[Lldb-commits] [lldb] [lldb] Unify/improve MainLoop signal handling (PR #115197)

[Pavel Labath via lldb-commits]

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@@ -179,55 +142,34 @@ Status MainLoopPosix::RunImpl::Poll() {
     read_fds.push_back(pfd);
   }
 
-  if (ppoll(read_fds.data(), read_fds.size(), nullptr, &sigmask) == -1 &&
+  if (ppoll(read_fds.data(), read_fds.size(),
+            /*timeout=*/nullptr,
+            /*sigmask=*/nullptr) == -1 &&
       errno != EINTR)
     return Status(errno, eErrorTypePOSIX);
 
   return Status();
 }
-#endif
 
-void MainLoopPosix::RunImpl::ProcessEvents() {
-#ifdef __ANDROID__
-  // Collect first all readable file descriptors into a separate vector and
-  // then iterate over it to invoke callbacks. Iterating directly over
-  // loop.m_read_fds is not possible because the callbacks can modify the
-  // container which could invalidate the iterator.
-  std::vector<IOObject::WaitableHandle> fds;
-  for (const auto &fd : loop.m_read_fds)
-    if (FD_ISSET(fd.first, &read_fd_set))
-      fds.push_back(fd.first);
-
-  for (const auto &handle : fds) {
-#else
+void MainLoopPosix::RunImpl::ProcessReadEvents() {
   for (const auto &fd : read_fds) {
     if ((fd.revents & (POLLIN | POLLHUP)) == 0)
       continue;
     IOObject::WaitableHandle handle = fd.fd;
-#endif
     if (loop.m_terminate_request)
       return;
 
     loop.ProcessReadObject(handle);
   }
-
-  std::vector<int> signals;
-  for (const auto &entry : loop.m_signals)
-    if (g_signal_flags[entry.first] != 0)
-      signals.push_back(entry.first);
-
-  for (const auto &signal : signals) {
-    if (loop.m_terminate_request)
-      return;
-    g_signal_flags[signal] = 0;
-    loop.ProcessSignal(signal);
-  }
 }
 #endif
 
 MainLoopPosix::MainLoopPosix() : m_triggering(false) {
   Status error = m_trigger_pipe.CreateNew(/*child_process_inherit=*/false);
   assert(error.Success());
+  assert(fcntl(m_trigger_pipe.GetWriteFileDescriptor(), F_SETFL,
----------------
labath wrote:

I'm setting the *flags* on the descriptor. This is essentially `fd->flags |= O_NONBLOCK`. I added a comment and fixed the embarrassing mistake of putting a load-bearing statement into an assert block.

https://github.com/llvm/llvm-project/pull/115197