/*	$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 <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);
  }
}
