This seems like the best solution (free and NULL the dev pointer in dev_Close(), BEFORE GEdestroyDevDesc() has a go).
I think this should be safe because dev_Close() and GEdestroyDevDesc() are only called in one place (so your free() should always happen before GEdestroyDevDesc() and your free() shouldn't happen in any other, potentially inappropriate, context).
Paul On 09/23/14 03:15, Ritch Melton wrote:
I perused the source for RStudio and noticed that they had a similar problem. I didn't think that the GEDevDesc structure was exported, but apparently this is a worthwhile workaround to the defect. void GD_Close(pDevDesc dev) { ...elided... // explicitly free and then null out the dev pointer of the GEDevDesc // This is to avoid incompatabilities between the heap we are compiled with // and the heap R is compiled with (we observed this to a problem with // 64-bit R) std::free(s_pGEDevDesc->dev); s_pGEDevDesc->dev = NULL; // set GDDevDesc to NULL so we don't reference it again s_pGEDevDesc = NULL; } } I will On Fri, Sep 19, 2014 at 10:37 AM, Ritch Melton <skygu...@gmail.com> wrote:According to the "R Internals" document, for a custom device, I should create a pDevDesc structure that gets passed to GECreateDevDesc. ..elided... pDevDesc dev; /* Allocate and initialize the device driver data */ if (!(dev = (pDevDesc) calloc(1, sizeof(DevDesc)))) return 0; /* or error() */ /* set up device driver or free ’dev’ and error() */ gdd = GEcreateDevDesc(dev); GEaddDevice2(gdd, "dev_name"); ...elided... which indicates to me that the calling code owns the pDevDesc structure and should be responsible for freeing it. However, in GEdestroyDevDesc, that particular code calls free(dd->dev), freeing the pointer. In my case, I have a device implemented and created in a language that is using a different allocator. The pDevDesc I pass in is not owned by R and causes a crash on free with "dev.off()". I thought I could mitigate the issue, by making a call to the allocator R is using via an exported R function, such as R_alloc, but I did not see such a function available to me. I would like to know if I should be creating the pDevDesc via an imported alloc routine somehow? or is there a way to prevent this code from freeing the structure I pass in. Blue Skies, Ritch[[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
-- Dr Paul Murrell Department of Statistics The University of Auckland Private Bag 92019 Auckland New Zealand 64 9 3737599 x85392 p...@stat.auckland.ac.nz http://www.stat.auckland.ac.nz/~paul/ ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
