Refactor the HTTP parser to collect headers

sdk/lib/io/http_impl.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-class _HttpHeaders implements HttpHeaders {
-  _HttpHeaders() : _headers = new Map<String, List<String>>();
-
-  List<String> operator[](String name) {
-    name = name.toLowerCase();
-    return _headers[name];
-  }
-
-  String value(String name) {
-    name = name.toLowerCase();
-    List<String> values = _headers[name];
-    if (values == null) return null;
-    if (values.length > 1) {
-      throw new HttpException("More than one value for header $name");
-    }
-    return values[0];
-  }
-
-  void add(String name, Object value) {
-    _checkMutable();
-    if (value is List) {
-      for (int i = 0; i < value.length; i++) {
-        _add(name, value[i]);
-      }
-    } else {
-      _add(name, value);
-    }
-  }
-
-  void set(String name, Object value) {
-    name = name.toLowerCase();
-    _checkMutable();
-    removeAll(name);
-    add(name, value);
-  }
-
-  void remove(String name, Object value) {
-    _checkMutable();
-    name = name.toLowerCase();
-    List<String> values = _headers[name];
-    if (values != null) {
-      int index = values.indexOf(value);
-      if (index != -1) {
-        values.removeRange(index, 1);
-      }
-    }
-  }
-
-  void removeAll(String name) {
-    _checkMutable();
-    name = name.toLowerCase();
-    _headers.remove(name);
-  }
-
-  void forEach(void f(String name, List<String> values)) {
-    _headers.forEach(f);
-  }
-
-  void noFolding(String name) {
-    if (_noFoldingHeaders == null) _noFoldingHeaders = new List<String>();
-    _noFoldingHeaders.add(name);
-  }
-
-  String get host => _host;
-
-  void set host(String host) {
-    _checkMutable();
-    _host = host;
-    _updateHostHeader();
-  }
-
-  int get port => _port;
-
-  void set port(int port) {
-    _checkMutable();
-    _port = port;
-    _updateHostHeader();
-  }
-
-  Date get ifModifiedSince {
-    List<String> values = _headers["if-modified-since"];
-    if (values != null) {
-      try {
-        return _HttpUtils.parseDate(values[0]);
-      } on Exception catch (e) {
-        return null;
-      }
-    }
-    return null;
-  }
-
-  void set ifModifiedSince(Date ifModifiedSince) {
-    _checkMutable();
-    // Format "ifModifiedSince" header with date in Greenwich Mean Time (GMT).
-    String formatted = _HttpUtils.formatDate(ifModifiedSince.toUtc());
-    _set("if-modified-since", formatted);
-  }
-
-  Date get date {
-    List<String> values = _headers["date"];
-    if (values != null) {
-      try {
-        return _HttpUtils.parseDate(values[0]);
-      } on Exception catch (e) {
-        return null;
-      }
-    }
-    return null;
-  }
-
-  void set date(Date date) {
-    _checkMutable();
-    // Format "Date" header with date in Greenwich Mean Time (GMT).
-    String formatted = _HttpUtils.formatDate(date.toUtc());
-    _set("date", formatted);
-  }
-
-  Date get expires {
-    List<String> values = _headers["expires"];
-    if (values != null) {
-      try {
-        return _HttpUtils.parseDate(values[0]);
-      } on Exception catch (e) {
-        return null;
-      }
-    }
-    return null;
-  }
-
-  void set expires(Date expires) {
-    _checkMutable();
-    // Format "Expires" header with date in Greenwich Mean Time (GMT).
-    String formatted = _HttpUtils.formatDate(expires.toUtc());
-    _set("expires", formatted);
-  }
-
-  ContentType get contentType {
-    var values = _headers["content-type"];
-    if (values != null) {
-      return new ContentType.fromString(values[0]);
-    } else {
-      return new ContentType();
-    }
-  }
-
-  void set contentType(ContentType contentType) {
-    _checkMutable();
-    _set("content-type", contentType.toString());
-  }
-
-  void _add(String name, Object value) {
-    var lowerCaseName = name.toLowerCase();
-    // TODO(sgjesse): Add immutable state throw HttpException is immutable.
-    if (lowerCaseName == "date") {
-      if (value is Date) {
-        date = value;
-      } else if (value is String) {
-        _set("date", value);
-      } else {
-        throw new HttpException("Unexpected type for header named $name");
-      }
-    } else if (lowerCaseName == "expires") {
-      if (value is Date) {
-        expires = value;
-      } else if (value is String) {
-        _set("expires", value);
-      } else {
-        throw new HttpException("Unexpected type for header named $name");
-      }
-    } else if (lowerCaseName == "if-modified-since") {
-      if (value is Date) {
-        ifModifiedSince = value;
-      } else if (value is String) {
-        _set("if-modified-since", value);
-      } else {
-        throw new HttpException("Unexpected type for header named $name");
-      }
-    } else if (lowerCaseName == "host") {
-      int pos = value.indexOf(":");
-      if (pos == -1) {
-        _host = value;
-        _port = HttpClient.DEFAULT_HTTP_PORT;
-      } else {
-        if (pos > 0) {
-          _host = value.substring(0, pos);
-        } else {
-          _host = null;
-        }
-        if (pos + 1 == value.length) {
-          _port = HttpClient.DEFAULT_HTTP_PORT;
-        } else {
-          try {
-            _port = parseInt(value.substring(pos + 1));
-          } on FormatException catch (e) {
-            _port = null;
-          }
-        }
-        _set("host", value);
-      }
-    } else if (lowerCaseName == "content-type") {
-      _set("content-type", value);
-    } else {
-      name = lowerCaseName;
-      List<String> values = _headers[name];
-      if (values == null) {
-        values = new List<String>();
-        _headers[name] = values;
-      }
-      if (value is Date) {
-        values.add(_HttpUtils.formatDate(value));
-      } else {
-        values.add(value.toString());
-      }
-    }
-  }
-
-  void _set(String name, String value) {
-    name = name.toLowerCase();
-    List<String> values = new List<String>();
-    _headers[name] = values;
-    values.add(value);
-  }
-
-  _checkMutable() {
-    if (!_mutable) throw new HttpException("HTTP headers are not mutable");
-  }
-
-  _updateHostHeader() {
-    bool defaultPort = _port == null || _port == HttpClient.DEFAULT_HTTP_PORT;
-    String portPart = defaultPort ? "" : ":$_port";
-    _set("host", "$host$portPart");
-  }
-
-  _foldHeader(String name) {
-    if (name == "set-cookie" ||
-        (_noFoldingHeaders != null &&
-         _noFoldingHeaders.indexOf(name) != -1)) {
-      return false;
-    }
-    return true;
-  }
-
-  _write(_HttpConnectionBase connection) {
-    final COLONSP = const [_CharCode.COLON, _CharCode.SP];
-    final COMMASP = const [_CharCode.COMMA, _CharCode.SP];
-    final CRLF = const [_CharCode.CR, _CharCode.LF];
-
-    var bufferSize = 16 * 1024;
-    var buffer = new Uint8List(bufferSize);
-    var bufferPos = 0;
-
-    void writeBuffer() {
-      connection._writeFrom(buffer, 0, bufferPos);
-      bufferPos = 0;
-    }
-
-    // Format headers.
-    _headers.forEach((String name, List<String> values) {
-      bool fold = _foldHeader(name);
-      List<int> nameData;
-      nameData = name.charCodes;
-      int nameDataLen = nameData.length;
-      if (nameDataLen + 2 > bufferSize - bufferPos) writeBuffer();
-      buffer.setRange(bufferPos, nameDataLen, nameData);
-      bufferPos += nameDataLen;
-      buffer[bufferPos++] = _CharCode.COLON;
-      buffer[bufferPos++] = _CharCode.SP;
-      for (int i = 0; i < values.length; i++) {
-        List<int> data = values[i].charCodes;
-        int dataLen = data.length;
-        // Worst case here is writing the name, value and 6 additional bytes.
-        if (nameDataLen + dataLen + 6 > bufferSize - bufferPos) writeBuffer();
-        if (i > 0) {
-          if (fold) {
-            buffer[bufferPos++] = _CharCode.COMMA;
-            buffer[bufferPos++] = _CharCode.SP;
-          } else {
-            buffer[bufferPos++] = _CharCode.CR;
-            buffer[bufferPos++] = _CharCode.LF;
-            buffer.setRange(bufferPos, nameDataLen, nameData);
-            bufferPos += nameDataLen;
-            buffer[bufferPos++] = _CharCode.COLON;
-            buffer[bufferPos++] = _CharCode.SP;
-          }
-        }
-        buffer.setRange(bufferPos, dataLen, data);
-        bufferPos += dataLen;
-      }
-      buffer[bufferPos++] = _CharCode.CR;
-      buffer[bufferPos++] = _CharCode.LF;
-    });
-    writeBuffer();
-  }
-
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    _headers.forEach((String name, List<String> values) {
-      sb.add(name);
-      sb.add(": ");
-      bool fold = _foldHeader(name);
-      for (int i = 0; i < values.length; i++) {
-        if (i > 0) {
-          if (fold) {
-            sb.add(", ");
-          } else {
-            sb.add("\n");
-            sb.add(name);
-            sb.add(": ");
-          }
-        }
-        sb.add(values[i]);
-      }
-      sb.add("\n");
-    });
-    return sb.toString();
-  }
-
-  bool _mutable = true;  // Are the headers currently mutable?
-  Map<String, List<String>> _headers;
-  List<String> _noFoldingHeaders;
-
-  String _host;
-  int _port;
-}
-
-
-class _HeaderValue implements HeaderValue {
-  _HeaderValue([String this.value = ""]);
-
-  _HeaderValue.fromString(String value, {this.parameterSeparator: ";"}) {
-    // Parse the string.
-    _parse(value);
-  }
-
-  Map<String, String> get parameters {
-    if (_parameters == null) _parameters = new Map<String, String>();
-    return _parameters;
-  }
-
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    sb.add(value);
-    if (parameters != null && parameters.length > 0) {
-      _parameters.forEach((String name, String value) {
-        sb.add("; ");
-        sb.add(name);
-        sb.add("=");
-        sb.add(value);
-      });
-    }
-    return sb.toString();
-  }
-
-  void _parse(String s) {
-    int index = 0;
-
-    bool done() => index == s.length;
-
-    void skipWS() {
-      while (!done()) {
-        if (s[index] != " " && s[index] != "\t") return;
-        index++;
-      }
-    }
-
-    String parseValue() {
-      int start = index;
-      while (!done()) {
-        if (s[index] == " " ||
-            s[index] == "\t" ||
-            s[index] == parameterSeparator) break;
-        index++;
-      }
-      return s.substring(start, index).toLowerCase();
-    }
-
-    void expect(String expected) {
-      if (done() || s[index] != expected) {
-        throw new HttpException("Failed to parse header value");
-      }
-      index++;
-    }
-
-    void maybeExpect(String expected) {
-      if (s[index] == expected) index++;
-    }
-
-    void parseParameters() {
-      _parameters = new Map<String, String>();
-
-      String parseParameterName() {
-        int start = index;
-        while (!done()) {
-          if (s[index] == " " || s[index] == "\t" || s[index] == "=") break;
-          index++;
-        }
-        return s.substring(start, index).toLowerCase();
-      }
-
-      String parseParameterValue() {
-        if (s[index] == "\"") {
-          // Parse quoted value.
-          StringBuffer sb = new StringBuffer();
-          index++;
-          while (!done()) {
-            if (s[index] == "\\") {
-              if (index + 1 == s.length) {
-                throw new HttpException("Failed to parse header value");
-              }
-              index++;
-            } else if (s[index] == "\"") {
-              index++;
-              break;
-            }
-            sb.add(s[index]);
-            index++;
-          }
-          return sb.toString();
-        } else {
-          // Parse non-quoted value.
-          return parseValue();
-        }
-      }
-
-      while (!done()) {
-        skipWS();
-        if (done()) return;
-        String name = parseParameterName();
-        skipWS();
-        expect("=");
-        skipWS();
-        String value = parseParameterValue();
-        _parameters[name] = value;
-        skipWS();
-        if (done()) return;
-        expect(parameterSeparator);
-      }
-    }
-
-    skipWS();
-    value = parseValue();
-    skipWS();
-    if (done()) return;
-    maybeExpect(parameterSeparator);
-    parseParameters();
-  }
-
-  String value;
-  String parameterSeparator;
-  Map<String, String> _parameters;
-}
-
-
-class _ContentType extends _HeaderValue implements ContentType {
-  _ContentType(String primaryType, String subType)
-      : _primaryType = primaryType, _subType = subType, super("");
-
-  _ContentType.fromString(String value) : super.fromString(value);
-
-  String get value => "$_primaryType/$_subType";
-
-  void set value(String s) {
-    int index = s.indexOf("/");
-    if (index == -1 || index == (s.length - 1)) {
-      primaryType = s.trim().toLowerCase();
-      subType = "";
-    } else {
-      primaryType = s.substring(0, index).trim().toLowerCase();
-      subType = s.substring(index + 1).trim().toLowerCase();
-    }
-  }
-
-  String get primaryType => _primaryType;
-
-  void set primaryType(String s) {
-    _primaryType = s;
-  }
-
-  String get subType => _subType;
-
-  void set subType(String s) {
-    _subType = s;
-  }
-
-  String get charset => parameters["charset"];
-
-  void set charset(String s) {
-    parameters["charset"] = s;
-  }
-
-  String _primaryType = "";
-  String _subType = "";
-}
-
-
-class _Cookie implements Cookie {
-  _Cookie([String this.name, String this.value]);
-
-  _Cookie.fromSetCookieValue(String value) {
-    // Parse the Set-Cookie header value.
-    _parseSetCookieValue(value);
-  }
-
-  // Parse a Set-Cookie header value according to the rules in RFC 6265.
-  void _parseSetCookieValue(String s) {
-    int index = 0;
-
-    bool done() => index == s.length;
-
-    String parseName() {
-      int start = index;
-      while (!done()) {
-        if (s[index] == "=") break;
-        index++;
-      }
-      return s.substring(start, index).trim().toLowerCase();
-    }
-
-    String parseValue() {
-      int start = index;
-      while (!done()) {
-        if (s[index] == ";") break;
-        index++;
-      }
-      return s.substring(start, index).trim().toLowerCase();
-    }
-
-    void expect(String expected) {
-      if (done()) throw new HttpException("Failed to parse header value [$s]");
-      if (s[index] != expected) {
-        throw new HttpException("Failed to parse header value [$s]");
-      }
-      index++;
-    }
-
-    void parseAttributes() {
-      String parseAttributeName() {
-        int start = index;
-        while (!done()) {
-          if (s[index] == "=" || s[index] == ";") break;
-          index++;
-        }
-        return s.substring(start, index).trim().toLowerCase();
-      }
-
-      String parseAttributeValue() {
-        int start = index;
-        while (!done()) {
-          if (s[index] == ";") break;
-          index++;
-        }
-        return s.substring(start, index).trim().toLowerCase();
-      }
-
-      while (!done()) {
-        String name = parseAttributeName();
-        String value = "";
-        if (!done() && s[index] == "=") {
-          index++;  // Skip the = character.
-          value = parseAttributeValue();
-        }
-        if (name == "expires") {
-          expires = _HttpUtils.parseCookieDate(value);
-        } else if (name == "max-age") {
-          maxAge = parseInt(value);
-        } else if (name == "domain") {
-          domain = value;
-        } else if (name == "path") {
-          path = value;
-        } else if (name == "httponly") {
-          httpOnly = true;
-        } else if (name == "secure") {
-          secure = true;
-        }
-        if (!done()) index++;  // Skip the ; character
-      }
-    }
-
-    name = parseName();
-    if (done() || name.length == 0) {
-      throw new HttpException("Failed to parse header value [$s]");
-    }
-    index++;  // Skip the = character.
-    value = parseValue();
-    if (done()) return;
-    index++;  // Skip the ; character.
-    parseAttributes();
-  }
-
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    sb.add(name);
-    sb.add("=");
-    sb.add(value);
-    if (expires != null) {
-      sb.add("; Expires=");
-      sb.add(_HttpUtils.formatDate(expires));
-    }
-    if (maxAge != null) {
-      sb.add("; Max-Age=");
-      sb.add(maxAge);
-    }
-    if (domain != null) {
-      sb.add("; Domain=");
-      sb.add(domain);
-    }
-    if (path != null) {
-      sb.add("; Path=");
-      sb.add(path);
-    }
-    if (secure) sb.add("; Secure");
-    if (httpOnly) sb.add("; HttpOnly");
-    return sb.toString();
-  }
-
-  String name;
-  String value;
-  Date expires;
-  int maxAge;
-  String domain;
-  String path;
-  bool httpOnly = false;
-  bool secure = false;
-}
-
-
 // The close queue handles graceful closing of HTTP connections. When
 // a connection is added to the queue it will enter a wait state
 // waiting for all data written and possibly socket shutdown from
 // peer.
 class _CloseQueue {
   _CloseQueue() : _q = new Set<_HttpConnectionBase>();
 
   void add(_HttpConnectionBase connection) {
     void closeIfDone() {
       // We only check for write closed here. This means that we are
@@ skipping 53 matching lines @@
     _q.forEach((_HttpConnectionBase connection) {
       connection._socket.close();
     });
   }
 
   final Set<_HttpConnectionBase> _q;
 }
 
 
 class _HttpRequestResponseBase {
-  final int START = 0;
-  final int HEADER_SENT = 1;
-  final int DONE = 2;
-  final int UPGRADED = 3;
+  static const int START = 0;
+  static const int HEADER_SENT = 1;
+  static const int DONE = 2;
+  static const int UPGRADED = 3;
 
   _HttpRequestResponseBase(_HttpConnectionBase this._httpConnection)
-      : _headers = new _HttpHeaders() {
-    _state = START;
-    _headResponse = false;
-  }
+      : _state = START, _headResponse = false;
 
   int get contentLength => _contentLength;
   HttpHeaders get headers => _headers;
 
   bool get persistentConnection {
     List<String> connection = headers[HttpHeaders.CONNECTION];
     if (_protocolVersion == "1.1") {
       if (connection == null) return true;
       return !headers[HttpHeaders.CONNECTION].some(
           (value) => value.toLowerCase() == "close");
@@ skipping 227 matching lines @@
   HttpSession session([init(HttpSession session)]) {
     if (_session != null) {
       // It's already mapped, use it.
       return _session;
     }
     // Create session, store it in connection, and return.
     var sessionManager = _httpConnection._server._sessionManager;
     return _session = sessionManager.createSession(init);
   }
 
-  void _onRequestStart(String method, String uri, String version) {
+  void _onRequestReceived(String method,
+                          String uri,
+                          String version,
+                          _HttpHeaders headers) {
     _method = method;
     _uri = uri;
     _parseRequestUri(uri);
-  }
-
-  void _onHeaderReceived(String name, String value) {
-    _headers.add(name, value);
-  }
-
-  void _onHeadersComplete() {
+    _headers = headers;
     if (_httpConnection._server._sessionManagerInstance != null) {
       // Map to session if exists.
       var sessionId = cookies.reduce(null, (last, cookie) {
         if (last != null) return last;
         return cookie.name.toUpperCase() == _DART_SESSION_ID ?
             cookie.value : null;
       });
       if (sessionId != null) {
         var sessionManager = _httpConnection._server._sessionManager;
         _session = sessionManager.getSession(sessionId);
@@ skipping 66 matching lines @@
   _BufferList _buffer;
   Function _streamErrorHandler;
   _HttpSession _session;
 }
 
 
 // HTTP response object for sending a HTTP response.
 class _HttpResponse extends _HttpRequestResponseBase implements HttpResponse {
   _HttpResponse(_HttpConnection httpConnection)
       : super(httpConnection),
-        _statusCode = HttpStatus.OK;
+        _statusCode = HttpStatus.OK {
+    _headers = new _HttpHeaders();
+  }
 
   void set contentLength(int contentLength) {
-    if (_state >= HEADER_SENT) throw new HttpException("Header already sent");
+    if (_state >= _HttpRequestResponseBase.HEADER_SENT) {
+      throw new HttpException("Header already sent");
+    }
     _contentLength = contentLength;
   }
 
   int get statusCode => _statusCode;
   void set statusCode(int statusCode) {
     if (_outputStream != null) throw new HttpException("Header already sent");
     _statusCode = statusCode;
   }
 
   String get reasonPhrase => _findReasonPhrase(_statusCode);
   void set reasonPhrase(String reasonPhrase) {
     if (_outputStream != null) throw new HttpException("Header already sent");
     _reasonPhrase = reasonPhrase;
   }
 
   List<Cookie> get cookies {
     if (_cookies == null) _cookies = new List<Cookie>();
     return _cookies;
   }
 
   OutputStream get outputStream {
-    if (_state >= DONE) throw new HttpException("Response closed");
+    if (_state >= _HttpRequestResponseBase.DONE) {
+      throw new HttpException("Response closed");
+    }
     if (_outputStream == null) {
       _outputStream = new _HttpOutputStream(this);
     }
     return _outputStream;
   }
 
   DetachedSocket detachSocket() {
-    if (_state >= DONE) throw new HttpException("Response closed");
+    if (_state >= _HttpRequestResponseBase.DONE) {
+      throw new HttpException("Response closed");
+    }
     // Ensure that headers are written.
-    if (_state == START) {
+    if (_state == _HttpRequestResponseBase.START) {
       _writeHeader();
     }
-    _state = UPGRADED;
+    _state = _HttpRequestResponseBase.UPGRADED;
     // Ensure that any trailing data is written.
     _writeDone();
     // Indicate to the connection that the response handling is done.
     return _httpConnection._detachSocket();
   }
 
   // Delegate functions for the HttpOutputStream implementation.
   bool _streamWrite(List<int> buffer, bool copyBuffer) {
     if (_done) throw new HttpException("Response closed");
     return _write(buffer, copyBuffer);
   }
 
   bool _streamWriteFrom(List<int> buffer, int offset, int len) {
     if (_done) throw new HttpException("Response closed");
     return _writeList(buffer, offset, len);
   }
 
   void _streamFlush() {
     _httpConnection._flush();
   }
 
   void _streamClose() {
     _ensureHeadersSent();
-    _state = DONE;
+    _state = _HttpRequestResponseBase.DONE;
     // Stop tracking no pending write events.
     _httpConnection._onNoPendingWrites = null;
     // Ensure that any trailing data is written.
     _writeDone();
     // Indicate to the connection that the response handling is done.
     _httpConnection._responseClosed();
   }
 
   void _streamSetNoPendingWriteHandler(callback()) {
-    if (_state != DONE) {
+    if (_state != _HttpRequestResponseBase.DONE) {
       _httpConnection._onNoPendingWrites = callback;
     }
   }
 
   void _streamSetCloseHandler(callback()) {
     // TODO(sgjesse): Handle this.
   }
 
   void _streamSetErrorHandler(callback(e)) {
     _streamErrorHandler = callback;
@@ skipping 98 matching lines @@
     }
     // Add all the cookies set to the headers.
     if (_cookies != null) {
       _cookies.forEach((cookie) {
         _headers.add("set-cookie", cookie);
       });
     }
 
     // Write headers.
     bool allWritten = _writeHeaders();
-    _state = HEADER_SENT;
+    _state = _HttpRequestResponseBase.HEADER_SENT;
     return allWritten;
   }
 
   int _statusCode;  // Response status code.
   String _reasonPhrase;  // Response reason phrase.
   _HttpOutputStream _outputStream;
   Function _streamErrorHandler;
 }
 
 
@@ skipping 177 matching lines @@
   final int hashCode;
   static int _nextHashCode = 0;
 }
 
 
 // HTTP server connection over a socket.
 class _HttpConnection extends _HttpConnectionBase {
   _HttpConnection(HttpServer this._server) {
     _httpParser = new _HttpParser.requestParser();
     // Register HTTP parser callbacks.
-    _httpParser.requestStart = _onRequestStart;
-    _httpParser.headerReceived = _onHeaderReceived;
-    _httpParser.headersComplete = _onHeadersComplete;
+    _httpParser.requestStart = _onRequestReceived;
     _httpParser.dataReceived = _onDataReceived;
     _httpParser.dataEnd = _onDataEnd;
     _httpParser.error = _onError;
     _httpParser.closed = _onClosed;
     _httpParser.responseStart = (statusCode, reasonPhrase, version) {
       assert(false);
     };
   }
 
   void _onClosed() {
     _state |= _HttpConnectionBase.READ_CLOSED;
   }
 
   void _onError(e) {
     onError(e);
     // Propagate the error to the streams.
     if (_request != null && _request._streamErrorHandler != null) {
       _request._streamErrorHandler(e);
     }
     if (_response != null && _response._streamErrorHandler != null) {
       _response._streamErrorHandler(e);
     }
     if (_socket != null) _socket.close();
   }
 
-  void _onRequestStart(String method, String uri, String version) {
+  void _onRequestReceived(String method,
+                          String uri,
+                          String version,
+                          _HttpHeaders headers) {
     _state = _HttpConnectionBase.ACTIVE;
     // Create new request and response objects for this request.
     _request = new _HttpRequest(this);
     _response = new _HttpResponse(this);
-    _request._onRequestStart(method, uri, version);
+    _request._onRequestReceived(method, uri, version, headers);
     _request._protocolVersion = version;
     _response._protocolVersion = version;
     _response._headResponse = method == "HEAD";
-  }
-
-  void _onHeaderReceived(String name, String value) {
-    _request._onHeaderReceived(name, value);
-  }
-
-  void _onHeadersComplete() {
-    _request._onHeadersComplete();
     _response.persistentConnection = _httpParser.persistentConnection;
     if (onRequestReceived != null) {
       onRequestReceived(_request, _response);
     }
   }
 
   void _onDataReceived(List<int> data) {
     _request._onDataReceived(data);
   }
 
@@ skipping 164 matching lines @@
   _HttpSessionManager _sessionManagerInstance;
 }
 
 
 class _HttpClientRequest
     extends _HttpRequestResponseBase implements HttpClientRequest {
   _HttpClientRequest(String this._method,
                      Uri this._uri,
                      _HttpClientConnection connection)
       : super(connection) {
+    _headers = new _HttpHeaders();
     _connection = connection;
     // Default GET and HEAD requests to have no content.
     if (_method == "GET" || _method == "HEAD") {
       _contentLength = 0;
     }
   }
 
   void set contentLength(int contentLength) {
-    if (_state >= HEADER_SENT) throw new HttpException("Header already sent");
+    if (_state >= _HttpRequestResponseBase.HEADER_SENT) {
+      throw new HttpException("Header already sent");
+    }
     _contentLength = contentLength;
   }
 
   List<Cookie> get cookies {
     if (_cookies == null) _cookies = new List<Cookie>();
     return _cookies;
   }
 
   OutputStream get outputStream {
     if (_done) throw new HttpException("Request closed");
@@ skipping 13 matching lines @@
     if (_done) throw new HttpException("Request closed");
     return _writeList(buffer, offset, len);
   }
 
   void _streamFlush() {
     _httpConnection._flush();
   }
 
   void _streamClose() {
     _ensureHeadersSent();
-    _state = DONE;
+    _state = _HttpRequestResponseBase.DONE;
     // Stop tracking no pending write events.
     _httpConnection._onNoPendingWrites = null;
     // Ensure that any trailing data is written.
     _writeDone();
     _connection._requestClosed();
   }
 
   void _streamSetNoPendingWriteHandler(callback()) {
-    if (_state != DONE) {
+    if (_state != _HttpRequestResponseBase.DONE) {
       _httpConnection._onNoPendingWrites = callback;
     }
   }
 
   void _streamSetCloseHandler(callback()) {
     // TODO(sgjesse): Handle this.
   }
 
   void _streamSetErrorHandler(callback(e)) {
     _streamErrorHandler = callback;
@@ skipping 43 matching lines @@
         if (i > 0) sb.add("; ");
         sb.add(_cookies[i].name);
         sb.add("=");
         sb.add(_cookies[i].value);
       }
       _headers.add("cookie", sb.toString());
     }
 
     // Write headers.
     _writeHeaders();
-    _state = HEADER_SENT;
+    _state = _HttpRequestResponseBase.HEADER_SENT;
   }
 
   String _method;
   Uri _uri;
   _HttpClientConnection _connection;
   _HttpOutputStream _outputStream;
   Function _streamErrorHandler;
 }
 
 
@@ skipping 26 matching lines @@
     return _cookies;
   }
 
   InputStream get inputStream {
     if (_inputStream == null) {
       _inputStream = new _HttpInputStream(this);
     }
     return _inputStream;
   }
 
-  void _onResponseStart(int statusCode, String reasonPhrase, String version) {
+  void _onResponseReceived(int statusCode,
+                           String reasonPhrase,
+                           String version,
+                           _HttpHeaders headers) {
     _statusCode = statusCode;
     _reasonPhrase = reasonPhrase;
-  }
+    _headers = headers;
+    // Get parsed content length.
+    _contentLength = _httpConnection._httpParser.contentLength;
 
-  void _onHeaderReceived(String name, String value) {
-    _headers.add(name, value);
+    // Prepare for receiving data.
+    _headers._mutable = false;
+    _buffer = new _BufferList();
+
+    if (isRedirect && _connection.followRedirects) {
+      if (_connection._redirects == null ||
+          _connection._redirects.length < _connection.maxRedirects) {
+        // Check the location header.
+        List<String> location = headers[HttpHeaders.LOCATION];
+        if (location == null || location.length > 1) {
+           throw new RedirectException("Invalid redirect",
+                                       _connection._redirects);
+        }
+        // Check for redirect loop
+        if (_connection._redirects != null) {
+          Uri redirectUrl = new Uri.fromString(location[0]);
+          for (int i = 0; i < _connection._redirects.length; i++) {
+            if (_connection._redirects[i].location.toString() ==
+                redirectUrl.toString()) {
+              throw new RedirectLoopException(_connection._redirects);
+            }
+          }
+        }
+        // Drain body and redirect.
+        inputStream.onData = inputStream.read;
+        _connection.redirect();
+      } else {
+        throw new RedirectLimitExceededException(_connection._redirects);
+      }
+    } else if (statusCode == HttpStatus.UNAUTHORIZED) {
+      _handleUnauthorized();
+    } else if (_connection._onResponse != null) {
+      _connection._onResponse(this);
+    }
   }
 
   void _handleUnauthorized() {
 
     void retryRequest(_Credentials cr) {
       if (cr != null) {
         // Drain body and retry.
         // TODO(sgjesse): Support digest.
         if (cr.scheme == _AuthenticationScheme.BASIC) {
           inputStream.onData = inputStream.read;
@@ skipping 55 matching lines @@
       }
     }
 
     // Fall through to here to perform normal response handling if
     // there is no sensible authorization handling.
     if (_connection._onResponse != null) {
       _connection._onResponse(this);
     }
   }
 
-  void _onHeadersComplete() {
-    // Get parsed content length.
-    _contentLength = _httpConnection._httpParser.contentLength;
-
-    // Prepare for receiving data.
-    _headers._mutable = false;
-    _buffer = new _BufferList();
-
-    if (isRedirect && _connection.followRedirects) {
-      if (_connection._redirects == null ||
-          _connection._redirects.length < _connection.maxRedirects) {
-        // Check the location header.
-        List<String> location = headers[HttpHeaders.LOCATION];
-        if (location == null || location.length > 1) {
-           throw new RedirectException("Invalid redirect",
-                                       _connection._redirects);
-        }
-        // Check for redirect loop
-        if (_connection._redirects != null) {
-          Uri redirectUrl = new Uri.fromString(location[0]);
-          for (int i = 0; i < _connection._redirects.length; i++) {
-            if (_connection._redirects[i].location.toString() ==
-                redirectUrl.toString()) {
-              throw new RedirectLoopException(_connection._redirects);
-            }
-          }
-        }
-        // Drain body and redirect.
-        inputStream.onData = inputStream.read;
-        _connection.redirect();
-      } else {
-        throw new RedirectLimitExceededException(_connection._redirects);
-      }
-    } else if (statusCode == HttpStatus.UNAUTHORIZED) {
-      _handleUnauthorized();
-    } else if (_connection._onResponse != null) {
-      _connection._onResponse(this);
-    }
-  }
-
   void _onDataReceived(List<int> data) {
     _buffer.add(data);
     if (_inputStream != null) _inputStream._dataReceived();
   }
 
   void _onDataEnd() {
     if (_inputStream != null) {
       _inputStream._closeReceived();
     } else {
       inputStream._streamMarkedClosed = true;
@@ skipping 34 matching lines @@
     extends _HttpConnectionBase implements HttpClientConnection {
 
   _HttpClientConnection(_HttpClient this._client) {
     _httpParser = new _HttpParser.responseParser();
   }
 
   void _connectionEstablished(_SocketConnection socketConn) {
     super._connectionEstablished(socketConn._socket);
     _socketConn = socketConn;
     // Register HTTP parser callbacks.
-    _httpParser.responseStart = _onResponseStart;
-    _httpParser.headerReceived = _onHeaderReceived;
-    _httpParser.headersComplete = _onHeadersComplete;
+    _httpParser.responseStart = _onResponseReceived;
     _httpParser.dataReceived = _onDataReceived;
     _httpParser.dataEnd = _onDataEnd;
     _httpParser.error = _onError;
     _httpParser.closed = _onClosed;
     _httpParser.requestStart = (method, uri, version) { assert(false); };
     _state = _HttpConnectionBase.ACTIVE;
   }
 
   void _checkSocketDone() {
     if (_isAllDone) {
@@ skipping 52 matching lines @@
     }
     // Propagate the error to the streams.
     if (_response != null && _response._streamErrorHandler != null) {
        _response._streamErrorHandler(e);
     }
     if (_socketConn != null) {
       _client._closeSocketConnection(_socketConn);
     }
   }
 
-  void _onResponseStart(int statusCode, String reasonPhrase, String version) {
-    _response._onResponseStart(statusCode, reasonPhrase, version);
-  }
-
-  void _onHeaderReceived(String name, String value) {
-    _response._onHeaderReceived(name, value);
-  }
-
-  void _onHeadersComplete() {
-    _response._onHeadersComplete();
+  void _onResponseReceived(int statusCode,
+                           String reasonPhrase,
+                           String version,
+                           _HttpHeaders headers) {
+    _response._onResponseReceived(statusCode, reasonPhrase, version, headers);
   }
 
   void _onDataReceived(List<int> data) {
     _response._onDataReceived(data);
   }
 
   void _onDataEnd(bool close) {
     _response._onDataEnd();
     _state |= _HttpConnectionBase.RESPONSE_DONE;
     _checkSocketDone();
@@ skipping 602 matching lines @@
 
 
 class _RedirectInfo implements RedirectInfo {
   const _RedirectInfo(int this.statusCode,
                       String this.method,
                       Uri this.location);
   final int statusCode;
   final String method;
   final Uri location;
 }