diff options
| -rw-r--r-- | src/libutil/monitor-fd.hh | 30 |
1 files changed, 23 insertions, 7 deletions
diff --git a/src/libutil/monitor-fd.hh b/src/libutil/monitor-fd.hh index e0ec66c01803..5ee0b88ef50f 100644 --- a/src/libutil/monitor-fd.hh +++ b/src/libutil/monitor-fd.hh @@ -21,13 +21,29 @@ public: MonitorFdHup(int fd) { thread = std::thread([fd]() { - /* Wait indefinitely until a POLLHUP occurs. */ - struct pollfd fds[1]; - fds[0].fd = fd; - fds[0].events = 0; - if (poll(fds, 1, -1) == -1) abort(); // can't happen - assert(fds[0].revents & POLLHUP); - triggerInterrupt(); + while (true) { + /* Wait indefinitely until a POLLHUP occurs. */ + struct pollfd fds[1]; + fds[0].fd = fd; + /* This shouldn't be necessary, but macOS doesn't seem to + like a zeroed out events field. + See rdar://37537852. + */ + fds[0].events = POLLHUP; + auto count = poll(fds, 1, -1); + if (count == -1) abort(); // can't happen + /* This shouldn't happen, but can on macOS due to a bug. + See rdar://37550628. + + This may eventually need a delay or further + coordination with the main thread if spinning proves + too harmful. + */ + if (count == 0) continue; + assert(fds[0].revents & POLLHUP); + triggerInterrupt(); + break; + } }); }; |