Screensavers don't work in 'live cd'-mode

[idefix]

Using the hrev36674 nightly cd (​haiku-r1a2-rc-r36674-x86gcc2hybrid-cd.zip) in live-mode (VESA video).

Steps to reproduce:

1. go to the Modules tab in ScreenSaver
2. click on the Test button

The preview will turn black, but the selected screensaver won't run.

3. click on the list in the ScreenSaver window

ScreenSaver will now crash:

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This GDB was configured as "i586-pc-haiku"...(no debugging symbols found)

[tcsetpgrp failed in terminal_inferior: Invalid Argument]
Thread 514 caused an exception: Segment violation
Reading symbols from /boot/system/runtime_loader...done.
Loaded symbols for /boot/system/runtime_loader
Reading symbols from /boot/system/lib/libtracker.so...done.
Loaded symbols for /boot/system/lib/libtracker.so
Reading symbols from /boot/system/lib/libscreensaver.so...done.
Loaded symbols for /boot/system/lib/libscreensaver.so
Reading symbols from /boot/system/lib/libbe.so...done.
Loaded symbols for /boot/system/lib/libbe.so
Reading symbols from /boot/system/lib/libstdc++.r4.so...done.
Loaded symbols for /boot/system/lib/libstdc++.r4.so
Reading symbols from /boot/system/lib/libroot.so...done.
Loaded symbols for /boot/system/lib/libroot.so
Reading symbols from /boot/system/lib/libtranslation.so...done.
Loaded symbols for /boot/system/lib/libtranslation.so
Reading symbols from /boot/system/lib/libgame.so...done.
Loaded symbols for /boot/system/lib/libgame.so
Reading symbols from /boot/system/lib/libtextencoding.so...done.
Loaded symbols for /boot/system/lib/libtextencoding.so
Reading symbols from /boot/system/lib/libmedia.so...done.
Loaded symbols for /boot/system/lib/libmedia.so
[tcsetpgrp failed in terminal_inferior: Invalid Argument]
[Switching to team /boot/system/preferences/ScreenSaver (505) thread w>ScreenSaver (514)]
0xbf800000 in ?? ()
(gdb) bt
#0  0xbf800000 in ?? ()
#1  0x0020c6c0 in ModulesView::_CloseSaver ()
#2  0x0020bd55 in ModulesView::MessageReceived ()
#3  0x004c673f in BLooper::DispatchMessage () from /boot/system/lib/libbe.so
#4  0x0058a32d in BWindow::DispatchMessage () from /boot/system/lib/libbe.so
#5  0x0058e4e4 in BWindow::task_looper () from /boot/system/lib/libbe.so
#6  0x004c7c9b in BLooper::_task0_ () from /boot/system/lib/libbe.so
#7  0x006f50b2 in thread_entry () from /boot/system/lib/libroot.so
#8  0x700c1fec in ?? ()
(gdb) 

[idefix]

Further testing reveals that the screensavers don't work at all (as in not after the set timeout and not when you put the mouse in the set hotspot-corner).

[idefix]

They do work when Haiku has been installed to a harddisk. Only when running in 'live cd'-mode, the screensavers don't work (but the previews do work).

Updated summary and component accordingly.

[idefix]

It looks like this has been fixed, as they do work with a hrev37017 nightly cd (​haiku-nightly-r37017-x86gcc2hybrid-cd.zip).

This ticket can be closed.

[korli]

Please reopen if needed.

[idefix]

Sorry, I was too quick with my conclusion. The screensavers still don't work when running in 'live cd'-mode.

They will however start to work after invoking screen_blanker once in Terminal:

1. boot a nightly cd
2. wait 15 minutes, or start ScreenSaver and click on the Test button

• the currently selected screensaver (Blackness) will not start (the screen doesn't turn black)

3. crash screenSaver by clicking on the list (if you didn't wait 15 minutes at step 2)
4. open Terminal and start screen_blanker

• the currently selected screensaver (Blackness) starts (the screen turns black)

5. start ScreenSaver and click on the Test button

• the currently selected screensaver (Blackness) does now start normally (the screen turns black)

[jackburton]

screen_blanker is launched by signature, by the screensaver input server addon (line 181), and that won't work until the registrar has examined the screen_blanked binary and written the needed attributes. That's why waiting 15 minutes or executing screen_blanker manually once does the trick. I noticed a similar problem with Terminal, but only on real hardware, for some reason: opt-alt-T launches the terminal only if I launch it manually at least once.

A workaround to this problem would be to check for an error, and then try to launch the screen_blanker by path, like we do for the media_server_addon.

[korli]

Please check again with hrev37120 or upper. Thanks.

[idefix]

With hrev37125 (​haiku-nightly-r37125-x86gcc2hybrid-cd.zip), the screen saver will start after 15 minutes. It won't however start when clicking the Test button in ScreenSaver (on the plus side: it won't crash anymore either). It looks like the code in hrev37120 also needs to be added to ScreenSaver preferences.

[korli]

Replying to idefix:

With hrev37125 (​haiku-nightly-r37125-x86gcc2hybrid-cd.zip), the screen saver will start after 15 minutes. It won't however start when clicking the Test button in ScreenSaver (on the plus side: it won't crash anymore either). It looks like the code in hrev37120 also needs to be added to ScreenSaver preferences.

I checked and the 'Test' button doesn't launch anything, so the fix must be fairly different.

[idefix]

I don't know if I understand you correctly, but in comment:8 I had something in mind like:

src/preferences/screensaver/ScreenSaverWindow.cpp

@@ -365 +365 @@
         }
 
         case kMsgTestSaver:
+        {
             SaveState();
             fSettings.Save();
 
@@ -372 +373 @@
 
             be_roster->StartWatching(BMessenger(this, this->Looper()),
                 B_REQUEST_QUIT);
-            be_roster->Launch(SCREEN_BLANKER_SIG, &fSettings.Message(),
-                &fScreenSaverTestTeamId);
+
+            if (be_roster->Launch(SCREEN_BLANKER_SIG, &fSettings.Message(),
+                &fScreenSaverTestTeamId) == B_OK)
+                break;
+
+            // Try really hard to launch it. It's very likely that this fails,
+            // when we run from the CD and there is only an incomplete mime
+            // database for example...
+            BPath path;
+            if (find_directory(B_SYSTEM_BIN_DIRECTORY, &path) != B_OK
+                || path.Append("screen_blanker") != B_OK) {
+                path.SetTo("/boot/system/bin/screen_blanker");
+            }
+            BEntry entry(path.Path());
+            entry_ref ref;
+            if (entry.GetRef(&ref) == B_OK) {
+                be_roster->Launch(&ref, &fSettings.Message(),
+                    &fScreenSaverTestTeamId);
+            }
+
             break;
+        }
 
         case kMsgAddSaver:
             fFilePanel->Show();

Which should fix the problem with the Test button in ScreenSaver (although I haven't test it).

[korli]

OK I understood and meant the preview, not the test button. Sorry about that. I applied your hint in hrev37305. Please check. Thanks a lot!

[idefix]

The Test button now also works (tested with hrev37307 (​haiku-nightly-r37307-x86gcc2hybrid-cd.zip)). Thanks!

[korli]

Thanks for the feedback!