Add vis and unvis

6 files changed, 594 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index 814f041..0408ecc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2006-03-19  Robert Millan  <rmh@aybabtu.com>
+
+	* src/vis.c: New file.
+	* src/unvis.c: Ditto.
+	* include/vis.h: Add vis/unvis declarations.
+	* Makefile (LIB_SRCS): Add vis.c/unvis.c.
+	* Versions: Add vis/unvis functions.
+
 2006-03-17  Robert Millan  <rmh@aybabtu.com>
 
 	* src/progname.c: New file.
diff --git a/Makefile b/Makefile
index e84f454..89276f3 100644
--- a/Makefile
+++ b/Makefile
@@ -5,12 +5,12 @@
 #
 
 LIB_SRCS := arc4random.c bsd_getopt.c err.c fgetln.c inet_net_pton.c \
-	    strlcat.c strlcpy.c md5c.c fmtcheck.c progname.c
+	    strlcat.c strlcpy.c md5c.c fmtcheck.c progname.c vis.c unvis.c
 LIB_SRCS := $(patsubst %,src/%,$(LIB_SRCS))
 
-LIB_INCLUDES := err.h getopt.h ip_icmp.h random.h queue.h md5.h string.h \
-		bsd.h cdefs.h stdlib.h
-LIB_INCLUDES := $(patsubst %,include/bsd/%,$(LIB_INCLUDES))
+LIB_INCLUDES := bsd/err.h bsd/getopt.h bsd/ip_icmp.h bsd/random.h bsd/queue.h bsd/md5.h bsd/string.h \
+		bsd/bsd.h bsd/cdefs.h bsd/stdlib.h vis.h
+LIB_INCLUDES := $(patsubst %,include/%,$(LIB_INCLUDES))
 
 LIB_MANS := arc4random.3 strlcpy.3 fgetln.3 fmtcheck.3
 LIB_MANS := $(patsubst %,man/%,$(LIB_MANS))
diff --git a/Versions b/Versions
index 77d3f29..0724ffb 100644
--- a/Versions
+++ b/Versions
@@ -10,6 +10,8 @@ LIBBSD_0.0 {
     getprogname; setprogname;
     strlcpy;
     strlcat;
+    vis; strvis; strvisx;
+    unvis; strunvis; strunvisx;
     MD5Init;
     MD5Update;
     MD5Pad;
diff --git a/include/vis.h b/include/vis.h
new file mode 100644
index 0000000..329481b
--- /dev/null
+++ b/include/vis.h
@@ -0,0 +1,90 @@
+/*-
+ * Copyright (c) 1990, 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.
+ *
+ *	@(#)vis.h	8.1 (Berkeley) 6/2/93
+ * $FreeBSD: src/include/vis.h,v 1.11 2003/10/30 10:40:49 phk Exp $
+ */
+
+#ifndef _VIS_H_
+#define	_VIS_H_
+
+#include <sys/types.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 */
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+char	*vis(char *, int, int, int);
+int	strvis(char *, const char *, int);
+int	strvisx(char *, const char *, size_t, int);
+int	strunvis(char *, const char *);
+int	strunvisx(char *, const char *, int);
+int	unvis(char *, int, int *, int);
+__END_DECLS
+
+#endif /* !_VIS_H_ */
diff --git a/src/unvis.c b/src/unvis.c
new file mode 100644
index 0000000..b567136
--- /dev/null
+++ b/src/unvis.c
@@ -0,0 +1,291 @@
+/*-
+ * 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	S_HEX2		7	/* hex digit 2 */
+
+#define	S_HTTP		0x080	/* %HEXHEX escape */
+
+#define	isoctal(c)	(((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
+#define	ishex(c)	((((u_char)(c)) >= '0' && ((u_char)(c)) <= '9') || (((u_char)(c)) >= 'a' && ((u_char)(c)) <= 'f'))
+
+/*
+ * unvis - decode characters previously encoded by vis
+ */
+int
+unvis(char *cp, int c, int *astate, int 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 & ~S_HTTP) {
+
+	case S_GROUND:
+		*cp = 0;
+		if (c == '\\') {
+			*astate = S_START;
+			return (0);
+		}
+		if (flag & VIS_HTTPSTYLE && c == '%') {
+			*astate = S_START | S_HTTP;
+			return (0);
+		}
+		*cp = c;
+		return (UNVIS_VALID);
+
+	case S_START:
+		if (*astate & S_HTTP) {
+		    if (ishex(tolower(c))) {
+			*cp = isdigit(c) ? (c - '0') : (tolower(c) - 'a');
+			*astate = S_HEX2;
+			return (0);
+		    }
+		}
+		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);
+
+	case S_HEX2:	/* second mandatory hex digit */
+		if (ishex(tolower(c))) {
+			*cp = (isdigit(c) ? (*cp << 4) + (c - '0') : (*cp << 4) + (tolower(c) - 'a' + 10));
+		}
+		*astate = S_GROUND;
+		return (UNVIS_VALID);
+
+	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(char *dst, const char *src)
+{
+	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);
+}
+
+int
+strunvisx(char *dst, const char *src, int flag)
+{
+	char c;
+	char *start = dst;
+	int state = 0;
+    
+	while ( (c = *src++) ) {
+	again:
+		switch (unvis(dst, c, &state, flag)) {
+		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);
+}
diff --git a/src/vis.c b/src/vis.c
new file mode 100644
index 0000000..bd3f6f9
--- /dev/null
+++ b/src/vis.c
@@ -0,0 +1,199 @@
+/*-
+ * 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 <limits.h>
+#include <ctype.h>
+#include <stdio.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)
+	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);
+}
+
+/*
+ * 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 NUL,
+ *	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)
+	char *dst;
+	const char *src;
+	int flag;
+{
+	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)
+	char *dst;
+	const char *src;
+	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);
+}