1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 #if 0 37 static char sccsid[] = "@(#)mystring.c 8.2 (Berkeley) 5/4/95"; 38 #endif 39 #endif /* not lint */ 40 #include <sys/cdefs.h> 41 /* 42 * String functions. 43 * 44 * equal(s1, s2) Return true if strings are equal. 45 * number(s) Convert a string of digits to an integer. 46 * is_number(s) Return true if s is a string of digits. 47 */ 48 49 #include <stdlib.h> 50 #include "shell.h" 51 #include "syntax.h" 52 #include "error.h" 53 #include "mystring.h" 54 55 56 char nullstr[1]; /* zero length string */ 57 58 /* 59 * equal - #defined in mystring.h 60 */ 61 62 63 /* 64 * Convert a string of digits to an integer, printing an error message on 65 * failure. 66 */ 67 68 int 69 number(const char *s) 70 { 71 if (! is_number(s)) 72 error("Illegal number: %s", s); 73 return atoi(s); 74 } 75 76 77 78 /* 79 * Check for a valid number. This should be elsewhere. 80 */ 81 82 int 83 is_number(const char *p) 84 { 85 const char *q; 86 87 if (*p == '\0') 88 return 0; 89 while (*p == '0') 90 p++; 91 for (q = p; *q != '\0'; q++) 92 if (! is_digit(*q)) 93 return 0; 94 if (q - p > 10 || 95 (q - p == 10 && memcmp(p, "2147483647", 10) > 0)) 96 return 0; 97 return 1; 98 } 99