Merge "[HICN-528] Add progress bar to higet."

8 files changed, 110 insertions, 169 deletions

diff --git a/libtransport/src/hicn/transport/http/client_connection.cc b/libtransport/src/hicn/transport/http/client_connection.cc
index aa9cb0463..bd21bc448 100644
--- a/libtransport/src/hicn/transport/http/client_connection.cc
+++ b/libtransport/src/hicn/transport/http/client_connection.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -16,8 +16,6 @@
 #include <hicn/transport/http/client_connection.h>
 #include <hicn/transport/utils/hash.h>
 
-#include <fstream>
-
 #define DEFAULT_BETA 0.99
 #define DEFAULT_GAMMA 0.07
 
@@ -40,12 +38,6 @@ HTTPClientConnection::HTTPClientConnection()
           std::placeholders::_2));
 
   consumer_.setSocketOption(ConsumerCallbacksOptions::READ_CALLBACK, this);
-  consumer_.setSocketOption(
-      ConsumerCallbacksOptions::VERIFICATION_FAILED,
-      (ConsumerContentObjectVerificationFailedCallback)std::bind(
-          &HTTPClientConnection::onSignatureVerificationFailed, this,
-          std::placeholders::_1, std::placeholders::_2, std::placeholders::_3));
-  consumer_.setSocketOption(GeneralTransportOptions::VERIFY_SIGNATURE, false);
 
   consumer_.connect();
   std::shared_ptr<typename ConsumerSocket::Portal> portal;
@@ -54,31 +46,30 @@ HTTPClientConnection::HTTPClientConnection()
 }
 
 HTTPClientConnection::RC HTTPClientConnection::get(
-    const std::string &url, HTTPHeaders headers, HTTPPayload payload,
+    const std::string &url, HTTPHeaders headers, HTTPPayload &&payload,
     std::shared_ptr<HTTPResponse> response, ReadBytesCallback *callback,
     std::string ipv6_first_word) {
-  return sendRequest(url, HTTPMethod::GET, headers, payload, response, callback,
-                     ipv6_first_word);
+  return sendRequest(url, HTTPMethod::GET, headers, std::move(payload),
+                     response, callback, ipv6_first_word);
 }
 
 HTTPClientConnection::RC HTTPClientConnection::sendRequest(
     const std::string &url, HTTPMethod method, HTTPHeaders headers,
-    HTTPPayload payload, std::shared_ptr<HTTPResponse> response,
+    HTTPPayload &&payload, std::shared_ptr<HTTPResponse> response,
     ReadBytesCallback *callback, std::string ipv6_first_word) {
   current_url_ = url;
   read_bytes_callback_ = callback;
   if (!response) {
-    response = response_;
+    response_ = std::make_shared<HTTPResponse>();
+  } else {
+    response_ = response;
   }
 
   auto start = std::chrono::steady_clock::now();
-  HTTPRequest request(method, url, headers, payload);
-  response->clear();
+  request_.init(method, url, headers, std::move(payload));
 
   success_callback_ = [this, method = std::move(method), url = std::move(url),
-                       start = std::move(start),
-                       response = std::move(response)](
-                          std::size_t size) -> std::shared_ptr<HTTPResponse> {
+                       start = std::move(start)](std::size_t size) -> void {
     auto end = std::chrono::steady_clock::now();
     TRANSPORT_LOGI(
         "%s %s [%s] duration: %llu [usec] %zu [bytes]\n",
@@ -87,23 +78,15 @@ HTTPClientConnection::RC HTTPClientConnection::sendRequest(
             std::chrono::duration_cast<std::chrono::microseconds>(end - start)
                 .count(),
         size);
-
-    return response;
   };
 
-  sendRequestGetReply(request, response, ipv6_first_word);
+  sendRequestGetReply(ipv6_first_word);
   return return_code_;
 }
 
-void HTTPClientConnection::verifyPacketSignature(bool verify) {
-  consumer_.setSocketOption(GeneralTransportOptions::VERIFY_SIGNATURE, verify);
-}
-
-void HTTPClientConnection::sendRequestGetReply(
-    const HTTPRequest &request, std::shared_ptr<HTTPResponse> &response,
-    std::string &ipv6_first_word) {
-  const std::string &request_string = request.getRequestString();
-  const std::string &locator = request.getLocator();
+void HTTPClientConnection::sendRequestGetReply(std::string &ipv6_first_word) {
+  const std::string &request_string = request_.getRequestString();
+  const std::string &locator = request_.getLocator();
 
   // Hash it
 
@@ -116,7 +99,7 @@ void HTTPClientConnection::sendRequestGetReply(
       ConsumerCallbacksOptions::INTEREST_OUTPUT,
       (ConsumerInterestCallback)std::bind(
           &HTTPClientConnection::processLeavingInterest, this,
-          std::placeholders::_1, std::placeholders::_2, request_string));
+          std::placeholders::_1, std::placeholders::_2));
 
   // Factor hicn name using hash
   name_.str("");
@@ -142,9 +125,9 @@ void HTTPClientConnection::sendRequestGetReply(
   consumer_.stop();
 }
 
-HTTPResponse HTTPClientConnection::response() {
-  // response_->parse();
-  return std::move(*response_);
+std::shared_ptr<HTTPResponse> HTTPClientConnection::response() {
+  response_->coalescePayloadBuffer();
+  return response_;
 }
 
 bool HTTPClientConnection::verifyData(
@@ -159,10 +142,14 @@ bool HTTPClientConnection::verifyData(
 }
 
 void HTTPClientConnection::processLeavingInterest(
-    ConsumerSocket &c, const core::Interest &interest, std::string &payload) {
+    ConsumerSocket &c, const core::Interest &interest) {
   if (interest.payloadSize() == 0) {
     Interest &int2 = const_cast<Interest &>(interest);
+    auto payload = request_.getRequestString();
+    auto payload2 = request_.getPayload();
     int2.appendPayload((uint8_t *)payload.data(), payload.size());
+    if (payload2)
+      int2.appendPayload((uint8_t *)payload2->data(), payload2->length());
   }
 }
 
@@ -198,21 +185,11 @@ HTTPClientConnection &HTTPClientConnection::setCertificate(
   return *this;
 }
 
-VerificationPolicy HTTPClientConnection::onSignatureVerificationFailed(
-    ConsumerSocket &consumer, const core::ContentObject &content_object,
-    std::error_code reason) {
-  return VerificationPolicy::ACCEPT_PACKET;
-}
-
 // Read buffer management
 void HTTPClientConnection::readBufferAvailable(
     std::unique_ptr<utils::MemBuf> &&buffer) noexcept {
   if (!read_bytes_callback_) {
-    if (!read_buffer_) {
-      read_buffer_ = std::move(buffer);
-    } else {
-      read_buffer_->prependChain(std::move(buffer));
-    }
+    response_->appendResponseChunk(std::move(buffer));
   } else {
     read_bytes_callback_->onBytesReceived(std::move(buffer));
   }
@@ -230,18 +207,9 @@ void HTTPClientConnection::readError(const std::error_code ec) noexcept {
 }
 
 void HTTPClientConnection::readSuccess(std::size_t total_size) noexcept {
-  auto response = success_callback_(total_size);
+  success_callback_(total_size);
   if (read_bytes_callback_) {
     read_bytes_callback_->onSuccess(total_size);
-  } else {
-    response->reserve(total_size);
-    const utils::MemBuf *head = read_buffer_.get(), *current = head;
-    do {
-      response->insert(response->end(), current->data(), current->tail());
-      current = current->next();
-    } while (current != head);
-
-    read_buffer_.reset();
   }
 
   return_code_ = HTTPClientConnection::RC::DOWNLOAD_SUCCESS;
diff --git a/libtransport/src/hicn/transport/http/client_connection.h b/libtransport/src/hicn/transport/http/client_connection.h
index e001653ab..e93a37111 100644
--- a/libtransport/src/hicn/transport/http/client_connection.h
+++ b/libtransport/src/hicn/transport/http/client_connection.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -20,7 +20,6 @@
 #include <hicn/transport/http/response.h>
 #include <hicn/transport/interfaces/socket_consumer.h>
 #include <hicn/transport/interfaces/socket_producer.h>
-#include <hicn/transport/interfaces/verification_policy.h>
 #include <hicn/transport/utils/uri.h>
 
 #include <vector>
@@ -48,18 +47,18 @@ class HTTPClientConnection : public ConsumerSocket::ReadCallback {
   HTTPClientConnection();
 
   RC get(const std::string &url, HTTPHeaders headers = {},
-         HTTPPayload payload = {},
+         HTTPPayload &&payload = nullptr,
          std::shared_ptr<HTTPResponse> response = nullptr,
          ReadBytesCallback *callback = nullptr,
          std::string ipv6_first_word = "b001");
 
   RC sendRequest(const std::string &url, HTTPMethod method,
-                 HTTPHeaders headers = {}, HTTPPayload payload = {},
+                 HTTPHeaders headers = {}, HTTPPayload &&payload = nullptr,
                  std::shared_ptr<HTTPResponse> response = nullptr,
                  ReadBytesCallback *callback = nullptr,
                  std::string ipv6_first_word = "b001");
 
-  HTTPResponse response();
+  std::shared_ptr<HTTPResponse> response();
 
   HTTPClientConnection &stop();
 
@@ -69,23 +68,14 @@ class HTTPClientConnection : public ConsumerSocket::ReadCallback {
 
   HTTPClientConnection &setCertificate(const std::string &cert_path);
 
-  void verifyPacketSignature(bool verify);
-
  private:
-  void sendRequestGetReply(const HTTPRequest &request,
-                           std::shared_ptr<HTTPResponse> &response,
-                           std::string &ipv6_first_word);
+  void sendRequestGetReply(std::string &ipv6_first_word);
 
   bool verifyData(interface::ConsumerSocket &c,
                   const core::ContentObject &contentObject);
 
   void processLeavingInterest(interface::ConsumerSocket &c,
-                              const core::Interest &interest,
-                              std::string &payload);
-
-  VerificationPolicy onSignatureVerificationFailed(
-      ConsumerSocket &consumer, const core::ContentObject &content_object,
-      std::error_code reason);
+                              const core::Interest &interest);
 
   // Read callback
   bool isBufferMovable() noexcept override { return true; }
@@ -106,7 +96,7 @@ class HTTPClientConnection : public ConsumerSocket::ReadCallback {
   // The current hICN name used for downloading
   std::stringstream name_;
   // Function to be called when the read is successful
-  std::function<std::shared_ptr<HTTPResponse>(std::size_t)> success_callback_;
+  std::function<void(std::size_t)> success_callback_;
   // Return code for current download
   RC return_code_;
 
@@ -115,6 +105,8 @@ class HTTPClientConnection : public ConsumerSocket::ReadCallback {
   // any byte internally.
   ReadBytesCallback *read_bytes_callback_;
 
+  HTTPRequest request_;
+
   // Internal read buffer and HTTP response, to be used if the application does
   // not provide any read_bytes_callback
   std::unique_ptr<utils::MemBuf> read_buffer_;
diff --git a/libtransport/src/hicn/transport/http/message.h b/libtransport/src/hicn/transport/http/message.h
index 270dd3f0e..b8756224f 100644
--- a/libtransport/src/hicn/transport/http/message.h
+++ b/libtransport/src/hicn/transport/http/message.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -19,6 +19,8 @@
 #include <hicn/transport/portability/win_portability.h>
 #endif
 
+#include <hicn/transport/utils/membuf.h>
+
 #include <map>
 #include <sstream>
 #include <vector>
@@ -37,17 +39,25 @@ static std::map<HTTPMethod, std::string> method_map = {
 };
 
 typedef std::map<std::string, std::string> HTTPHeaders;
-typedef std::vector<uint8_t> HTTPPayload;
+typedef std::unique_ptr<utils::MemBuf> HTTPPayload;
 
 class HTTPMessage {
  public:
   virtual ~HTTPMessage() = default;
 
-  virtual const HTTPHeaders &getHeaders() = 0;
+  const HTTPHeaders getHeaders() { return headers_; };
+
+  void coalescePayloadBuffer() {
+    auto it = headers_.find("Content-Length");
+    if (it != headers_.end()) {
+      auto content_length = std::stoul(it->second);
+      payload_->gather(content_length);
+    }
+  }
 
-  virtual const HTTPPayload &getPayload() = 0;
+  HTTPPayload &&getPayload() { return std::move(payload_); }
 
-  virtual const std::string &getHttpVersion() const = 0;
+  std::string getHttpVersion() const { return http_version_; };
 
  protected:
   HTTPHeaders headers_;
diff --git a/libtransport/src/hicn/transport/http/request.cc b/libtransport/src/hicn/transport/http/request.cc
index 7a63b4f75..09f709642 100644
--- a/libtransport/src/hicn/transport/http/request.cc
+++ b/libtransport/src/hicn/transport/http/request.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -20,11 +20,15 @@ namespace transport {
 
 namespace http {
 
-// std::map<HTTPMethod, std::string> method_map
+HTTPRequest::HTTPRequest() {}
 
 HTTPRequest::HTTPRequest(HTTPMethod method, const std::string &url,
-                         const HTTPHeaders &headers,
-                         const HTTPPayload &payload) {
+                         const HTTPHeaders &headers, HTTPPayload &&payload) {
+  init(method, url, headers, std::move(payload));
+}
+
+void HTTPRequest::init(HTTPMethod method, const std::string &url,
+                       const HTTPHeaders &headers, HTTPPayload &&payload) {
   utils::Uri uri;
   uri.parse(url);
 
@@ -36,7 +40,7 @@ HTTPRequest::HTTPRequest(HTTPMethod method, const std::string &url,
   http_version_ = HTTP_VERSION;
 
   headers_ = headers;
-  payload_ = payload;
+  payload_ = std::move(payload);
 
   std::transform(locator_.begin(), locator_.end(), locator_.begin(), ::tolower);
 
@@ -50,33 +54,20 @@ HTTPRequest::HTTPRequest(HTTPMethod method, const std::string &url,
     stream << item.first << ": " << item.second << "\r\n";
   }
   stream << "\r\n";
-
-  if (payload.size() > 0) {
-    stream << payload.data();
-  }
-
   request_string_ = stream.str();
 }
 
-const std::string &HTTPRequest::getPort() const { return port_; }
+std::string HTTPRequest::getPort() const { return port_; }
 
-const std::string &HTTPRequest::getLocator() const { return locator_; }
+std::string HTTPRequest::getLocator() const { return locator_; }
 
-const std::string &HTTPRequest::getProtocol() const { return protocol_; }
+std::string HTTPRequest::getProtocol() const { return protocol_; }
 
-const std::string &HTTPRequest::getPath() const { return path_; }
+std::string HTTPRequest::getPath() const { return path_; }
 
-const std::string &HTTPRequest::getQueryString() const { return query_string_; }
-
-const HTTPHeaders &HTTPRequest::getHeaders() { return headers_; }
-
-const HTTPPayload &HTTPRequest::getPayload() { return payload_; }
-
-const std::string &HTTPRequest::getRequestString() const {
-  return request_string_;
-}
+std::string HTTPRequest::getQueryString() const { return query_string_; }
 
-const std::string &HTTPRequest::getHttpVersion() const { return http_version_; }
+std::string HTTPRequest::getRequestString() const { return request_string_; }
 
 }  // namespace http
 
diff --git a/libtransport/src/hicn/transport/http/request.h b/libtransport/src/hicn/transport/http/request.h
index 1202144c0..54904d696 100644
--- a/libtransport/src/hicn/transport/http/request.h
+++ b/libtransport/src/hicn/transport/http/request.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -27,32 +27,28 @@ namespace http {
 
 class HTTPRequest : public HTTPMessage {
  public:
+  HTTPRequest();
   HTTPRequest(HTTPMethod method, const std::string &url,
-              const HTTPHeaders &headers, const HTTPPayload &payload);
+              const HTTPHeaders &headers, HTTPPayload &&payload);
 
-  const std::string &getQueryString() const;
+  void init(HTTPMethod method, const std::string &url,
+            const HTTPHeaders &headers, HTTPPayload &&payload);
 
-  const std::string &getPath() const;
+  std::string getQueryString() const;
 
-  const std::string &getProtocol() const;
+  std::string getPath() const;
 
-  const std::string &getLocator() const;
+  std::string getProtocol() const;
 
-  const std::string &getPort() const;
+  std::string getLocator() const;
 
-  const std::string &getRequestString() const;
+  std::string getPort() const;
 
-  const HTTPHeaders &getHeaders() override;
-
-  const HTTPPayload &getPayload() override;
-
-  const std::string &getHttpVersion() const override;
+  std::string getRequestString() const;
 
  private:
   std::string query_string_, path_, protocol_, locator_, port_;
   std::string request_string_;
-  HTTPHeaders headers_;
-  HTTPPayload payload_;
 };
 
 }  // end namespace http
diff --git a/libtransport/src/hicn/transport/http/response.cc b/libtransport/src/hicn/transport/http/response.cc
index db7306cca..a2bc47e6b 100644
--- a/libtransport/src/hicn/transport/http/response.cc
+++ b/libtransport/src/hicn/transport/http/response.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -16,7 +16,8 @@
 #include <hicn/transport/errors/errors.h>
 #include <hicn/transport/http/response.h>
 
-#include <algorithm>
+#include <experimental/algorithm>
+#include <experimental/functional>
 
 #include <cstring>
 
@@ -26,30 +27,32 @@ namespace http {
 
 HTTPResponse::HTTPResponse() {}
 
-HTTPResponse::HTTPResponse(const HTTPHeaders &headers,
-                           const HTTPPayload &payload) {
-  headers_ = headers;
-  payload_ = payload;
+HTTPResponse::HTTPResponse(std::unique_ptr<utils::MemBuf> &&response) {
+  parse(std::move(response));
 }
 
-const HTTPHeaders &HTTPResponse::getHeaders() {
-  parse();
-  return headers_;
-}
-
-const HTTPPayload &HTTPResponse::getPayload() {
-  parse();
-  return payload_;
+void HTTPResponse::appendResponseChunk(
+    std::unique_ptr<utils::MemBuf> &&response_chunk) {
+  if (headers_.empty()) {
+    parse(std::move(response_chunk));
+  } else {
+    payload_->prependChain(std::move(response_chunk));
+  }
 }
 
-bool HTTPResponse::parseHeaders() {
+bool HTTPResponse::parseHeaders(std::unique_ptr<utils::MemBuf> &&buffer) {
   const char *crlf2 = "\r\n\r\n";
+  const char *begin = (const char *)buffer->data();
+  const char *end = begin + buffer->length();
   auto it =
-      std::search(this->begin(), this->end(), crlf2, crlf2 + strlen(crlf2));
+      std::experimental::search(begin, end,
+                                std::experimental::make_boyer_moore_searcher(
+                                    crlf2, crlf2 + strlen(crlf2)));
 
-  if (it != end()) {
+  if (it != end) {
+    buffer->trimStart(it + strlen(crlf2) - begin);
     std::stringstream ss;
-    ss.str(std::string(begin(), it + 1));
+    ss.str(std::string(begin, it));
 
     std::string line;
     getline(ss, line);
@@ -99,24 +102,15 @@ bool HTTPResponse::parseHeaders() {
     }
   }
 
+  payload_ = std::move(buffer);
+
   return true;
 }
 
-void HTTPResponse::parse() {
-  if (!parseHeaders()) {
+void HTTPResponse::parse(std::unique_ptr<utils::MemBuf> &&response) {
+  if (!parseHeaders(std::move(response))) {
     throw errors::RuntimeException("Malformed HTTP response");
   }
-
-  if (payload_.empty()) {
-    const char *crlf2 = "\r\n\r\n";
-    auto it =
-        std::search(this->begin(), this->end(), crlf2, crlf2 + strlen(crlf2));
-
-    if (it != this->end()) {
-      erase(begin(), it + strlen(crlf2));
-      payload_ = std::move(*dynamic_cast<std::vector<uint8_t> *>(this));
-    }
-  }
 }
 
 const std::string &HTTPResponse::getStatusCode() const { return status_code_; }
@@ -125,10 +119,6 @@ const std::string &HTTPResponse::getStatusString() const {
   return status_string_;
 }
 
-const std::string &HTTPResponse::getHttpVersion() const {
-  return http_version_;
-}
-
 }  // namespace http
 
 }  // namespace transport
\ No newline at end of file
diff --git a/libtransport/src/hicn/transport/http/response.h b/libtransport/src/hicn/transport/http/response.h
index b261a128a..7ef655059 100644
--- a/libtransport/src/hicn/transport/http/response.h
+++ b/libtransport/src/hicn/transport/http/response.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2020 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -26,26 +26,21 @@ namespace transport {
 
 namespace http {
 
-class HTTPResponse : public HTTPMessage, public std::vector<uint8_t> {
+class HTTPResponse : public HTTPMessage {
  public:
-  HTTPResponse(const HTTPHeaders &headers, const HTTPPayload &payload);
-
   HTTPResponse();
 
-  const HTTPHeaders &getHeaders() override;
+  HTTPResponse(std::unique_ptr<utils::MemBuf> &&response);
 
-  const HTTPPayload &getPayload() override;
+  void appendResponseChunk(std::unique_ptr<utils::MemBuf> &&response_chunk);
 
   const std::string &getStatusCode() const;
 
   const std::string &getStatusString() const;
 
-  const std::string &getHttpVersion() const override;
-
-  void parse();
+  void parse(std::unique_ptr<utils::MemBuf> &&response);
 
- private:
-  bool parseHeaders();
+  bool parseHeaders(std::unique_ptr<utils::MemBuf> &&buffer);
 
  private:
   std::string status_code_;
diff --git a/libtransport/src/hicn/transport/utils/membuf.h b/libtransport/src/hicn/transport/utils/membuf.h
index 66e9d7afa..9fc37dd25 100644
--- a/libtransport/src/hicn/transport/utils/membuf.h
+++ b/libtransport/src/hicn/transport/utils/membuf.h
@@ -526,12 +526,11 @@ class MemBuf {
   //  *
   //  * Returns ByteRange that points to the data MemBuf stores.
   //  */
-  // ByteRange coalesceWithHeadroomTailroom(
-  //     std::size_t newHeadroom,
-  //     std::size_t newTailroom) {
+  // ByteRange coalesceWithHeadroomTailroom(std::size_t newHeadroom,
+  //                                        std::size_t newTailroom) {
   //   if (isChained()) {
-  //     coalesceAndReallocate(
-  //         newHeadroom, computeChainDataLength(), this, newTailroom);
+  //     coalesceAndReallocate(newHeadroom, computeChainDataLength(), this,
+  //                           newTailroom);
   //   }
   //   return ByteRange(data_, length_);
   // }