1 /*- 2 * Copyright (c) 1991, 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 * Kenneth Almquist. 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 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)mystring.c 8.2 (Berkeley) 5/4/95"; 36 #endif 37 #endif /* not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 /* 42 * String functions. 43 * 44 * equal(s1, s2) Return true if strings are equal. 45 * scopy(from, to) Copy a string. 46 * number(s) Convert a string of digits to an integer. 47 * is_number(s) Return true if s is a string of digits. 48 */ 49 50 #include <stdlib.h> 51 #include "shell.h" 52 #include "syntax.h" 53 #include "error.h" 54 #include "mystring.h" 55 56 57 char nullstr[1]; /* zero length string */ 58 59 /* 60 * equal - #defined in mystring.h 61 */ 62 63 /* 64 * scopy - #defined in mystring.h 65 */ 66 67 68 /* 69 * prefix -- see if pfx is a prefix of string. 70 */ 71 72 int 73 prefix(const char *pfx, const char *string) 74 { 75 while (*pfx) { 76 if (*pfx++ != *string++) 77 return 0; 78 } 79 return 1; 80 } 81 82 83 /* 84 * Convert a string of digits to an integer, printing an error message on 85 * failure. 86 */ 87 88 int 89 number(const char *s) 90 { 91 if (! is_number(s)) 92 error("Illegal number: %s", s); 93 return atoi(s); 94 } 95 96 97 98 /* 99 * Check for a valid number. This should be elsewhere. 100 */ 101 102 int 103 is_number(const char *p) 104 { 105 do { 106 if (! is_digit(*p)) 107 return 0; 108 } while (*++p != '\0'); 109 return 1; 110 } 111