[unix-history] / lib / libc / gen / vis.c

/*-
 * Copyright (c) 1989 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.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)vis.c	5.6 (Berkeley) 2/5/92";
#endif /* LIBC_SCCS and not lint */

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

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

/*
 * vis - visually encode characters
 */
char *
vis(dst, c, flag, nextc)
	register char *dst;
	int c, nextc;
	register int flag;
{
	if ((u_int)c <= UCHAR_MAX && isgraph(c) ||
	   ((flag & VIS_SP) == 0 && c == ' ') ||
	   ((flag & VIS_TAB) == 0 && c == '\t') ||
	   ((flag & VIS_NL) == 0 && c == '\n') ||
	   ((flag & VIS_SAFE) && (c == '\b' || c == '\007' || c == '\r'))) {
		*dst++ = c;
		if (c == '\\' && (flag & VIS_NOSLASH) == 0)
			*dst++ = '\\';
		*dst = '\0';
		return (dst);
	}

	if (flag & VIS_CSTYLE) {
		switch(c) {
		case '\n':
			*dst++ = '\\';
			*dst++ = 'n';
			goto done;
		case '\r':
			*dst++ = '\\';
			*dst++ = 'r';
			goto done;
		case '\b':
			*dst++ = '\\';
			*dst++ = 'b';
			goto done;
#if __STDC__
		case '\a':
#else
		case '\007':
#endif
			*dst++ = '\\';
			*dst++ = 'a';
			goto done;
		case '\v':
			*dst++ = '\\';
			*dst++ = 'v';
			goto done;
		case '\t':
			*dst++ = '\\';
			*dst++ = 't';
			goto done;
		case '\f':
			*dst++ = '\\';
			*dst++ = 'f';
			goto done;
		case ' ':
			*dst++ = '\\';
			*dst++ = 's';
			goto done;
		case '\0':
			*dst++ = '\\';
			*dst++ = '0';
			if (isoctal(nextc)) {
				*dst++ = '0';
				*dst++ = '0';
			}
			goto done;
		}
	}
	if (((c & 0177) == ' ') || (flag & VIS_OCTAL)) {	
		*dst++ = '\\';
		*dst++ = ((u_char)c >> 6 & 07) + '0';
		*dst++ = ((u_char)c >> 3 & 07) + '0';
		*dst++ = ((u_char)c & 07) + '0';
		goto done;
	}
	if ((flag & VIS_NOSLASH) == 0)
		*dst++ = '\\';
	if (c & 0200) {
		c &= 0177;
		*dst++ = 'M';
	}
	if (iscntrl(c)) {
		*dst++ = '^';
		if (c == 0177)
			*dst++ = '?';
		else
			*dst++ = c + '@';
	} else {
		*dst++ = '-';
		*dst++ = c;
	}
done:
	*dst = '\0';
	return (dst);
}

/*
 * strvis, strvisx - visually encode characters from src into dst
 *	
 *	Dst must be 4 times the size of src to account for possible
 *	expansion.  The length of dst, not including the trailing NULL,
 *	is returned. 
 *
 *	Strvisx encodes exactly len bytes from src into dst.
 *	This is useful for encoding a block of data.
 */
int
strvis(dst, src, flag)
	register char *dst;
	register const char *src;
	int flag;
{
	register char c;
	char *start;

	for (start = dst; c = *src;)
		dst = vis(dst, c, flag, *++src);
	*dst = '\0';
	return (dst - start);
}

int
strvisx(dst, src, len, flag)
	register char *dst;
	register const char *src;
	register size_t len;
	int flag;
{
	char *start = dst;

	while (len > 1) {
		dst = vis(dst, *src, flag, *(src+1));
		len--;
	}
	if (len)
		dst = vis(dst, *src, flag, '\0');

	return (dst - start);
}
Commit	Line	Data
15637ed4 RG	1	/*-
	2	* Copyright (c) 1989 The Regents of the University of California.
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*/
	33
	34	#if defined(LIBC_SCCS) && !defined(lint)
78ed81a3	35	static char sccsid[] = "@(#)vis.c 5.6 (Berkeley) 2/5/92";
15637ed4 RG	36	#endif /* LIBC_SCCS and not lint */
	37
	38	#include <sys/types.h>
78ed81a3	39	#include <limits.h>
15637ed4 RG	40	#include <ctype.h>
	41	#include <vis.h>
	42
	43	#define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
	44
	45	/*
	46	* vis - visually encode characters
	47	*/
	48	char *
15637ed4	49	vis(dst, c, flag, nextc)
78ed81a3	50	register char *dst;
78ed81a3	51	int c, nextc;
15637ed4	52	register int flag;
15637ed4	53	{
78ed81a3	54	if ((u_int)c <= UCHAR_MAX && isgraph(c) \|\|
15637ed4 RG	55	((flag & VIS_SP) == 0 && c == ' ') \|\|
	56	((flag & VIS_TAB) == 0 && c == '\t') \|\|
	57	((flag & VIS_NL) == 0 && c == '\n') \|\|
	58	((flag & VIS_SAFE) && (c == '\b' \|\| c == '\007' \|\| c == '\r'))) {
	59	*dst++ = c;
	60	if (c == '\\' && (flag & VIS_NOSLASH) == 0)
	61	*dst++ = '\\';
	62	*dst = '\0';
	63	return (dst);
	64	}
	65
	66	if (flag & VIS_CSTYLE) {
	67	switch(c) {
	68	case '\n':
	69	*dst++ = '\\';
	70	*dst++ = 'n';
	71	goto done;
	72	case '\r':
	73	*dst++ = '\\';
	74	*dst++ = 'r';
	75	goto done;
	76	case '\b':
	77	*dst++ = '\\';
	78	*dst++ = 'b';
	79	goto done;
	80	#if __STDC__
	81	case '\a':
	82	#else
	83	case '\007':
	84	#endif
	85	*dst++ = '\\';
	86	*dst++ = 'a';
	87	goto done;
	88	case '\v':
	89	*dst++ = '\\';
	90	*dst++ = 'v';
	91	goto done;
	92	case '\t':
	93	*dst++ = '\\';
	94	*dst++ = 't';
	95	goto done;
	96	case '\f':
	97	*dst++ = '\\';
	98	*dst++ = 'f';
	99	goto done;
	100	case ' ':
	101	*dst++ = '\\';
	102	*dst++ = 's';
	103	goto done;
	104	case '\0':
	105	*dst++ = '\\';
	106	*dst++ = '0';
	107	if (isoctal(nextc)) {
	108	*dst++ = '0';
	109	*dst++ = '0';
	110	}
	111	goto done;
	112	}
	113	}
	114	if (((c & 0177) == ' ') \|\| (flag & VIS_OCTAL)) {
	115	*dst++ = '\\';
	116	*dst++ = ((u_char)c >> 6 & 07) + '0';
	117	*dst++ = ((u_char)c >> 3 & 07) + '0';
	118	*dst++ = ((u_char)c & 07) + '0';
119	goto done;
120	}
121	if ((flag & VIS_NOSLASH) == 0)
122	*dst++ = '\\';
123	if (c & 0200) {
124	c &= 0177;
125	*dst++ = 'M';
126	}
127	if (iscntrl(c)) {
128	*dst++ = '^';
129	if (c == 0177)
130	*dst++ = '?';
131	else
132	*dst++ = c + '@';
133	} else {
134	*dst++ = '-';
135	*dst++ = c;
136	}
137	done:
138	*dst = '\0';
139	return (dst);
140	}
141
142	/*
143	* strvis, strvisx - visually encode characters from src into dst
144	*
145	* Dst must be 4 times the size of src to account for possible
146	* expansion. The length of dst, not including the trailing NULL,
147	* is returned.
148	*
149	* Strvisx encodes exactly len bytes from src into dst.
150	* This is useful for encoding a block of data.
151	*/
152	int
153	strvis(dst, src, flag)
154	register char *dst;
155	register const char *src;
156	int flag;
157	{
158	register char c;
78ed81a3	159	char *start;
15637ed4	160
78ed81a3	161	for (start = dst; c = *src;)
	162	dst = vis(dst, c, flag, *++src);
	163	*dst = '\0';
15637ed4 RG	164	return (dst - start);
	165	}
	166
	167	int
	168	strvisx(dst, src, len, flag)
	169	register char *dst;
	170	register const char *src;
	171	register size_t len;
	172	int flag;
	173	{
	174	char *start = dst;
	175
	176	while (len > 1) {
	177	dst = vis(dst, src, flag, (src+1));
	178	len--;
	179	}
	180	if (len)
	181	dst = vis(dst, *src, flag, '\0');
	182
	183	return (dst - start);
	184	}