1 /* $NetBSD: re.c,v 1.18 2002/12/06 01:39:10 thorpej Exp $ */ 2 3 /* re.c: This file contains the regular expression interface routines for 4 the ed line editor. */ 5 /*- 6 * Copyright (c) 1993 Andrew Moore, Talke Studio. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 #ifndef lint 33 #if 0 34 static char *rcsid = "@(#)re.c,v 1.6 1994/02/01 00:34:43 alm Exp"; 35 #else 36 __RCSID("$NetBSD: re.c,v 1.18 2002/12/06 01:39:10 thorpej Exp $"); 37 #endif 38 #endif /* not lint */ 39 40 #include "ed.h" 41 42 43 char errmsg[MAXPATHLEN + 40] = ""; 44 45 /* get_compiled_pattern: return pointer to compiled pattern from command 46 buffer */ 47 pattern_t * 48 get_compiled_pattern() 49 { 50 static pattern_t *expr = NULL; 51 52 char *exps; 53 char delimiter; 54 int n; 55 56 if ((delimiter = *ibufp) == ' ') { 57 sprintf(errmsg, "invalid pattern delimiter"); 58 return NULL; 59 } else if (delimiter == '\n' || *++ibufp == '\n' || *ibufp == delimiter) { 60 if (!expr) sprintf(errmsg, "no previous pattern"); 61 return expr; 62 } else if ((exps = extract_pattern(delimiter)) == NULL) 63 return NULL; 64 /* buffer alloc'd && not reserved */ 65 if (expr && !patlock) 66 regfree(expr); 67 else if ((expr = (pattern_t *) malloc(sizeof(pattern_t))) == NULL) { 68 fprintf(stderr, "%s\n", strerror(errno)); 69 sprintf(errmsg, "out of memory"); 70 return NULL; 71 } 72 patlock = 0; 73 if ((n = regcomp(expr, exps, ere)) != 0) { 74 regerror(n, expr, errmsg, sizeof errmsg); 75 free(expr); 76 return expr = NULL; 77 } 78 return expr; 79 } 80 81 82 /* extract_pattern: copy a pattern string from the command buffer; return 83 pointer to the copy */ 84 char * 85 extract_pattern(delimiter) 86 int delimiter; 87 { 88 static char *lhbuf = NULL; /* buffer */ 89 static int lhbufsz = 0; /* buffer size */ 90 91 char *nd; 92 int len; 93 94 for (nd = ibufp; *nd != delimiter && *nd != '\n'; nd++) 95 switch (*nd) { 96 default: 97 break; 98 case '[': 99 if ((nd = parse_char_class(++nd)) == NULL) { 100 sprintf(errmsg, "unbalanced brackets ([])"); 101 return NULL; 102 } 103 break; 104 case '\\': 105 if (*++nd == '\n') { 106 sprintf(errmsg, "trailing backslash (\\)"); 107 return NULL; 108 } 109 break; 110 } 111 len = nd - ibufp; 112 REALLOC(lhbuf, lhbufsz, len + 1, NULL); 113 memcpy(lhbuf, ibufp, len); 114 lhbuf[len] = '\0'; 115 ibufp = nd; 116 return (isbinary) ? NUL_TO_NEWLINE(lhbuf, len) : lhbuf; 117 } 118 119 120 /* parse_char_class: expand a POSIX character class */ 121 char * 122 parse_char_class(s) 123 char *s; 124 { 125 int c, d; 126 127 if (*s == '^') 128 s++; 129 if (*s == ']') 130 s++; 131 for (; *s != ']' && *s != '\n'; s++) 132 if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) 133 for (s++, c = *++s; *s != ']' || c != d; s++) 134 if ((c = *s) == '\n') 135 return NULL; 136 return (*s == ']') ? s : NULL; 137 } 138