freebsd-dev/lib/libc/string/strerror.c
Jilles Tjoelker e73151eb82 libc: Always use our own copy of sys_errlist and sys_nerr (.so only).
This ensures strerror() and friends continue to work correctly even if a
(non-PIE) executable linked against an older libc imports sys_errlist (which
causes sys_errlist to refer to the executable's copy with a size fixed when
that executable was linked).

The executable's use of sys_errlist remains broken because it uses the
current value of sys_nerr and may access past the bounds of the array.

Different from the message "Using sys_errlist from executables is not
ABI-stable" on freebsd-arch, this change does not affect the static library.
There seems no reason to prevent overriding the error messages in the static
library.
2013-08-31 22:32:42 +00:00

129 lines
3.4 KiB
C

/*-
* Copyright (c) 1988, 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)strerror.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#if defined(NLS)
#include <nl_types.h>
#endif
#include <limits.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include "errlst.h"
#define UPREFIX "Unknown error"
/*
* Define a buffer size big enough to describe a 64-bit signed integer
* converted to ASCII decimal (19 bytes), with an optional leading sign
* (1 byte); finally, we get the prefix, delimiter (": ") and a trailing
* NUL from UPREFIX.
*/
#define EBUFSIZE (20 + 2 + sizeof(UPREFIX))
/*
* Doing this by hand instead of linking with stdio(3) avoids bloat for
* statically linked binaries.
*/
static void
errstr(int num, char *uprefix, char *buf, size_t len)
{
char *t;
unsigned int uerr;
char tmp[EBUFSIZE];
t = tmp + sizeof(tmp);
*--t = '\0';
uerr = (num >= 0) ? num : -num;
do {
*--t = "0123456789"[uerr % 10];
} while (uerr /= 10);
if (num < 0)
*--t = '-';
*--t = ' ';
*--t = ':';
strlcpy(buf, uprefix, len);
strlcat(buf, t, len);
}
int
strerror_r(int errnum, char *strerrbuf, size_t buflen)
{
int retval = 0;
#if defined(NLS)
int saved_errno = errno;
nl_catd catd;
catd = catopen("libc", NL_CAT_LOCALE);
#endif
if (errnum < 0 || errnum >= __hidden_sys_nerr) {
errstr(errnum,
#if defined(NLS)
catgets(catd, 1, 0xffff, UPREFIX),
#else
UPREFIX,
#endif
strerrbuf, buflen);
retval = EINVAL;
} else {
if (strlcpy(strerrbuf,
#if defined(NLS)
catgets(catd, 1, errnum, __hidden_sys_errlist[errnum]),
#else
__hidden_sys_errlist[errnum],
#endif
buflen) >= buflen)
retval = ERANGE;
}
#if defined(NLS)
catclose(catd);
errno = saved_errno;
#endif
return (retval);
}
char *
strerror(int num)
{
static char ebuf[NL_TEXTMAX];
if (strerror_r(num, ebuf, sizeof(ebuf)) != 0)
errno = EINVAL;
return (ebuf);
}