Crashes when opening a plugin that wants to render using gtk when suil isn't compiled with gtk

[rncbc]

Crashes when opening a plugin that wants to render using gtk when suil isn't compiled with gtk

[rncbc]

On 09/25/2016 04:55 PM, Simon van der Veldt wrote:

Qtractor hard crashes when I add a plugin that (apparently) wants to
render it's UI using GTK. When enabling debugging I get the following
error message:

|suil error: Unable to open wrap module
/usr/lib64/suil-0/libsuil_gtk2_in_qt4.so
(/usr/lib64/suil-0/libsuil_gtk2_in_qt4.so: cannot open shared object
file: No such file or directory) |

This is easily solved by compiling suil with gtk support, but I do think
that Qtractor shouldn't crash when it can't find a lib. Is there a way
to prevent this?

libsuil_gtk2_in_qt4 object or specific package must be installed on your
system; it is part of suil, not of qtractor.

Also, there seem to be some checks to prevent these situations in
|configure.ac|
https://github.com/rncbc/qtractor/blob/master/configure.ac#L1251 but
these seem to explicitly only check when not using Qt4. That might be an
error?
(For reference: I'm running a Qt4 build)

yes, those checks are for an alternative to libsuil_gtk2_in_qt5, which
is only available on suil >= 0.8.4 but still no official announcement of
this latest suil release.

byee

rncbc aka. Rui Nuno Capela

[simonvanderveldt]

libsuil_gtk2_in_qt4 object or specific package must be installed on your
system; it is part of suil, not of qtractor.

Yeah, that's what I did, maybe I worded it in an unclear way. I recompiled libsuil with gtk enabled.
But I do feel that it shouldn't cause a segfault in Qtractor. I'm able to figure out what's happening by creating a debug build, but for people who know less about these things it's not really a good user experience.
Or is it impossible to catch these types of errors?

yes, those checks are for an alternative to libsuil_gtk2_in_qt5, which
is only available on suil >= 0.8.4 but still no official announcement of
this latest suil release.

Ah, I see. And that alternative is Qt5 specific?

[rncbc]

On 09/25/2016 08:13 PM, Simon van der Veldt wrote:

libsuil_gtk2_in_qt4 object or specific package must be installed on your
system; it is part of suil, not of qtractor.

Yeah, that's what I did, maybe I worded it in an unclear way. I
recompiled libsuil with gtk enabled.
But I do feel that it shouldn't cause a segfault in Qtractor. I'm able
to figure out what's happening by creating a debug build, but for people
who know less about these things it's not really a good user experience.
Or is it impossible to catch these types of errors?

afaict. it seems a packaging/install/deployment error: you have to
install ALL the objects or packages that were ganged on same libsuil
build. otherwise you get segfault/crashes due to missing installed
components (the API assumes is there, but on the file-system isn't).

yes, those checks are for an alternative to libsuil_gtk2_in_qt5, which
is only available on suil >= 0.8.4 but still no official announcement of
this latest suil release.

Ah, I see. And that alternative is Qt5 specific?

yes. exactly.

byee

rncbc aka. Rui Nuno Capela

[simonvanderveldt]

@rncbc I'm not sure I fully understand. Do you mean the build system for Qtractor does build-time checks if libraries exist/have certain feature enabled?
Because the libsuil I had and used to build Qtractor didn't have gtk enabled but the compiled Qtractor apparently still expected it to be there.

[rncbc]

Do you mean the build system for Qtractor does build-time checks if libraries exist/have certain feature enabled?

not that if libraries exist but it checks on the API with suil_ui_supported() call that tells whether some component wrapper or library was compiled in at libsuil.so build time, and is featured or supported (eg. libsuil_qtk2_in_qt4.so is there somewhere available.

however, it seems, that although it might tell it's supported (as it was built on a former time), it might not be actually deployed (installed) on the system and the missing is only evident at runtime, when the host (qtractor) goes into actually show up a plugin's GtkUI and is greeted with a crash (eg. libsuil_gtk2_in_qt4.so not found).

byee

rncbc aka. Rui Nuno Capela

[simonvanderveldt]

yes, those checks are for an alternative to libsuil_gtk2_in_qt5, which
is only available on suil >= 0.8.4 but still no official announcement of
this latest suil release.

There has been a release of suil 0.10.0 now :)
Is there anything needed to use this or will it just work by updating suil and rebuilding Qtractor?

not that if libraries exist but it checks on the API with suil_ui_supported() call that tells whether some component wrapper or library was compiled in at libsuil.so build time, and is featured or supported (eg. libsuil_qtk2_in_qt4.so is there somewhere available.

however, it seems, that although it might tell it's supported (as it was built on a former time), it might not be actually deployed (installed) on the system and the missing is only evident at runtime, when the host (qtractor) goes into actually show up a plugin's GtkUI and is greeted with a crash (eg. libsuil_gtk2_in_qt4.so not found).

It seems this isn't working as it should because the libsuil I had installed didn't have the gtk2 in Qt4 support enabled, yet I was still allowed to add GTK based plugins from within Qtractor causing the crash.

[rncbc]

unless you're using kxstudio repos--which tend to use libsuil-static and thus qtractor must also get updated--you're all fine to deploy libsuil 0.10.0 and go.

byee