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Diffstat (limited to 'src/lib/libc/stdlib/strtol.c')
| -rw-r--r-- | src/lib/libc/stdlib/strtol.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/src/lib/libc/stdlib/strtol.c b/src/lib/libc/stdlib/strtol.c new file mode 100644 index 0000000000..e4ad557fd5 --- /dev/null +++ b/src/lib/libc/stdlib/strtol.c | |||
| @@ -0,0 +1,150 @@ | |||
| 1 | /*- | ||
| 2 | * Copyright (c) 1990 The Regents of the University of California. | ||
| 3 | * 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 | #if defined(LIBC_SCCS) && !defined(lint) | ||
| 35 | static char *rcsid = "$OpenBSD: strtol.c,v 1.4 1996/08/19 08:33:51 tholo Exp $"; | ||
| 36 | #endif /* LIBC_SCCS and not lint */ | ||
| 37 | |||
| 38 | #include <ctype.h> | ||
| 39 | #include <errno.h> | ||
| 40 | #include <limits.h> | ||
| 41 | #include <stdlib.h> | ||
| 42 | |||
| 43 | |||
| 44 | /* | ||
| 45 | * Convert a string to a long integer. | ||
| 46 | * | ||
| 47 | * Ignores `locale' stuff. Assumes that the upper and lower case | ||
| 48 | * alphabets and digits are each contiguous. | ||
| 49 | */ | ||
| 50 | long | ||
| 51 | strtol(nptr, endptr, base) | ||
| 52 | const char *nptr; | ||
| 53 | char **endptr; | ||
| 54 | register int base; | ||
| 55 | { | ||
| 56 | register const char *s; | ||
| 57 | register long acc, cutoff; | ||
| 58 | register int c; | ||
| 59 | register int neg, any, cutlim; | ||
| 60 | |||
| 61 | /* | ||
| 62 | * Skip white space and pick up leading +/- sign if any. | ||
| 63 | * If base is 0, allow 0x for hex and 0 for octal, else | ||
| 64 | * assume decimal; if base is already 16, allow 0x. | ||
| 65 | */ | ||
| 66 | s = nptr; | ||
| 67 | do { | ||
| 68 | c = (unsigned char) *s++; | ||
| 69 | } while (isspace(c)); | ||
| 70 | if (c == '-') { | ||
| 71 | neg = 1; | ||
| 72 | c = *s++; | ||
| 73 | } else { | ||
| 74 | neg = 0; | ||
| 75 | if (c == '+') | ||
| 76 | c = *s++; | ||
| 77 | } | ||
| 78 | if ((base == 0 || base == 16) && | ||
| 79 | c == '0' && (*s == 'x' || *s == 'X')) { | ||
| 80 | c = s[1]; | ||
| 81 | s += 2; | ||
| 82 | base = 16; | ||
| 83 | } | ||
| 84 | if (base == 0) | ||
| 85 | base = c == '0' ? 8 : 10; | ||
| 86 | |||
| 87 | /* | ||
| 88 | * Compute the cutoff value between legal numbers and illegal | ||
| 89 | * numbers. That is the largest legal value, divided by the | ||
| 90 | * base. An input number that is greater than this value, if | ||
| 91 | * followed by a legal input character, is too big. One that | ||
| 92 | * is equal to this value may be valid or not; the limit | ||
| 93 | * between valid and invalid numbers is then based on the last | ||
| 94 | * digit. For instance, if the range for longs is | ||
| 95 | * [-2147483648..2147483647] and the input base is 10, | ||
| 96 | * cutoff will be set to 214748364 and cutlim to either | ||
| 97 | * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated | ||
| 98 | * a value > 214748364, or equal but the next digit is > 7 (or 8), | ||
| 99 | * the number is too big, and we will return a range error. | ||
| 100 | * | ||
| 101 | * Set any if any `digits' consumed; make it negative to indicate | ||
| 102 | * overflow. | ||
| 103 | */ | ||
| 104 | cutoff = neg ? LONG_MIN : LONG_MAX; | ||
| 105 | cutlim = cutoff % base; | ||
| 106 | cutoff /= base; | ||
| 107 | if (neg) { | ||
| 108 | if (cutlim > 0) { | ||
| 109 | cutlim -= base; | ||
| 110 | cutoff += 1; | ||
| 111 | } | ||
| 112 | cutlim = -cutlim; | ||
| 113 | } | ||
| 114 | for (acc = 0, any = 0;; c = (unsigned char) *s++) { | ||
| 115 | if (isdigit(c)) | ||
| 116 | c -= '0'; | ||
| 117 | else if (isalpha(c)) | ||
| 118 | c -= isupper(c) ? 'A' - 10 : 'a' - 10; | ||
| 119 | else | ||
| 120 | break; | ||
| 121 | if (c >= base) | ||
| 122 | break; | ||
| 123 | if (any < 0) | ||
| 124 | continue; | ||
| 125 | if (neg) { | ||
| 126 | if (acc < cutoff || acc == cutoff && c > cutlim) { | ||
| 127 | any = -1; | ||
| 128 | acc = LONG_MIN; | ||
| 129 | errno = ERANGE; | ||
| 130 | } else { | ||
| 131 | any = 1; | ||
| 132 | acc *= base; | ||
| 133 | acc -= c; | ||
| 134 | } | ||
| 135 | } else { | ||
| 136 | if (acc > cutoff || acc == cutoff && c > cutlim) { | ||
| 137 | any = -1; | ||
| 138 | acc = LONG_MAX; | ||
| 139 | errno = ERANGE; | ||
| 140 | } else { | ||
| 141 | any = 1; | ||
| 142 | acc *= base; | ||
| 143 | acc += c; | ||
| 144 | } | ||
| 145 | } | ||
| 146 | } | ||
| 147 | if (endptr != 0) | ||
| 148 | *endptr = (char *) (any ? s - 1 : nptr); | ||
| 149 | return (acc); | ||
| 150 | } | ||
