Add vis and unvis
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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);
+}