Adds a modified copy of talk/base to webrtc/base. It is the first step in migrating talk/base to webrtc/base.

BUG=N/A
R=andrew@webrtc.org, wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/12199004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6107 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/base/httpbase.h

@@ -0,0 +1,181 @@
+/*
+ *  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_HTTPBASE_H__
+#define WEBRTC_BASE_HTTPBASE_H__
+
+#include "webrtc/base/httpcommon.h"
+
+namespace rtc {
+
+class StreamInterface;
+
+///////////////////////////////////////////////////////////////////////////////
+// HttpParser - Parses an HTTP stream provided via Process and end_of_input, and
+// generates events for:
+//  Structural Elements: Leader, Headers, Document Data
+//  Events: End of Headers, End of Document, Errors
+///////////////////////////////////////////////////////////////////////////////
+
+class HttpParser {
+public:
+  enum ProcessResult { PR_CONTINUE, PR_BLOCK, PR_COMPLETE };
+  HttpParser();
+  virtual ~HttpParser();
+  
+  void reset();
+  ProcessResult Process(const char* buffer, size_t len, size_t* processed,
+                        HttpError* error);
+  bool is_valid_end_of_input() const;
+  void complete(HttpError err);
+  
+  size_t GetDataRemaining() const { return data_size_; }
+
+protected:
+  ProcessResult ProcessLine(const char* line, size_t len, HttpError* error);
+
+  // HttpParser Interface
+  virtual ProcessResult ProcessLeader(const char* line, size_t len,
+                                      HttpError* error) = 0;
+  virtual ProcessResult ProcessHeader(const char* name, size_t nlen,
+                                      const char* value, size_t vlen,
+                                      HttpError* error) = 0;
+  virtual ProcessResult ProcessHeaderComplete(bool chunked, size_t& data_size,
+                                              HttpError* error) = 0;
+  virtual ProcessResult ProcessData(const char* data, size_t len, size_t& read,
+                                    HttpError* error) = 0;
+  virtual void OnComplete(HttpError err) = 0;
+  
+private:
+  enum State {
+    ST_LEADER, ST_HEADERS,
+    ST_CHUNKSIZE, ST_CHUNKTERM, ST_TRAILERS,
+    ST_DATA, ST_COMPLETE
+  } state_;
+  bool chunked_;
+  size_t data_size_;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// IHttpNotify
+///////////////////////////////////////////////////////////////////////////////
+
+enum HttpMode { HM_NONE, HM_CONNECT, HM_RECV, HM_SEND };
+
+class IHttpNotify {
+public:
+  virtual ~IHttpNotify() {}
+  virtual HttpError onHttpHeaderComplete(bool chunked, size_t& data_size) = 0;
+  virtual void onHttpComplete(HttpMode mode, HttpError err) = 0;
+  virtual void onHttpClosed(HttpError err) = 0;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// HttpBase - Provides a state machine for implementing HTTP-based components.
+// Attach HttpBase to a StreamInterface which represents a bidirectional HTTP
+// stream, and then call send() or recv() to initiate sending or receiving one
+// side of an HTTP transaction.  By default, HttpBase operates as an I/O pump,
+// moving data from the HTTP stream to the HttpData object and vice versa.
+// However, it can also operate in stream mode, in which case the user of the
+// stream interface drives I/O via calls to Read().
+///////////////////////////////////////////////////////////////////////////////
+
+class HttpBase
+: private HttpParser,
+  public sigslot::has_slots<>
+{
+public:
+  HttpBase();
+  virtual ~HttpBase();
+
+  void notify(IHttpNotify* notify) { notify_ = notify; }
+  bool attach(StreamInterface* stream);
+  StreamInterface* stream() { return http_stream_; }
+  StreamInterface* detach();
+  bool isConnected() const;
+
+  void send(HttpData* data);
+  void recv(HttpData* data);
+  void abort(HttpError err);
+
+  HttpMode mode() const { return mode_; }
+
+  void set_ignore_data(bool ignore) { ignore_data_ = ignore; }
+  bool ignore_data() const { return ignore_data_; }
+
+  // Obtaining this stream puts HttpBase into stream mode until the stream
+  // is closed.  HttpBase can only expose one open stream interface at a time.
+  // Further calls will return NULL.
+  StreamInterface* GetDocumentStream();
+
+protected:
+  // Do cleanup when the http stream closes (error may be 0 for a clean
+  // shutdown), and return the error code to signal.
+  HttpError HandleStreamClose(int error);
+
+  // DoReceiveLoop acts as a data pump, pulling data from the http stream,
+  // pushing it through the HttpParser, and then populating the HttpData object
+  // based on the callbacks from the parser.  One of the most interesting
+  // callbacks is ProcessData, which provides the actual http document body.
+  // This data is then written to the HttpData::document.  As a result, data
+  // flows from the network to the document, with some incidental protocol
+  // parsing in between.
+  // Ideally, we would pass in the document* to DoReceiveLoop, to more easily
+  // support GetDocumentStream().  However, since the HttpParser is callback
+  // driven, we are forced to store the pointer somewhere until the callback
+  // is triggered.
+  // Returns true if the received document has finished, and
+  // HttpParser::complete should be called.
+  bool DoReceiveLoop(HttpError* err);
+
+  void read_and_process_data();
+  void flush_data();
+  bool queue_headers();
+  void do_complete(HttpError err = HE_NONE);
+
+  void OnHttpStreamEvent(StreamInterface* stream, int events, int error);
+  void OnDocumentEvent(StreamInterface* stream, int events, int error);
+
+  // HttpParser Interface
+  virtual ProcessResult ProcessLeader(const char* line, size_t len,
+                                      HttpError* error);
+  virtual ProcessResult ProcessHeader(const char* name, size_t nlen,
+                                      const char* value, size_t vlen,
+                                      HttpError* error);
+  virtual ProcessResult ProcessHeaderComplete(bool chunked, size_t& data_size,
+                                              HttpError* error);
+  virtual ProcessResult ProcessData(const char* data, size_t len, size_t& read,
+                                    HttpError* error);
+  virtual void OnComplete(HttpError err);
+
+private:
+  class DocumentStream;
+  friend class DocumentStream;
+
+  enum { kBufferSize = 32 * 1024 };
+
+  HttpMode mode_;
+  HttpData* data_;
+  IHttpNotify* notify_;
+  StreamInterface* http_stream_;
+  DocumentStream* doc_stream_;
+  char buffer_[kBufferSize];
+  size_t len_;
+
+  bool ignore_data_, chunk_data_;
+  HttpData::const_iterator header_;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+} // namespace rtc
+
+#endif // WEBRTC_BASE_HTTPBASE_H__