1 /* $NetBSD: unvis.c,v 1.19 2000/01/22 22:19:13 mycroft Exp $ */
2
3 /*-
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #if 1
33 #include <config.h>
34 #include "roken.h"
35 #ifndef _DIAGASSERT
36 #define _DIAGASSERT(X)
37 #endif
38 #else
39 #include <sys/cdefs.h>
40 #if defined(LIBC_SCCS) && !defined(lint)
41 #if 0
42 static char sccsid[] = "@(#)unvis.c 8.1 (Berkeley) 6/4/93";
43 #else
44 __RCSID("$NetBSD: unvis.c,v 1.19 2000/01/22 22:19:13 mycroft Exp $");
45 #endif
46 #endif /* LIBC_SCCS and not lint */
47
48 #define __LIBC12_SOURCE__
49
50 #include "namespace.h"
51 #endif
52 #include <sys/types.h>
53
54 #include <assert.h>
55 #include <ctype.h>
56 #include <stdio.h>
57 #include <vis.h>
58
59 #if 0
60 #ifdef __weak_alias
61 __weak_alias(strunvis,_strunvis)
62 __weak_alias(unvis,_unvis)
63 #endif
64
65 __warn_references(unvis,
66 "warning: reference to compatibility unvis(); include <vis.h> for correct reference")
67 #endif
68
69 /*
70 * decode driven by state machine
71 */
72 #define S_GROUND 0 /* haven't seen escape char */
73 #define S_START 1 /* start decoding special sequence */
74 #define S_META 2 /* metachar started (M) */
75 #define S_META1 3 /* metachar more, regular char (-) */
76 #define S_CTRL 4 /* control char started (^) */
77 #define S_OCTAL2 5 /* octal digit 2 */
78 #define S_OCTAL3 6 /* octal digit 3 */
79
80 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
81
82 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
83 rk_strunvis (char *, const char *);
84 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
85 rk_unvis (char *, int, int *, int);
86
87 /*
88 * unvis - decode characters previously encoded by vis
89 */
90
91 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_unvis(char * cp,int c,int * astate,int flag)92 rk_unvis(char *cp, int c, int *astate, int flag)
93 {
94
95 _DIAGASSERT(cp != NULL);
96 _DIAGASSERT(astate != NULL);
97
98 if (flag & UNVIS_END) {
99 if (*astate == S_OCTAL2 || *astate == S_OCTAL3) {
100 *astate = S_GROUND;
101 return (UNVIS_VALID);
102 }
103 return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD);
104 }
105
106 switch (*astate) {
107
108 case S_GROUND:
109 *cp = 0;
110 if (c == '\\') {
111 *astate = S_START;
112 return (0);
113 }
114 *cp = c;
115 return (UNVIS_VALID);
116
117 case S_START:
118 switch(c) {
119 case '\\':
120 *cp = c;
121 *astate = S_GROUND;
122 return (UNVIS_VALID);
123 case '0': case '1': case '2': case '3':
124 case '4': case '5': case '6': case '7':
125 *cp = (c - '0');
126 *astate = S_OCTAL2;
127 return (0);
128 case 'M':
129 *cp = (u_char)0200;
130 *astate = S_META;
131 return (0);
132 case '^':
133 *astate = S_CTRL;
134 return (0);
135 case 'n':
136 *cp = '\n';
137 *astate = S_GROUND;
138 return (UNVIS_VALID);
139 case 'r':
140 *cp = '\r';
141 *astate = S_GROUND;
142 return (UNVIS_VALID);
143 case 'b':
144 *cp = '\b';
145 *astate = S_GROUND;
146 return (UNVIS_VALID);
147 case 'a':
148 *cp = '\007';
149 *astate = S_GROUND;
150 return (UNVIS_VALID);
151 case 'v':
152 *cp = '\v';
153 *astate = S_GROUND;
154 return (UNVIS_VALID);
155 case 't':
156 *cp = '\t';
157 *astate = S_GROUND;
158 return (UNVIS_VALID);
159 case 'f':
160 *cp = '\f';
161 *astate = S_GROUND;
162 return (UNVIS_VALID);
163 case 's':
164 *cp = ' ';
165 *astate = S_GROUND;
166 return (UNVIS_VALID);
167 case 'E':
168 *cp = '\033';
169 *astate = S_GROUND;
170 return (UNVIS_VALID);
171 case '\n':
172 /*
173 * hidden newline
174 */
175 *astate = S_GROUND;
176 return (UNVIS_NOCHAR);
177 case '$':
178 /*
179 * hidden marker
180 */
181 *astate = S_GROUND;
182 return (UNVIS_NOCHAR);
183 }
184 *astate = S_GROUND;
185 return (UNVIS_SYNBAD);
186
187 case S_META:
188 if (c == '-')
189 *astate = S_META1;
190 else if (c == '^')
191 *astate = S_CTRL;
192 else {
193 *astate = S_GROUND;
194 return (UNVIS_SYNBAD);
195 }
196 return (0);
197
198 case S_META1:
199 *astate = S_GROUND;
200 *cp |= c;
201 return (UNVIS_VALID);
202
203 case S_CTRL:
204 if (c == '?')
205 *cp |= 0177;
206 else
207 *cp |= c & 037;
208 *astate = S_GROUND;
209 return (UNVIS_VALID);
210
211 case S_OCTAL2: /* second possible octal digit */
212 if (isoctal(c)) {
213 /*
214 * yes - and maybe a third
215 */
216 *cp = (*cp << 3) + (c - '0');
217 *astate = S_OCTAL3;
218 return (0);
219 }
220 /*
221 * no - done with current sequence, push back passed char
222 */
223 *astate = S_GROUND;
224 return (UNVIS_VALIDPUSH);
225
226 case S_OCTAL3: /* third possible octal digit */
227 *astate = S_GROUND;
228 if (isoctal(c)) {
229 *cp = (*cp << 3) + (c - '0');
230 return (UNVIS_VALID);
231 }
232 /*
233 * we were done, push back passed char
234 */
235 return (UNVIS_VALIDPUSH);
236
237 default:
238 /*
239 * decoder in unknown state - (probably uninitialized)
240 */
241 *astate = S_GROUND;
242 return (UNVIS_SYNBAD);
243 }
244 }
245
246 /*
247 * strunvis - decode src into dst
248 *
249 * Number of chars decoded into dst is returned, -1 on error.
250 * Dst is null terminated.
251 */
252
253 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_strunvis(char * dst,const char * src)254 rk_strunvis(char *dst, const char *src)
255 {
256 char c;
257 char *start = dst;
258 int state = 0;
259
260 _DIAGASSERT(src != NULL);
261 _DIAGASSERT(dst != NULL);
262
263 while ((c = *src++) != '\0') {
264 again:
265 switch (rk_unvis(dst, (unsigned char)c, &state, 0)) {
266 case UNVIS_VALID:
267 dst++;
268 break;
269 case UNVIS_VALIDPUSH:
270 dst++;
271 goto again;
272 case 0:
273 case UNVIS_NOCHAR:
274 break;
275 default:
276 return (-1);
277 }
278 }
279 if (unvis(dst, (unsigned char)c, &state, UNVIS_END) == UNVIS_VALID)
280 dst++;
281 *dst = '\0';
282 return (dst - start);
283 }
284