1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Chris Torek. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/ctype.h> 39 #include <sys/limits.h> 40 41 /* 42 * Convert a string to an unsigned quad integer. 43 * 44 * Ignores `locale' stuff. Assumes that the upper and lower case 45 * alphabets and digits are each contiguous. 46 */ 47 u_quad_t 48 strtouq(const char *nptr, char **endptr, int base) 49 { 50 const char *s = nptr; 51 u_quad_t acc; 52 unsigned char c; 53 u_quad_t qbase, cutoff; 54 int neg, any, cutlim; 55 56 /* 57 * See strtoq for comments as to the logic used. 58 */ 59 do { 60 c = *s++; 61 } while (isspace(c)); 62 if (c == '-') { 63 neg = 1; 64 c = *s++; 65 } else { 66 neg = 0; 67 if (c == '+') 68 c = *s++; 69 } 70 if ((base == 0 || base == 16) && 71 c == '0' && (*s == 'x' || *s == 'X')) { 72 c = s[1]; 73 s += 2; 74 base = 16; 75 } 76 if (base == 0) 77 base = c == '0' ? 8 : 10; 78 qbase = (unsigned)base; 79 cutoff = (u_quad_t)UQUAD_MAX / qbase; 80 cutlim = (u_quad_t)UQUAD_MAX % qbase; 81 for (acc = 0, any = 0;; c = *s++) { 82 if (!isascii(c)) 83 break; 84 if (isdigit(c)) 85 c -= '0'; 86 else if (isalpha(c)) 87 c -= isupper(c) ? 'A' - 10 : 'a' - 10; 88 else 89 break; 90 if (c >= base) 91 break; 92 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 93 any = -1; 94 else { 95 any = 1; 96 acc *= qbase; 97 acc += c; 98 } 99 } 100 if (any < 0) { 101 acc = UQUAD_MAX; 102 } else if (neg) 103 acc = -acc; 104 if (endptr != 0) 105 *((const char **)endptr) = any ? s - 1 : nptr; 106 return (acc); 107 } 108