freebsd-dev/lib/libc/stdlib/set_constraint_handler_s.c
Konstantin Belousov 25b73e6327 Improve standard compliance for memset_s() and abort_handler_s().
abort_handler_s() currently simply calls abort(), though the standard
specifies more: "Writes an implementation-defined message to stderr
which must include the string pointed to by msg and calls abort()."

memset_s() is missing error condition "n > smax", and does not invoke
the constraint handler after filling the buffer: "following errors are
detected at runtime and call the currently installed constraint
handler function after storing ch in every location of the destination
range [dest, dest+destsz) if dest and destsz are themselves valid",
one of the errors is "n > smax" itself.

Submitted by:	Yuri Pankov <yuripv@gmx.com>
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D11991
2017-08-12 15:18:17 +00:00

102 lines
2.9 KiB
C

/*-
* Copyright (c) 2017 Juniper Networks. 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 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <sys/types.h>
#include <machine/atomic.h>
#include <errno.h>
#include <pthread.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "un-namespace.h"
#include "libc_private.h"
/*
* Rationale recommends allocating new memory each time.
*/
static constraint_handler_t *_ch = NULL;
static pthread_mutex_t ch_lock = PTHREAD_MUTEX_INITIALIZER;
constraint_handler_t
set_constraint_handler_s(constraint_handler_t handler)
{
constraint_handler_t *new, *old, ret;
new = malloc(sizeof(constraint_handler_t));
if (new == NULL)
return (NULL);
*new = handler;
if (__isthreaded)
_pthread_mutex_lock(&ch_lock);
old = _ch;
_ch = new;
if (__isthreaded)
_pthread_mutex_unlock(&ch_lock);
if (old == NULL) {
ret = NULL;
} else {
ret = *old;
free(old);
}
return (ret);
}
void
__throw_constraint_handler_s(const char * restrict msg, errno_t error)
{
constraint_handler_t ch;
if (__isthreaded)
_pthread_mutex_lock(&ch_lock);
ch = _ch != NULL ? *_ch : NULL;
if (__isthreaded)
_pthread_mutex_unlock(&ch_lock);
if (ch != NULL)
ch(msg, NULL, error);
}
void
abort_handler_s(const char * restrict msg, void * restrict ptr __unused,
errno_t error __unused)
{
static const char ahs[] = "abort_handler_s : ";
(void) _write(STDERR_FILENO, ahs, sizeof(ahs) - 1);
(void) _write(STDERR_FILENO, msg, strlen(msg));
(void) _write(STDERR_FILENO, "\n", 1);
abort();
}
void
ignore_handler_s(const char * restrict msg __unused,
void * restrict ptr __unused, errno_t error __unused)
{
}