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/*-
 * Copyright (c) 2014 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. [rescinded 22 July 1999]
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*

@deftypefn Supplemental {long long int} strtoll (const char *@var{string}, @
  char **@var{endptr}, int @var{base})
@deftypefnx Supplemental {unsigned long long int} strtoul (@
  const char *@var{string}, char **@var{endptr}, int @var{base})

The @code{strtoll} function converts the string in @var{string} to a
long long integer value according to the given @var{base}, which must be
between 2 and 36 inclusive, or be the special value 0.  If @var{base}
is 0, @code{strtoll} will look for the prefixes @code{0} and @code{0x}
to indicate bases 8 and 16, respectively, else default to base 10.
When the base is 16 (either explicitly or implicitly), a prefix of
@code{0x} is allowed.  The handling of @var{endptr} is as that of
@code{strtod} above.  The @code{strtoull} function is the same, except
that the converted value is unsigned.

@end deftypefn

*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <errno.h>
#ifdef NEED_DECLARATION_ERRNO
extern int errno;
#endif
#include "safe-ctype.h"

#ifdef HAVE_LONG_LONG

__extension__
typedef unsigned long long ullong_type;

__extension__
typedef long long llong_type;

/* FIXME: It'd be nice to configure around these, but the include files are too
   painful.  These macros should at least be more portable than hardwired hex
   constants. */

#ifndef ULLONG_MAX
#define ULLONG_MAX (~(ullong_type)0) /* 0xFFFFFFFFFFFFFFFF */
#endif

#ifndef LLONG_MAX
#define LLONG_MAX ((llong_type)(ULLONG_MAX >> 1)) /* 0x7FFFFFFFFFFFFFFF */
#endif

#ifndef LLONG_MIN
#define LLONG_MIN (~LLONG_MAX) /* 0x8000000000000000 */
#endif

/*
 * Convert a string to a long long integer.
 *
 * Ignores `locale' stuff.  Assumes that the upper and lower case
 * alphabets and digits are each contiguous.
 */
llong_type
strtoll(const char *nptr, char **endptr, register int base)
{
	register const char *s = nptr;
	register ullong_type acc;
	register int c;
	register ullong_type cutoff;
	register int neg = 0, any, cutlim;

	/*
	 * Skip white space and pick up leading +/- sign if any.
	 * If base is 0, allow 0x for hex and 0 for octal, else
	 * assume decimal; if base is already 16, allow 0x.
	 */
	do {
		c = *s++;
	} while (ISSPACE(c));
	if (c == '-') {
		neg = 1;
		c = *s++;
	} else if (c == '+')
		c = *s++;
	if ((base == 0 || base == 16) &&
	    c == '0' && (*s == 'x' || *s == 'X')) {
		c = s[1];
		s += 2;
		base = 16;
	}
	if (base == 0)
		base = c == '0' ? 8 : 10;

	/*
	 * Compute the cutoff value between legal numbers and illegal
	 * numbers.  That is the largest legal value, divided by the
	 * base.  An input number that is greater than this value, if
	 * followed by a legal input character, is too big.  One that
	 * is equal to this value may be valid or not; the limit
	 * between valid and invalid numbers is then based on the last
	 * digit.  For instance, if the range for longs is
	 * [-2147483648..2147483647] and the input base is 10,
	 * cutoff will be set to 214748364 and cutlim to either
	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
	 * the number is too big, and we will return a range error.
	 *
	 * Set any if any `digits' consumed; make it negative to indicate
	 * overflow.
	 */
	cutoff = neg ? -(ullong_type)LLONG_MIN : LLONG_MAX;
	cutlim = cutoff % (ullong_type)base;
	cutoff /= (ullong_type)base;
	for (acc = 0, any = 0;; c = *s++) {
		if (ISDIGIT(c))
			c -= '0';
		else if (ISALPHA(c))
			c -= ISUPPER(c) ? 'A' - 10 : 'a' - 10;
		else
			break;
		if (c >= base)
			break;
		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
			any = -1;
		else {
			any = 1;
			acc *= base;
			acc += c;
		}
	}
	if (any < 0) {
		acc = neg ? LLONG_MIN : LLONG_MAX;
		errno = ERANGE;
	} else if (neg)
		acc = -acc;
	if (endptr != 0)
		*endptr = (char *) (any ? s - 1 : nptr);
	return (acc);
}

#endif /* ifdef HAVE_LONG_LONG */