1 /*-
2  * Copyright (c) 1992 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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 
32 #include <ctype.h>
33 #include <errno.h>
34 #include <limits.h>
35 #include <stdlib.h>
36 #include <inttypes.h>
37 
38 __RCSID("$MirOS: src/lib/libc/stdlib/strtoll.c,v 1.4 2014/03/19 22:54:00 tg Exp $");
39 
40 /*
41  * Convert a string to a long long.
42  *
43  * Ignores `locale' stuff.  Assumes that the upper and lower case
44  * alphabets and digits are each contiguous.
45  */
46 long long
strtoll(const char * nptr,char ** endptr,int base)47 strtoll(const char *nptr, char **endptr, int base)
48 {
49 	const char *s;
50 	long long acc, cutoff;
51 	int c;
52 	int neg, any, cutlim;
53 
54 	/*
55 	 * Skip white space and pick up leading +/- sign if any.
56 	 * If base is 0, allow 0x for hex and 0 for octal, else
57 	 * assume decimal; if base is already 16, allow 0x.
58 	 */
59 	s = nptr;
60 	do {
61 		c = (unsigned char) *s++;
62 	} while (isspace(c));
63 	if (c == '-') {
64 		neg = 1;
65 		c = *s++;
66 	} else {
67 		neg = 0;
68 		if (c == '+')
69 			c = *s++;
70 	}
71 	if ((base == 0 || base == 16) &&
72 	    c == '0' && (*s == 'x' || *s == 'X')) {
73 		c = s[1];
74 		s += 2;
75 		base = 16;
76 	}
77 	if (base == 0)
78 		base = c == '0' ? 8 : 10;
79 
80 	/*
81 	 * Compute the cutoff value between legal numbers and illegal
82 	 * numbers.  That is the largest legal value, divided by the
83 	 * base.  An input number that is greater than this value, if
84 	 * followed by a legal input character, is too big.  One that
85 	 * is equal to this value may be valid or not; the limit
86 	 * between valid and invalid numbers is then based on the last
87 	 * digit.  For instance, if the range for long longs is
88 	 * [-9223372036854775808..9223372036854775807] and the input base
89 	 * is 10, cutoff will be set to 922337203685477580 and cutlim to
90 	 * either 7 (neg==0) or 8 (neg==1), meaning that if we have
91 	 * accumulated a value > 922337203685477580, or equal but the
92 	 * next digit is > 7 (or 8), the number is too big, and we will
93 	 * return a range error.
94 	 *
95 	 * Set any if any `digits' consumed; make it negative to indicate
96 	 * overflow.
97 	 */
98 	cutoff = neg ? LLONG_MIN : LLONG_MAX;
99 	cutlim = cutoff % base;
100 	cutoff /= base;
101 	if (neg) {
102 		if (cutlim > 0) {
103 			cutlim -= base;
104 			cutoff += 1;
105 		}
106 		cutlim = -cutlim;
107 	}
108 	for (acc = 0, any = 0;; c = (unsigned char) *s++) {
109 		if (isdigit(c))
110 			c -= '0';
111 		else if (isalpha(c))
112 			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
113 		else
114 			break;
115 		if (c >= base)
116 			break;
117 		if (any < 0)
118 			continue;
119 		if (neg) {
120 			if (acc < cutoff || (acc == cutoff && c > cutlim)) {
121 				any = -1;
122 				acc = LLONG_MIN;
123 				errno = ERANGE;
124 			} else {
125 				any = 1;
126 				acc *= base;
127 				acc -= c;
128 			}
129 		} else {
130 			if (acc > cutoff || (acc == cutoff && c > cutlim)) {
131 				any = -1;
132 				acc = LLONG_MAX;
133 				errno = ERANGE;
134 			} else {
135 				any = 1;
136 				acc *= base;
137 				acc += c;
138 			}
139 		}
140 	}
141 	if (endptr != 0)
142 		*endptr = (char *) (any ? s - 1 : nptr);
143 	return (acc);
144 }
145 
146 #ifdef __weak_alias
147 __weak_alias(strtoq, strtoll);
148 #else
149 quad_t
strtoq(const char * nptr,char ** endptr,int base)150 strtoq(const char *nptr, char **endptr, int base)
151 {
152         return ((quad_t)strtoll(nptr, endptr, base));
153 }
154 #endif
155 
156 #if ((INTMAX_MIN == LLONG_MIN) && (INTMAX_MAX == LLONG_MAX))
157 #ifdef __weak_alias
158 __weak_alias(strtoimax, strtoll);
159 #else
160 intmax_t
strtoimax(const char * nptr,char ** endptr,int base)161 strtoimax(const char *nptr, char **endptr, int base)
162 {
163         return ((intmax_t)strtoll(nptr, endptr, base));
164 }
165 #endif
166 #endif
167