1 //
2 // Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2021
3 //
4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 #include "td/utils/port/detail/EventFdBsd.h"
8
9 char disable_linker_warning_about_empty_file_event_fd_bsd_cpp TD_UNUSED;
10
11 #ifdef TD_EVENTFD_BSD
12
13 #include "td/utils/logging.h"
14 #include "td/utils/port/detail/NativeFd.h"
15 #include "td/utils/port/detail/skip_eintr.h"
16 #include "td/utils/port/PollFlags.h"
17 #include "td/utils/port/SocketFd.h"
18 #include "td/utils/Slice.h"
19
20 #include <cerrno>
21
22 #include <fcntl.h>
23 #include <poll.h>
24 #include <sys/socket.h>
25 #include <sys/types.h>
26
27 namespace td {
28 namespace detail {
29
30 // TODO: it is extremely non optimal on Darwin. kqueue events should be used instead
init()31 void EventFdBsd::init() {
32 int fds[2];
33 int err = socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
34 auto socketpair_errno = errno;
35 #if TD_CYGWIN
36 // it looks like CYGWIN bug
37 int max_retries = 1000000;
38 while (err == -1 && socketpair_errno == EADDRINUSE && max_retries-- > 0) {
39 err = socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
40 socketpair_errno = errno;
41 }
42 // LOG_IF(ERROR, max_retries < 1000000) << max_retries;
43 #endif
44 LOG_IF(FATAL, err == -1) << Status::PosixError(socketpair_errno, "socketpair failed");
45
46 auto fd_a = NativeFd(fds[0]);
47 auto fd_b = NativeFd(fds[1]);
48 fd_a.set_is_blocking_unsafe(false).ensure();
49 fd_b.set_is_blocking_unsafe(false).ensure();
50
51 in_ = SocketFd::from_native_fd(std::move(fd_a)).move_as_ok();
52 out_ = SocketFd::from_native_fd(std::move(fd_b)).move_as_ok();
53 }
54
empty()55 bool EventFdBsd::empty() {
56 return in_.empty();
57 }
58
close()59 void EventFdBsd::close() {
60 in_.close();
61 out_.close();
62 }
63
get_pending_error()64 Status EventFdBsd::get_pending_error() {
65 return Status::OK();
66 }
67
get_poll_info()68 PollableFdInfo &EventFdBsd::get_poll_info() {
69 return out_.get_poll_info();
70 }
71
release()72 void EventFdBsd::release() {
73 int value = 1;
74 auto result = in_.write(Slice(reinterpret_cast<const char *>(&value), sizeof(value)));
75 if (result.is_error()) {
76 LOG(FATAL) << "EventFdBsd write failed: " << result.error();
77 }
78 size_t size = result.ok();
79 if (size != sizeof(value)) {
80 LOG(FATAL) << "EventFdBsd write returned " << size << " instead of " << sizeof(value);
81 }
82 }
83
acquire()84 void EventFdBsd::acquire() {
85 sync_with_poll(out_);
86 out_.get_poll_info().add_flags(PollFlags::Read());
87 while (can_read_local(out_)) {
88 uint8 value[1024];
89 auto result = out_.read(MutableSlice(value, sizeof(value)));
90 if (result.is_error()) {
91 LOG(FATAL) << "EventFdBsd read failed:" << result.error();
92 }
93 }
94 }
95
wait(int timeout_ms)96 void EventFdBsd::wait(int timeout_ms) {
97 detail::skip_eintr_timeout(
98 [this](int timeout_ms) {
99 pollfd fd;
100 fd.fd = get_poll_info().native_fd().fd();
101 fd.events = POLLIN;
102 return poll(&fd, 1, timeout_ms);
103 },
104 timeout_ms);
105 }
106
107 } // namespace detail
108 } // namespace td
109
110 #endif
111