On Fri, 14 Dec 2007, Mike Riley wrote: > Pardon my ignorance, but why are you doing this? Lot's of applications are > delivered in packages other than where libraries they use are located.
>From the bug report: The putback for 6618343 resulted in the lofiadm(1M) including zlib.h in order to compress a file. It turns out that lofiadm is included in the SUNWcsu whereas zlib (and zlib.h) is delivered as part of SUNWzlib. This can cause problems if lofiadm is used to compress a file on a system that doesn't have SUNWzlib installed. So, in other words if libz isn't installed on the system the command will simply be killed with a rather unpleasant error. > What your change does here is move the code that resolves the symbol to > access the library into the application itself, when Solaris would have done > that for you. Also, you have now created a hard dependency on libz.so.1 > being in /usr/lib, as well as being named libz.so.1, where previously the > Makefile handled the name and Solaris found where it was located for you. Let me turn that around, how is this dependancy better or worse than <libz.h> being in /usr/include? And libz.h being named libz and not something else in the future? Both are public ARC'd interfaces (although I can't find their stability levels at the moment), their consumers will break the moment you start moving/renaming them. > In the gzip_compress() function you call die() if you can't locate the symbol > compress2() in the library, or if you can't find the library. I fail to see > how that is different from Solaris reporting the same info and not running > the program, unless it is that this routine is never invoked unless > compression is requested, in which case an uncompressed volume would never > see this error using your new code. The behavior is very different. Without this fix, lofiadm will die whether or not you requested compression or not with the following error message - ld.so.1: lofiadm: fatal: libz.so.1: open failed: No such file or directory zsh: killed lofiadm With this fix, lofiadm will error out only if compression is requested with the following error message - lofiadm: error locating /usr/lib/libz.so.1: No such file or directory I will let you decide which behavior you would rather see. > In a separate issue: > > Looking at the code I see that gzip_compress() is used in a table: > lofi_compress_table > > The only place that is ever called is line 610: > 610 (void) li->l_compress(uncompressed_seg, rbytes, > 611 compressed_seg + SEGHDR, &real_segsize, li->l_level); > > In gzip_compress() you are also returning either -1 or 0, depending on what > calling calling compress2() via compress2p returns. Yet in line 610 you are > throwing that result away. So the purpose of returning a 0 or -1 here is??? l_compress and l_decompress are both defined as lofi_compress_func_t's which returns an int. One decides to look at the return value whereas the other throws it away. So, returning an int is there for consistency. Alok
