1 | /* Copyright (C) 2011-2017 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | Contributed by Ulrich Drepper <drepper@gmail.com>, 2011. |
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 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <errno.h> |
20 | #include <sys/socket.h> |
21 | |
22 | #include <sysdep-cancel.h> |
23 | #include <sys/syscall.h> |
24 | #include <kernel-features.h> |
25 | |
26 | /* Do not use the sendmmsg syscall on socketcall architectures unless |
27 | it was added at the same time as the socketcall support or can be |
28 | assumed to be present. */ |
29 | #if defined __ASSUME_SOCKETCALL \ |
30 | && !defined __ASSUME_SENDMMSG_SYSCALL_WITH_SOCKETCALL \ |
31 | && !defined __ASSUME_SENDMMSG_SYSCALL |
32 | # undef __NR_sendmmsg |
33 | #endif |
34 | |
35 | #ifdef __NR_sendmmsg |
36 | int |
37 | __sendmmsg (int fd, struct mmsghdr *vmessages, unsigned int vlen, int flags) |
38 | { |
39 | return SYSCALL_CANCEL (sendmmsg, fd, vmessages, vlen, flags); |
40 | } |
41 | libc_hidden_def (__sendmmsg) |
42 | weak_alias (__sendmmsg, sendmmsg) |
43 | #elif defined __NR_socketcall |
44 | # include <socketcall.h> |
45 | # ifdef __ASSUME_SENDMMSG_SOCKETCALL |
46 | int |
47 | __sendmmsg (int fd, struct mmsghdr *vmessages, unsigned int vlen, int flags) |
48 | { |
49 | return SOCKETCALL_CANCEL (sendmmsg, fd, vmessages, vlen, flags); |
50 | } |
51 | # else |
52 | static int have_sendmmsg; |
53 | |
54 | int |
55 | __sendmmsg (int fd, struct mmsghdr *vmessages, unsigned int vlen, int flags) |
56 | { |
57 | if (__glibc_likely (have_sendmmsg >= 0)) |
58 | { |
59 | int ret = SOCKETCALL_CANCEL (sendmmsg, fd, vmessages, vlen, flags); |
60 | /* The kernel returns -EINVAL for unknown socket operations. |
61 | We need to convert that error to an ENOSYS error. */ |
62 | if (__builtin_expect (ret < 0, 0) |
63 | && have_sendmmsg == 0 |
64 | && errno == EINVAL) |
65 | { |
66 | /* Try another call, this time with an invalid file |
67 | descriptor and all other parameters cleared. This call |
68 | will not cause any harm and it will return |
69 | immediately. */ |
70 | ret = SOCKETCALL_CANCEL (invalid, -1); |
71 | if (errno == EINVAL) |
72 | { |
73 | have_sendmmsg = -1; |
74 | __set_errno (ENOSYS); |
75 | } |
76 | else |
77 | { |
78 | have_sendmmsg = 1; |
79 | __set_errno (EINVAL); |
80 | } |
81 | return -1; |
82 | } |
83 | return ret; |
84 | } |
85 | __set_errno (ENOSYS); |
86 | return -1; |
87 | } |
88 | # endif /* __ASSUME_SENDMMSG_SOCKETCALL */ |
89 | libc_hidden_def (__sendmmsg) |
90 | weak_alias (__sendmmsg, sendmmsg) |
91 | #else |
92 | # include <socket/sendmmsg.c> |
93 | #endif |
94 | |