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

net/ftp/ftp_ctrl_response_buffer.cc

 // 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.
 
 #include "net/ftp/ftp_ctrl_response_buffer.h"
 
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "net/base/net_errors.h"
 
 namespace net {
 
 // static
 const int FtpCtrlResponse::kInvalidStatusCode = -1;
 
 int FtpCtrlResponseBuffer::ConsumeData(const char* data, int data_length) {
   buffer_.append(data, data_length);
   ExtractFullLinesFromBuffer();
 
   while (!lines_.empty()) {
     ParsedLine line = lines_.front();
     lines_.pop();
 
-    if (line_buf_.empty()) {
-      if (!line.is_complete)
-        return ERR_INVALID_RESPONSE;
-
-      response_buf_.status_code = line.status_code;
-      if (line.is_multiline) {
-        line_buf_ = line.status_text;
-      } else {
-        response_buf_.lines.push_back(line.status_text);
-        responses_.push(response_buf_);
-
-        // Prepare to handle following lines.
-        response_buf_ = FtpCtrlResponse();
-        line_buf_.clear();
-      }
-    } else {
+    if (multiline_) {
       if (!line.is_complete || line.status_code != response_buf_.status_code) {
         line_buf_.append(line.raw_text);
         continue;
       }
 
       response_buf_.lines.push_back(line_buf_);
 
       line_buf_ = line.status_text;
       DCHECK_EQ(line.status_code, response_buf_.status_code);
 
       if (!line.is_multiline) {
         response_buf_.lines.push_back(line_buf_);
         responses_.push(response_buf_);
 
         // Prepare to handle following lines.
         response_buf_ = FtpCtrlResponse();
         line_buf_.clear();
+        multiline_ = false;
+      }
+    } else {
+      if (!line.is_complete)
+        return ERR_INVALID_RESPONSE;
+
+      response_buf_.status_code = line.status_code;
+      if (line.is_multiline) {
+        line_buf_ = line.status_text;
+        multiline_ = true;
+      } else {
+        response_buf_.lines.push_back(line.status_text);
+        responses_.push(response_buf_);
+
+        // Prepare to handle following lines.
+        response_buf_ = FtpCtrlResponse();
+        line_buf_.clear();
       }
     }
   }
 
   return OK;
 }
 
 // static
 FtpCtrlResponseBuffer::ParsedLine FtpCtrlResponseBuffer::ParseLine(
     const std::string& line) {
@@ skipping 27 matching lines @@
   for (size_t i = 0; i < buffer_.length(); i++) {
     if (i >= 1 && buffer_[i - 1] == '\r' && buffer_[i] == '\n') {
       lines_.push(ParseLine(buffer_.substr(cut_pos, i - cut_pos - 1)));
       cut_pos = i + 1;
     }
   }
   buffer_.erase(0, cut_pos);
 }
 
 }  // namespace net