/*      $NetBSD: citrus_mmap.c,v 1.5 2017/01/10 16:51:30 christos Exp $ */

/*-
* Copyright (c)2003 Citrus Project,
* 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 AUTHOR 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 AUTHOR 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>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: citrus_mmap.c,v 1.5 2017/01/10 16:51:30 christos Exp $");
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"

#include <sys/mman.h>
#include <sys/stat.h>

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <limits.h>

#include "citrus_namespace.h"
#include "citrus_region.h"
#include "citrus_mmap.h"

int
_citrus_map_file(struct _citrus_region * __restrict r,
   const char * __restrict path)
{
       int fd, ret = 0;
       struct stat st;
       void *head;

       _DIAGASSERT(r != NULL);

       _region_init(r, NULL, 0);

       if ((fd = open(path, O_RDONLY | O_CLOEXEC)) == -1)
               return errno;

       if (fstat(fd, &st)  == -1) {
               ret = errno;
               goto error;
       }
       if (!S_ISREG(st.st_mode)) {
               ret = EOPNOTSUPP;
               goto error;
       }

       head = mmap(NULL, (size_t)st.st_size, PROT_READ, MAP_FILE|MAP_PRIVATE,
           fd, (off_t)0);
       if (head == MAP_FAILED) {
               ret = errno;
               goto error;
       }
       _region_init(r, head, (size_t)st.st_size);

error:
       (void)close(fd);
       return ret;
}

void
_citrus_unmap_file(struct _citrus_region *r)
{

       _DIAGASSERT(r != NULL);

       if (_region_head(r) != NULL) {
               (void)munmap(_region_head(r), _region_size(r));
               _region_init(r, NULL, 0);
       }
}