Protect against receiving different BINDSTATUS_MIMETYPEAVAILABLE multiple tim...

chrome_frame/protocol_sink_wrap.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 <htiframe.h>
 #include <mshtml.h>
 
 #include "chrome_frame/protocol_sink_wrap.h"
 
 #include "base/logging.h"
@@ skipping 341 matching lines @@
     }
 
     if (size_read)
       *size_read = bytes_to_copy + new_data;
     return hr;
   }
 
   return read_fun_(protocol_, buffer, size, size_read);
 }
 
+// Attempt to detect ChromeFrame from HTTP headers when
+// BINDSTATUS_MIMETYPEAVAILABLE is received.
+// There are three possible outcomes: CHROME/OTHER/UNDETERMINED.
+// If UNDETERMINED we are going to sniff the content later in ReportData().
+//
+// With not-so-well-written software (mime filters/protocols/protocol patchers)
+// BINDSTATUS_MIMETYPEAVAILABLE might be fired multiple times with different
+// values for the same client.
+// If the renderer_type_ member is:
+// CHROME - 2nd (and any subsequent) BINDSTATUS_MIMETYPEAVAILABLE is ignored.
+// OTHER  - 2nd (and any subsequent) BINDSTATUS_MIMETYPEAVAILABLE is
+//          passed through.
+// UNDETERMINED - Try to detect ChromeFrame from HTTP headers (acts as if this
+//                is the first time BINDSTATUS_MIMETYPEAVAILABLE is received).
 HRESULT ProtData::ReportProgress(IInternetProtocolSink* delegate,
                                  ULONG status_code, LPCWSTR status_text) {
   switch (status_code) {
     case BINDSTATUS_DIRECTBIND:
       renderer_type_ = OTHER;
       break;
 
     case BINDSTATUS_REDIRECTING:
       url_.empty();
       if (status_text)
         url_ = status_text;
       break;
 
     case BINDSTATUS_SERVER_MIMETYPEAVAILABLE:
       has_server_mime_type_ = true;
       SaveSuggestedMimeType(status_text);
       return S_OK;
 
     // TODO(stoyan): BINDSTATUS_RAWMIMETYPE
     case BINDSTATUS_MIMETYPEAVAILABLE:
     case BINDSTATUS_VERIFIEDMIMETYPEAVAILABLE:
+      SaveSuggestedMimeType(status_text);
       // When Transaction is attached i.e. when existing BTS it terminated
       // and "converted" to BTO, events will be re-fired for the new sink,
       // but we may skip the renderer_type_ determination since it's already
       // done.
       if (renderer_type_ == UNDETERMINED) {
-        SaveSuggestedMimeType(status_text);
         // This may seem awkward. CBinding's implementation of IWinInetHttpInfo
         // will forward to CTransaction that will forward to the real protocol.
         // We may ask CTransaction (our protocol_ member) for IWinInetHttpInfo.
         ScopedComPtr<IWinInetHttpInfo> info;
         info.QueryFrom(delegate);
         renderer_type_ = DetermineRendererTypeFromMetaData(suggested_mime_type_,
                                                            url_, info);
       }
 
       if (renderer_type_ == CHROME) {
@@ skipping 449 matching lines @@
     // Explicit release, otherwise ~CComObjectStackEx will complain about
     // outstanding reference to us, because it runs before ~FakeProtocol
     prot.transaction_.Release();
   }
 }
 
 void TransactionHooks::RevertHooks() {
   vtable_patch::UnpatchInterfaceMethods(CTransaction_PatchInfo);
   vtable_patch::UnpatchInterfaceMethods(CTransaction2_PatchInfo);
 }