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 1.14 2009/12/27 18:04:05 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 * scopyn(from, to, n) Like scopy, but checks for overflow. 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 * scopyn - copy a string from "from" to "to", truncating the string 70 * if necessary. "To" is always nul terminated, even if 71 * truncation is performed. "Size" is the size of "to". 72 */ 73 74 void 75 scopyn(const char *from, char *to, int size) 76 { 77 78 while (--size > 0) { 79 if ((*to++ = *from++) == '\0') 80 return; 81 } 82 *to = '\0'; 83 } 84 85 86 /* 87 * prefix -- see if pfx is a prefix of string. 88 */ 89 90 int 91 prefix(const char *pfx, const char *string) 92 { 93 while (*pfx) { 94 if (*pfx++ != *string++) 95 return 0; 96 } 97 return 1; 98 } 99 100 101 /* 102 * Convert a string of digits to an integer, printing an error message on 103 * failure. 104 */ 105 106 int 107 number(const char *s) 108 { 109 if (! is_number(s)) 110 error("Illegal number: %s", s); 111 return atoi(s); 112 } 113 114 115 116 /* 117 * Check for a valid number. This should be elsewhere. 118 */ 119 120 int 121 is_number(const char *p) 122 { 123 do { 124 if (! is_digit(*p)) 125 return 0; 126 } while (*++p != '\0'); 127 return 1; 128 } 129