Annotation of sys/lib/libsa/strtoll.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: strtoll.c,v 1.1 2006/09/18 21:12:57 mpf Exp $ */
! 2: /* Modified strtoll() from stdlib */
! 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 <sys/param.h>
! 33: #include "stand.h"
! 34:
! 35: /*
! 36: * Convert a string to a long long.
! 37: *
! 38: * Ignores `locale' stuff. Assumes that the upper and lower case
! 39: * alphabets and digits are each contiguous.
! 40: */
! 41: long long
! 42: strtoll(const char *nptr, char **endptr, int base)
! 43: {
! 44: const char *s;
! 45: long long acc, cutoff;
! 46: int c;
! 47: int neg, any, cutlim;
! 48:
! 49: /*
! 50: * Skip white space and pick up leading +/- sign if any.
! 51: * If base is 0, allow 0x for hex and 0 for octal, else
! 52: * assume decimal; if base is already 16, allow 0x.
! 53: */
! 54: s = nptr;
! 55: do {
! 56: c = (unsigned char) *s++;
! 57: } while (isspace(c));
! 58: if (c == '-') {
! 59: neg = 1;
! 60: c = *s++;
! 61: } else {
! 62: neg = 0;
! 63: if (c == '+')
! 64: c = *s++;
! 65: }
! 66: if ((base == 0 || base == 16) &&
! 67: c == '0' && (*s == 'x' || *s == 'X')) {
! 68: c = s[1];
! 69: s += 2;
! 70: base = 16;
! 71: }
! 72: if (base == 0)
! 73: base = c == '0' ? 8 : 10;
! 74:
! 75: /*
! 76: * Compute the cutoff value between legal numbers and illegal
! 77: * numbers. That is the largest legal value, divided by the
! 78: * base. An input number that is greater than this value, if
! 79: * followed by a legal input character, is too big. One that
! 80: * is equal to this value may be valid or not; the limit
! 81: * between valid and invalid numbers is then based on the last
! 82: * digit. For instance, if the range for long longs is
! 83: * [-9223372036854775808..9223372036854775807] and the input base
! 84: * is 10, cutoff will be set to 922337203685477580 and cutlim to
! 85: * either 7 (neg==0) or 8 (neg==1), meaning that if we have
! 86: * accumulated a value > 922337203685477580, or equal but the
! 87: * next digit is > 7 (or 8), the number is too big, and we will
! 88: * return a range error.
! 89: *
! 90: * Set any if any `digits' consumed; make it negative to indicate
! 91: * overflow.
! 92: */
! 93: cutoff = neg ? LLONG_MIN : LLONG_MAX;
! 94: cutlim = cutoff % base;
! 95: cutoff /= base;
! 96: if (neg) {
! 97: if (cutlim > 0) {
! 98: cutlim -= base;
! 99: cutoff += 1;
! 100: }
! 101: cutlim = -cutlim;
! 102: }
! 103: for (acc = 0, any = 0;; c = (unsigned char) *s++) {
! 104: if (isdigit(c))
! 105: c -= '0';
! 106: else if (isalpha(c))
! 107: c -= isupper(c) ? 'A' - 10 : 'a' - 10;
! 108: else
! 109: break;
! 110: if (c >= base)
! 111: break;
! 112: if (any < 0)
! 113: continue;
! 114: if (neg) {
! 115: if (acc < cutoff || (acc == cutoff && c > cutlim)) {
! 116: any = -1;
! 117: acc = LLONG_MIN;
! 118: } else {
! 119: any = 1;
! 120: acc *= base;
! 121: acc -= c;
! 122: }
! 123: } else {
! 124: if (acc > cutoff || (acc == cutoff && c > cutlim)) {
! 125: any = -1;
! 126: acc = LLONG_MAX;
! 127: } else {
! 128: any = 1;
! 129: acc *= base;
! 130: acc += c;
! 131: }
! 132: }
! 133: }
! 134: if (endptr != 0)
! 135: *endptr = (char *) (any ? s - 1 : nptr);
! 136: return (acc);
! 137: }
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