Re: How to auto probe a directory

[Stefano Lattarini]

On 01/06/2013 09:45 AM, David Yu wrote:
> Hi guys:
>           I want my project auto probe the Makefile.am entry all
> directories, if a directory has Makefile.am,  I will create Makefile.in
> with automake.
>
Your best bet is to create a bootstrap script that prepares this
information for autoconf; something like (untested!):

  #!/bin/sh
  makefiles=`find . -name Makefile.am | sed 's/\.am/'`
  dirs=`echo "$makefiles" | sed 's,/Makefile$,,'
  for f in $makefiles; do echo "AC_CONFIG_FILES([$f])"; done > config-files.m4
  echo SUBDIRS = > subdirs.am
  for d in $dirs; do test "$d" = . || echo "SUBDIRS += $d"; done >> subdirs.am

and then, in configure.ac:

  m4_include([config-files.m4])

and in top-level Makefile.am:

  include $(top_srcdir)/subdirs.am

But is this extra complication really worth?  If you don't have too many
Makefile.am and subdirectories, I suggest you to list them explicitly in
AC_CONFIG_FILES ans SUBDIRS.  That will save you lot of headaches later
(among them, the need to explicitly re-run the above bootstrap by hand
whenever you add, remove or rename a Makefile.am-holding subdirectory).

>           After that, I will create Makefile with configure.
> 
> Here is my key codes of configure.in and Makefile.am
> ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> #configure.in
> DEVICE_COMPILE="shell find ./ -mindepth 2 -name Makefile.am | sed
> 's/Makefile.am/ /'"
> AC_SUBST(DEVICE_COMPILE)
> # probe the device modules
> for DEVICE_MODULES in `find device -mindepth 2 -name Makefile.am | sed
> 's/Makefile.am/Makefile/'`
> do
>        echo $DEVICE_MODULES
>         AC_CONFIG_FILES($DEVICE_MODULES)
> done
> AC_OUTPUT
>
This has no hope to work, since the arguments of AC_CONFIG_FILES must
be known by autoconf and automake at m4 runtime, not at shell runtime.

(True, you can run shell code from m4 as well -- with the 'm4_esyscmd'
and 'm4_esyscmd_s' autoconf-provided macros -- but doing so will
likely prove even more brittle than the "bootstrap script" approach
I suggested above).

> ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> #Makefile.am
> SUBDIRS = $(@DEVICE_COMPILE@)
>
Specifying the list of SUBDIRS as configure-time @subst@ has its share
of issues too; see:
<http://www.gnu.org/software/automake/manual/automake.html#Subdirectories-with-AC_005fSUBST>

> ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> 
> 1. I can probe the Makefile.am of every directory.
> 2. But I can't create Makefile.in with "automake --add-missing --copy
> --force-missing".
> 3. I added "AC_CONFIG_FILES(test/Makefile)" into configure.in, It can
> create Makefile.in in test/.
> 4. I removed  "AC_CONFIG_FILES(test/Makefile)" from configure.in, I can
> create Makefile with Makefile.in that is created in step 3.
> 
> I guess automake use "AC_CONFIG_FILES($DEVICE_MODULES)" create Makefile.in,
> but automake can't run the shell command, So "$DEVICE_MODULES" is NULL or
> invalid. While It can execute the shell command in the process of
> configure, so configure can create Makefile entry every directory that has
> Makefile.am, But there is not Makefile.in. then  I get a error :
> *config.status:
> error: cannot find input file: `test/Makefile.in'*
> *
> *
> My question is  how to use shell command in the process of automake.
> Other method is ok too.
> 
> My English is not good, I hope you can get it.
> 
> 
> David Yu
> Thanks
> 

HTH,
  Stefano