Fix chunk and content-length encoding (cpp-netlib#759)

* The entire body has already been placed in partial_parsed, so don't direct the callback to append any more data

* Cleaned up indentation.
Don't potentially access memory beyond the end of the string buffer.
In the case of a partial chunk, exit the loop. Continuing to search for crlf in the middle of a binary data chunk can result in an infinite loop, and wasn't the right logic.

Author: LoopinFool

boost/network/protocol/http/client/connection/async_protocol_handler.hpp

@@ -361,22 +361,23 @@ struct http_async_protocol_handler {
     for (typename string_type::const_iterator iter =
              std::search(begin, partial_parsed.end(), crlf.begin(), crlf.end());
          iter != partial_parsed.end();
-         iter =
-             std::search(begin, partial_parsed.end(), crlf.begin(), crlf.end())) {
+         iter = std::search(begin, partial_parsed.end(), crlf.begin(), crlf.end())) {
       string_type line(begin, iter);
       if (line.empty()) {
-          std::advance(iter, 2);
-          begin = iter;
-          continue;
+        std::advance(iter, 2);
+        begin = iter;
+        continue;
       }
       std::stringstream stream(line);
       int len;
       stream >> std::hex >> len;
       std::advance(iter, 2);
       if (!len) return true;
       if (len <= partial_parsed.end() - iter) {
-        std::advance(iter, len + 2);
-      }
+        std::advance(iter, len);
+	  } else {
+		return false;
+	  }
       begin = iter;
     }
     return false;
@@ -391,7 +392,7 @@ struct http_async_protocol_handler {
     partial_parsed.append(part_begin, it);
     part_begin = part.begin();
     if (check_parse_body_complete()) {
-      callback(boost::asio::error::eof, bytes);
+      callback(boost::asio::error::eof, 0);
     } else {
       delegate_->read_some(
           boost::asio::mutable_buffers_1(part.data(), part.size()), callback);