1 files changed, 279 insertions, 0 deletions
diff --git a/third_party/libwebrtc/rtc_base/physical_socket_server.h b/third_party/libwebrtc/rtc_base/physical_socket_server.h
new file mode 100644
index 0000000000..5a3acbf84f
--- /dev/null
+++ b/third_party/libwebrtc/rtc_base/physical_socket_server.h
@@ -0,0 +1,279 @@
+/*
+ *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef RTC_BASE_PHYSICAL_SOCKET_SERVER_H_
+#define RTC_BASE_PHYSICAL_SOCKET_SERVER_H_
+
+#include "api/units/time_delta.h"
+#if defined(WEBRTC_POSIX) && defined(WEBRTC_LINUX)
+#include <sys/epoll.h>
+#define WEBRTC_USE_EPOLL 1
+#endif
+
+#include <array>
+#include <memory>
+#include <unordered_map>
+#include <vector>
+
+#include "rtc_base/async_resolver.h"
+#include "rtc_base/async_resolver_interface.h"
+#include "rtc_base/deprecated/recursive_critical_section.h"
+#include "rtc_base/socket_server.h"
+#include "rtc_base/synchronization/mutex.h"
+#include "rtc_base/system/rtc_export.h"
+#include "rtc_base/thread_annotations.h"
+
+#if defined(WEBRTC_POSIX)
+typedef int SOCKET;
+#endif  // WEBRTC_POSIX
+
+namespace rtc {
+
+// Event constants for the Dispatcher class.
+enum DispatcherEvent {
+  DE_READ = 0x0001,
+  DE_WRITE = 0x0002,
+  DE_CONNECT = 0x0004,
+  DE_CLOSE = 0x0008,
+  DE_ACCEPT = 0x0010,
+};
+
+class Signaler;
+
+class Dispatcher {
+ public:
+  virtual ~Dispatcher() {}
+  virtual uint32_t GetRequestedEvents() = 0;
+  virtual void OnEvent(uint32_t ff, int err) = 0;
+#if defined(WEBRTC_WIN)
+  virtual WSAEVENT GetWSAEvent() = 0;
+  virtual SOCKET GetSocket() = 0;
+  virtual bool CheckSignalClose() = 0;
+#elif defined(WEBRTC_POSIX)
+  virtual int GetDescriptor() = 0;
+  virtual bool IsDescriptorClosed() = 0;
+#endif
+};
+
+// A socket server that provides the real sockets of the underlying OS.
+class RTC_EXPORT PhysicalSocketServer : public SocketServer {
+ public:
+  PhysicalSocketServer();
+  ~PhysicalSocketServer() override;
+
+  // SocketFactory:
+  Socket* CreateSocket(int family, int type) override;
+
+  // Internal Factory for Accept (virtual so it can be overwritten in tests).
+  virtual Socket* WrapSocket(SOCKET s);
+
+  // SocketServer:
+  bool Wait(webrtc::TimeDelta max_wait_duration, bool process_io) override;
+  void WakeUp() override;
+
+  void Add(Dispatcher* dispatcher);
+  void Remove(Dispatcher* dispatcher);
+  void Update(Dispatcher* dispatcher);
+
+ private:
+  // The number of events to process with one call to "epoll_wait".
+  static constexpr size_t kNumEpollEvents = 128;
+  // A local historical definition of "foreverness", in milliseconds.
+  static constexpr int kForeverMs = -1;
+
+  static int ToCmsWait(webrtc::TimeDelta max_wait_duration);
+#if defined(WEBRTC_POSIX)
+  bool WaitSelect(int cmsWait, bool process_io);
+#endif  // WEBRTC_POSIX
+#if defined(WEBRTC_USE_EPOLL)
+  void AddEpoll(Dispatcher* dispatcher, uint64_t key);
+  void RemoveEpoll(Dispatcher* dispatcher);
+  void UpdateEpoll(Dispatcher* dispatcher, uint64_t key);
+  bool WaitEpoll(int cmsWait);
+  bool WaitPoll(int cmsWait, Dispatcher* dispatcher);
+
+  // This array is accessed in isolation by a thread calling into Wait().
+  // It's useless to use a SequenceChecker to guard it because a socket
+  // server can outlive the thread it's bound to, forcing the Wait call
+  // to have to reset the sequence checker on Wait calls.
+  std::array<epoll_event, kNumEpollEvents> epoll_events_;
+  const int epoll_fd_ = INVALID_SOCKET;
+#endif  // WEBRTC_USE_EPOLL
+  // uint64_t keys are used to uniquely identify a dispatcher in order to avoid
+  // the ABA problem during the epoll loop (a dispatcher being destroyed and
+  // replaced by one with the same address).
+  uint64_t next_dispatcher_key_ RTC_GUARDED_BY(crit_) = 0;
+  std::unordered_map<uint64_t, Dispatcher*> dispatcher_by_key_
+      RTC_GUARDED_BY(crit_);
+  // Reverse lookup necessary for removals/updates.
+  std::unordered_map<Dispatcher*, uint64_t> key_by_dispatcher_
+      RTC_GUARDED_BY(crit_);
+  // A list of dispatcher keys that we're interested in for the current
+  // select() or WSAWaitForMultipleEvents() loop. Again, used to avoid the ABA
+  // problem (a socket being destroyed and a new one created with the same
+  // handle, erroneously receiving the events from the destroyed socket).
+  //
+  // Kept as a member variable just for efficiency.
+  std::vector<uint64_t> current_dispatcher_keys_;
+  Signaler* signal_wakeup_;  // Assigned in constructor only
+  RecursiveCriticalSection crit_;
+#if defined(WEBRTC_WIN)
+  const WSAEVENT socket_ev_;
+#endif
+  bool fWait_;
+  // Are we currently in a select()/epoll()/WSAWaitForMultipleEvents loop?
+  // Used for a DCHECK, because we don't support reentrant waiting.
+  bool waiting_ = false;
+};
+
+class PhysicalSocket : public Socket, public sigslot::has_slots<> {
+ public:
+  PhysicalSocket(PhysicalSocketServer* ss, SOCKET s = INVALID_SOCKET);
+  ~PhysicalSocket() override;
+
+  // Creates the underlying OS socket (same as the "socket" function).
+  virtual bool Create(int family, int type);
+
+  SocketAddress GetLocalAddress() const override;
+  SocketAddress GetRemoteAddress() const override;
+
+  int Bind(const SocketAddress& bind_addr) override;
+  int Connect(const SocketAddress& addr) override;
+
+  int GetError() const override;
+  void SetError(int error) override;
+
+  ConnState GetState() const override;
+
+  int GetOption(Option opt, int* value) override;
+  int SetOption(Option opt, int value) override;
+
+  int Send(const void* pv, size_t cb) override;
+  int SendTo(const void* buffer,
+             size_t length,
+             const SocketAddress& addr) override;
+
+  int Recv(void* buffer, size_t length, int64_t* timestamp) override;
+  int RecvFrom(void* buffer,
+               size_t length,
+               SocketAddress* out_addr,
+               int64_t* timestamp) override;
+
+  int Listen(int backlog) override;
+  Socket* Accept(SocketAddress* out_addr) override;
+
+  int Close() override;
+
+  SocketServer* socketserver() { return ss_; }
+
+ protected:
+  int DoConnect(const SocketAddress& connect_addr);
+
+  // Make virtual so ::accept can be overwritten in tests.
+  virtual SOCKET DoAccept(SOCKET socket, sockaddr* addr, socklen_t* addrlen);
+
+  // Make virtual so ::send can be overwritten in tests.
+  virtual int DoSend(SOCKET socket, const char* buf, int len, int flags);
+
+  // Make virtual so ::sendto can be overwritten in tests.
+  virtual int DoSendTo(SOCKET socket,
+                       const char* buf,
+                       int len,
+                       int flags,
+                       const struct sockaddr* dest_addr,
+                       socklen_t addrlen);
+
+  int DoReadFromSocket(void* buffer,
+                       size_t length,
+                       SocketAddress* out_addr,
+                       int64_t* timestamp);
+
+  void OnResolveResult(AsyncResolverInterface* resolver);
+
+  void UpdateLastError();
+  void MaybeRemapSendError();
+
+  uint8_t enabled_events() const { return enabled_events_; }
+  virtual void SetEnabledEvents(uint8_t events);
+  virtual void EnableEvents(uint8_t events);
+  virtual void DisableEvents(uint8_t events);
+
+  int TranslateOption(Option opt, int* slevel, int* sopt);
+
+  PhysicalSocketServer* ss_;
+  SOCKET s_;
+  bool udp_;
+  int family_ = 0;
+  mutable webrtc::Mutex mutex_;
+  int error_ RTC_GUARDED_BY(mutex_);
+  ConnState state_;
+  AsyncResolver* resolver_;
+
+#if !defined(NDEBUG)
+  std::string dbg_addr_;
+#endif
+
+ private:
+  const bool read_scm_timestamp_experiment_;
+  uint8_t enabled_events_ = 0;
+};
+
+class SocketDispatcher : public Dispatcher, public PhysicalSocket {
+ public:
+  explicit SocketDispatcher(PhysicalSocketServer* ss);
+  SocketDispatcher(SOCKET s, PhysicalSocketServer* ss);
+  ~SocketDispatcher() override;
+
+  bool Initialize();
+
+  virtual bool Create(int type);
+  bool Create(int family, int type) override;
+
+#if defined(WEBRTC_WIN)
+  WSAEVENT GetWSAEvent() override;
+  SOCKET GetSocket() override;
+  bool CheckSignalClose() override;
+#elif defined(WEBRTC_POSIX)
+  int GetDescriptor() override;
+  bool IsDescriptorClosed() override;
+#endif
+
+  uint32_t GetRequestedEvents() override;
+  void OnEvent(uint32_t ff, int err) override;
+
+  int Close() override;
+
+#if defined(WEBRTC_USE_EPOLL)
+ protected:
+  void StartBatchedEventUpdates();
+  void FinishBatchedEventUpdates();
+
+  void SetEnabledEvents(uint8_t events) override;
+  void EnableEvents(uint8_t events) override;
+  void DisableEvents(uint8_t events) override;
+#endif
+
+ private:
+#if defined(WEBRTC_WIN)
+  static int next_id_;
+  int id_;
+  bool signal_close_;
+  int signal_err_;
+#endif  // WEBRTC_WIN
+#if defined(WEBRTC_USE_EPOLL)
+  void MaybeUpdateDispatcher(uint8_t old_events);
+
+  int saved_enabled_events_ = -1;
+#endif
+};
+
+}  // namespace rtc
+
+#endif  // RTC_BASE_PHYSICAL_SOCKET_SERVER_H_