1 /* OPENBSD ORIGINAL: lib/libc/stdlib/strtoll.c */ 2 3 /*- 4 * Copyright (c) 1992 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include "includes.h" 33 #ifndef HAVE_STRTOLL 34 35 #if defined(LIBC_SCCS) && !defined(lint) 36 static const char rcsid[] = "$OpenBSD: strtoll.c,v 1.4 2005/03/30 18:51:49 pat Exp $"; 37 #endif /* LIBC_SCCS and not lint */ 38 39 #include <sys/types.h> 40 41 #include <ctype.h> 42 #include <errno.h> 43 #include <limits.h> 44 #include <stdlib.h> 45 46 /* 47 * Convert a string to a long long. 48 * 49 * Ignores `locale' stuff. Assumes that the upper and lower case 50 * alphabets and digits are each contiguous. 51 */ 52 long long 53 strtoll(const char *nptr, char **endptr, int base) 54 { 55 const char *s; 56 long long acc, cutoff; 57 int c; 58 int neg, any, cutlim; 59 60 /* 61 * Skip white space and pick up leading +/- sign if any. 62 * If base is 0, allow 0x for hex and 0 for octal, else 63 * assume decimal; if base is already 16, allow 0x. 64 */ 65 s = nptr; 66 do { 67 c = (unsigned char) *s++; 68 } while (isspace(c)); 69 if (c == '-') { 70 neg = 1; 71 c = *s++; 72 } else { 73 neg = 0; 74 if (c == '+') 75 c = *s++; 76 } 77 if ((base == 0 || base == 16) && 78 c == '0' && (*s == 'x' || *s == 'X')) { 79 c = s[1]; 80 s += 2; 81 base = 16; 82 } 83 if (base == 0) 84 base = c == '0' ? 8 : 10; 85 86 /* 87 * Compute the cutoff value between legal numbers and illegal 88 * numbers. That is the largest legal value, divided by the 89 * base. An input number that is greater than this value, if 90 * followed by a legal input character, is too big. One that 91 * is equal to this value may be valid or not; the limit 92 * between valid and invalid numbers is then based on the last 93 * digit. For instance, if the range for long longs is 94 * [-9223372036854775808..9223372036854775807] and the input base 95 * is 10, cutoff will be set to 922337203685477580 and cutlim to 96 * either 7 (neg==0) or 8 (neg==1), meaning that if we have 97 * accumulated a value > 922337203685477580, or equal but the 98 * next digit is > 7 (or 8), the number is too big, and we will 99 * return a range error. 100 * 101 * Set any if any `digits' consumed; make it negative to indicate 102 * overflow. 103 */ 104 cutoff = neg ? LLONG_MIN : LLONG_MAX; 105 cutlim = cutoff % base; 106 cutoff /= base; 107 if (neg) { 108 if (cutlim > 0) { 109 cutlim -= base; 110 cutoff += 1; 111 } 112 cutlim = -cutlim; 113 } 114 for (acc = 0, any = 0;; c = (unsigned char) *s++) { 115 if (isdigit(c)) 116 c -= '0'; 117 else if (isalpha(c)) 118 c -= isupper(c) ? 'A' - 10 : 'a' - 10; 119 else 120 break; 121 if (c >= base) 122 break; 123 if (any < 0) 124 continue; 125 if (neg) { 126 if (acc < cutoff || (acc == cutoff && c > cutlim)) { 127 any = -1; 128 acc = LLONG_MIN; 129 errno = ERANGE; 130 } else { 131 any = 1; 132 acc *= base; 133 acc -= c; 134 } 135 } else { 136 if (acc > cutoff || (acc == cutoff && c > cutlim)) { 137 any = -1; 138 acc = LLONG_MAX; 139 errno = ERANGE; 140 } else { 141 any = 1; 142 acc *= base; 143 acc += c; 144 } 145 } 146 } 147 if (endptr != 0) 148 *endptr = (char *) (any ? s - 1 : nptr); 149 return (acc); 150 } 151 #endif /* HAVE_STRTOLL */ 152