commit d86c0cdbde7261deefc5771f41a14186bac9fd09
author Byoungchan Lee <daniel.l@hpcnt.com> Tue Apr 16 02:06:08 2024
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Apr 16 03:56:36 2024
tree 77626a7d70f2b00c8ccefbe032b7e247be51142d
parent e33313f80102d60a9303cb9a2fe4cecc50da5bc1

Extend use of poll() to Apple systems in addition to Linux and Fuchsia

To address the limitations of select(), poll() is now used for Apple
(MacOS and iOS) systems in the PhysicalSocketServer.

Bug: webrtc:15421, webrtc:15908
Change-Id: Ic6703a08653ca608a714ea37ecbbfeaf29743c1f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/316480
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Daniel.L (Byoungchan) Lee <daniel.l@hpcnt.com>
Cr-Commit-Position: refs/heads/main@{#42075}

rtc_base/physical_socket_server.cc

diff --git a/rtc_base/physical_socket_server.cc b/rtc_base/physical_socket_server.cc
index cd4f854..787e942 100644
--- a/rtc_base/physical_socket_server.cc
+++ b/rtc_base/physical_socket_server.cc
@@ -98,15 +98,15 @@
 typedef char* SockOptArg;
 #endif
 
-#if defined(WEBRTC_USE_EPOLL)
+#if defined(WEBRTC_LINUX)
 // POLLRDHUP / EPOLLRDHUP are only defined starting with Linux 2.6.17.
 #if !defined(POLLRDHUP)
 #define POLLRDHUP 0x2000
-#endif
+#endif  // !defined(POLLRDHUP)
 #if !defined(EPOLLRDHUP)
 #define EPOLLRDHUP 0x2000
-#endif
-#endif
+#endif  // !defined(EPOLLRDHUP)
+#endif  // defined(WEBRTC_LINUX)
 
 namespace {
 
@@ -1489,7 +1489,15 @@
 static void ProcessPollEvents(Dispatcher* dispatcher, const pollfd& pfd) {
   bool readable = (pfd.revents & (POLLIN | POLLPRI));
   bool writable = (pfd.revents & POLLOUT);
-  bool error = (pfd.revents & (POLLRDHUP | POLLERR | POLLHUP));
+
+  // Linux and Fuchsia define POLLRDHUP, which is set when the peer has
+  // disconnected. On other platforms, we only check for POLLHUP.
+#if defined(WEBRTC_LINUX) || defined(WEBRTC_FUCHSIA)
+  constexpr short kEvents = POLLRDHUP | POLLERR | POLLHUP;
+#else
+  constexpr short kEvents = POLLERR | POLLHUP;
+#endif
+  bool error = (pfd.revents & kEvents);
 
   ProcessEvents(dispatcher, readable, writable, error, error);
 }

rtc_base/physical_socket_server.h

diff --git a/rtc_base/physical_socket_server.h b/rtc_base/physical_socket_server.h
index ec30281..b8cf042 100644
--- a/rtc_base/physical_socket_server.h
+++ b/rtc_base/physical_socket_server.h
@@ -23,7 +23,7 @@
 #include <sys/epoll.h>
 
 #define WEBRTC_USE_EPOLL 1
-#elif defined(WEBRTC_FUCHSIA)
+#elif defined(WEBRTC_FUCHSIA) || defined(WEBRTC_MAC)
 // Fuchsia implements select and poll but not epoll, and testing shows that poll
 // is faster than select.
 #include <poll.h>
@@ -31,7 +31,7 @@
 #define WEBRTC_USE_POLL 1
 #else
 // On other POSIX systems, use select by default.
-#endif  // WEBRTC_LINUX, WEBRTC_FUCHSIA
+#endif  // WEBRTC_LINUX, WEBRTC_FUCHSIA, WEBRTC_MAC
 #endif  // WEBRTC_POSIX
 
 #include <array>
@@ -125,9 +125,6 @@
   const int epoll_fd_ = INVALID_SOCKET;
 
 #elif defined(WEBRTC_USE_POLL)
-  void AddPoll(Dispatcher* dispatcher, uint64_t key);
-  void RemovePoll(Dispatcher* dispatcher);
-  void UpdatePoll(Dispatcher* dispatcher, uint64_t key);
   bool WaitPoll(int cmsWait, bool process_io);
 
 #endif  // WEBRTC_USE_EPOLL, WEBRTC_USE_POLL