1 /* $OpenBSD: strtoll.c,v 1.6 2005/11/10 10:00:17 espie Exp $ */ 2 /*- 3 * Copyright (c) 1992 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. 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 /* OPENBSD ORIGINAL: lib/libc/stdlib/strtoll.c */ 32 33 #include "includes.h" 34 #ifndef HAVE_STRTOLL 35 36 #include <sys/types.h> 37 38 #include <ctype.h> 39 #include <errno.h> 40 #include <limits.h> 41 #include <stdlib.h> 42 43 /* 44 * Convert a string to a long long. 45 * 46 * Ignores `locale' stuff. Assumes that the upper and lower case 47 * alphabets and digits are each contiguous. 48 */ 49 long long 50 strtoll(const char *nptr, char **endptr, int base) 51 { 52 const char *s; 53 long long acc, cutoff; 54 int c; 55 int neg, any, cutlim; 56 57 /* 58 * Skip white space and pick up leading +/- sign if any. 59 * If base is 0, allow 0x for hex and 0 for octal, else 60 * assume decimal; if base is already 16, allow 0x. 61 */ 62 s = nptr; 63 do { 64 c = (unsigned char) *s++; 65 } while (isspace(c)); 66 if (c == '-') { 67 neg = 1; 68 c = *s++; 69 } else { 70 neg = 0; 71 if (c == '+') 72 c = *s++; 73 } 74 if ((base == 0 || base == 16) && 75 c == '0' && (*s == 'x' || *s == 'X')) { 76 c = s[1]; 77 s += 2; 78 base = 16; 79 } 80 if (base == 0) 81 base = c == '0' ? 8 : 10; 82 83 /* 84 * Compute the cutoff value between legal numbers and illegal 85 * numbers. That is the largest legal value, divided by the 86 * base. An input number that is greater than this value, if 87 * followed by a legal input character, is too big. One that 88 * is equal to this value may be valid or not; the limit 89 * between valid and invalid numbers is then based on the last 90 * digit. For instance, if the range for long longs is 91 * [-9223372036854775808..9223372036854775807] and the input base 92 * is 10, cutoff will be set to 922337203685477580 and cutlim to 93 * either 7 (neg==0) or 8 (neg==1), meaning that if we have 94 * accumulated a value > 922337203685477580, or equal but the 95 * next digit is > 7 (or 8), the number is too big, and we will 96 * return a range error. 97 * 98 * Set any if any `digits' consumed; make it negative to indicate 99 * overflow. 100 */ 101 cutoff = neg ? LLONG_MIN : LLONG_MAX; 102 cutlim = cutoff % base; 103 cutoff /= base; 104 if (neg) { 105 if (cutlim > 0) { 106 cutlim -= base; 107 cutoff += 1; 108 } 109 cutlim = -cutlim; 110 } 111 for (acc = 0, any = 0;; c = (unsigned char) *s++) { 112 if (isdigit(c)) 113 c -= '0'; 114 else if (isalpha(c)) 115 c -= isupper(c) ? 'A' - 10 : 'a' - 10; 116 else 117 break; 118 if (c >= base) 119 break; 120 if (any < 0) 121 continue; 122 if (neg) { 123 if (acc < cutoff || (acc == cutoff && c > cutlim)) { 124 any = -1; 125 acc = LLONG_MIN; 126 errno = ERANGE; 127 } else { 128 any = 1; 129 acc *= base; 130 acc -= c; 131 } 132 } else { 133 if (acc > cutoff || (acc == cutoff && c > cutlim)) { 134 any = -1; 135 acc = LLONG_MAX; 136 errno = ERANGE; 137 } else { 138 any = 1; 139 acc *= base; 140 acc += c; 141 } 142 } 143 } 144 if (endptr != 0) 145 *endptr = (char *) (any ? s - 1 : nptr); 146 return (acc); 147 } 148 #endif /* HAVE_STRTOLL */ 149