[apple/libc.git] / gen / unvis.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */


#include <sys/types.h>
#include <ctype.h>
#include <vis.h>

/*
 * decode driven by state machine
 */
#define	S_GROUND	0	/* haven't seen escape char */
#define	S_START		1	/* start decoding special sequence */
#define	S_META		2	/* metachar started (M) */
#define	S_META1		3	/* metachar more, regular char (-) */
#define	S_CTRL		4	/* control char started (^) */
#define	S_OCTAL2	5	/* octal digit 2 */
#define	S_OCTAL3	6	/* octal digit 3 */

#define	isoctal(c)	(((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')

/*
 * unvis - decode characters previously encoded by vis
 */
int
unvis(cp, c, astate, flag)
	char *cp;
	int c, *astate, flag;
{

	if (flag & UNVIS_END) {
		if (*astate == S_OCTAL2 || *astate == S_OCTAL3) {
			*astate = S_GROUND;
			return (UNVIS_VALID);
		} 
		return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD);
	}

	switch (*astate) {

	case S_GROUND:
		*cp = 0;
		if (c == '\\') {
			*astate = S_START;
			return (0);
		} 
		*cp = c;
		return (UNVIS_VALID);

	case S_START:
		switch(c) {
		case '\\':
			*cp = c;
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case '0': case '1': case '2': case '3':
		case '4': case '5': case '6': case '7':
			*cp = (c - '0');
			*astate = S_OCTAL2;
			return (0);
		case 'M':
			*cp = 0200;
			*astate = S_META;
			return (0);
		case '^':
			*astate = S_CTRL;
			return (0);
		case 'n':
			*cp = '\n';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 'r':
			*cp = '\r';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 'b':
			*cp = '\b';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 'a':
			*cp = '\007';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 'v':
			*cp = '\v';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 't':
			*cp = '\t';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 'f':
			*cp = '\f';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 's':
			*cp = ' ';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case 'E':
			*cp = '\033';
			*astate = S_GROUND;
			return (UNVIS_VALID);
		case '\n':
			/*
			 * hidden newline
			 */
			*astate = S_GROUND;
			return (UNVIS_NOCHAR);
		case '$':
			/*
			 * hidden marker
			 */
			*astate = S_GROUND;
			return (UNVIS_NOCHAR);
		}
		*astate = S_GROUND;
		return (UNVIS_SYNBAD);
		 
	case S_META:
		if (c == '-')
			*astate = S_META1;
		else if (c == '^')
			*astate = S_CTRL;
		else {
			*astate = S_GROUND;
			return (UNVIS_SYNBAD);
		}
		return (0);
		 
	case S_META1:
		*astate = S_GROUND;
		*cp |= c;
		return (UNVIS_VALID);
		 
	case S_CTRL:
		if (c == '?')
			*cp |= 0177;
		else
			*cp |= c & 037;
		*astate = S_GROUND;
		return (UNVIS_VALID);

	case S_OCTAL2:	/* second possible octal digit */
		if (isoctal(c)) {
			/* 
			 * yes - and maybe a third 
			 */
			*cp = (*cp << 3) + (c - '0');
			*astate = S_OCTAL3;	
			return (0);
		} 
		/* 
		 * no - done with current sequence, push back passed char 
		 */
		*astate = S_GROUND;
		return (UNVIS_VALIDPUSH);

	case S_OCTAL3:	/* third possible octal digit */
		*astate = S_GROUND;
		if (isoctal(c)) {
			*cp = (*cp << 3) + (c - '0');
			return (UNVIS_VALID);
		}
		/*
		 * we were done, push back passed char
		 */
		return (UNVIS_VALIDPUSH);
			
	default:	
		/* 
		 * decoder in unknown state - (probably uninitialized) 
		 */
		*astate = S_GROUND;
		return (UNVIS_SYNBAD);
	}
}

/*
 * strunvis - decode src into dst 
 *
 *	Number of chars decoded into dst is returned, -1 on error.
 *	Dst is null terminated.
 */

int
strunvis(dst, src)
	register char *dst;
	register const char *src;
{
	register char c;
	char *start = dst;
	int state = 0;

	while (c = *src++) {
	again:
		switch (unvis(dst, c, &state, 0)) {
		case UNVIS_VALID:
			dst++;
			break;
		case UNVIS_VALIDPUSH:
			dst++;
			goto again;
		case 0:
		case UNVIS_NOCHAR:
			break;
		default:
			return (-1);
		}
	}
	if (unvis(dst, c, &state, UNVIS_END) == UNVIS_VALID)
		dst++;
	*dst = '\0';
	return (dst - start);
}
Commit	Line	Data
e9ce8d39 A	1	/*
	2	* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
734aad71	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
e9ce8d39	7	*
734aad71 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
e9ce8d39 A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
e9ce8d39 A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
734aad71 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
e9ce8d39 A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/*
	26	* Copyright (c) 1989, 1993
	27	* The Regents of the University of California. All rights reserved.
	28	*
	29	* Redistribution and use in source and binary forms, with or without
	30	* modification, are permitted provided that the following conditions
	31	* are met:
	32	* 1. Redistributions of source code must retain the above copyright
	33	* notice, this list of conditions and the following disclaimer.
	34	* 2. Redistributions in binary form must reproduce the above copyright
	35	* notice, this list of conditions and the following disclaimer in the
	36	* documentation and/or other materials provided with the distribution.
	37	* 3. All advertising materials mentioning features or use of this software
	38	* must display the following acknowledgement:
	39	* This product includes software developed by the University of
	40	* California, Berkeley and its contributors.
	41	* 4. Neither the name of the University nor the names of its contributors
	42	* may be used to endorse or promote products derived from this software
	43	* without specific prior written permission.
	44	*
	45	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	46	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	47	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	48	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	49	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	50	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	51	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	52	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	53	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	54	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	55	* SUCH DAMAGE.
	56	*/
	57
	58
	59	#include <sys/types.h>
	60	#include <ctype.h>
	61	#include <vis.h>
	62
	63	/*
	64	* decode driven by state machine
	65	*/
	66	#define S_GROUND 0 /* haven't seen escape char */
	67	#define S_START 1 /* start decoding special sequence */
	68	#define S_META 2 /* metachar started (M) */
	69	#define S_META1 3 /* metachar more, regular char (-) */
	70	#define S_CTRL 4 /* control char started (^) */
	71	#define S_OCTAL2 5 /* octal digit 2 */
	72	#define S_OCTAL3 6 /* octal digit 3 */
	73
	74	#define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
	75
	76	/*
	77	* unvis - decode characters previously encoded by vis
	78	*/
	79	int
	80	unvis(cp, c, astate, flag)
	81	char *cp;
	82	int c, *astate, flag;
	83	{
	84
	85	if (flag & UNVIS_END) {
86	if (astate == S_OCTAL2 \|\| astate == S_OCTAL3) {
87	*astate = S_GROUND;
88	return (UNVIS_VALID);
89	}
90	return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD);
91	}
92
93	switch (*astate) {
94
95	case S_GROUND:
96	*cp = 0;
97	if (c == '\\') {
98	*astate = S_START;
99	return (0);
100	}
101	*cp = c;
102	return (UNVIS_VALID);
103
104	case S_START:
105	switch(c) {
106	case '\\':
107	*cp = c;
108	*astate = S_GROUND;
109	return (UNVIS_VALID);
110	case '0': case '1': case '2': case '3':
111	case '4': case '5': case '6': case '7':
112	*cp = (c - '0');
113	*astate = S_OCTAL2;
114	return (0);
115	case 'M':
116	*cp = 0200;
117	*astate = S_META;
118	return (0);
119	case '^':
120	*astate = S_CTRL;
121	return (0);
122	case 'n':
123	*cp = '\n';
124	*astate = S_GROUND;
125	return (UNVIS_VALID);
126	case 'r':
127	*cp = '\r';
128	*astate = S_GROUND;
129	return (UNVIS_VALID);
130	case 'b':
131	*cp = '\b';
132	*astate = S_GROUND;
133	return (UNVIS_VALID);
134	case 'a':
135	*cp = '\007';
136	*astate = S_GROUND;
137	return (UNVIS_VALID);
138	case 'v':
139	*cp = '\v';
140	*astate = S_GROUND;
141	return (UNVIS_VALID);
142	case 't':
143	*cp = '\t';
144	*astate = S_GROUND;
145	return (UNVIS_VALID);
146	case 'f':
147	*cp = '\f';
148	*astate = S_GROUND;
149	return (UNVIS_VALID);
150	case 's':
151	*cp = ' ';
152	*astate = S_GROUND;
153	return (UNVIS_VALID);
154	case 'E':
155	*cp = '\033';
156	*astate = S_GROUND;
157	return (UNVIS_VALID);
158	case '\n':
159	/*
160	* hidden newline
161	*/
162	*astate = S_GROUND;
163	return (UNVIS_NOCHAR);
164	case '$':
165	/*
166	* hidden marker
167	*/
168	*astate = S_GROUND;
169	return (UNVIS_NOCHAR);
170	}
171	*astate = S_GROUND;
172	return (UNVIS_SYNBAD);
173
174	case S_META:
175	if (c == '-')
176	*astate = S_META1;
177	else if (c == '^')
178	*astate = S_CTRL;
179	else {
180	*astate = S_GROUND;
181	return (UNVIS_SYNBAD);
182	}
183	return (0);
184
185	case S_META1:
186	*astate = S_GROUND;
187	*cp \|= c;
188	return (UNVIS_VALID);
189
190	case S_CTRL:
191	if (c == '?')
192	*cp \|= 0177;
193	else
194	*cp \|= c & 037;
195	*astate = S_GROUND;
196	return (UNVIS_VALID);
197
198	case S_OCTAL2: /* second possible octal digit */
199	if (isoctal(c)) {
200	/*
201	* yes - and maybe a third
202	*/
203	cp = (cp << 3) + (c - '0');
204	*astate = S_OCTAL3;
205	return (0);
206	}
207	/*
208	* no - done with current sequence, push back passed char
209	*/
210	*astate = S_GROUND;
211	return (UNVIS_VALIDPUSH);
212
213	case S_OCTAL3: /* third possible octal digit */
214	*astate = S_GROUND;
215	if (isoctal(c)) {
216	cp = (cp << 3) + (c - '0');
217	return (UNVIS_VALID);
218	}
219	/*
220	* we were done, push back passed char
221	*/
222	return (UNVIS_VALIDPUSH);
223
224	default:
225	/*
226	* decoder in unknown state - (probably uninitialized)
227	*/
228	*astate = S_GROUND;
229	return (UNVIS_SYNBAD);
230	}
231	}
232
233	/*
234	* strunvis - decode src into dst
235	*
236	* Number of chars decoded into dst is returned, -1 on error.
237	* Dst is null terminated.
238	*/
239
240	int
241	strunvis(dst, src)
242	register char *dst;
243	register const char *src;
244	{
245	register char c;
246	char *start = dst;
247	int state = 0;
248
249	while (c = *src++) {
250	again:
251	switch (unvis(dst, c, &state, 0)) {
252	case UNVIS_VALID:
253	dst++;
254	break;
255	case UNVIS_VALIDPUSH:
256	dst++;
257	goto again;
258	case 0:
259	case UNVIS_NOCHAR:
260	break;
261	default:
262	return (-1);
263	}
264	}
265	if (unvis(dst, c, &state, UNVIS_END) == UNVIS_VALID)
266	dst++;
267	*dst = '\0';
268	return (dst - start);
269	}