1 /* Helper functions for translating between O_* and SOCK_* flags.
2    Copyright (C) 2008-2022 Free Software Foundation, Inc.
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 
20 #include <fcntl.h>
21 #include <sys/socket.h>
22 
23 /* Do some compile-time checks for the SOCK_* constants, which we rely on.  */
24 _Static_assert (SOCK_CLOEXEC == O_CLOEXEC,
25     "SOCK_CLOEXEC is assumed to be the same as O_CLOEXEC");
26 _Static_assert (((SOCK_MAX - 1) | SOCK_TYPE_MASK) == SOCK_TYPE_MASK,
27     "SOCK_TYPE_MASK must contain SOCK_MAX - 1");
28 _Static_assert ((SOCK_CLOEXEC & SOCK_TYPE_MASK) == 0,
29     "SOCK_TYPE_MASK must not contain SOCK_CLOEXEC");
30 _Static_assert ((SOCK_NONBLOCK & SOCK_TYPE_MASK) == 0,
31     "SOCK_TYPE_MASK must not contain SOCK_NONBLOCK");
32 
33 
34 /* Convert from SOCK_* flags to O_* flags.  */
35 __extern_always_inline
36 int
sock_to_o_flags(int in)37 sock_to_o_flags (int in)
38 {
39   int out = 0;
40 
41   if (in & SOCK_NONBLOCK)
42     out |= O_NONBLOCK;
43   /* Others are passed through unfiltered.  */
44   out |= in & ~(SOCK_NONBLOCK);
45 
46   return out;
47 }
48 
49 /* Convert from O_* flags to SOCK_* flags.  */
50 __extern_always_inline
51 int
o_to_sock_flags(int in)52 o_to_sock_flags (int in)
53 {
54   int out = 0;
55 
56   if (in & O_NONBLOCK)
57     out |= SOCK_NONBLOCK;
58   /* Others are passed through unfiltered.  */
59   out |= in & ~(O_NONBLOCK);
60 
61   return out;
62 }
63