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/*-
* 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.
* 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.
*
* Defived from FreeBSD head/lib/libc/gen/vis.c 165903, head/include/vis.h
* 203964.
*/
#include <sys/types.h>
#include <limits.h>
#include <ctype.h>
#include <stdio.h>
/*
* to select alternate encoding format
*/
#define VIS_OCTAL 0x01 /* use octal \ddd format */
#define VIS_CSTYLE 0x02 /* use \[nrft0..] where appropriate */
/*
* to alter set of characters encoded (default is to encode all
* non-graphic except space, tab, and newline).
*/
#define VIS_SP 0x04 /* also encode space */
#define VIS_TAB 0x08 /* also encode tab */
#define VIS_NL 0x10 /* also encode newline */
#define VIS_WHITE (VIS_SP | VIS_TAB | VIS_NL)
#define VIS_SAFE 0x20 /* only encode "unsafe" characters */
/*
* other
*/
#define VIS_NOSLASH 0x40 /* inhibit printing '\' */
#define VIS_HTTPSTYLE 0x80 /* http-style escape % HEX HEX */
#define VIS_GLOB 0x100 /* encode glob(3) magics */
/*
* unvis return codes
*/
#define UNVIS_VALID 1 /* character valid */
#define UNVIS_VALIDPUSH 2 /* character valid, push back passed char */
#define UNVIS_NOCHAR 3 /* valid sequence, no character produced */
#define UNVIS_SYNBAD -1 /* unrecognized escape sequence */
#define UNVIS_ERROR -2 /* decoder in unknown state (unrecoverable) */
/*
* unvis flags
*/
#define UNVIS_END 1 /* no more characters */
#define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
/*
* vis - visually encode characters
*/
char *
vis(dst, c, flag, nextc)
char *dst;
int c, nextc;
int flag;
{
c = (unsigned char)c;
if (flag & VIS_HTTPSTYLE) {
/* Described in RFC 1808 */
if (!(isalnum(c) /* alpha-numeric */
/* safe */
|| c == '$' || c == '-' || c == '_' || c == '.' || c == '+'
/* extra */
|| c == '!' || c == '*' || c == '\'' || c == '('
|| c == ')' || c == ',')) {
*dst++ = '%';
snprintf(dst, 4, (c < 16 ? "0%X" : "%X"), c);
dst += 2;
goto done;
}
}
if ((flag & VIS_GLOB) &&
(c == '*' || c == '?' || c == '[' || c == '#'))
;
else 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;
case '\a':
*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) == ' ') || isgraph(c) || (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);
}
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