/*      $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;
}