1 /* $OpenBSD: re.c,v 1.19 2018/06/19 12:36:18 martijn Exp $ */ 2 /* $NetBSD: re.c,v 1.14 1995/03/21 09:04:48 cgd Exp $ */ 3 4 /* re.c: This file contains the regular expression interface routines for 5 the ed line editor. */ 6 /*- 7 * Copyright (c) 1993 Andrew Moore, Talke Studio. 8 * All rights reserved. 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <regex.h> 33 #include <signal.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 38 #include "ed.h" 39 40 static char *extract_pattern(int); 41 static char *parse_char_class(char *); 42 43 extern int patlock; 44 45 46 /* get_compiled_pattern: return pointer to compiled pattern from command 47 buffer */ 48 regex_t * 49 get_compiled_pattern(void) 50 { 51 static regex_t *exp = NULL; 52 char errbuf[128] = ""; 53 54 char *exps; 55 char delimiter; 56 int n; 57 58 if ((delimiter = *ibufp) == ' ') { 59 seterrmsg("invalid pattern delimiter"); 60 return NULL; 61 } else if (delimiter == '\n' || *++ibufp == '\n' || *ibufp == delimiter) { 62 if (!exp) 63 seterrmsg("no previous pattern"); 64 return exp; 65 } else if ((exps = extract_pattern(delimiter)) == NULL) 66 return NULL; 67 /* buffer alloc'd && not reserved */ 68 if (exp && !patlock) 69 regfree(exp); 70 else if ((exp = malloc(sizeof(regex_t))) == NULL) { 71 perror(NULL); 72 seterrmsg("out of memory"); 73 return NULL; 74 } 75 patlock = 0; 76 if ((n = regcomp(exp, exps, 0)) != 0) { 77 regerror(n, exp, errbuf, sizeof errbuf); 78 seterrmsg(errbuf); 79 free(exp); 80 return exp = NULL; 81 } 82 return exp; 83 } 84 85 86 /* extract_pattern: copy a pattern string from the command buffer; return 87 pointer to the copy */ 88 static char * 89 extract_pattern(int delimiter) 90 { 91 static char *lhbuf = NULL; /* buffer */ 92 static int lhbufsz = 0; /* buffer size */ 93 94 char *nd; 95 int len; 96 97 for (nd = ibufp; *nd != delimiter && *nd != '\n'; nd++) 98 switch (*nd) { 99 default: 100 break; 101 case '[': 102 if ((nd = parse_char_class(++nd)) == NULL) { 103 seterrmsg("unbalanced brackets ([])"); 104 return NULL; 105 } 106 break; 107 case '\\': 108 if (*++nd == '\n') { 109 seterrmsg("trailing backslash (\\)"); 110 return NULL; 111 } 112 break; 113 } 114 len = nd - ibufp; 115 REALLOC(lhbuf, lhbufsz, len + 1, NULL); 116 memcpy(lhbuf, ibufp, len); 117 lhbuf[len] = '\0'; 118 ibufp = nd; 119 return (isbinary) ? NUL_TO_NEWLINE(lhbuf, len) : lhbuf; 120 } 121 122 123 /* parse_char_class: expand a POSIX character class */ 124 static char * 125 parse_char_class(char *s) 126 { 127 int c, d; 128 129 if (*s == '^') 130 s++; 131 if (*s == ']') 132 s++; 133 for (; *s != ']' && *s != '\n'; s++) 134 if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) 135 for (s++, c = *++s; *s != ']' || c != d; s++) 136 if ((c = *s) == '\n') 137 return NULL; 138 return (*s == ']') ? s : NULL; 139 } 140