1 /*-
2  * Copyright (c) 2014 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. [rescinded 22 July 1999]
14  * 4. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32 
33 @deftypefn Supplemental {long long int} strtoll (const char *@var{string}, @
34   char **@var{endptr}, int @var{base})
35 @deftypefnx Supplemental {unsigned long long int} strtoul (@
36   const char *@var{string}, char **@var{endptr}, int @var{base})
37 
38 The @code{strtoll} function converts the string in @var{string} to a
39 long long integer value according to the given @var{base}, which must be
40 between 2 and 36 inclusive, or be the special value 0.  If @var{base}
41 is 0, @code{strtoll} will look for the prefixes @code{0} and @code{0x}
42 to indicate bases 8 and 16, respectively, else default to base 10.
43 When the base is 16 (either explicitly or implicitly), a prefix of
44 @code{0x} is allowed.  The handling of @var{endptr} is as that of
45 @code{strtod} above.  The @code{strtoull} function is the same, except
46 that the converted value is unsigned.
47 
48 @end deftypefn
49 
50 */
51 
52 #ifdef HAVE_CONFIG_H
53 #include "config.h"
54 #endif
55 #ifdef HAVE_LIMITS_H
56 #include <limits.h>
57 #endif
58 #ifdef HAVE_SYS_PARAM_H
59 #include <sys/param.h>
60 #endif
61 #include <errno.h>
62 #ifdef NEED_DECLARATION_ERRNO
63 extern int errno;
64 #endif
65 #include "safe-ctype.h"
66 
67 #ifdef HAVE_LONG_LONG
68 
69 __extension__
70 typedef unsigned long long ullong_type;
71 
72 __extension__
73 typedef long long llong_type;
74 
75 /* FIXME: It'd be nice to configure around these, but the include files are too
76    painful.  These macros should at least be more portable than hardwired hex
77    constants. */
78 
79 #ifndef ULLONG_MAX
80 #define ULLONG_MAX (~(ullong_type)0) /* 0xFFFFFFFFFFFFFFFF */
81 #endif
82 
83 #ifndef LLONG_MAX
84 #define LLONG_MAX ((llong_type)(ULLONG_MAX >> 1)) /* 0x7FFFFFFFFFFFFFFF */
85 #endif
86 
87 #ifndef LLONG_MIN
88 #define LLONG_MIN (~LLONG_MAX) /* 0x8000000000000000 */
89 #endif
90 
91 /*
92  * Convert a string to a long long integer.
93  *
94  * Ignores `locale' stuff.  Assumes that the upper and lower case
95  * alphabets and digits are each contiguous.
96  */
97 llong_type
strtoll(const char * nptr,char ** endptr,register int base)98 strtoll(const char *nptr, char **endptr, register int base)
99 {
100 	register const char *s = nptr;
101 	register ullong_type acc;
102 	register int c;
103 	register ullong_type cutoff;
104 	register int neg = 0, any, cutlim;
105 
106 	/*
107 	 * Skip white space and pick up leading +/- sign if any.
108 	 * If base is 0, allow 0x for hex and 0 for octal, else
109 	 * assume decimal; if base is already 16, allow 0x.
110 	 */
111 	do {
112 		c = *s++;
113 	} while (ISSPACE(c));
114 	if (c == '-') {
115 		neg = 1;
116 		c = *s++;
117 	} else if (c == '+')
118 		c = *s++;
119 	if ((base == 0 || base == 16) &&
120 	    c == '0' && (*s == 'x' || *s == 'X')) {
121 		c = s[1];
122 		s += 2;
123 		base = 16;
124 	}
125 	if (base == 0)
126 		base = c == '0' ? 8 : 10;
127 
128 	/*
129 	 * Compute the cutoff value between legal numbers and illegal
130 	 * numbers.  That is the largest legal value, divided by the
131 	 * base.  An input number that is greater than this value, if
132 	 * followed by a legal input character, is too big.  One that
133 	 * is equal to this value may be valid or not; the limit
134 	 * between valid and invalid numbers is then based on the last
135 	 * digit.  For instance, if the range for longs is
136 	 * [-2147483648..2147483647] and the input base is 10,
137 	 * cutoff will be set to 214748364 and cutlim to either
138 	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
139 	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
140 	 * the number is too big, and we will return a range error.
141 	 *
142 	 * Set any if any `digits' consumed; make it negative to indicate
143 	 * overflow.
144 	 */
145 	cutoff = neg ? -(ullong_type)LLONG_MIN : LLONG_MAX;
146 	cutlim = cutoff % (ullong_type)base;
147 	cutoff /= (ullong_type)base;
148 	for (acc = 0, any = 0;; c = *s++) {
149 		if (ISDIGIT(c))
150 			c -= '0';
151 		else if (ISALPHA(c))
152 			c -= ISUPPER(c) ? 'A' - 10 : 'a' - 10;
153 		else
154 			break;
155 		if (c >= base)
156 			break;
157 		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
158 			any = -1;
159 		else {
160 			any = 1;
161 			acc *= base;
162 			acc += c;
163 		}
164 	}
165 	if (any < 0) {
166 		acc = neg ? LLONG_MIN : LLONG_MAX;
167 		errno = ERANGE;
168 	} else if (neg)
169 		acc = -acc;
170 	if (endptr != 0)
171 		*endptr = (char *) (any ? s - 1 : nptr);
172 	return (acc);
173 }
174 
175 #endif /* ifdef HAVE_LONG_LONG */
176