Re: [patch] Avoid some of the sc_ rules to freeze

[Pádraig Brady]

On 22/02/10 15:08, jema...@gnu.org wrote:

    Would it be better to just add /dev/null as a parameter to grep?
    I.E. like:

            @grep -nE 'error \(EXIT_SUCCESS,'                           \
                $$($(VC_LIST_EXCEPT) /dev/null | grep -E '\.[chly]$$')&&        
\
              { echo '$(ME): found error (EXIT_SUCCESS' 1>&2; exit 1; } || :


The grep freezing is the top-level one, not the one matching the
.[chly] files.  It would be:

  @grep -nE 'error \(EXIT_SUCCESS,'                                    \
     $$($(VC_LIST_EXCEPT) | grep -E '\.[chly]$$')<  /dev/null&&       \
        { echo '$(ME): found error (EXIT_SUCCESS' 1>&2; exit 1; } || :

But consider the sc_ rules that are searching files not containing a
given pattern:

sc_program_name:
        files=$$(grep -l '^main *(' $$($(VC_LIST_EXCEPT) | grep '\.c$$'));      
\
        grep -LE 'set_program_name *\(m?argv\[0\]\);' $$files<  /dev/null    \
              | grep .&&                                                        
\
          { echo '$(ME): the above files do not call set_program_name'          
\
                1>&2; exit 1; } || :;

In that case the grep uses the -L option, and the effect of using the
redirection from /dev/null is:

$ make sc_program_name
program_name
(standard input)

Yes that's problematic

I suggest to use the following solution that works properly in all
cases while avoiding the code duplication (in the spirit of
_prohibit_regexp):

define _sc_maybe_matching_files
   dummy=; : so we do not need a semicolon before each use;             \
   test "x$$re" != x || { echo '$(ME): re not defined' 1>&2; exit 1; }; \
   if test -n "$$matching"; then matching='yes'; fi        \
   files=$$($(VC_LIST_EXCEPT) | grep -E "$$fre");          \
   if test -n "$$files"; then                              \
     if test "$$matching" = "yes"; then                    \
        grep -nE "$$re" $$files&&                          \
           {echo "$(ME): $$msg" 1>&2; exit 1; } || :       \
     else                                                  \
        grep -LE "$$re" $$files | grep .&&                 \
           {echo "$(ME): $$msg" 1>&2; exit1: } || :        \
   else :;                                                 \
   fi
endef

define _sc_matching_files
   matching='yes'                                          \
   $(_sc_maybe_matching_files)
endef

define _sc_non_matching_files                             \
   matching='no'                                           \
   $(_sc_maybe_matching_files)
endef

sc_error_exit_success:
         @fre='\.[chly]$$'                                 \
         re='error \(EXIT_SUCCESS,'                        \
         msg='$(ME): found error (EXIT_SUCCESS'            \
           $(_sc_matching_files)

sc_program_name:
         @fre='\.c$$'                                      \
         re='set_program_name *\(m?argv\[0\]\);'           \
         msg='$(ME): the above files do not call set_program_name' \
           $(_sc_non_matching_files)

That refactoring looks good.

thanks,
Pádraig.