xref: /aosp_15_r20/external/llvm-libc/src/sys/epoll/linux/epoll_ctl.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===---------- Linux implementation of the epoll_ctl function ----------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "src/sys/epoll/epoll_ctl.h"
10 
11 #include "hdr/types/struct_epoll_event.h"
12 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
13 #include "src/__support/common.h"
14 #include "src/__support/macros/config.h"
15 #include "src/errno/libc_errno.h"
16 #include <sys/syscall.h> // For syscall numbers.
17 
18 namespace LIBC_NAMESPACE_DECL {
19 
20 LLVM_LIBC_FUNCTION(int, epoll_ctl,
21                    (int epfd, int op, int fd, epoll_event *event)) {
22   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_epoll_ctl, epfd, op, fd,
23                                               reinterpret_cast<long>(event));
24 
25   // A negative return value indicates an error with the magnitude of the
26   // value being the error code.
27   if (ret < 0) {
28     libc_errno = -ret;
29     return -1;
30   }
31 
32   return ret;
33 }
34 
35 } // namespace LIBC_NAMESPACE_DECL
36