1 /* Copyright (C) 1991-2022 Free Software Foundation, Inc.
2
3 This file is part of the GNU C Library.
4
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.
9
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.
14
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 <https://www.gnu.org/licenses/>. */
18
19 #include <hurd.h>
20
21 /* This is initialized in dtable.c when that gets linked in.
22 If dtable.c is not linked in, it will be zero. */
23 static file_t (*_default_hurd_getdport_fn) (int fd) = 0;
weak_alias(_default_hurd_getdport_fn,_hurd_getdport_fn)24 weak_alias (_default_hurd_getdport_fn, _hurd_getdport_fn)
25
26 file_t
27 __getdport (int fd)
28 {
29 if (_hurd_getdport_fn)
30 /* dtable.c has defined the function to fetch a port from the real file
31 descriptor table. */
32 return (*_hurd_getdport_fn) (fd);
33
34 /* getdport is the only use of file descriptors,
35 so we don't bother allocating a real table. */
36
37 if (_hurd_init_dtable == NULL)
38 {
39 /* Never had a descriptor table. */
40 errno = EBADF;
41 return MACH_PORT_NULL;
42 }
43
44 if (fd < 0 || (unsigned int) fd > _hurd_init_dtablesize
45 || _hurd_init_dtable[fd] == MACH_PORT_NULL)
46 {
47 errno = EBADF;
48 return MACH_PORT_NULL;
49 }
50 else
51 {
52 __mach_port_mod_refs (__mach_task_self (), _hurd_init_dtable[fd],
53 MACH_PORT_RIGHT_SEND, 1);
54 return _hurd_init_dtable[fd];
55 }
56 }
57
58 weak_alias (__getdport, getdport)
59