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(const char *from, char *to, int size) 81 { 82 83 while (--size > 0) { 84 if ((*to++ = *from++) == '\0') 85 return; 86 } 87 *to = '\0'; 88 } 89 90 91 /* 92 * prefix -- see if pfx is a prefix of string. 93 */ 94 95 int 96 prefix(const char *pfx, const char *string) 97 { 98 while (*pfx) { 99 if (*pfx++ != *string++) 100 return 0; 101 } 102 return 1; 103 } 104 105 106 /* 107 * Convert a string of digits to an integer, printing an error message on 108 * failure. 109 */ 110 111 int 112 number(const char *s) 113 { 114 if (! is_number(s)) 115 error("Illegal number: %s", (char *)s); 116 return atoi(s); 117 } 118 119 120 121 /* 122 * Check for a valid number. This should be elsewhere. 123 */ 124 125 int 126 is_number(const char *p) 127 { 128 do { 129 if (! is_digit(*p)) 130 return 0; 131 } while (*++p != '\0'); 132 return 1; 133 } 134