Windows QPA/QPlatformServices::openUrl(): Add work around for anchors…

… on local file URLs

Retrieve the browser executable and pass the URL as command line argument
in this case to work around ShellExecute() failing to handle anchors.

Pick-to: 6.4 6.3 6.2 5.15
Fixes: QTBUG-14460
Change-Id: I44ccd1126d5db6a387b36729837edc045908a670
Reviewed-by: André de la Rocha <[email protected]>

src/plugins/platforms/windows/qwindowsservices.cpp

@@ -14,6 +14,7 @@
 #include <QtCore/private/qwinregistry_p.h>
 
 #include <shlobj.h>
+#include <shlwapi.h>
 #include <intshcut.h>
 
 QT_BEGIN_NAMESPACE
@@ -25,12 +26,17 @@ enum { debug = 0 };
 class QWindowsShellExecuteThread : public QThread
 {
 public:
-    explicit QWindowsShellExecuteThread(const wchar_t *path) : m_path(path) { }
+    explicit QWindowsShellExecuteThread(const wchar_t *operation, const wchar_t *file,
+                                        const wchar_t *parameters)
+        : m_operation(operation)
+        , m_file(file)
+        , m_parameters(parameters) { }
 
     void run() override
     {
         if (SUCCEEDED(CoInitializeEx(NULL, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE))) {
-            m_result = ShellExecute(nullptr, nullptr, m_path, nullptr, nullptr, SW_SHOWNORMAL);
+            m_result = ShellExecute(nullptr, m_operation, m_file, m_parameters, nullptr,
+                                    SW_SHOWNORMAL);
             CoUninitialize();
         }
     }
@@ -39,9 +45,55 @@ class QWindowsShellExecuteThread : public QThread
 
 private:
     HINSTANCE m_result = nullptr;
-    const wchar_t *m_path;
+    const wchar_t *m_operation;
+    const wchar_t *m_file;
+    const wchar_t *m_parameters;
 };
 
+static QString msgShellExecuteFailed(const QUrl &url, quintptr code)
+{
+    QString result;
+    QTextStream(&result) <<"ShellExecute '" <<  url.toString() << "' failed (error " << code << ").";
+    return result;
+}
+
+// Retrieve the web browser and open the URL. This should be used for URLs with
+// fragments which don't work when using ShellExecute() directly (QTBUG-14460,
+// QTBUG-55300).
+static bool openWebBrowser(const QUrl &url)
+{
+    WCHAR browserExecutable[MAX_PATH] = {};
+    const wchar_t operation[] = L"open";
+    DWORD browserExecutableSize = MAX_PATH;
+    if (FAILED(AssocQueryString(0, ASSOCSTR_EXECUTABLE, L"http", operation,
+                                browserExecutable, &browserExecutableSize))) {
+        return false;
+    }
+    QString browser = QString::fromWCharArray(browserExecutable, browserExecutableSize - 1);
+    // Workaround for "old" MS Edge entries. Instead of LaunchWinApp.exe we can just use msedge.exe
+    if (browser.contains("LaunchWinApp.exe"_L1, Qt::CaseInsensitive))
+        browser = "msedge.exe"_L1;
+    const QString urlS = url.toString(QUrl::FullyEncoded);
+
+    // Run ShellExecute() in a thread since it may spin the event loop.
+    // Prevent it from interfering with processing of posted events (QTBUG-85676).
+    QWindowsShellExecuteThread thread(operation,
+                                      reinterpret_cast<const wchar_t *>(browser.utf16()),
+                                      reinterpret_cast<const wchar_t *>(urlS.utf16()));
+    thread.start();
+    thread.wait();
+
+    const auto result = reinterpret_cast<quintptr>(thread.result());
+    if (debug)
+        qDebug() << __FUNCTION__ << urlS << QString::fromWCharArray(browserExecutable) << result;
+    // ShellExecute returns a value greater than 32 if successful
+    if (result <= 32) {
+        qWarning("%s", qPrintable(msgShellExecuteFailed(url, result)));
+        return false;
+    }
+    return true;
+}
+
 static inline bool shellExecute(const QUrl &url)
 {
     const QString nativeFilePath = url.isLocalFile() && !url.hasFragment() && !url.hasQuery()
@@ -51,15 +103,17 @@ static inline bool shellExecute(const QUrl &url)
 
     // Run ShellExecute() in a thread since it may spin the event loop.
     // Prevent it from interfering with processing of posted events (QTBUG-85676).
-    QWindowsShellExecuteThread thread(reinterpret_cast<const wchar_t *>(nativeFilePath.utf16()));
+    QWindowsShellExecuteThread thread(nullptr,
+                                      reinterpret_cast<const wchar_t *>(nativeFilePath.utf16()),
+                                      nullptr);
     thread.start();
     thread.wait();
 
     const auto result = reinterpret_cast<quintptr>(thread.result());
 
     // ShellExecute returns a value greater than 32 if successful
     if (result <= 32) {
-        qWarning("ShellExecute '%ls' failed (error %zu).", qUtf16Printable(url.toString()), result);
+        qWarning("%s", qPrintable(msgShellExecuteFailed(url, result)));
         return false;
     }
     return true;
@@ -136,7 +190,8 @@ bool QWindowsServices::openUrl(const QUrl &url)
     const QString scheme = url.scheme();
     if (scheme == u"mailto" && launchMail(url))
         return true;
-    return shellExecute(url);
+    return url.isLocalFile() && url.hasFragment()
+        ? openWebBrowser(url) : shellExecute(url);
 }
 
 bool QWindowsServices::openDocument(const QUrl &url)