Revert of Delete unused code httprequest, httpclient, and socketpool.

webrtc/base/socketpool.h

Index: webrtc/base/socketpool.h
diff --git a/webrtc/base/socketpool.h b/webrtc/base/socketpool.h
new file mode 100644
index 0000000000000000000000000000000000000000..5ceab203dc28c7c318a627e4ae6ef4b42bfc8aef
--- /dev/null
+++ b/webrtc/base/socketpool.h
@@ -0,0 +1,143 @@
+/*
+ *  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 WEBRTC_BASE_SOCKETPOOL_H_
+#define WEBRTC_BASE_SOCKETPOOL_H_
+
+#include <deque>
+#include <list>
+#include "webrtc/base/logging.h"
+#include "webrtc/base/sigslot.h"
+#include "webrtc/base/socketaddress.h"
+
+namespace rtc {
+
+class AsyncSocket;
+class LoggingAdapter;
+class SocketFactory;
+class SocketStream;
+class StreamInterface;
+
+//////////////////////////////////////////////////////////////////////
+// StreamPool
+//////////////////////////////////////////////////////////////////////
+
+class StreamPool {
+public:
+  virtual ~StreamPool() { }
+
+  virtual StreamInterface* RequestConnectedStream(const SocketAddress& remote,
+                                                  int* err) = 0;
+  virtual void ReturnConnectedStream(StreamInterface* stream) = 0;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// StreamCache - Caches a set of open streams, defers creation/destruction to
+//  the supplied StreamPool.
+///////////////////////////////////////////////////////////////////////////////
+
+class StreamCache : public StreamPool, public sigslot::has_slots<> {
+public:
+  StreamCache(StreamPool* pool);
+  ~StreamCache() override;
+
+  // StreamPool Interface
+  StreamInterface* RequestConnectedStream(const SocketAddress& remote,
+                                          int* err) override;
+  void ReturnConnectedStream(StreamInterface* stream) override;
+
+private:
+  typedef std::pair<SocketAddress, StreamInterface*> ConnectedStream;
+  typedef std::list<ConnectedStream> ConnectedList;
+
+  void OnStreamEvent(StreamInterface* stream, int events, int err);
+
+  // We delegate stream creation and deletion to this pool.
+  StreamPool* pool_;
+  // Streams that are in use (returned from RequestConnectedStream).
+  ConnectedList active_;
+  // Streams which were returned to us, but are still open.
+  ConnectedList cached_;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// NewSocketPool
+// Creates a new stream on every request
+///////////////////////////////////////////////////////////////////////////////
+
+class NewSocketPool : public StreamPool {
+public:
+  NewSocketPool(SocketFactory* factory);
+  ~NewSocketPool() override;
+  
+  // StreamPool Interface
+  StreamInterface* RequestConnectedStream(const SocketAddress& remote,
+                                          int* err) override;
+  void ReturnConnectedStream(StreamInterface* stream) override;
+
+private:
+  SocketFactory* factory_;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// ReuseSocketPool
+// Maintains a single socket at a time, and will reuse it without closing if
+// the destination address is the same.
+///////////////////////////////////////////////////////////////////////////////
+
+class ReuseSocketPool : public StreamPool, public sigslot::has_slots<> {
+public:
+  ReuseSocketPool(SocketFactory* factory);
+  ~ReuseSocketPool() override;
+
+  // StreamPool Interface
+  StreamInterface* RequestConnectedStream(const SocketAddress& remote,
+                                          int* err) override;
+  void ReturnConnectedStream(StreamInterface* stream) override;
+
+private:
+  void OnStreamEvent(StreamInterface* stream, int events, int err);
+
+  SocketFactory* factory_;
+  SocketStream* stream_;
+  SocketAddress remote_;
+  bool checked_out_;  // Whether the stream is currently checked out
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// LoggingPoolAdapter - Adapts a StreamPool to supply streams with attached
+// LoggingAdapters.
+///////////////////////////////////////////////////////////////////////////////
+
+class LoggingPoolAdapter : public StreamPool {
+public:
+  LoggingPoolAdapter(StreamPool* pool, LoggingSeverity level,
+                     const std::string& label, bool binary_mode);
+  ~LoggingPoolAdapter() override;
+
+  // StreamPool Interface
+  StreamInterface* RequestConnectedStream(const SocketAddress& remote,
+                                          int* err) override;
+  void ReturnConnectedStream(StreamInterface* stream) override;
+
+private:
+  StreamPool* pool_;
+  LoggingSeverity level_;
+  std::string label_;
+  bool binary_mode_;
+  typedef std::deque<LoggingAdapter*> StreamList;
+  StreamList recycle_bin_;
+};
+
+//////////////////////////////////////////////////////////////////////
+
+}  // namespace rtc
+
+#endif  // WEBRTC_BASE_SOCKETPOOL_H_