1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 35 #include <limits.h> 36 #include <ctype.h> 37 #include <errno.h> 38 #include <stdlib.h> 39 40 #include <errno_private.h> 41 42 43 /* 44 * Convert a string to a long integer. 45 * 46 * Assumes that the upper and lower case 47 * alphabets and digits are each contiguous. 48 */ 49 50 long 51 strtol(const char * __restrict nptr, char ** __restrict endptr, int base) 52 { 53 const char *s; 54 unsigned long acc; 55 char c; 56 unsigned long cutoff; 57 int neg, any, cutlim; 58 59 /* 60 * Skip white space and pick up leading +/- sign if any. 61 * If base is 0, allow 0x for hex and 0 for octal, else 62 * assume decimal; if base is already 16, allow 0x. 63 */ 64 s = nptr; 65 do { 66 c = *s++; 67 } while (isspace((unsigned char)c)); 68 if (c == '-') { 69 neg = 1; 70 c = *s++; 71 } else { 72 neg = 0; 73 if (c == '+') 74 c = *s++; 75 } 76 if ((base == 0 || base == 16) && 77 c == '0' && (*s == 'x' || *s == 'X')) { 78 c = s[1]; 79 s += 2; 80 base = 16; 81 } 82 if (base == 0) 83 base = c == '0' ? 8 : 10; 84 acc = any = 0; 85 if (base < 2 || base > 36) 86 goto noconv; 87 88 /* 89 * Compute the cutoff value between legal numbers and illegal 90 * numbers. That is the largest legal value, divided by the 91 * base. An input number that is greater than this value, if 92 * followed by a legal input character, is too big. One that 93 * is equal to this value may be valid or not; the limit 94 * between valid and invalid numbers is then based on the last 95 * digit. For instance, if the range for longs is 96 * [-2147483648..2147483647] and the input base is 10, 97 * cutoff will be set to 214748364 and cutlim to either 98 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated 99 * a value > 214748364, or equal but the next digit is > 7 (or 8), 100 * the number is too big, and we will return a range error. 101 * 102 * Set 'any' if any `digits' consumed; make it negative to indicate 103 * overflow. 104 */ 105 cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX 106 : LONG_MAX; 107 cutlim = cutoff % base; 108 cutoff /= base; 109 for ( ; ; c = *s++) { 110 if (c >= '0' && c <= '9') 111 c -= '0'; 112 else if (c >= 'A' && c <= 'Z') 113 c -= 'A' - 10; 114 else if (c >= 'a' && c <= 'z') 115 c -= 'a' - 10; 116 else 117 break; 118 if (c >= base) 119 break; 120 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 121 any = -1; 122 else { 123 any = 1; 124 acc *= base; 125 acc += c; 126 } 127 } 128 if (any < 0) { 129 acc = neg ? LONG_MIN : LONG_MAX; 130 __set_errno(ERANGE); 131 } else if (!any) { 132 noconv: 133 __set_errno(EINVAL); 134 } else if (neg) 135 acc = -acc; 136 if (endptr != NULL) 137 *endptr = (char *)(any ? s - 1 : nptr); 138 return (acc); 139 } 140 141 142 long __strtol_internal(const char *number, char **_end, int base, int group); 143 144 long 145 __strtol_internal(const char *number, char **_end, int base, int group) 146 { 147 // ToDo: group is currently not supported! 148 (void)group; 149 150 return strtol(number, _end, base); 151 } 152 153