strtonum.cc (1766B)
1 /* $OpenBSD: strtonum.c,v 1.6 2004/08/03 19:38:01 millert Exp $ */ 2 3 /* 4 * Copyright (c) 2004 Ted Unangst and Todd Miller 5 * All rights reserved. 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <errno.h> 21 #include <limits.h> 22 #include <stdlib.h> 23 24 #define INVALID 1 25 #define TOOSMALL 2 26 #define TOOLARGE 3 27 28 long long 29 strtonum(const char *numstr, long long minval, long long maxval, const char **errstrp) 30 { 31 long long ll = 0; 32 char *ep; 33 int error = 0; 34 struct errval { 35 const char *errstr; 36 int err; 37 } ev[4] = { 38 { NULL, 0 }, 39 { "invalid", EINVAL }, 40 { "too small", ERANGE }, 41 { "too large", ERANGE }, 42 }; 43 44 ev[0].err = errno; 45 errno = 0; 46 if (minval > maxval) 47 error = INVALID; 48 else { 49 ll = strtoll(numstr, &ep, 10); 50 if (numstr == ep || *ep != '\0') 51 error = INVALID; 52 else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval) 53 error = TOOSMALL; 54 else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval) 55 error = TOOLARGE; 56 } 57 if (errstrp != NULL) 58 *errstrp = ev[error].errstr; 59 errno = ev[error].err; 60 if (error) 61 ll = 0; 62 63 return (ll); 64 } 65