Bug 1914807: Prevent duplicate Dock icons when restarting applications on macOS. r=mac-reviewers,application-update-reviewers,bradwerth,nalexander

Differential Revision: https://phabricator.services.mozilla.com/D222326

toolkit/mozapps/update/updater/updater.cpp

@@ -3025,6 +3025,15 @@ int NS_main(int argc, NS_tchar** argv) {
   bool isDMGInstall = false;
 
 #ifdef XP_MACOSX
+  if (argc > 2 && NS_tstrcmp(argv[1], NS_T("--openAppBundle")) == 0) {
+    // We have been asked to open a .app bundle. The path to the .app bundle and
+    // any command line arguments have been passed to us as arguments after
+    // "--openAppBundle", so remove the first two arguments and launch the .app
+    // bundle.
+    LaunchMacApp(argc - 2, (const char**)argv + 2);
+    return 0;
+  }
+
   // We want to control file permissions explicitly, or else we could end up
   // corrupting installs for other users on the system. Accordingly, set the
   // umask to 0 for all file creations below and reset it on exit. See Bug

toolkit/xre/MacLaunchHelper.mm

@@ -119,6 +119,10 @@ void LaunchMacApp(int aArgc, char** aArgv) {
   MacAutoreleasePool pool;
 
   NSString* launchPath = [NSString stringWithUTF8String:aArgv[0]];
+  if (![launchPath hasSuffix:@".app"]) {
+    LaunchChildMac(aArgc, aArgv, 0);
+    return;
+  }
   NSMutableArray* arguments = [NSMutableArray arrayWithCapacity:aArgc - 1];
   for (int i = 1; i < aArgc; i++) {
     [arguments addObject:[NSString stringWithUTF8String:aArgv[i]]];

toolkit/xre/nsCommandLineServiceMac.mm

@@ -8,6 +8,7 @@
 #include "nsString.h"
 #include "nsTArray.h"
 #include "MacApplicationDelegate.h"
+#include "MacAutoreleasePool.h"
 #include <cstring>
 #include <Cocoa/Cocoa.h>
 
@@ -41,6 +42,8 @@ void AddToCommandLine(const char* inArgText) {
 // Caller has ownership of argv and is responsible for freeing the allocated
 // memory.
 void SetupMacCommandLine(int& argc, char**& argv, bool forRestart) {
+  mozilla::MacAutoreleasePool pool;
+
   sArgs = static_cast<char**>(malloc(kArgsGrowSize * sizeof(char*)));
   if (!sArgs) {
     return;
@@ -50,6 +53,19 @@ void SetupMacCommandLine(int& argc, char**& argv, bool forRestart) {
   sArgsUsed = 0;
 
   NSString* path = [NSString stringWithUTF8String:argv[0]];
+  if (forRestart &&
+      [path hasSuffix:[NSString stringWithUTF8String:MOZ_APP_NAME]]) {
+    // When we restart, we ask the updater binary to restart us instead.
+    // This avoids duplicate Dock icons, by giving this process a chance to
+    // shut down before the new process is launched.
+    // Essentially, we are using the updater as a relauncher process.
+    NSString* updaterPath = [[path stringByDeletingLastPathComponent]
+        stringByAppendingPathComponent:
+            @"updater.app/Contents/MacOS/org.mozilla.updater"];
+    AddToCommandLine(updaterPath.UTF8String);
+    AddToCommandLine("--openAppBundle");
+  }
+
   // We adjust the path to point to the .app bundle, rather than the executable
   // itself, to allow for the use of the NSWorkspace API for launching and
   // relaunching the application. We intentionally exclude the