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 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)mystring.c 8.2 (Berkeley) 5/4/95"; 40 #endif 41 static const char rcsid[] = 42 "$FreeBSD$"; 43 #endif /* not lint */ 44 45 /* 46 * String functions. 47 * 48 * equal(s1, s2) Return true if strings are equal. 49 * scopy(from, to) Copy a string. 50 * scopyn(from, to, n) Like scopy, but checks for overflow. 51 * number(s) Convert a string of digits to an integer. 52 * is_number(s) Return true if s is a string of digits. 53 */ 54 55 #include <stdlib.h> 56 #include "shell.h" 57 #include "syntax.h" 58 #include "error.h" 59 #include "mystring.h" 60 61 62 char nullstr[1]; /* zero length string */ 63 64 /* 65 * equal - #defined in mystring.h 66 */ 67 68 /* 69 * scopy - #defined in mystring.h 70 */ 71 72 73 /* 74 * scopyn - copy a string from "from" to "to", truncating the string 75 * if necessary. "To" is always nul terminated, even if 76 * truncation is performed. "Size" is the size of "to". 77 */ 78 79 void 80 scopyn(from, to, size) 81 char const *from; 82 char *to; 83 int size; 84 { 85 86 while (--size > 0) { 87 if ((*to++ = *from++) == '\0') 88 return; 89 } 90 *to = '\0'; 91 } 92 93 94 /* 95 * prefix -- see if pfx is a prefix of string. 96 */ 97 98 int 99 prefix(pfx, string) 100 char const *pfx; 101 char const *string; 102 { 103 while (*pfx) { 104 if (*pfx++ != *string++) 105 return 0; 106 } 107 return 1; 108 } 109 110 111 /* 112 * Convert a string of digits to an integer, printing an error message on 113 * failure. 114 */ 115 116 int 117 number(s) 118 const char *s; 119 { 120 121 if (! is_number(s)) 122 error("Illegal number: %s", (char *)s); 123 return atoi(s); 124 } 125 126 127 128 /* 129 * Check for a valid number. This should be elsewhere. 130 */ 131 132 int 133 is_number(p) 134 const char *p; 135 { 136 do { 137 if (! is_digit(*p)) 138 return 0; 139 } while (*++p != '\0'); 140 return 1; 141 } 142