[Crash-utility] RFC: crash extension module handling

[Dave Anderson]

Jeff Moyer wrote:
> Dave Anderson <anderson at redhat.com> writes:
> 
> 
>>Anyway, I've been tinkering with the extensions/Makefile to do such
>>a thing, and have a crude addition that does just that, although
>>it does the compile of all "new" C files every time whether they
>>need it or not -- via the additional "contrib" target:
>>
>>30c30
>>< all: link_defs $(OBJECTS)
>>---
>>
>>>all: link_defs $(OBJECTS) contrib
>>
>>43a44,50
>>
>>>contrib:
>>>	@for CFILE in `/bin/ls *.c | grep -v echo.c | grep -v dminfo.c
>>>| grep -v 
>>
>>sial.c`; do \
>>
>>>	   OUTPUT=`echo $$CFILE | cut -d. -f1`.so; \
>>>	   echo "gcc -nostartfiles -shared -rdynamic -o $$OUTPUT
>>>$$CFILE -fPIC 
>>
>>-D$(TARGET) $(TARGET_CFLAGS)"; \
>>
>>>	   gcc -nostartfiles -shared -rdynamic -o $$OUTPUT $$CFILE
>>>-fPIC -D$(TARGET) 
>>
>>$(TARGET_CFLAGS); \
>>
>>>        done
>>>
>>
>>It prevents the re-compilation of echo.c and dminfo.c, and of Luc
>>Chouinard's upcoming sial.c extension module.  (SIAL is an alternative
>>crash extension mechanism -- more on that when it's available...)
>>
>>Anyway, I've tried screwing around with the Makefile to use a generic
>>*.so target, using $@, $(basename ...) and so on, but I'm not a Makefile
>>master, and I cannot quite get it quite right, although I'm sure it can
>>be done.
>>
>>So if anybody out there can do it cleaner than the "contrib" target above,
>>I'd like to take a look.
> 
> 
> Try this.
> 
> Cheers,
> 
> Jeff
> 

Awesome! -- but see below...

> --- crash-4.0/extensions/Makefile.orig	2007-09-20 16:35:36.000000000 -0400
> +++ crash-4.0/extensions/Makefile	2007-09-20 16:35:42.000000000 -0400
> @@ -26,18 +26,15 @@
>  #  - create a compile stanza below, typically using "echo.so" as 
>  #    a base template.
>  # 
> +CONTRIB_SRC := $(wildcard *.c)
> +CONTRIB_SO := $(patsubst %.c,%.so,$(wildcard *.c))
>  
> -all: link_defs $(OBJECTS)
> +all: link_defs $(OBJECTS) $(CONTRIB_SO)
>  	
>  link_defs:
>  	@if [ ! -f defs.h ]; then \
>  	  ln -s ../defs.h; fi 
>  
> -echo.so: ../defs.h echo.c
> -	gcc -nostartfiles -shared -rdynamic -o echo.so echo.c -fPIC \
> -				 		-D$(TARGET) $(TARGET_CFLAGS)
> -
> -dminfo.so: ../defs.h dminfo.c
> -	gcc -nostartfiles -shared -rdynamic -o dminfo.so dminfo.c -fPIC \
> -				 		-D$(TARGET) $(TARGET_CFLAGS)
> -	
> +$(CONTRIB_SO): $(CONTRIB_SRC)
> +	gcc -nostartfiles -shared -rdynamic -o $@ $< -fPIC \
> +						-D$(TARGET) $(TARGET_CFLAGS)
> 

Question...

Can the above be done, but with one of the other specific
*.so targets still in place?  I ask because the sial.c
extension module *does* need a unique compile line (to
include an extra libsial.a library, some -I targets, etc.).

So I would still need to be able to exclude the sial.c file
from being built as above, as well as having its own target
in the Makefile.  And my earlier clumsy attempts kept "colliding"
with the other echo.so and dminfo.so targets.

Thanks,
   Dave