/*      $NetBSD: intrctl_io.c,v 1.5 2019/09/23 09:17:19 mrg Exp $       */

/*
 * Copyright (c) 2015 Internet Initiative Japan 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>
__RCSID("$NetBSD: intrctl_io.c,v 1.5 2019/09/23 09:17:19 mrg Exp $");

#include <sys/sysctl.h>
#include <sys/intrio.h>

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

#include "intrctl_io.h"

/*
 * To support increasing the number of interrupts (devices are dynamically
 * attached), retry sysctl(3) "retry" times.
 */
void *
intrctl_io_alloc(int retry)
{
        size_t buf_size;
        int i, error;
        void *buf = NULL;

        error = sysctlbyname("kern.intr.list", NULL, &buf_size, NULL, 0);
        if (error < 0) {
                goto error;
        }

        buf = malloc(buf_size);
        if (buf == NULL) {
                goto error;
        }

        for (i = 0; i < retry; i++) {
                error = sysctlbyname("kern.intr.list", buf, &buf_size, NULL, 0);
                if (error >= 0)
                        return buf;
                else if (errno == ENOMEM) {
                        void *temp;

                        temp = realloc(buf, buf_size);
                        if (temp == NULL) {
                                goto error;
                        }
                        buf = temp;
                } else {
                        goto error;
                }
        }
error:
        free(buf);
        return NULL;
}

void
intrctl_io_free(void *handle)
{

        free(handle);
}

int
intrctl_io_ncpus(void *handle)
{
        struct intrio_list *list = handle;

        return list->il_ncpus;
}

int
intrctl_io_nintrs(void *handle)
{
        struct intrio_list *list = handle;

        return list->il_nintrs;
}

struct intrio_list_line *
intrctl_io_firstline(void *handle)
{
        struct intrio_list *list = handle;
        struct intrio_list_line *next;
        char *buf_end;

        buf_end = (char *)list + list->il_bufsize;
        next = (struct intrio_list_line *)((char *)list + list->il_lineoffset);
        if ((char *)next >= buf_end)
                return NULL;

        return next;
}

struct intrio_list_line *
intrctl_io_nextline(void *handle, struct intrio_list_line *cur)
{
        struct intrio_list *list;
        struct intrio_list_line *next;
        size_t line_size;
        char *buf_end;

        list = handle;
        buf_end = (char *)list + list->il_bufsize;

        line_size = list->il_linesize;
        next = (struct intrio_list_line *)((char *)cur + line_size);
        if ((char *)next >= buf_end)
                return NULL;

        return next;
}