Buffet: Move buffet over to platform2 from src/platform/buffet.

This change also open-sources buffet. The only change in this CL
is the removal of the Makefile and addition of the buffet.gyp file.

BUG=chromium:355180
TEST=USE=buffet emerge-gizmo platform2

Change-Id: Ibf8d3ac3f38313f82a9c07d79932b6f30130f9c5

buffet/http_transport_curl.h

diff --git a/buffet/http_transport_curl.h b/buffet/http_transport_curl.h
new file mode 100644
index 0000000..ab2ea2b
--- /dev/null
+++ b/buffet/http_transport_curl.h
@@ -0,0 +1,166 @@
+// Copyright 2014 The Chromium OS 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 BUFFET_HTTP_TRANSPORT_CURL_H_
+#define BUFFET_HTTP_TRANSPORT_CURL_H_
+
+#include <map>
+#include <curl/curl.h>
+
+#include "buffet/http_request.h"
+
+namespace chromeos {
+namespace http {
+namespace curl {
+
+///////////////////////////////////////////////////////////////////////////////
+// A particular implementation of TransportInterface that uses libcurl for
+// HTTP communications. This class (as TransportInterface interface)
+// is used by http::Request and http::Response classes to provide HTTP
+// functionality to the clients.
+///////////////////////////////////////////////////////////////////////////////
+class Transport : public TransportInterface {
+ public:
+  // Standard constructor. |url| is the full request URL with protocol
+  // schema, host address, resource path as well as optional query parameters
+  // and/or user name/password. |method| is one of HTTP request verbs such as
+  // "GET", "POST", etc. If nullptr is specified, "GET" is assumed.
+  Transport(std::string const& url, char const* method);
+  ~Transport();
+
+  // Returns the current request/response stage.
+  virtual Stage GetStage() const override { return stage_; }
+
+  // Implementation of Request::AddRange.
+  virtual void AddRange(int64_t bytes) override;
+  virtual void AddRange(uint64_t from_byte, uint64_t to_byte) override;
+
+  // Implementation of Request::SetAccept/Request::GetAccept.
+  virtual void SetAccept(char const* acceptMimeTypes) override {
+    accept_ = acceptMimeTypes;
+  }
+  virtual std::string GetAccept() const override;
+
+  // Implementation of Request::GetRequestURL.
+  virtual std::string GetRequestURL() const override { return request_url_; }
+
+  // Implementation of Request::SetContentType/Request::GetContentType.
+  virtual void SetContentType(char const* content_type) override {
+    content_type_ = content_type;
+  }
+  virtual std::string GetContentType() const override { return content_type_; }
+
+  // Implementation of Request::AddHeader.
+  virtual void AddHeader(char const* header, char const* value) override;
+
+  // Implementation of Request::RemoveHeader.
+  virtual void RemoveHeader(char const* header) override;
+
+  // Implementation of Request::AddRequestBody.
+  virtual bool AddRequestBody(void const* data, size_t size) override;
+
+  // Implementation of Request::SetMethod/Request::GetMethod.
+  virtual void SetMethod(char const* method) override { method_ = method; }
+  virtual std::string GetMethod() const override { return method_; }
+
+  // Implementation of Request::SetReferer/Request::GetReferer.
+  virtual void SetReferer(char const* referer) override { referer_ = referer; }
+  virtual std::string GetReferer() const override { return referer_; }
+
+  // Implementation of Request::SetUserAgent/Request::GetUserAgent.
+  virtual void SetUserAgent(char const* user_agent) override {
+    user_agent_ = user_agent;
+  }
+  virtual std::string GetUserAgent() const override { return user_agent_; }
+
+  // Sends the HTTP request to the server. Used by Request::GetResponse().
+  virtual bool Perform() override;
+
+  // Implementation of Response::GetStatusCode.
+  virtual int GetResponseStatusCode() const override;
+
+  // Implementation of Response::GetStatusText.
+  virtual std::string GetResponseStatusText() const override {
+    return status_text_;
+  }
+
+  // Implementation of Response::GetHeader.
+  virtual std::string GetResponseHeader(char const* header_name) const override;
+
+  // Implementation of Response::GetData.
+  virtual std::vector<unsigned char> const& GetResponseData() const override {
+    return response_data_;
+  }
+
+  // Implementation of Response::GetErrorMessage.
+  virtual std::string GetErrorMessage() const override { return error_; }
+
+  // Closes the connection and frees up internal data
+  virtual void Close() override;
+
+ private:
+  std::vector<std::pair<std::string, std::string>> GetHeaders() const;
+
+  // Write data callback. Used by CURL when receiving response data.
+  static size_t write_callback(char* ptr, size_t size, size_t num, void* data);
+  // Read data callback. Used by CURL when sending request body data.
+  static size_t read_callback(char* ptr, size_t size, size_t num, void* data);
+  // Write header data callback. Used by CURL when receiving response headers.
+  static size_t header_callback(char* ptr, size_t size, size_t num, void* data);
+
+  // Full request URL, such as "http://www.host.com/path/to/object"
+  std::string request_url_;
+  // HTTP request verb, such as "GET", "POST", "PUT", ...
+  std::string method_;
+
+  // Referrer URL, if any. Sent to the server via "Referer: " header.
+  std::string referer_;
+  // User agent string, if any. Sent to the server via "User-Agent: " header.
+  std::string user_agent_;
+  // Content type of the request body data.
+  // Sent to the server via "Content-Type: " header.
+  std::string content_type_;
+  // List of acceptable response data types.
+  // Sent to the server via "Accept: " header.
+  std::string accept_ = "*/*";
+
+  // List of optional request headers provided by the caller.
+  // After request has been sent, contains the received response headers.
+  std::map<std::string, std::string> headers_;
+  // List of optional data ranges to request partial content from the server.
+  // Sent to thr server as "Range: " header.
+  std::vector<std::pair<uint64_t, uint64_t>> ranges_;
+  // Binary data for request body.
+  std::vector<unsigned char> request_data_;
+  // Read pointer for request data. Used when streaming data to the server.
+  size_t request_data_ptr_ = 0;
+
+  // Received response data.
+  std::vector<unsigned char> response_data_;
+
+  // Current progress stage.
+  Stage stage_ = Stage::failed;
+  // CURL error message in case request fails completely.
+  std::string error_;
+  // Reponse status text, such as "OK" for 200, or "Forbidden" for 403
+  std::string status_text_;
+  // Flag used when parsing response headers to separate the response status
+  // from the rest of response headers.
+  bool status_text_set_ = false;
+
+  // range_value_omitted is used in |ranges_| list to indicate omitted value.
+  // E.g. range (10,range_value_omitted) represents bytes from 10 to the end
+  // of the data stream.
+  static const uint64_t range_value_omitted = (uint64_t)-1;
+
+  CURL* curl_handle_ = nullptr;
+
+  DISALLOW_COPY_AND_ASSIGN(Transport);
+};
+
+} // namespace curl
+} // namespace http
+} // namespace chromeos
+
+#endif // BUFFET_HTTP_TRANSPORT_CURL_H_