1 /*
2 FUNCTION
3    <<strtoll>>, <<strtoll_l>>---string to long long
4 
5 INDEX
6 	strtoll
7 
8 INDEX
9 	strtoll_l
10 
11 INDEX
12 	_strtoll_r
13 
14 SYNOPSIS
15 	#include <stdlib.h>
16         long long strtoll(const char *restrict <[s]>, char **restrict <[ptr]>,
17 			  int <[base]>);
18 
19 	#include <stdlib.h>
20         long long strtoll_l(const char *restrict <[s]>,
21 			    char **restrict <[ptr]>, int <[base]>,
22 			    locale_t <[locale]>);
23 
24         long long _strtoll_r(void *<[reent]>,
25 			     const char *restrict <[s]>,
26 			     char **restrict <[ptr]>, int <[base]>);
27 
28 DESCRIPTION
29 The function <<strtoll>> converts the string <<*<[s]>>> to
30 a <<long long>>. First, it breaks down the string into three parts:
31 leading whitespace, which is ignored; a subject string consisting
32 of characters resembling an integer in the radix specified by <[base]>;
33 and a trailing portion consisting of zero or more unparseable characters,
34 and always including the terminating null character. Then, it attempts
35 to convert the subject string into a <<long long>> and returns the
36 result.
37 
38 If the value of <[base]> is 0, the subject string is expected to look
39 like a normal C integer constant: an optional sign, a possible `<<0x>>'
40 indicating a hexadecimal base, and a number. If <[base]> is between
41 2 and 36, the expected form of the subject is a sequence of letters
42 and digits representing an integer in the radix specified by <[base]>,
43 with an optional plus or minus sign. The letters <<a>>--<<z>> (or,
44 equivalently, <<A>>--<<Z>>) are used to signify values from 10 to 35;
45 only letters whose ascribed values are less than <[base]> are
46 permitted. If <[base]> is 16, a leading <<0x>> is permitted.
47 
48 The subject sequence is the longest initial sequence of the input
49 string that has the expected form, starting with the first
50 non-whitespace character.  If the string is empty or consists entirely
51 of whitespace, or if the first non-whitespace character is not a
52 permissible letter or digit, the subject string is empty.
53 
54 If the subject string is acceptable, and the value of <[base]> is zero,
55 <<strtoll>> attempts to determine the radix from the input string. A
56 string with a leading <<0x>> is treated as a hexadecimal value; a string with
57 a leading 0 and no <<x>> is treated as octal; all other strings are
58 treated as decimal. If <[base]> is between 2 and 36, it is used as the
59 conversion radix, as described above. If the subject string begins with
60 a minus sign, the value is negated. Finally, a pointer to the first
61 character past the converted subject string is stored in <[ptr]>, if
62 <[ptr]> is not <<NULL>>.
63 
64 If the subject string is empty (or not in acceptable form), no conversion
65 is performed and the value of <[s]> is stored in <[ptr]> (if <[ptr]> is
66 not <<NULL>>).
67 
68 <<strtoll_l>> is like <<strtoll>> but performs the conversion based on the
69 locale specified by the locale object locale.  If <[locale]> is
70 LC_GLOBAL_LOCALE or not a valid locale object, the behaviour is undefined.
71 
72 The alternate function <<_strtoll_r>> is a reentrant version.  The
73 extra argument <[reent]> is a pointer to a reentrancy structure.
74 
75 RETURNS
76 <<strtoll>>, <<strtoll_l>> return the converted value, if any. If no
77 conversion was made, 0 is returned.
78 
79 <<strtoll>>, <<strtoll_l>> return <<LONG_LONG_MAX>> or <<LONG_LONG_MIN>>
80 if the magnitude of the converted value is too large, and sets <<errno>>
81 to <<ERANGE>>.
82 
83 PORTABILITY
84 <<strtoll>> is ANSI.
85 <<strtoll_l>> is a GNU extension.
86 
87 No supporting OS subroutines are required.
88 */
89 
90 /*-
91  * Copyright (c) 1990 The Regents of the University of California.
92  * All rights reserved.
93  *
94  * Redistribution and use in source and binary forms, with or without
95  * modification, are permitted provided that the following conditions
96  * are met:
97  * 1. Redistributions of source code must retain the above copyright
98  *    notice, this list of conditions and the following disclaimer.
99  * 2. Redistributions in binary form must reproduce the above copyright
100  *    notice, this list of conditions and the following disclaimer in the
101  *    documentation and/or other materials provided with the distribution.
102  * 3. All advertising materials mentioning features or use of this software
103  *    must display the following acknowledgement:
104  *	This product includes software developed by the University of
105  *	California, Berkeley and its contributors.
106  * 4. Neither the name of the University nor the names of its contributors
107  *    may be used to endorse or promote products derived from this software
108  *    without specific prior written permission.
109  *
110  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
111  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
112  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
113  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
114  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
115  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
116  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
117  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
118  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
119  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
120  * SUCH DAMAGE.
121  */
122 
123 #define _GNU_SOURCE
124 #include <_ansi.h>
125 #include <limits.h>
126 #include <ctype.h>
127 #include <errno.h>
128 #include <stdlib.h>
129 #include "../locale/setlocale.h"
130 
131 /*
132  * Convert a string to a long long integer.
133  */
134 static long long
_strtoll_l(const char * __restrict nptr,char ** __restrict endptr,int base,locale_t loc)135 _strtoll_l (const char *__restrict nptr,
136 	    char **__restrict endptr, int base, locale_t loc)
137 {
138 	register const unsigned char *s = (const unsigned char *)nptr;
139 	register unsigned long long acc;
140 	register int c;
141 	register unsigned long long cutoff;
142 	register int neg = 0, any, cutlim;
143 
144 	/*
145 	 * Skip white space and pick up leading +/- sign if any.
146 	 * If base is 0, allow 0x for hex and 0 for octal, else
147 	 * assume decimal; if base is already 16, allow 0x.
148 	 */
149 	do {
150 		c = *s++;
151 	} while (isspace_l(c, loc));
152 	if (c == '-') {
153 		neg = 1;
154 		c = *s++;
155 	} else if (c == '+')
156 		c = *s++;
157 	if ((base == 0 || base == 16) &&
158 	    c == '0' && (*s == 'x' || *s == 'X')) {
159 		c = s[1];
160 		s += 2;
161 		base = 16;
162 	}
163 	if (base == 0)
164 		base = c == '0' ? 8 : 10;
165 
166 	/*
167 	 * Compute the cutoff value between legal numbers and illegal
168 	 * numbers.  That is the largest legal value, divided by the
169 	 * base.  An input number that is greater than this value, if
170 	 * followed by a legal input character, is too big.  One that
171 	 * is equal to this value may be valid or not; the limit
172 	 * between valid and invalid numbers is then based on the last
173 	 * digit.  For instance, if the range for longs is
174 	 * [-2147483648..2147483647] and the input base is 10,
175 	 * cutoff will be set to 214748364 and cutlim to either
176 	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
177 	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
178 	 * the number is too big, and we will return a range error.
179 	 *
180 	 * Set any if any `digits' consumed; make it negative to indicate
181 	 * overflow.
182 	 */
183 	cutoff = neg ? -(unsigned long long)LONG_LONG_MIN : LONG_LONG_MAX;
184 	cutlim = cutoff % (unsigned long long)base;
185 	cutoff /= (unsigned long long)base;
186 	for (acc = 0, any = 0;; c = *s++) {
187 		if (c >= '0' && c <= '9')
188 			c -= '0';
189 		else if (c >= 'A' && c <= 'Z')
190 			c -= 'A' - 10;
191 		else if (c >= 'a' && c <= 'z')
192 			c -= 'a' - 10;
193 		else
194 			break;
195 		if (c >= base)
196 			break;
197                if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
198 			any = -1;
199 		else {
200 			any = 1;
201 			acc *= base;
202 			acc += c;
203 		}
204 	}
205 	if (any < 0) {
206 		acc = neg ? LONG_LONG_MIN : LONG_LONG_MAX;
207 		__errno_r(rptr) = ERANGE;
208 	} else if (neg)
209 		acc = -acc;
210 	if (endptr != 0)
211 		*endptr = (char *) (any ? (char *)s - 1 : nptr);
212 	return (acc);
213 }
214 
215 #ifndef _REENT_ONLY
216 
217 long long
strtoll_l(const char * __restrict s,char ** __restrict ptr,int base,locale_t loc)218 strtoll_l (const char *__restrict s, char **__restrict ptr, int base,
219 	   locale_t loc)
220 {
221 	return _strtoll_l (s, ptr, base, loc);
222 }
223 
224 long long
strtoll(const char * __restrict s,char ** __restrict ptr,int base)225 strtoll (const char *__restrict s,
226 	char **__restrict ptr,
227 	int base)
228 {
229 	return _strtoll_l (s, ptr, base, __get_current_locale ());
230 }
231 
232 #endif
233