1 #include "private/uds/channel_event_set.h"
2
3 #include <log/log.h>
4
5 #include <uds/ipc_helper.h>
6
7 namespace android {
8 namespace pdx {
9 namespace uds {
10
ChannelEventSet()11 ChannelEventSet::ChannelEventSet() {
12 const int flags = EFD_CLOEXEC | EFD_NONBLOCK;
13 LocalHandle epoll_fd, event_fd;
14
15 if (!SetupHandle(epoll_create1(EPOLL_CLOEXEC), &epoll_fd, "epoll") ||
16 !SetupHandle(eventfd(0, flags), &event_fd, "event")) {
17 return;
18 }
19
20 epoll_event event;
21 event.events = 0;
22 event.data.u32 = 0;
23 if (epoll_ctl(epoll_fd.Get(), EPOLL_CTL_ADD, event_fd.Get(), &event) < 0) {
24 const int error = errno;
25 ALOGE("ChannelEventSet::ChannelEventSet: Failed to add event_fd: %s",
26 strerror(error));
27 return;
28 }
29
30 epoll_fd_ = std::move(epoll_fd);
31 event_fd_ = std::move(event_fd);
32 }
33
AddDataFd(const LocalHandle & data_fd)34 Status<void> ChannelEventSet::AddDataFd(const LocalHandle& data_fd) {
35 epoll_event event;
36 event.events = EPOLLHUP | EPOLLRDHUP;
37 event.data.u32 = event.events;
38 if (epoll_ctl(epoll_fd_.Get(), EPOLL_CTL_ADD, data_fd.Get(), &event) < 0) {
39 const int error = errno;
40 ALOGE("ChannelEventSet::ChannelEventSet: Failed to add event_fd: %s",
41 strerror(error));
42 return ErrorStatus{error};
43 } else {
44 return {};
45 }
46 }
47
ModifyEvents(int clear_mask,int set_mask)48 int ChannelEventSet::ModifyEvents(int clear_mask, int set_mask) {
49 ALOGD_IF(TRACE, "ChannelEventSet::ModifyEvents: clear_mask=%x set_mask=%x",
50 clear_mask, set_mask);
51 const int old_bits = event_bits_;
52 const int new_bits = (event_bits_ & ~clear_mask) | set_mask;
53 event_bits_ = new_bits;
54
55 // If anything changed clear the event and update the event mask.
56 if (old_bits != new_bits) {
57 eventfd_t value;
58 eventfd_read(event_fd_.Get(), &value);
59
60 epoll_event event;
61 event.events = POLLIN;
62 event.data.u32 = event_bits_;
63 if (epoll_ctl(epoll_fd_.Get(), EPOLL_CTL_MOD, event_fd_.Get(), &event) <
64 0) {
65 const int error = errno;
66 ALOGE("ChannelEventSet::AddEventHandle: Failed to update event: %s",
67 strerror(error));
68 return -error;
69 }
70 }
71
72 // If there are any bits set, re-trigger the eventfd.
73 if (new_bits)
74 eventfd_write(event_fd_.Get(), 1);
75
76 return 0;
77 }
78
SetupHandle(int fd,LocalHandle * handle,const char * error_name)79 Status<void> ChannelEventSet::SetupHandle(int fd, LocalHandle* handle,
80 const char* error_name) {
81 const int error = errno;
82 handle->Reset(fd);
83 if (!*handle) {
84 ALOGE("ChannelEventSet::SetupHandle: Failed to setup %s handle: %s",
85 error_name, strerror(error));
86 return ErrorStatus{error};
87 }
88 return {};
89 }
90
GetPendingEvents() const91 Status<int> ChannelEventReceiver::GetPendingEvents() const {
92 constexpr long kTimeoutMs = 0;
93 epoll_event event;
94 const int count =
95 RETRY_EINTR(epoll_wait(epoll_fd_.Get(), &event, 1, kTimeoutMs));
96
97 Status<int> status;
98 if (count < 0) {
99 status.SetError(errno);
100 ALOGE("ChannelEventReceiver::GetPendingEvents: Failed to get events: %s",
101 status.GetErrorMessage().c_str());
102 return status;
103 }
104
105 const int mask_out = event.data.u32;
106 ALOGD_IF(TRACE, "ChannelEventReceiver::GetPendingEvents: mask_out=%x",
107 mask_out);
108
109 status.SetValue(mask_out);
110 return status;
111 }
112
113 } // namespace uds
114 } // namespace pdx
115 } // namespace android
116