net/ftp: Fix control response parsing for a corner cases where the first line...

net/ftp/ftp_ctrl_response_buffer.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.  Use of this
 // source code is governed by a BSD-style license that can be found in the
 // LICENSE file.
 
 #ifndef NET_FTP_FTP_CTRL_RESPONSE_BUFFER_H_
 #define NET_FTP_FTP_CTRL_RESPONSE_BUFFER_H_
 
 #include <queue>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 
 namespace net {
 
 struct FtpCtrlResponse {
   static const int kInvalidStatusCode;
 
   FtpCtrlResponse() : status_code(kInvalidStatusCode) {}
 
   int status_code;                 // Three-digit status code.
   std::vector<std::string> lines;  // Response lines, without CRLFs.
 };
 
 class FtpCtrlResponseBuffer {
  public:
-  FtpCtrlResponseBuffer() {}
+  FtpCtrlResponseBuffer() : multiline_(false) {
+  }
 
   // Called when data is received from the control socket. Returns error code.
   int ConsumeData(const char* data, int data_length);
 
   bool ResponseAvailable() const {
     return !responses_.empty();
   }
 
   // Returns the next response. It is an error to call this function
   // unless ResponseAvailable returns true.
@@ skipping 36 matching lines @@
 
   static ParsedLine ParseLine(const std::string& line);
 
   void ExtractFullLinesFromBuffer();
 
   // We keep not-yet-parsed data in a string buffer.
   std::string buffer_;
 
   std::queue<ParsedLine> lines_;
 
+  // True if we are in the middle of parsing a multi-line response.
+  bool multiline_;
+
   // When parsing a multiline response, we don't know beforehand if a line
   // will have a continuation. So always store last line of multiline response
   // so we can append the continuation to it.
   std::string line_buf_;
 
   // Keep the response data while we add all lines to it.
   FtpCtrlResponse response_buf_;
 
   // As we read full responses (possibly multiline), we add them to the queue.
   std::queue<FtpCtrlResponse> responses_;
 
   DISALLOW_COPY_AND_ASSIGN(FtpCtrlResponseBuffer);
 };
 
 }  // namespace net
 
 #endif  // NET_FTP_FTP_CTRL_RESPONSE_BUFFER_H_