1 /* $NetBSD: re.c,v 1.21 2014/03/23 05:06:42 dholland 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 1.21 2014/03/23 05:06:42 dholland Exp $");
37 #endif
38 #endif /* not lint */
39
40 #include <stdarg.h>
41 #include "ed.h"
42
43
44 char errmsg[MAXPATHLEN + 40] = "";
45
46 void
seterrmsg(const char * fmt,...)47 seterrmsg(const char *fmt, ...)
48 {
49 va_list ap;
50
51 va_start(ap, fmt);
52 vsnprintf(errmsg, sizeof(errmsg), fmt, ap);
53 va_end(ap);
54 }
55
56 /* get_compiled_pattern: return pointer to compiled pattern from command
57 buffer */
58 pattern_t *
get_compiled_pattern(void)59 get_compiled_pattern(void)
60 {
61 static pattern_t *expr = NULL;
62
63 char *exps;
64 char delimiter;
65 int n;
66
67 if ((delimiter = *ibufp) == ' ') {
68 seterrmsg("invalid pattern delimiter");
69 return NULL;
70 } else if (delimiter == '\n' || *++ibufp == '\n' || *ibufp == delimiter) {
71 if (!expr) seterrmsg("no previous pattern");
72 return expr;
73 } else if ((exps = extract_pattern(delimiter)) == NULL)
74 return NULL;
75 /* buffer alloc'd && not reserved */
76 if (expr && !patlock)
77 regfree(expr);
78 else if ((expr = (pattern_t *) malloc(sizeof(pattern_t))) == NULL) {
79 fprintf(stderr, "%s\n", strerror(errno));
80 seterrmsg("out of memory");
81 return NULL;
82 }
83 patlock = 0;
84 if ((n = regcomp(expr, exps, ere)) != 0) {
85 regerror(n, expr, errmsg, sizeof errmsg);
86 free(expr);
87 return expr = NULL;
88 }
89 return expr;
90 }
91
92
93 /* extract_pattern: copy a pattern string from the command buffer; return
94 pointer to the copy */
95 char *
extract_pattern(int delimiter)96 extract_pattern(int delimiter)
97 {
98 static char *lhbuf = NULL; /* buffer */
99 static int lhbufsz = 0; /* buffer size */
100
101 char *nd;
102 int len;
103
104 for (nd = ibufp; *nd != delimiter && *nd != '\n'; nd++)
105 switch (*nd) {
106 default:
107 break;
108 case '[':
109 if ((nd = parse_char_class(nd + 1)) == NULL) {
110 seterrmsg("unbalanced brackets ([])");
111 return NULL;
112 }
113 break;
114 case '\\':
115 if (*++nd == '\n') {
116 seterrmsg("trailing backslash (\\)");
117 return NULL;
118 }
119 break;
120 }
121 len = nd - ibufp;
122 REALLOC(lhbuf, lhbufsz, len + 1, NULL);
123 memcpy(lhbuf, ibufp, len);
124 lhbuf[len] = '\0';
125 ibufp = nd;
126 return (isbinary) ? NUL_TO_NEWLINE(lhbuf, len) : lhbuf;
127 }
128
129
130 /* parse_char_class: expand a POSIX character class */
131 char *
parse_char_class(char * s)132 parse_char_class(char *s)
133 {
134 int c, d;
135
136 if (*s == '^')
137 s++;
138 if (*s == ']')
139 s++;
140 for (; *s != ']' && *s != '\n'; s++)
141 if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '='))
142 for (s++, c = *++s; *s != ']' || c != d; s++)
143 if ((c = *s) == '\n')
144 return NULL;
145 return (*s == ']') ? s : NULL;
146 }
147