strtol.c revision 1.1.4.2
1 1.1.4.2 elad /* $NetBSD: strtol.c,v 1.1.4.2 2006/04/19 02:33:05 elad Exp $ */ 2 1.1.4.2 elad 3 1.1.4.2 elad /*- 4 1.1.4.2 elad * Copyright (c) 1990, 1993 5 1.1.4.2 elad * The Regents of the University of California. All rights reserved. 6 1.1.4.2 elad * 7 1.1.4.2 elad * Redistribution and use in source and binary forms, with or without 8 1.1.4.2 elad * modification, are permitted provided that the following conditions 9 1.1.4.2 elad * are met: 10 1.1.4.2 elad * 1. Redistributions of source code must retain the above copyright 11 1.1.4.2 elad * notice, this list of conditions and the following disclaimer. 12 1.1.4.2 elad * 2. Redistributions in binary form must reproduce the above copyright 13 1.1.4.2 elad * notice, this list of conditions and the following disclaimer in the 14 1.1.4.2 elad * documentation and/or other materials provided with the distribution. 15 1.1.4.2 elad * 3. All advertising materials mentioning features or use of this software 16 1.1.4.2 elad * must display the following acknowledgement: 17 1.1.4.2 elad * This product includes software developed by the University of 18 1.1.4.2 elad * California, Berkeley and its contributors. 19 1.1.4.2 elad * 4. Neither the name of the University nor the names of its contributors 20 1.1.4.2 elad * may be used to endorse or promote products derived from this software 21 1.1.4.2 elad * without specific prior written permission. 22 1.1.4.2 elad * 23 1.1.4.2 elad * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 1.1.4.2 elad * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 1.1.4.2 elad * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 1.1.4.2 elad * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 1.1.4.2 elad * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 1.1.4.2 elad * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 1.1.4.2 elad * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 1.1.4.2 elad * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 1.1.4.2 elad * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 1.1.4.2 elad * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 1.1.4.2 elad * SUCH DAMAGE. 34 1.1.4.2 elad */ 35 1.1.4.2 elad 36 1.1.4.2 elad #include <sys/cdefs.h> 37 1.1.4.2 elad 38 1.1.4.2 elad #if defined(LIBC_SCCS) && !defined(lint) 39 1.1.4.2 elad static char sccsid[] = "@(#)strtol.c 8.1 (Berkeley) 6/4/93"; 40 1.1.4.2 elad #endif /* LIBC_SCCS and not lint */ 41 1.1.4.2 elad 42 1.1.4.2 elad #include <lib/libsa/stand.h> 43 1.1.4.2 elad #include <lib/libkern/libkern.h> 44 1.1.4.2 elad 45 1.1.4.2 elad #include <machine/limits.h> 46 1.1.4.2 elad 47 1.1.4.2 elad #include "bootstrap.h" 48 1.1.4.2 elad 49 1.1.4.2 elad /* 50 1.1.4.2 elad * Convert a string to a long integer. 51 1.1.4.2 elad * 52 1.1.4.2 elad * Ignores `locale' stuff. Assumes that the upper and lower case 53 1.1.4.2 elad * alphabets and digits are each contiguous. 54 1.1.4.2 elad */ 55 1.1.4.2 elad long 56 1.1.4.2 elad strtol(nptr, endptr, base) 57 1.1.4.2 elad const char *nptr; 58 1.1.4.2 elad char **endptr; 59 1.1.4.2 elad int base; 60 1.1.4.2 elad { 61 1.1.4.2 elad const char *s; 62 1.1.4.2 elad unsigned long acc; 63 1.1.4.2 elad unsigned char c; 64 1.1.4.2 elad unsigned long cutoff; 65 1.1.4.2 elad int neg = 0, any, cutlim; 66 1.1.4.2 elad 67 1.1.4.2 elad /* Be sensible about NULL strings */ 68 1.1.4.2 elad if (nptr == NULL) 69 1.1.4.2 elad nptr = ""; 70 1.1.4.2 elad s = nptr; 71 1.1.4.2 elad 72 1.1.4.2 elad /* 73 1.1.4.2 elad * Skip white space and pick up leading +/- sign if any. 74 1.1.4.2 elad * If base is 0, allow 0x for hex and 0 for octal, else 75 1.1.4.2 elad * assume decimal; if base is already 16, allow 0x. 76 1.1.4.2 elad */ 77 1.1.4.2 elad do { 78 1.1.4.2 elad c = *s++; 79 1.1.4.2 elad } while (isspace(c)); 80 1.1.4.2 elad if (c == '-') { 81 1.1.4.2 elad neg = 1; 82 1.1.4.2 elad c = *s++; 83 1.1.4.2 elad } else if (c == '+') 84 1.1.4.2 elad c = *s++; 85 1.1.4.2 elad if ((base == 0 || base == 16) && 86 1.1.4.2 elad c == '0' && (*s == 'x' || *s == 'X')) { 87 1.1.4.2 elad c = s[1]; 88 1.1.4.2 elad s += 2; 89 1.1.4.2 elad base = 16; 90 1.1.4.2 elad } 91 1.1.4.2 elad if (base == 0) 92 1.1.4.2 elad base = c == '0' ? 8 : 10; 93 1.1.4.2 elad 94 1.1.4.2 elad /* 95 1.1.4.2 elad * Compute the cutoff value between legal numbers and illegal 96 1.1.4.2 elad * numbers. That is the largest legal value, divided by the 97 1.1.4.2 elad * base. An input number that is greater than this value, if 98 1.1.4.2 elad * followed by a legal input character, is too big. One that 99 1.1.4.2 elad * is equal to this value may be valid or not; the limit 100 1.1.4.2 elad * between valid and invalid numbers is then based on the last 101 1.1.4.2 elad * digit. For instance, if the range for longs is 102 1.1.4.2 elad * [-2147483648..2147483647] and the input base is 10, 103 1.1.4.2 elad * cutoff will be set to 214748364 and cutlim to either 104 1.1.4.2 elad * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated 105 1.1.4.2 elad * a value > 214748364, or equal but the next digit is > 7 (or 8), 106 1.1.4.2 elad * the number is too big, and we will return a range error. 107 1.1.4.2 elad * 108 1.1.4.2 elad * Set any if any `digits' consumed; make it negative to indicate 109 1.1.4.2 elad * overflow. 110 1.1.4.2 elad */ 111 1.1.4.2 elad cutoff = neg ? -(unsigned long)LONG_MIN : LONG_MAX; 112 1.1.4.2 elad cutlim = cutoff % (unsigned long)base; 113 1.1.4.2 elad cutoff /= (unsigned long)base; 114 1.1.4.2 elad for (acc = 0, any = 0;; c = *s++) { 115 1.1.4.2 elad if (!isascii(c)) 116 1.1.4.2 elad break; 117 1.1.4.2 elad if (isdigit(c)) 118 1.1.4.2 elad c -= '0'; 119 1.1.4.2 elad else if (isalpha(c)) 120 1.1.4.2 elad c -= isupper(c) ? 'A' - 10 : 'a' - 10; 121 1.1.4.2 elad else 122 1.1.4.2 elad break; 123 1.1.4.2 elad if (c >= base) 124 1.1.4.2 elad break; 125 1.1.4.2 elad if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 126 1.1.4.2 elad any = -1; 127 1.1.4.2 elad else { 128 1.1.4.2 elad any = 1; 129 1.1.4.2 elad acc *= base; 130 1.1.4.2 elad acc += c; 131 1.1.4.2 elad } 132 1.1.4.2 elad } 133 1.1.4.2 elad if (any < 0) { 134 1.1.4.2 elad acc = neg ? LONG_MIN : LONG_MAX; 135 1.1.4.2 elad errno = ERANGE; 136 1.1.4.2 elad } else if (neg) 137 1.1.4.2 elad acc = -acc; 138 1.1.4.2 elad if (endptr != 0) 139 1.1.4.2 elad *endptr = (char *)(any ? s - 1 : nptr); 140 1.1.4.2 elad return (acc); 141 1.1.4.2 elad } 142
Indexes created Wed Oct 15 16:09:53 GMT 2025