[PATCH] new option: object-shortname

[Thomas Martitz]

This option is intended to be used in conjunction with subdir-objects and
Automake-time substitutions for included makefile fragments (%C%, %D%). It
suppresses the generation path components in object filenames.

It should equivalent to setting %C%_foo_SHORTNAME=foo, except it can work if
the makefile fragment is conditionally included, which improves the modularity
of Automake-using projects.

Example:
without object-shortname
  root/path/to/Makefile.am:
  bin_PROGRAMS += foo
  %C%_foo_CFLAGS = $(CFLAGS)

results in objects:
  root/path/to/root_path_to_foo-foo.o

with object-shortname the object filename is:
  root/path/to/foo-foo.o

And it allows the following in root/Makefile.am (not possible with 
foo_SHORTNAME=foo)
  if ENABLE_FOO
  include path/too/Makefile.am
  endif

* bin/automake.in: Handle new object-shortname option
* lib/Automake/Options.pm: Add the option

---
 bin/automake.in         | 13 +++++++++++++
 lib/Automake/Options.pm |  1 +
 2 files changed, 14 insertions(+)

diff --git a/bin/automake.in b/bin/automake.in
index eedc8bc..cea04c6 100644
--- a/bin/automake.in
+++ b/bin/automake.in
@@ -1691,6 +1691,19 @@ sub handle_single_transform
                # override.
 
 		my $dname = $derived;
+               if (option 'object-shortname') {
+                       # If object-shortname is enabled the object's filename 
shall not contain the parts
+                       # derived from its path (e.g. if %C% is used), but just 
the name of the object's target
+                       # e.g. instead of path_to_binary-object.o just 
binary-object
+                       my $dirname = dirname ($_file);
+                       if ($dirname ne ".") {
+                               my $canon_dirname = canonicalize ($dirname) . 
"_";
+                               # paranoid check: should never fail but ensure 
path prefix is part of the filename
+                               if (index ($derived, $canon_dirname) == 0) {
+                                       $dname = substr ($derived, length 
($canon_dirname));
+                               }
+                       }
+               }
                my $var = var ($derived . '_SHORTNAME');
                if ($var)
                {
diff --git a/lib/Automake/Options.pm b/lib/Automake/Options.pm
index 7d782c3..819c5ff 100644
--- a/lib/Automake/Options.pm
+++ b/lib/Automake/Options.pm
@@ -293,6 +293,7 @@ sub _is_valid_easy_option ($)
     silent-rules
     std-options
     subdir-objects
+    object-shortname
   );
 }
 
--
2.7.0