Hi All On Sat, 22 Sep 2018 09:40:35 +0300 Adrian Bunk <[email protected]> wrote: > Control: clone -1 -2 > Control: reassign -1 squeak-vm > Control: reassign -2 squeak-plugins-scratch > > On Sun, Aug 05, 2018 at 07:33:58PM +0200, Bernhard Übelacker wrote: > > Hello Wouter, > > thanks for this additional information. > > > > I could reproduce the issue with a usb webcam inside a buster amd64 VM. > > Unfortunately this camera button was with the german translation not > > visible with the small resolution of that VM. > > > > It took a little time to get into the smalltalk side of things. > > But I think I have found a problem - on the c side of the plugins. > > > > > > > > (gdb) bt > > #0 0x00007fffafa33c82 in convertImageRGB24toARGB32 (cam=0x7fffafa37180 > > <camInfo>) at ./unix/plugins/CameraPlugin/sqCamera-linux.c:333 > > #1 0x00007fffafa33f2a in convertImage (cam=0x7fffafa37180 <camInfo>) at > > ./unix/plugins/CameraPlugin/sqCamera-linux.c:412 > > #2 0x00007fffafa34d10 in CameraGetFrame (camNum=1, buf=0x7fffb2b9fcb4 "", > > pixelCount=76800) at ./unix/plugins/CameraPlugin/sqCamera-linux.c:836 > > #3 0x00007fffafa3352c in primGetFrame () at > > ./unix/src/plugins/CameraPlugin/CameraPlugin.c:160 > > #4 0x0000555555578ca4 in dispatchFunctionPointer > > (aFunctionPointer=0x7fffafa33461 <primGetFrame>) at > > ./build-tree/gnu-interp.c:3809 > > #5 0x00005555555769f8 in callExternalPrimitive (functionID=0x7fffafa33461 > > <primGetFrame>) at ./build-tree/gnu-interp.c:2512 > > #6 0x000055555558fc92 in primitiveExternalCall () at > > ./build-tree/gnu-interp.c:17732 > > #7 0x0000555555578ca4 in dispatchFunctionPointer > > (aFunctionPointer=0x55555558faf0 <primitiveExternalCall>) at > > ./build-tree/gnu-interp.c:3809 > > #8 0x000055555558227a in interpret () at ./build-tree/gnu-interp.c:9339 > > #9 0x00005555555a7cef in main (argc=8, argv=0x7fffffffe2a8, > > envp=0x7fffffffe2f0) at ./unix/vm/sqUnixMain.c:1458 > > > > (gdb) list convertImageRGB24toARGB32 > > 319 static void > > 320 convertImageRGB24toARGB32 (camPtr cam) > > 321 { > > 322 unsigned char *src = cam->inBuffer; > > 323 unsigned long int *dst = cam->sqBuffer; <-- > > sizeof(*dst) == 8, should be 4 ? > > 324 unsigned long int pixelCount = cam->sqPixels; > > 325 unsigned long int pixel; > > 326 int i; > > 327 > > 328 if (0 == dst) return; > > 329 > > 330 for ( i = 0; i < pixelCount; i++) { > > 331 pixel = 0xFF000000 | (*src++ << 16); > > 332 pixel = pixel | (*src++ << 8); > > 333 *dst++ = pixel | *src++; > > 334 } > > 335 } > > > > > > > > Here the buffer allocated in the squeak-vm is given to primGetFrame > > and gets finally the image written to in convertImageRGB24toARGB32. > > Unfortunately these conversion functions use "unsigned long int *dst", > > with a long int having a size of 8 bytes at amd64, while we got > > just 4 bytes per pixel reserved from squeak-vm, therefore > > overrunning our reserved buffer. > > > > > > When just installing the packages the plugin so.CameraPlugin gets > > used from the package squeak-plugins-scratch.
I fixed that in the Camera Plugin last year and it is used in the current, OpenSmalltalk-VM/Cog-based Squeak as such: https://github.com/OpenSmalltalk/opensmalltalk-vm/commit/203de239312943d2d8be86ecec306a6f9971f49e I think this diff is independent of OpenSmalltalk VM and should work with the interpreter-based sources of Squeak VM 4.10 as used with this package and Scratch. Hope this helps. Best regards -Tobias
