1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 #endif /* not lint */ 37 #include <sys/cdefs.h> 38 /* 39 * String functions. 40 * 41 * equal(s1, s2) Return true if strings are equal. 42 * number(s) Convert a string of digits to an integer. 43 * is_number(s) Return true if s is a string of digits. 44 */ 45 46 #include <stdlib.h> 47 #include "shell.h" 48 #include "syntax.h" 49 #include "error.h" 50 #include "mystring.h" 51 52 53 char nullstr[1]; /* zero length string */ 54 55 /* 56 * equal - #defined in mystring.h 57 */ 58 59 60 /* 61 * Convert a string of digits to an integer, printing an error message on 62 * failure. 63 */ 64 65 int 66 number(const char *s) 67 { 68 if (! is_number(s)) 69 error("Illegal number: %s", s); 70 return atoi(s); 71 } 72 73 74 75 /* 76 * Check for a valid number. This should be elsewhere. 77 */ 78 79 int 80 is_number(const char *p) 81 { 82 const char *q; 83 84 if (*p == '\0') 85 return 0; 86 while (*p == '0') 87 p++; 88 for (q = p; *q != '\0'; q++) 89 if (! is_digit(*q)) 90 return 0; 91 if (q - p > 10 || 92 (q - p == 10 && memcmp(p, "2147483647", 10) > 0)) 93 return 0; 94 return 1; 95 } 96