freebsd-dev/contrib/libc-vis/vis.c
Brooks Davis 8ccca1222d Replace our implementation of the vis(3) and unvis(3) APIs with
NetBSD's.  This output size limited versions of vis and unvis functions
as well as a set of vis variants that allow arbitrary characters to be
specified for encoding.

Finally, MIME Quoted-Printable encoding as described in RFC 2045 is
supported.
2012-12-18 16:37:24 +00:00

584 lines
14 KiB
C

/* $NetBSD: vis.c,v 1.45 2012/12/14 21:38:18 christos Exp $ */
/*-
* 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. 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.
*/
/*-
* Copyright (c) 1999, 2005 The NetBSD Foundation, Inc.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: vis.c,v 1.45 2012/12/14 21:38:18 christos Exp $");
#endif /* LIBC_SCCS and not lint */
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <sys/types.h>
#include <assert.h>
#include <vis.h>
#include <errno.h>
#include <stdlib.h>
#define _DIAGASSERT(x) assert(x)
#ifdef __weak_alias
__weak_alias(strvisx,_strvisx)
#endif
#if !HAVE_VIS || !HAVE_SVIS
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
static char *do_svis(char *, size_t *, int, int, int, const char *);
#undef BELL
#define BELL '\a'
#define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
#define iswhite(c) (c == ' ' || c == '\t' || c == '\n')
#define issafe(c) (c == '\b' || c == BELL || c == '\r')
#define xtoa(c) "0123456789abcdef"[c]
#define XTOA(c) "0123456789ABCDEF"[c]
#define MAXEXTRAS 9
#define MAKEEXTRALIST(flag, extra, orig_str) \
do { \
const char *orig = orig_str; \
const char *o = orig; \
char *e; \
while (*o++) \
continue; \
extra = malloc((size_t)((o - orig) + MAXEXTRAS)); \
if (!extra) break; \
for (o = orig, e = extra; (*e++ = *o++) != '\0';) \
continue; \
e--; \
if (flag & VIS_GLOB) { \
*e++ = '*'; \
*e++ = '?'; \
*e++ = '['; \
*e++ = '#'; \
} \
if (flag & VIS_SP) *e++ = ' '; \
if (flag & VIS_TAB) *e++ = '\t'; \
if (flag & VIS_NL) *e++ = '\n'; \
if ((flag & VIS_NOSLASH) == 0) *e++ = '\\'; \
*e = '\0'; \
} while (/*CONSTCOND*/0)
/*
* This is do_hvis, for HTTP style (RFC 1808)
*/
static char *
do_hvis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra)
{
if ((isascii(c) && isalnum(c))
/* safe */
|| c == '$' || c == '-' || c == '_' || c == '.' || c == '+'
/* extra */
|| c == '!' || c == '*' || c == '\'' || c == '(' || c == ')'
|| c == ',') {
dst = do_svis(dst, dlen, c, flag, nextc, extra);
} else {
if (dlen) {
if (*dlen < 3)
return NULL;
*dlen -= 3;
}
*dst++ = '%';
*dst++ = xtoa(((unsigned int)c >> 4) & 0xf);
*dst++ = xtoa((unsigned int)c & 0xf);
}
return dst;
}
/*
* This is do_mvis, for Quoted-Printable MIME (RFC 2045)
* NB: No handling of long lines or CRLF.
*/
static char *
do_mvis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra)
{
if ((c != '\n') &&
/* Space at the end of the line */
((isspace(c) && (nextc == '\r' || nextc == '\n')) ||
/* Out of range */
(!isspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) ||
/* Specific char to be escaped */
strchr("#$@[\\]^`{|}~", c) != NULL)) {
if (dlen) {
if (*dlen < 3)
return NULL;
*dlen -= 3;
}
*dst++ = '=';
*dst++ = XTOA(((unsigned int)c >> 4) & 0xf);
*dst++ = XTOA((unsigned int)c & 0xf);
} else {
dst = do_svis(dst, dlen, c, flag, nextc, extra);
}
return dst;
}
/*
* This is do_vis, the central code of vis.
* dst: Pointer to the destination buffer
* c: Character to encode
* flag: Flag word
* nextc: The character following 'c'
* extra: Pointer to the list of extra characters to be
* backslash-protected.
*/
static char *
do_svis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra)
{
int isextra;
size_t odlen = dlen ? *dlen : 0;
isextra = strchr(extra, c) != NULL;
#define HAVE(x) \
do { \
if (dlen) { \
if (*dlen < (x)) \
goto out; \
*dlen -= (x); \
} \
} while (/*CONSTCOND*/0)
if (!isextra && isascii(c) && (isgraph(c) || iswhite(c) ||
((flag & VIS_SAFE) && issafe(c)))) {
HAVE(1);
*dst++ = c;
return dst;
}
if (flag & VIS_CSTYLE) {
HAVE(2);
switch (c) {
case '\n':
*dst++ = '\\'; *dst++ = 'n';
return dst;
case '\r':
*dst++ = '\\'; *dst++ = 'r';
return dst;
case '\b':
*dst++ = '\\'; *dst++ = 'b';
return dst;
case BELL:
*dst++ = '\\'; *dst++ = 'a';
return dst;
case '\v':
*dst++ = '\\'; *dst++ = 'v';
return dst;
case '\t':
*dst++ = '\\'; *dst++ = 't';
return dst;
case '\f':
*dst++ = '\\'; *dst++ = 'f';
return dst;
case ' ':
*dst++ = '\\'; *dst++ = 's';
return dst;
case '\0':
*dst++ = '\\'; *dst++ = '0';
if (isoctal(nextc)) {
HAVE(2);
*dst++ = '0';
*dst++ = '0';
}
return dst;
default:
if (isgraph(c)) {
*dst++ = '\\'; *dst++ = c;
return dst;
}
if (dlen)
*dlen = odlen;
}
}
if (isextra || ((c & 0177) == ' ') || (flag & VIS_OCTAL)) {
HAVE(4);
*dst++ = '\\';
*dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + '0';
*dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + '0';
*dst++ = (c & 07) + '0';
} else {
if ((flag & VIS_NOSLASH) == 0) {
HAVE(1);
*dst++ = '\\';
}
if (c & 0200) {
HAVE(1);
c &= 0177; *dst++ = 'M';
}
if (iscntrl(c)) {
HAVE(2);
*dst++ = '^';
if (c == 0177)
*dst++ = '?';
else
*dst++ = c + '@';
} else {
HAVE(2);
*dst++ = '-'; *dst++ = c;
}
}
return dst;
out:
*dlen = odlen;
return NULL;
}
typedef char *(*visfun_t)(char *, size_t *, int, int, int, const char *);
/*
* Return the appropriate encoding function depending on the flags given.
*/
static visfun_t
getvisfun(int flag)
{
if (flag & VIS_HTTPSTYLE)
return do_hvis;
if (flag & VIS_MIMESTYLE)
return do_mvis;
return do_svis;
}
/*
* isnvis - visually encode characters, also encoding the characters
* pointed to by `extra'
*/
static char *
isnvis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra)
{
char *nextra = NULL;
visfun_t f;
_DIAGASSERT(dst != NULL);
_DIAGASSERT(extra != NULL);
MAKEEXTRALIST(flag, nextra, extra);
if (!nextra) {
if (dlen && *dlen == 0) {
errno = ENOSPC;
return NULL;
}
*dst = '\0'; /* can't create nextra, return "" */
return dst;
}
f = getvisfun(flag);
dst = (*f)(dst, dlen, c, flag, nextc, nextra);
free(nextra);
if (dst == NULL || (dlen && *dlen == 0)) {
errno = ENOSPC;
return NULL;
}
*dst = '\0';
return dst;
}
char *
svis(char *dst, int c, int flag, int nextc, const char *extra)
{
return isnvis(dst, NULL, c, flag, nextc, extra);
}
char *
snvis(char *dst, size_t dlen, int c, int flag, int nextc, const char *extra)
{
return isnvis(dst, &dlen, c, flag, nextc, extra);
}
/*
* strsvis, strsvisx - visually encode characters from src into dst
*
* Extra is a pointer to a \0-terminated list of characters to
* be encoded, too. These functions are useful e. g. to
* encode strings in such a way so that they are not interpreted
* by a shell.
*
* 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.
*
* Strsvisx encodes exactly len bytes from src into dst.
* This is useful for encoding a block of data.
*/
static int
istrsnvis(char *dst, size_t *dlen, const char *csrc, int flag, const char *extra)
{
int c;
char *start;
char *nextra = NULL;
const unsigned char *src = (const unsigned char *)csrc;
visfun_t f;
_DIAGASSERT(dst != NULL);
_DIAGASSERT(src != NULL);
_DIAGASSERT(extra != NULL);
MAKEEXTRALIST(flag, nextra, extra);
if (!nextra) {
*dst = '\0'; /* can't create nextra, return "" */
return 0;
}
f = getvisfun(flag);
for (start = dst; (c = *src++) != '\0'; /* empty */) {
dst = (*f)(dst, dlen, c, flag, *src, nextra);
if (dst == NULL) {
errno = ENOSPC;
return -1;
}
}
free(nextra);
if (dlen && *dlen == 0) {
errno = ENOSPC;
return -1;
}
*dst = '\0';
return (int)(dst - start);
}
int
strsvis(char *dst, const char *csrc, int flag, const char *extra)
{
return istrsnvis(dst, NULL, csrc, flag, extra);
}
int
strsnvis(char *dst, size_t dlen, const char *csrc, int flag, const char *extra)
{
return istrsnvis(dst, &dlen, csrc, flag, extra);
}
static int
istrsnvisx(char *dst, size_t *dlen, const char *csrc, size_t len, int flag,
const char *extra)
{
unsigned char c;
char *start;
char *nextra = NULL;
const unsigned char *src = (const unsigned char *)csrc;
visfun_t f;
_DIAGASSERT(dst != NULL);
_DIAGASSERT(src != NULL);
_DIAGASSERT(extra != NULL);
MAKEEXTRALIST(flag, nextra, extra);
if (! nextra) {
if (dlen && *dlen == 0) {
errno = ENOSPC;
return -1;
}
*dst = '\0'; /* can't create nextra, return "" */
return 0;
}
f = getvisfun(flag);
for (start = dst; len > 0; len--) {
c = *src++;
dst = (*f)(dst, dlen, c, flag, len > 1 ? *src : '\0', nextra);
if (dst == NULL) {
errno = ENOSPC;
return -1;
}
}
free(nextra);
if (dlen && *dlen == 0) {
errno = ENOSPC;
return -1;
}
*dst = '\0';
return (int)(dst - start);
}
int
strsvisx(char *dst, const char *csrc, size_t len, int flag, const char *extra)
{
return istrsnvisx(dst, NULL, csrc, len, flag, extra);
}
int
strsnvisx(char *dst, size_t dlen, const char *csrc, size_t len, int flag,
const char *extra)
{
return istrsnvisx(dst, &dlen, csrc, len, flag, extra);
}
#endif
#if !HAVE_VIS
/*
* vis - visually encode characters
*/
static char *
invis(char *dst, size_t *dlen, int c, int flag, int nextc)
{
char *extra = NULL;
unsigned char uc = (unsigned char)c;
visfun_t f;
_DIAGASSERT(dst != NULL);
MAKEEXTRALIST(flag, extra, "");
if (! extra) {
if (dlen && *dlen == 0) {
errno = ENOSPC;
return NULL;
}
*dst = '\0'; /* can't create extra, return "" */
return dst;
}
f = getvisfun(flag);
dst = (*f)(dst, dlen, uc, flag, nextc, extra);
free(extra);
if (dst == NULL || (dlen && *dlen == 0)) {
errno = ENOSPC;
return NULL;
}
*dst = '\0';
return dst;
}
char *
vis(char *dst, int c, int flag, int nextc)
{
return invis(dst, NULL, c, flag, nextc);
}
char *
nvis(char *dst, size_t dlen, int c, int flag, int nextc)
{
return invis(dst, &dlen, c, flag, nextc);
}
/*
* 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.
*/
static int
istrnvis(char *dst, size_t *dlen, const char *src, int flag)
{
char *extra = NULL;
int rv;
MAKEEXTRALIST(flag, extra, "");
if (!extra) {
if (dlen && *dlen == 0) {
errno = ENOSPC;
return -1;
}
*dst = '\0'; /* can't create extra, return "" */
return 0;
}
rv = istrsnvis(dst, dlen, src, flag, extra);
free(extra);
return rv;
}
int
strvis(char *dst, const char *src, int flag)
{
return istrnvis(dst, NULL, src, flag);
}
int
strnvis(char *dst, size_t dlen, const char *src, int flag)
{
return istrnvis(dst, &dlen, src, flag);
}
static int
istrnvisx(char *dst, size_t *dlen, const char *src, size_t len, int flag)
{
char *extra = NULL;
int rv;
MAKEEXTRALIST(flag, extra, "");
if (!extra) {
if (dlen && *dlen == 0) {
errno = ENOSPC;
return -1;
}
*dst = '\0'; /* can't create extra, return "" */
return 0;
}
rv = istrsnvisx(dst, dlen, src, len, flag, extra);
free(extra);
return rv;
}
int
strvisx(char *dst, const char *src, size_t len, int flag)
{
return istrnvisx(dst, NULL, src, len, flag);
}
int
strnvisx(char *dst, size_t dlen, const char *src, size_t len, int flag)
{
return istrnvisx(dst, &dlen, src, len, flag);
}
#endif