tor-browser

commit 8976fdf55d5ebabd160d5a7f378d1b8a81feba02
parent 78810a9f53f6e5271820be97a5e45145032e0983
Author: Duncan McIntosh <dmcintosh@mozilla.com>
Date:   Fri, 24 Oct 2025 22:02:34 +0000

Bug 1991233 - Ensure we always wait for the child process to accept input before leaving the desktop launcher. r=cdupuis

Differential Revision: https://phabricator.services.mozilla.com/D266504

Diffstat:
M
browser/app/desktop-launcher/main.cpp
 | 
48
++++++++++++++++++++++++++++--------------------

1 file changed, 28 insertions(+), 20 deletions(-)
diff --git a/browser/app/desktop-launcher/main.cpp b/browser/app/desktop-launcher/main.cpp
@@ -15,6 +15,30 @@
 #define DOWNLOAD_PAGE L"https://www.mozilla.org/firefox/new/"
 #define STUB_INSTALLER_ARGS L"/Prompt /LaunchedBy:desktoplauncher"
 
+/**
+ * Runs the provided path using the shell using the provided command-line
+ * parameters.
+ *
+ * Blocks until the application starts accepting input, or until a
+ * Windows-internal timeout is reached. Refer to SEE_MASK_WAITFORINPUTIDLE's
+ * documentation.
+ *
+ * @param path The path to the file or URL to run.
+ * @param params Command-line arguments to pass. May be null.
+ * @returns Truthy if the launch succeeded, false otherwise.
+ */
+static bool ExecuteAndWaitForIdle(const std::wstring& path,
+                                  const wchar_t* params) {
+  SHELLEXECUTEINFOW sei = {0};
+  sei.cbSize = sizeof(sei);
+  sei.fMask = SEE_MASK_WAITFORINPUTIDLE | SEE_MASK_NOASYNC;
+  sei.lpFile = path.c_str();
+  sei.lpParameters = params;
+  sei.nShow = SW_SHOWNORMAL;
+  ShellExecuteExW(&sei);
+  return (uintptr_t)sei.hInstApp > 32;
+}
+
 int wmain() {
   // For telemetry purposes, let's set the env variable to indicate that
   // we used the launcher to start Firefox
@@ -30,12 +54,7 @@ int wmain() {
   if (firefox_path.has_value()) {
     std::wcout << L"Found Firefox at path " << firefox_path.value()
                << std::endl;
-    HINSTANCE hinst =
-        ShellExecuteW(nullptr, nullptr, firefox_path.value().c_str(), nullptr,
-                      nullptr, SW_SHOWNORMAL);
-    if ((INT_PTR)hinst > 32) {
-      // ShellExecuteW returns a value > 32 on success. So we assume that
-      // Firefox has launched.
+    if (ExecuteAndWaitForIdle(firefox_path.value(), nullptr)) {
       std::wcout << L"Firefox launched" << std::endl;
       return 0;
     }
@@ -55,25 +74,14 @@ int wmain() {
   }
   // If the installer successfully downloaded, try to launch it
   if (download_completed) {
-    SHELLEXECUTEINFOW sei = {0};
-    sei.cbSize = sizeof(sei);
-    sei.fMask = SEE_MASK_WAITFORINPUTIDLE | SEE_MASK_NOASYNC;
-    sei.lpFile = tempfileName.value().c_str();
-    sei.lpParameters = STUB_INSTALLER_ARGS;
-    sei.nShow = SW_SHOWNORMAL;
-    ShellExecuteExW(&sei);
-
-    if ((INT_PTR)sei.hInstApp > 32) {
-      // ShellExecuteW returns a value > 32 on success.
+    if (ExecuteAndWaitForIdle(tempfileName.value(), STUB_INSTALLER_ARGS)) {
       std::wcout << L"Firefox installer launched" << std::endl;
       return 0;
     }
   }
+
   // If that doesn't work, open the download page in the default browser
-  HINSTANCE default_browser_hinst = ShellExecuteW(
-      nullptr, nullptr, DOWNLOAD_PAGE, nullptr, nullptr, SW_SHOWNORMAL);
-  if ((INT_PTR)default_browser_hinst > 32) {
-    // ShellExecuteW returns a value > 32 on success.
+  if (ExecuteAndWaitForIdle(DOWNLOAD_PAGE, nullptr)) {
     std::wcout << L"Opened default browser to the download page" << std::endl;
   }
   return 0;