Initial import of the Chrome Frame codebase. Integration in chrome.gyp coming...

chrome_frame/bho.h

Index: chrome_frame/bho.h
===================================================================
--- chrome_frame/bho.h	(revision 0)
+++ chrome_frame/bho.h	(revision 0)
@@ -0,0 +1,102 @@
+// 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.
+
+#ifndef CHROME_FRAME_BHO_H_
+#define CHROME_FRAME_BHO_H_
+
+#include <string>
+
+#include <atlbase.h>
+#include <atlcom.h>
+#include <exdisp.h>
+#include <exdispid.h>
+#include <mshtml.h>
+#include <shdeprecated.h>
+
+#include "chrome_tab.h"  // NOLINT
+#include "chrome_frame/resource.h"
+#include "grit/chrome_frame_resources.h"
+
+class PatchHelper {
+ public:
+  enum State { UNKNOWN, PATCH_IBROWSER, PATCH_IBROWSER_OK, PATCH_PROTOCOL };
+  PatchHelper() : state_(UNKNOWN) {
+  }
+
+  State state() const {
+    return state_;
+  }
+
+  void InitializeAndPatchProtocolsIfNeeded();
+  void PatchBrowserService(IBrowserService* p);
+  void UnpatchIfNeeded();
+ protected:
+  State state_;
+};
+
+// Single global variable
+extern PatchHelper g_patch_helper;
+
+class ATL_NO_VTABLE Bho
+  : public CComObjectRootEx<CComSingleThreadModel>,
+    public CComCoClass<Bho, &CLSID_ChromeFrameBHO>,
+    public IObjectWithSiteImpl<Bho>,
+    public IDispEventSimpleImpl<0, Bho, &DIID_DWebBrowserEvents2> {
+ public:
+  typedef HRESULT (STDMETHODCALLTYPE* IBrowserService_OnHttpEquiv_Fn)(
+      IBrowserService* browser, IShellView* shell_view, BOOL done,
+      VARIANT* in_arg, VARIANT* out_arg);
+
+DECLARE_REGISTRY_RESOURCEID(IDR_BHO)
+DECLARE_NOT_AGGREGATABLE(Bho)
+DECLARE_PROTECT_FINAL_CONSTRUCT()
+
+BEGIN_COM_MAP(Bho)
+  COM_INTERFACE_ENTRY(IObjectWithSite)
+END_COM_MAP()
+
+BEGIN_SINK_MAP(Bho)
+ SINK_ENTRY_INFO(0, DIID_DWebBrowserEvents2, DISPID_BEFORENAVIGATE2,
+                 BeforeNavigate2, &kBeforeNavigate2Info)
+END_SINK_MAP()
+
+  // Lifetime management methods
+  Bho();
+
+  HRESULT FinalConstruct();
+  void FinalRelease();
+
+  // IObjectWithSite
+  STDMETHODIMP SetSite(IUnknown* site);
+  STDMETHOD(BeforeNavigate2)(IDispatch* dispatch, VARIANT* url, VARIANT* flags,
+      VARIANT* target_frame_name, VARIANT* post_data, VARIANT* headers,
+      VARIANT_BOOL* cancel);
+
+  // mshtml sends an IOleCommandTarget::Exec of OLECMDID_HTTPEQUIV
+  // (and OLECMDID_HTTPEQUIV_DONE) as soon as it parses a meta tag.
+  // It also sends contents of the meta tag as an argument. IEFrame
+  // handles this in IBrowserService::OnHttpEquiv.  So this allows
+  // us to sniff the META tag by simply patching it. The renderer
+  // switching can be achieved by cancelling original navigation
+  // and issuing a new one using IWebBrowser2->Navigate2.
+  static HRESULT STDMETHODCALLTYPE OnHttpEquiv(
+      IBrowserService_OnHttpEquiv_Fn original_httpequiv,
+      IBrowserService* browser, IShellView* shell_view, BOOL done,
+      VARIANT* in_arg, VARIANT* out_arg);
+
+ protected:
+  bool PatchProtocolHandler(const CLSID& handler_clsid);
+  static bool HasSubFrames(IWebBrowser2* web_browser2);
+  static HRESULT SwitchRenderer(IWebBrowser2* web_browser2,
+      IBrowserService* browser, IShellView* shell_view,
+      const wchar_t* meta_tag);
+
+  static _ATL_FUNC_INFO kBeforeNavigate2Info;
+};
+
+// Add Bho to class library table so IE can CoCreate it.
+OBJECT_ENTRY_AUTO(CLSID_ChromeFrameBHO, Bho);
+
+#endif  // CHROME_FRAME_BHO_H_
+