/*
 * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
 * 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 Hyra 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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/panic.h>
#include <sys/spinlock.h>
#include <sys/syslog.h>
#include <sys/reboot.h>

/*
 * Tells the user something terribly wrong happened then
 * halting the system as soon as possible.
 *
 * XXX: There is no need to cleanup stuff here (e.g `va_list ap`)
 *      as we won't be returning from here anyways and the source
 *      of the panic could be *anywhere* so it's best not to mess with
 *      things.
 */
void
panic(const char *fmt, ...)
{
    va_list ap;
    static struct spinlock lock = {0};

    spinlock_acquire(&lock);    /* Never released */
    va_start(ap, fmt);

    kprintf(OMIT_TIMESTAMP "panic: ");
    vkprintf(fmt, &ap);

    kprintf(OMIT_TIMESTAMP "** backtrace\n");
    md_backtrace();

    cpu_reboot(REBOOT_HALT);
    __builtin_unreachable();
}