hurd: fix compilation of signal.h in C++
[glibc.git] / nss / nss_db / db-open.c
blobc482232b3cdd8df19c5681766414dd88bf68cec1
1 /* Common database routines for nss_db.
2 Copyright (C) 2000-2015 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <dlfcn.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25 #include <sys/mman.h>
26 #include <not-cancel.h>
28 #include "nss_db.h"
30 /* Open the database stored in FILE. If succesful, store either a
31 pointer to the mapped file or a file handle for the file in H and
32 return NSS_STATUS_SUCCESS. On failure, return the appropriate
33 lookup status. */
34 enum nss_status
35 internal_setent (const char *file, struct nss_db_map *mapping)
37 enum nss_status status = NSS_STATUS_UNAVAIL;
39 int mode = O_RDONLY | O_LARGEFILE;
40 #ifdef O_CLOEXEC
41 mode |= O_CLOEXEC;
42 #endif
43 int fd = open_not_cancel_2 (file, mode);
44 if (fd != -1)
46 struct nss_db_header header;
48 if (read (fd, &header, sizeof (header)) == sizeof (header))
50 mapping->header = mmap (NULL, header.allocate, PROT_READ,
51 MAP_PRIVATE, fd, 0);
52 mapping->len = header.allocate;
53 if (mapping->header != MAP_FAILED)
54 status = NSS_STATUS_SUCCESS;
55 else if (errno == ENOMEM)
56 status = NSS_STATUS_TRYAGAIN;
59 close_not_cancel_no_status (fd);
62 return status;
66 /* Close the database. */
67 void
68 internal_endent (struct nss_db_map *mapping)
70 munmap (mapping->header, mapping->len);