root/usr/src/lib/libc/port/gen/set_constraint_handler_s.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.
 */

/*
 * Copyright 2018 Nexenta Systems, Inc.
 */

#define __STDC_WANT_LIB_EXT1__  1

#include "lint.h"

#include <sys/types.h>
#include <errno.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <synch.h>
#include <thread.h>
#include <unistd.h>

#include "libc.h"

/*
 * Rationale recommends allocating new memory each time.
 */
static constraint_handler_t *_ch = NULL;
static mutex_t ch_lock = ERRORCHECKMUTEX;

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;
        mutex_enter(&ch_lock);
        old = _ch;
        _ch = new;
        mutex_exit(&ch_lock);
        if (old == NULL) {
                ret = NULL;
        } else {
                ret = *old;
                free(old);
        }
        return (ret);
}

void
abort_handler_s(const char *_RESTRICT_KYWD msg,
    void *_RESTRICT_KYWD ptr __unused, errno_t error __unused)
{
        common_panic("abort_handler_s: ", msg);
}

void
ignore_handler_s(const char *_RESTRICT_KYWD msg __unused,
    void *_RESTRICT_KYWD ptr __unused, errno_t error __unused)
{
}

void
__throw_constraint_handler_s(const char *_RESTRICT_KYWD msg, errno_t error)
{
        constraint_handler_t ch;

        mutex_enter(&ch_lock);
        ch = (_ch != NULL) ? *_ch : NULL;
        mutex_exit(&ch_lock);
        if (ch != NULL) {
                ch(msg, NULL, error);
        } else {
                /*
                 * If current handler is NULL (there were no calls to
                 * set_constraint_handler_s(), or it was called with NULL
                 * pointer handler argument), call default constraint handler
                 * per K.3.6.1.1 points 4 and 5.
                 *
                 * This implementation defines abort_handler_s() as default.
                 */
                abort_handler_s(msg, NULL, error);
        }
}