freebsd-dev/contrib/libc-vis/vis.c
Brooks Davis ac25e23856 Merge from NetBSD:
PR/49185: Conrad Meyer: strvisx: Handle zero-length input strings
gracefully.  (don't abuse 0 to mean compute string length internally)

PR:		193447
Submitted by:	Conrad Meyer <conrad.meyer@isilon.com>
MFC after:	1 month
2014-09-08 19:26:21 +00:00

695 lines
18 KiB
C

/* $NetBSD: vis.c,v 1.62 2014/09/08 17:35:01 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 1.62 2014/09/08 17:35:01 christos Exp $");
#endif /* LIBC_SCCS and not lint */
#ifdef __FBSDID
__FBSDID("$FreeBSD$");
#define _DIAGASSERT(x) assert(x)
#endif
#include "namespace.h"
#include <sys/types.h>
#include <sys/param.h>
#include <assert.h>
#include <vis.h>
#include <errno.h>
#include <stdlib.h>
#include <wchar.h>
#include <wctype.h>
#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>
/*
* The reason for going through the trouble to deal with character encodings
* in vis(3), is that we use this to safe encode output of commands. This
* safe encoding varies depending on the character set. For example if we
* display ps output in French, we don't want to display French characters
* as M-foo.
*/
static wchar_t *do_svis(wchar_t *, wint_t, int, wint_t, const wchar_t *);
#undef BELL
#define BELL L'\a'
#define iswoctal(c) (((u_char)(c)) >= L'0' && ((u_char)(c)) <= L'7')
#define iswwhite(c) (c == L' ' || c == L'\t' || c == L'\n')
#define iswsafe(c) (c == L'\b' || c == BELL || c == L'\r')
#define xtoa(c) L"0123456789abcdef"[c]
#define XTOA(c) L"0123456789ABCDEF"[c]
#define MAXEXTRAS 10
#if !HAVE_NBTOOL_CONFIG_H
#ifndef __NetBSD__
/*
* On NetBSD MB_LEN_MAX is currently 32 which does not fit on any integer
* integral type and it is probably wrong, since currently the maximum
* number of bytes and character needs is 6. Until this is fixed, the
* loops below are using sizeof(uint64_t) - 1 instead of MB_LEN_MAX, and
* the assertion is commented out.
*/
#ifdef __FreeBSD__
/*
* On FreeBSD including <sys/systm.h> for CTASSERT only works in kernel
* mode.
*/
#ifndef CTASSERT
#define CTASSERT(x) _CTASSERT(x, __LINE__)
#define _CTASSERT(x, y) __CTASSERT(x, y)
#define __CTASSERT(x, y) typedef char __assert ## y[(x) ? 1 : -1]
#endif
#endif /* __FreeBSD__ */
CTASSERT(MB_LEN_MAX <= sizeof(uint64_t));
#endif /* !__NetBSD__ */
#endif
/*
* This is do_hvis, for HTTP style (RFC 1808)
*/
static wchar_t *
do_hvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
{
if (iswalnum(c)
/* safe */
|| c == L'$' || c == L'-' || c == L'_' || c == L'.' || c == L'+'
/* extra */
|| c == L'!' || c == L'*' || c == L'\'' || c == L'(' || c == L')'
|| c == L',')
dst = do_svis(dst, c, flags, nextc, extra);
else {
*dst++ = L'%';
*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 wchar_t *
do_mvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
{
if ((c != L'\n') &&
/* Space at the end of the line */
((iswspace(c) && (nextc == L'\r' || nextc == L'\n')) ||
/* Out of range */
(!iswspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) ||
/* Specific char to be escaped */
wcschr(L"#$@[\\]^`{|}~", c) != NULL)) {
*dst++ = L'=';
*dst++ = XTOA(((unsigned int)c >> 4) & 0xf);
*dst++ = XTOA((unsigned int)c & 0xf);
} else
dst = do_svis(dst, c, flags, nextc, extra);
return dst;
}
/*
* Output single byte of multibyte character.
*/
static wchar_t *
do_mbyte(wchar_t *dst, wint_t c, int flags, wint_t nextc, int iswextra)
{
if (flags & VIS_CSTYLE) {
switch (c) {
case L'\n':
*dst++ = L'\\'; *dst++ = L'n';
return dst;
case L'\r':
*dst++ = L'\\'; *dst++ = L'r';
return dst;
case L'\b':
*dst++ = L'\\'; *dst++ = L'b';
return dst;
case BELL:
*dst++ = L'\\'; *dst++ = L'a';
return dst;
case L'\v':
*dst++ = L'\\'; *dst++ = L'v';
return dst;
case L'\t':
*dst++ = L'\\'; *dst++ = L't';
return dst;
case L'\f':
*dst++ = L'\\'; *dst++ = L'f';
return dst;
case L' ':
*dst++ = L'\\'; *dst++ = L's';
return dst;
case L'\0':
*dst++ = L'\\'; *dst++ = L'0';
if (iswoctal(nextc)) {
*dst++ = L'0';
*dst++ = L'0';
}
return dst;
default:
if (iswgraph(c)) {
*dst++ = L'\\';
*dst++ = c;
return dst;
}
}
}
if (iswextra || ((c & 0177) == L' ') || (flags & VIS_OCTAL)) {
*dst++ = L'\\';
*dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + L'0';
*dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + L'0';
*dst++ = (c & 07) + L'0';
} else {
if ((flags & VIS_NOSLASH) == 0)
*dst++ = L'\\';
if (c & 0200) {
c &= 0177;
*dst++ = L'M';
}
if (iswcntrl(c)) {
*dst++ = L'^';
if (c == 0177)
*dst++ = L'?';
else
*dst++ = c + L'@';
} else {
*dst++ = L'-';
*dst++ = c;
}
}
return dst;
}
/*
* This is do_vis, the central code of vis.
* dst: Pointer to the destination buffer
* c: Character to encode
* flags: Flags word
* nextc: The character following 'c'
* extra: Pointer to the list of extra characters to be
* backslash-protected.
*/
static wchar_t *
do_svis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
{
int iswextra, i, shft;
uint64_t bmsk, wmsk;
iswextra = wcschr(extra, c) != NULL;
if (!iswextra && (iswgraph(c) || iswwhite(c) ||
((flags & VIS_SAFE) && iswsafe(c)))) {
*dst++ = c;
return dst;
}
/* See comment in istrsenvisx() output loop, below. */
wmsk = 0;
for (i = sizeof(wmsk) - 1; i >= 0; i--) {
shft = i * NBBY;
bmsk = (uint64_t)0xffLL << shft;
wmsk |= bmsk;
if ((c & wmsk) || i == 0)
dst = do_mbyte(dst, (wint_t)(
(uint64_t)(c & bmsk) >> shft),
flags, nextc, iswextra);
}
return dst;
}
typedef wchar_t *(*visfun_t)(wchar_t *, wint_t, int, wint_t, const wchar_t *);
/*
* Return the appropriate encoding function depending on the flags given.
*/
static visfun_t
getvisfun(int flags)
{
if (flags & VIS_HTTPSTYLE)
return do_hvis;
if (flags & VIS_MIMESTYLE)
return do_mvis;
return do_svis;
}
/*
* Expand list of extra characters to not visually encode.
*/
static wchar_t *
makeextralist(int flags, const char *src)
{
wchar_t *dst, *d;
size_t len;
len = strlen(src);
if ((dst = calloc(len + MAXEXTRAS, sizeof(*dst))) == NULL)
return NULL;
if (mbstowcs(dst, src, len) == (size_t)-1) {
size_t i;
for (i = 0; i < len; i++)
dst[i] = (wint_t)(u_char)src[i];
d = dst + len;
} else
d = dst + wcslen(dst);
if (flags & VIS_GLOB) {
*d++ = L'*';
*d++ = L'?';
*d++ = L'[';
*d++ = L'#';
}
if (flags & VIS_SP) *d++ = L' ';
if (flags & VIS_TAB) *d++ = L'\t';
if (flags & VIS_NL) *d++ = L'\n';
if ((flags & VIS_NOSLASH) == 0) *d++ = L'\\';
*d = L'\0';
return dst;
}
/*
* istrsenvisx()
* The main internal function.
* All user-visible functions call this one.
*/
static int
istrsenvisx(char *mbdst, size_t *dlen, const char *mbsrc, size_t mblength,
int flags, const char *mbextra, int *cerr_ptr)
{
wchar_t *dst, *src, *pdst, *psrc, *start, *extra;
size_t len, olen;
uint64_t bmsk, wmsk;
wint_t c;
visfun_t f;
int clen = 0, cerr = 0, error = -1, i, shft;
ssize_t mbslength, maxolen;
_DIAGASSERT(mbdst != NULL);
_DIAGASSERT(mbsrc != NULL || mblength == 0);
_DIAGASSERT(mbextra != NULL);
/*
* Input (mbsrc) is a char string considered to be multibyte
* characters. The input loop will read this string pulling
* one character, possibly multiple bytes, from mbsrc and
* converting each to wchar_t in src.
*
* The vis conversion will be done using the wide char
* wchar_t string.
*
* This will then be converted back to a multibyte string to
* return to the caller.
*/
/* Allocate space for the wide char strings */
psrc = pdst = extra = NULL;
if ((psrc = calloc(mblength + 1, sizeof(*psrc))) == NULL)
return -1;
if ((pdst = calloc((4 * mblength) + 1, sizeof(*pdst))) == NULL)
goto out;
dst = pdst;
src = psrc;
/* Use caller's multibyte conversion error flag. */
if (cerr_ptr)
cerr = *cerr_ptr;
/*
* Input loop.
* Handle up to mblength characters (not bytes). We do not
* stop at NULs because we may be processing a block of data
* that includes NULs.
*/
mbslength = (ssize_t)mblength;
/*
* When inputing a single character, must also read in the
* next character for nextc, the look-ahead character.
*/
if (mbslength == 1)
mbslength++;
while (mbslength > 0) {
/* Convert one multibyte character to wchar_t. */
if (!cerr)
clen = mbtowc(src, mbsrc, MB_LEN_MAX);
if (cerr || clen < 0) {
/* Conversion error, process as a byte instead. */
*src = (wint_t)(u_char)*mbsrc;
clen = 1;
cerr = 1;
}
if (clen == 0)
/*
* NUL in input gives 0 return value. process
* as single NUL byte and keep going.
*/
clen = 1;
/* Advance buffer character pointer. */
src++;
/* Advance input pointer by number of bytes read. */
mbsrc += clen;
/* Decrement input byte count. */
mbslength -= clen;
}
len = src - psrc;
src = psrc;
/*
* In the single character input case, we will have actually
* processed two characters, c and nextc. Reset len back to
* just a single character.
*/
if (mblength < len)
len = mblength;
/* Convert extra argument to list of characters for this mode. */
extra = makeextralist(flags, mbextra);
if (!extra) {
if (dlen && *dlen == 0) {
errno = ENOSPC;
goto out;
}
*mbdst = '\0'; /* can't create extra, return "" */
error = 0;
goto out;
}
/* Look up which processing function to call. */
f = getvisfun(flags);
/*
* Main processing loop.
* Call do_Xvis processing function one character at a time
* with next character available for look-ahead.
*/
for (start = dst; len > 0; len--) {
c = *src++;
dst = (*f)(dst, c, flags, len >= 1 ? *src : L'\0', extra);
if (dst == NULL) {
errno = ENOSPC;
goto out;
}
}
/* Terminate the string in the buffer. */
*dst = L'\0';
/*
* Output loop.
* Convert wchar_t string back to multibyte output string.
* If we have hit a multi-byte conversion error on input,
* output byte-by-byte here. Else use wctomb().
*/
len = wcslen(start);
maxolen = dlen ? *dlen : (wcslen(start) * MB_LEN_MAX + 1);
olen = 0;
for (dst = start; len > 0; len--) {
if (!cerr)
clen = wctomb(mbdst, *dst);
if (cerr || clen < 0) {
/*
* Conversion error, process as a byte(s) instead.
* Examine each byte and higher-order bytes for
* data. E.g.,
* 0x000000000000a264 -> a2 64
* 0x000000001f00a264 -> 1f 00 a2 64
*/
clen = 0;
wmsk = 0;
for (i = sizeof(wmsk) - 1; i >= 0; i--) {
shft = i * NBBY;
bmsk = (uint64_t)0xffLL << shft;
wmsk |= bmsk;
if ((*dst & wmsk) || i == 0)
mbdst[clen++] = (char)(
(uint64_t)(*dst & bmsk) >>
shft);
}
cerr = 1;
}
/* If this character would exceed our output limit, stop. */
if (olen + clen > (size_t)maxolen)
break;
/* Advance output pointer by number of bytes written. */
mbdst += clen;
/* Advance buffer character pointer. */
dst++;
/* Incrment output character count. */
olen += clen;
}
/* Terminate the output string. */
*mbdst = '\0';
/* Pass conversion error flag out. */
if (cerr_ptr)
*cerr_ptr = cerr;
free(extra);
free(pdst);
free(psrc);
return (int)olen;
out:
free(extra);
free(pdst);
free(psrc);
return error;
}
static int
istrsenvisxl(char *mbdst, size_t *dlen, const char *mbsrc,
int flags, const char *mbextra, int *cerr_ptr)
{
return istrsenvisx(mbdst, dlen, mbsrc,
mbsrc != NULL ? strlen(mbsrc) : 0, flags, mbextra, cerr_ptr);
}
#endif
#if !HAVE_SVIS
/*
* The "svis" variants all take an "extra" arg that is a pointer
* to a NUL-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.
*/
char *
svis(char *mbdst, int c, int flags, int nextc, const char *mbextra)
{
char cc[2];
int ret;
cc[0] = c;
cc[1] = nextc;
ret = istrsenvisx(mbdst, NULL, cc, 1, flags, mbextra, NULL);
if (ret < 0)
return NULL;
return mbdst + ret;
}
char *
snvis(char *mbdst, size_t dlen, int c, int flags, int nextc, const char *mbextra)
{
char cc[2];
int ret;
cc[0] = c;
cc[1] = nextc;
ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, mbextra, NULL);
if (ret < 0)
return NULL;
return mbdst + ret;
}
int
strsvis(char *mbdst, const char *mbsrc, int flags, const char *mbextra)
{
return istrsenvisxl(mbdst, NULL, mbsrc, flags, mbextra, NULL);
}
int
strsnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags, const char *mbextra)
{
return istrsenvisxl(mbdst, &dlen, mbsrc, flags, mbextra, NULL);
}
int
strsvisx(char *mbdst, const char *mbsrc, size_t len, int flags, const char *mbextra)
{
return istrsenvisx(mbdst, NULL, mbsrc, len, flags, mbextra, NULL);
}
int
strsnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
const char *mbextra)
{
return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, NULL);
}
int
strsenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
const char *mbextra, int *cerr_ptr)
{
return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, cerr_ptr);
}
#endif
#if !HAVE_VIS
/*
* vis - visually encode characters
*/
char *
vis(char *mbdst, int c, int flags, int nextc)
{
char cc[2];
int ret;
cc[0] = c;
cc[1] = nextc;
ret = istrsenvisx(mbdst, NULL, cc, 1, flags, "", NULL);
if (ret < 0)
return NULL;
return mbdst + ret;
}
char *
nvis(char *mbdst, size_t dlen, int c, int flags, int nextc)
{
char cc[2];
int ret;
cc[0] = c;
cc[1] = nextc;
ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, "", NULL);
if (ret < 0)
return NULL;
return mbdst + ret;
}
/*
* strvis - 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.
*/
int
strvis(char *mbdst, const char *mbsrc, int flags)
{
return istrsenvisxl(mbdst, NULL, mbsrc, flags, "", NULL);
}
int
strnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags)
{
return istrsenvisxl(mbdst, &dlen, mbsrc, flags, "", NULL);
}
/*
* 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 characters from src into dst.
* This is useful for encoding a block of data.
*/
int
strvisx(char *mbdst, const char *mbsrc, size_t len, int flags)
{
return istrsenvisx(mbdst, NULL, mbsrc, len, flags, "", NULL);
}
int
strnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags)
{
return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", NULL);
}
int
strenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
int *cerr_ptr)
{
return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", cerr_ptr);
}
#endif