BRoster::Launch() eventually launches the application in question

in several steps:
1. early pre-registration with the registrar ("I wanna launch the
   app, make sure noone interferes.")
2. load the app image
3. finish pre-registration with the registrar ("I have launched
   the app, here is its team ID.")
4. start app main thread
5. send "on launch" messages to the app (argv, refs, others)

If the app is already running or being launched, 1. fails with a
conclusive error code and returns the team ID and the pre-registration
token of the app. Steps 2 - 4 are skipped and only the messages are
delivered using the team ID returned by 1.

This change fixes a race condition: The failed early pre-registration
request obviously cannot return the team ID, if the other thread
launching the app has not finished step 3 yet. Thus the argv/refs
message would not get delivered and Launch() would not return the
correct team ID.

Now we wait for the pre-registration to be finished in this case, using
the former _IsAppPreRegistered() mechanism, which already provided
such a waiting feature for one request. It has been extended to
accomodate an arbitrary number of waiting requests and renamed to
_IsAppRegistered().

This fixed bug #763.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@18728 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kits/app/Application.cpp

@@ -318,8 +318,10 @@ BApplication::_InitData(const char *signature, bool initGUI, status_t *_error)
 	bool preRegistered = false;
 	app_info appInfo;
 	if (fInitError == B_OK && !isRegistrar) {
-		preRegistered = BRoster::Private().IsAppPreRegistered(&ref, team,
-							&appInfo);
+		if (BRoster::Private().IsAppRegistered(&ref, team, 0, &preRegistered,
+				&appInfo) != B_OK) {
+			preRegistered = false;
+		}
 	}
 	if (preRegistered) {
 		// we are pre-registered => the app info has been filled in

src/kits/app/Roster.cpp

@@ -1424,10 +1424,12 @@ BRoster::_AddApplication(const char *mimeSig, const entry_ref *ref,
 		error = request.AddInt32("port", port);
 	if (error == B_OK)
 		error = request.AddBool("full_registration", fullReg);
+
 	// send the request
 	BMessage reply;
 	if (error == B_OK)
 		error = fMessenger.SendMessage(&request, &reply);
+
 	// evaluate the reply
 	if (error == B_OK) {
 		if (reply.what == B_REG_SUCCESS) {
@@ -1442,8 +1444,11 @@ BRoster::_AddApplication(const char *mimeSig, const entry_ref *ref,
 		} else {
 			if (reply.FindInt32("error", &error) != B_OK)
 				error = B_ERROR;
+			// get team and token from the reply
 			if (otherTeam && reply.FindInt32("other_team", otherTeam) != B_OK)
 				*otherTeam = -1;
+			if (pToken && reply.FindInt32("token", (int32*)pToken) != B_OK)
+				*pToken = 0;
 		}
 	}
 	return error;
@@ -1580,46 +1585,66 @@ BRoster::_CompleteRegistration(team_id team, thread_id thread,
 	return error;
 }
 
-// IsAppPreRegistered
-/*!	\brief Returns whether an application is pre-registered.
+// _IsAppRegistered
+/*!	\brief Returns whether an application is registered.
 
 	If the application is indeed pre-registered and \a info is not \c NULL,
 	the methods fills in the app_info structure pointed to by \a info.
 
 	\param ref An entry_ref referring to the app's executable
-	\param team The app's team ID
+	\param team The app's team ID. May be -1, if \a token is given.
+	\param token The app's pre-registration token. May be 0, if \a team is
+				 given.
+	\param preRegistered: Pointer to a pre-allocated bool to be filled in
+		   by this method, indicating whether or not the app was
+		   pre-registered.
 	\param info A pointer to a pre-allocated app_info structure to be filled
 		   in by this method (may be \c NULL)
-	\return \c true, if the application is pre-registered, \c false if not.
+	\return
+		- \c B_OK, if the application is registered and all requested
+		  information could be retrieved,
+		- another error code, if the app is not registered or an error occurred.
 */
-bool
-BRoster::_IsAppPreRegistered(const entry_ref *ref, team_id team,
-	app_info *info) const
+status_t
+BRoster::_IsAppRegistered(const entry_ref *ref, team_id team,
+	uint32 token, bool *preRegistered, app_info *info) const
 {
 	status_t error = B_OK;
+
 	// compose the request message
-	BMessage request(B_REG_IS_APP_PRE_REGISTERED);
+	BMessage request(B_REG_IS_APP_REGISTERED);
 	if (error == B_OK && ref)
 		error = request.AddRef("ref", ref);
 	if (error == B_OK && team >= 0)
 		error = request.AddInt32("team", team);
+	if (error == B_OK && token > 0)
+		error = request.AddInt32("token", (int32)token);
+	
 	// send the request
 	BMessage reply;
 	if (error == B_OK)
 		error = fMessenger.SendMessage(&request, &reply);
 
 	// evaluate the reply
+	bool isRegistered = false;
 	bool isPreRegistered = false;
 	if (error == B_OK) {
 		if (reply.what == B_REG_SUCCESS) {
-			if (reply.FindBool("pre-registered", &isPreRegistered) != B_OK)
+			if (reply.FindBool("registered", &isRegistered) != B_OK
+				|| !isRegistered
+				|| reply.FindBool("pre-registered", &isPreRegistered) != B_OK) {
 				error = B_ERROR;
-			if (error == B_OK && isPreRegistered && info)
+			}
+
+			if (error == B_OK && preRegistered)
+				*preRegistered = isPreRegistered;
+			if (error == B_OK && info)
 				error = find_message_app_info(&reply, info);
 		} else if (reply.FindInt32("error", &error) != B_OK)
 			error = B_ERROR;
 	}
-	return error == B_OK && isPreRegistered;
+	
+	return error;
 }
 
 // RemovePreRegApp
@@ -1815,10 +1840,13 @@ BRoster::_LaunchApp(const char *mimeType, const entry_ref *ref,
 		if (error == B_ALREADY_RUNNING) {
 			DBG(OUT("  already running\n"));
 			alreadyRunning = true;
-			error = B_OK;
+
 			// get the app flags for the running application
-			if (GetRunningAppInfo(team, &appInfo) == B_OK)
+			error = _IsAppRegistered(&appRef, team, appToken, NULL, &appInfo);
+			if (error == B_OK) {
 				otherAppFlags = appInfo.flags;
+				team = appInfo.team;
+			}
 		}
 		DBG(OUT("  pre-register: %s (%lx)\n", strerror(error), error));
 	}