I've found a way to prevent the crash, although I don't completely understand why (or if this is correct).
If I initialize the UI like this prior to calling the Wizard via symbol table lookups, etc (CallYCPFunction in the old python bindings): YUILoader::loadUI(); init_ui(YSettings::loadedUI()); Then I see no crashes or gui artifacts during run, so stack corruption seems resolved (init_ui() is same as from old python bindings). Also, if I tear down YUIComponent when the python program completes (so, prior to the ruby code tearing it down), then I don't see the crash at shutdown, like this: YUIComponent *c = YUIComponent::uiComponent(); if (c) c->result(YCPVoid()); I noticed after loading the UI using YUILoader, that at shutdown I got a segfault in ui_finalizer() (within ruby bindings Yast.cc). It appears that the singleton still holds a pointer, but the pointer is invalid (so it is not null, but the pointer is now invalid). Making that call early resolves the crash. On 10/09/2017 09:22 AM, David Mulder wrote: > If you install my python bindings, it's easy to reproduce. > > To install the bindings, first install these dependencies: > yast2-ycp-ui-bindings > autoconf-archive > swig > yast2-core-devel > > Clone the repo: > git clone https://github.com/dmulder/yast-python-bindings2.git > > Build/install: > cd yast-python-bindings2 > autoreconf -if > ./configure > make && sudo make install > > Then you'll need to add libpy2UI to your path: > LD_LIBRARY_PATH=$LD_LIBRARY_PATHPATH:/usr/lib64/YaST2/plugin > > Then to reproduce the failure, run `python` to open the interpreter, and > run: > > import yast > yast.init_ui('ncurses') > yast.Wizard.CreateDialog() > yast.UI.CloseDialog() > > It segfaults and generates a core dump. > > On 10/09/2017 09:08 AM, Josef Reidinger wrote: >> V Mon, 9 Oct 2017 08:54:35 -0600 >> David Mulder <[email protected]> napsáno: >> >>>> Problem is that you do not use Yast component system. In general all >>>> yast modules is attached to component system and you can call it >>>> with it. Old python bindings implement it properly with >>>> >>>> https://github.com/yast/yast-python-bindings/blob/master/src/YCP.cc >>> I added in use of the yast component system, for calling into the >>> Wizard class in the ruby code (branch ruby_bind on the same project). >>> This works, but there is now blatant stack corruption (crashing, UI >>> artifacts, etc). >>> Here is the crash at shutdown: >>> >>> #0 0x00007f7a704ad855 in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #1 0x00007f7a70389c4b in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #2 0x00007f7a7044029e in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #3 <signal handler called> >>> #4 0x0000000000000000 in ?? () >>> #5 0x00007f7a732e3643 in YUIComponent::result(YCPValue const&) () >>> from /usr/lib64/YaST2/plugin/libpy2UI.so.2 >> This crash looks like somewhere in ycp-ui-bindings. It looks like null >> pointer access. we probably need exact location in where in result it >> failed. Can you add there some trivial example of such crash so I can >> try it myself with all debug packages? >> >> Josef >> >>> #6 0x00007f7a6c58b4f0 in ?? () from >>> /usr/lib64/ruby/vendor_ruby/2.2.0/x86_64-linux-gnu/yastx.so >>> #7 0x00007f7a70496b4d in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #8 0x00007f7a704a78ce in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #9 0x00007f7a7049b3eb in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #10 0x00007f7a704a1224 in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #11 0x00007f7a704a5ffc in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #12 0x00007f7a704a6323 in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #13 0x00007f7a704a63f8 in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #14 0x00007f7a7039573c in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #15 0x00007f7a704a27e3 in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #16 0x00007f7a704a3a92 in ?? () from /usr/lib64/libruby2.2.so.2.2 >>> #17 0x00007f7a704a8bf0 in rb_eval_cmd () >>> from /usr/lib64/libruby2.2.so.2.2 #18 0x00007f7a703a0003 in ?? () >>> from /usr/lib64/libruby2.2.so.2.2 #19 0x00007f7a7038f55d in >>> rb_protect () from /usr/lib64/libruby2.2.so.2.2 #20 >>> 0x00007f7a703a1376 in ?? () from /usr/lib64/libruby2.2.so.2.2 #21 >>> 0x00007f7a703ab3d4 in rb_gc_call_finalizer_at_exit () >>> from /usr/lib64/libruby2.2.so.2.2 #22 0x00007f7a709bb80d in >>> YRuby::~YRuby() () from /usr/lib64/YaST2/plugin/libpy2lang_ruby.so >>> #23 0x00007f7a709bb8ee in YRuby::destroy() () from >>> /usr/lib64/YaST2/plugin/libpy2lang_ruby.so >>> #24 0x00007f7a709b66cd in Y2RubyComponent::~Y2RubyComponent() () >>> from /usr/lib64/YaST2/plugin/libpy2lang_ruby.so >>> #25 0x00007f7a709b67c9 in Y2RubyComponent::~Y2RubyComponent() () >>> from /usr/lib64/YaST2/plugin/libpy2lang_ruby.so >>> #26 0x00007f7a709b5aa1 in Y2CCRuby::~Y2CCRuby() () from >>> /usr/lib64/YaST2/plugin/libpy2lang_ruby.so >>> #27 0x00007f7a84b4e638 in __run_exit_handlers () from /lib64/libc.so.6 >>> #28 0x00007f7a84b4e68a in exit () from /lib64/libc.so.6 >>> #29 0x00007f7a84b37471 in __libc_start_main () from /lib64/libc.so.6 >>> #30 0x000055950bf6c7fa in _start () >>> >>> Any thoughts? >>>> which adds to python ability to call rest of component system. >>>> import is finding module like >>>> >>>> https://github.com/yast/yast-python-bindings/blob/master/src/YCP.cc#L107 >>>> >>>> and call it with >>>> >>>> https://github.com/yast/yast-python-bindings/blob/master/src/YCP.cc#L1238 >>>> >>>> so to call UI methods you need to import module "UI" and then with >>>> that call use method you want from UI namespace. >>>> >>>> >>>>>> 2. yast.py is basically reimplementation of yast stuff in python. >>>>>> I am not sure if it is right way, as anything you will need you >>>>>> have to reimplement >>>>> Yes, the yast.py code is wrong. I'm trying to think of a good way >>>>> to use the ruby Wizard code, etc. You mention there is a way to be >>>>> able to call functions between yast modules? >>>> yes, as I describe above. >>>> >>>>>> 3. your modules is not possible to call from rest of YaST. For >>>>>> ycp, perl and ruby it is possible to call it from each other. >>>>>> >>>>>> So in short. Your approach is more like wrapper for c++ parts >>>>>> ( currently only UI ) and rewrite for rest. >>>>>> >>>>>> In general if you need only UI from YaST, then I suggest to use >>>>>> direct approach and use libyui python bindings - >>>>>> https://github.com/libyui/libyui-bindings . But as I said this >>>>>> approach prevent you to use any part written in ruby and also rest >>>>>> of YaST cannot call your methods. >>>>>> >>>>>> It miss some layer from ycp-ui-bindings, but provide all needed to >>>>>> build UI. >>>>>> >>>>>> Josef >>>>>> -- David Mulder SUSE Labs Software Engineer - Samba [email protected] SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) -- To unsubscribe, e-mail: [email protected] To contact the owner, e-mail: [email protected]
