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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)mystring.c 8.2 (Berkeley) 5/4/95 37 * $FreeBSD: src/bin/sh/mystring.c,v 1.15 2012/01/01 22:15:38 jilles Exp $ 38 */ 39 40 /* 41 * String functions. 42 * 43 * equal(s1, s2) Return true if strings are equal. 44 * scopy(from, to) Copy a string. 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 * scopy - #defined in mystring.h 64 */ 65 66 67 /* 68 * prefix -- see if pfx is a prefix of string. 69 */ 70 71 int 72 prefix(const char *pfx, const char *string) 73 { 74 while (*pfx) { 75 if (*pfx++ != *string++) 76 return 0; 77 } 78 return 1; 79 } 80 81 82 /* 83 * Convert a string of digits to an integer, printing an error message on 84 * failure. 85 */ 86 87 int 88 number(const char *s) 89 { 90 if (! is_number(s)) 91 error("Illegal number: %s", s); 92 return atoi(s); 93 } 94 95 96 97 /* 98 * Check for a valid number. This should be elsewhere. 99 */ 100 101 int 102 is_number(const char *p) 103 { 104 do { 105 if (! is_digit(*p)) 106 return 0; 107 } while (*++p != '\0'); 108 return 1; 109 } 110