Preventing crash in IE driver when attaching to IWebBrowser2 object fails.

Author: jimevans

Diff for: cpp/iedriver/BrowserFactory.cpp

@@ -446,13 +446,20 @@ bool BrowserFactory::AttachToBrowserUsingShellWindows(
                              reinterpret_cast<LPARAM>(process_window_info));
           if (process_window_info->hwndBrowser != NULL) {
             hr = shell_window_variant.pdispVal->QueryInterface<IWebBrowser2>(&browser);
-            process_window_info->pBrowser = browser.Detach();
+            if (FAILED(hr)) {
+              LOGHR(WARN, hr) << "Found browser window using ShellWindows "
+                              << "API, but QueryInterface for IWebBrowser2 "
+                              << "failed, so could not attach to the browser.";
+            } else {
+              process_window_info->pBrowser = browser.Detach();
+            }
             break;
           }
         }
       }
     }
-    if (process_window_info->hwndBrowser == NULL) {
+    if (process_window_info->hwndBrowser == NULL ||
+        process_window_info->pBrowser == NULL) {
       ::Sleep(250);
     }
   }
@@ -463,6 +470,11 @@ bool BrowserFactory::AttachToBrowserUsingShellWindows(
                                              this->browser_attach_timeout_);
     return false;
   }
+
+  if (process_window_info->pBrowser == NULL) {
+    *error_message = ATTACH_FAILURE_ERROR_MESSAGE;
+    return false;
+  }
   return true;
 }
 

Diff for: cpp/iedriver/BrowserFactory.h

@@ -42,6 +42,7 @@
 #define PROTECTED_MODE_SETTING_ERROR_MESSAGE "Protected Mode settings are not the same for all zones. Enable Protected Mode must be set to the same value (enabled or disabled) for all zones."
 #define ZOOM_SETTING_ERROR_MESSAGE "Browser zoom level was set to %d%%. It should be set to 100%%"
 #define ATTACH_TIMEOUT_ERROR_MESSAGE "Could not find an Internet Explorer window belonging to the process with ID %d within %d milliseconds."
+#define ATTACH_FAILURE_ERROR_MESSAGE "Found browser window using ShellWindows API, but could not attach to the browser IWebBrowser2 object."
 #define CREATEPROCESS_REGISTRY_ERROR_MESSAGE "Unable to use CreateProcess() API. To use CreateProcess() with Internet Explorer 8 or higher, the value of registry setting in HEKY_CURRENT_USER\\Software\\Microsoft\\Internet Explorer\\Main\\TabProcGrowth must be '0'."
 
 #define ZONE_MY_COMPUTER L"0"

Diff for: cpp/iedriver/Generated/atoms.h

@@ -9,6 +9,12 @@ available via the project downloads page. Changes in "revision" field indicate
 private releases checked into the prebuilts directory of the source tree, but
 not made generally available on the downloads page.
 
+v2.45.0.1
+=========
+ * Updates to JavaScript automation atoms.
+ * Changed to prevent crash when driver fails to connect to IWebBrowser2
+   object.
+
 v2.45.0.0
 =========
  * Release to synchronize with release of Selenium project.