Re: [Crash-utility] [RFC] makedumpfile, crash: LZO compression support

Hello Dave, From: Dave Anderson <anderson(a)redhat.com&gt; Subject: Re: [Crash-utility] [RFC] makedumpfile, crash: LZO compression support Date: Fri, 18 Nov 2011 10:20:26 -0500 (EST) > > > ----- Original Message ----- > >> > This could involve configure.c, but conceivably it could all be >> > done within the Makefile itself. For example, by entering >> > something >> > like "make compress=lzo2", and then adding this to the Makefile: >> > >> > ifneq ($(compress),) >> > ifeq ($(compress), lzo2) >> > LZOFLAG=-DLZO >> > LZOLIB=-llzo2 >> > endif >> > endif >> > >> > And then the diskdump.c compile line could use ${LZOFLAG}, and >> > the >> > gdb_merge stanza could include ${LZOLIB}. >> > >> >> Thanks for accepting the request and for detailed instructions. >> >> I'll reflect these configuration logic in the next patch. > > Actually, thinking more about it, I prefer the second solution: > >> On the other hand, the capability of dynamically adding an optional >> library could be a useful feature in general -- not only for LZO >> compression support, but for other things in the future. >> >> I'm thinking that we could allow the user create an "extralibs" file >> in the top-level directory, and then build_configure() in configure.c >> could read it and dynamically create the LDFLAGS= line in the Makefile. >> Currently LDFLAGS can only be modified manually, but the -static example >> hasn't worked for a long time, and should be removed. > > Then the only issue would be the extra -DLZO to be passed to diskdump.c. > Since any additional library would pretty much always require a conditional > function call or other library-specific reference, a general purpose > "extracflags" file could also be created and read by build_configure(), > and its contents appended to the Makefile's TARGET_CFLAGS line. > > With "extralibs" and "extracfiles", we would have a general-purpose > solution for adding optional libraries for use by both the top-level > crash sources as well as by extension modules that are built within > the extensions sub-directory. It would also negate the need to always > have to enter special "make ..." command every time -- instead just > create the "extralibs" and "extracflags" files, and it gets done > automatically. > Should I post the patch after this mechanism is prepared? And anyway I'm going to post the patch after makedumpfile accepts the corresponding patch.