chrome_frame/http_negotiate.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_FRAME_HTTP_NEGOTIATE_H_
   6 #define CHROME_FRAME_HTTP_NEGOTIATE_H_
   7
   8 #include <shdeprecated.h>
   9 #include <urlmon.h>
  10
  11 #include <string>
  12
  13 #include "base/basictypes.h"
  14 #include "base/win/scoped_comptr.h"
  15
  16 // Typedefs for IHttpNegotiate methods.
  17 typedef HRESULT (STDMETHODCALLTYPE* IHttpNegotiate_BeginningTransaction_Fn)(
  18     IHttpNegotiate* me, LPCWSTR url, LPCWSTR headers, DWORD reserved,
  19     LPWSTR* additional_headers);
  20 typedef HRESULT (STDMETHODCALLTYPE* IHttpNegotiate_OnResponse_Fn)(
  21     IHttpNegotiate* me, DWORD response_code, LPCWSTR response_header,
  22     LPCWSTR request_header, LPWSTR* additional_request_headers);
  23
  24 // Typedefs for IBindStatusCallback methods.
  25 typedef HRESULT (STDMETHODCALLTYPE* IBindStatusCallback_StartBinding_Fn)(
  26     IBindStatusCallback* me, DWORD reserved, IBinding *binding);
  27
  28 // Typedefs for IInternetProtocolSink methods.
  29 typedef HRESULT (STDMETHODCALLTYPE* IInternetProtocolSink_ReportProgress_Fn)(
  30     IInternetProtocolSink* me, ULONG status_code, LPCWSTR status_text);
  31
  32 // Patches methods of urlmon's IHttpNegotiate implementation for the purposes
  33 // of adding to the http user agent header.
  34
  35 // Also patches one of the IBindStatusCallback implementations in urlmon to pick
  36 // up an IBinding during the StartBinding call. The IBinding implementor then
  37 // gets a patch applied to its IInternetProtocolSink's ReportProgress method.
  38 // The patched is there so that the reporting of the MIME type to the IBinding
  39 // implementor can be changed if an X-Chrome-Frame HTTP header is present
  40 // in the response headers. If anyone can suggest a more straightforward way of
  41 // doing this, I would be eternally grateful.
  42 class HttpNegotiatePatch {
  43   // class is not to be instantiated atm.
  44   HttpNegotiatePatch();
  45   ~HttpNegotiatePatch();
  46
  47  public:
  48   static bool Initialize();
  49   static void Uninitialize();
  50
  51   // Enables and disables the User Agent header modification. It is enabled
  52   // by default when the patch is installed.
  53   static void set_modify_user_agent(bool value) { modify_user_agent_ = value; }
  54
  55   // IHttpNegotiate patch methods
  56   static STDMETHODIMP BeginningTransaction(
  57       IHttpNegotiate_BeginningTransaction_Fn original, IHttpNegotiate* me,
  58       LPCWSTR url, LPCWSTR headers, DWORD reserved, LPWSTR* additional_headers);
  59
  60  protected:
  61   static HRESULT PatchHttpNegotiate(IUnknown* to_patch);
  62
  63  private:
  64   static bool modify_user_agent_;
  65
  66   DISALLOW_COPY_AND_ASSIGN(HttpNegotiatePatch);
  67 };
  68
  69 // From the latest urlmon.h. Symbol name prepended with LOCAL_ to
  70 // avoid conflict (and therefore build errors) for those building with
  71 // a newer Windows SDK.
  72 // TODO(robertshield): Remove this once we update our SDK version.
  73 extern const int LOCAL_BINDSTATUS_SERVER_MIMETYPEAVAILABLE;
  74
  75 // Scans |additional_headers| and |headers| for User-Agent header or grabs
  76 // the default User-Agent if none is found. Append "chromeframe" at the end
  77 // of the string. Returns the original content of |additional_headers| but
  78 // with the new User-Agent header. Somewhat unusual interface is dictated
  79 // because we use it in IHttpNegotiate::BeginningTransaction.
  80 // The function is a public since we want to use it from
  81 // UrlmonUrlRequest::BeginningTransaction for the unusual but yet possible case
  82 // when |headers| contains an User-Agent string.
  83 std::string AppendCFUserAgentString(LPCWSTR headers,
  84                                     LPCWSTR additional_headers);
  85
  86 // Adds or replaces the User-Agent header in a set of HTTP headers.
  87 // Arguments are the same as with AppendCFUserAgentString.
  88 std::string ReplaceOrAddUserAgent(LPCWSTR headers,
  89                                   const std::string& user_agent_value);
  90
  91 #endif  // CHROME_FRAME_HTTP_NEGOTIATE_H_