freebsd-skq/lib/libc/gen/vis.c
1996-03-25 14:32:30 +00:00

188 lines
4.5 KiB
C

/*-
* 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)vis.c 8.1 (Berkeley) 7/19/93";
#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;
{
c = (unsigned char)c;
if (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;
{
int c;
char *start;
for (start = dst; len > 1; len--) {
c = *src;
dst = vis(dst, c, flag, *++src);
}
if (len)
dst = vis(dst, *src, flag, '\0');
*dst = '\0';
return (dst - start);
}