On Thu, May 31, 2012 at 2:35 AM, Greg Stein <gst...@gmail.com> wrote: > On Thu, May 31, 2012 at 12:43 AM, Vladimir Berezniker > <v...@hitechman.com> wrote: >> Patch 01 - Introduce macro >> >> [[[ >> JavaHL: Added CPPADDR_NULL_PTR macro to reduce amount of duplicate code >> checking C++ pointer extracted from the java object >> >> [ in subversion/bindings/javahl/native ] >> >> * JNIUtil.h >> (CPPADDR_NULL_PTR): New macro to test for NULL pointer and raise java >> exception if necessary >> ]]] > > Replying to just this patch. The second patch seems pretty mechanical. > And we're only looking at minor nits. > > (sorry, but the patch doesn't inline into this response, so let's just > be flexible here...) > > > The macro argument substitutions need to be parenthesized for safety. > So it would be: (expr) == NULL, and it would be: return (ret_val); > > Next bit: the indentation in the diff seems to be off. Are there TAB > characters in there? the JNIUTIL:: and the return lines have different > indents in the patch that I'm looking at. That is either sloppy SPC > character indents, or a TAB is present. > > Lastly, there is an extra space character before the ";" in the return > statement. That should be eliminated. > > > Fix the above three problems, and I'm +1 for you to commit just patch #1. > > I have not reviewed #2, but the first patch seems reasonable to > simplify (as done in #2). I also await others to comment on the > applicability of patch #2. > > I do seem to recall that C++ tried to do away with the preprocessor. > It would be nice to follow that ideal, but looking at this macro... I > have no idea how to map it into "proper, non-CPP concepts". If you > know, that would be better. Otherwise... meh. CPP is just fine with me > (and screw the C++ academic purity).
Like most things, C++ tried to reinvent the preprocessor and ended up with a half-baked solution which only partially replaces the thing it was intended to fix. We have several similar helper macros in the JavaHL C++ layer which do are similar in checking for error conditions (SVN_JNI_NULL_PTR_EX, for example) and possibly raising an exception. I don't know if the proposed macro is for a common situation, but there is precedent. -Hyrum -- uberSVN: Apache Subversion Made Easy http://www.uberSVN.com/