[PATCH 2/4] perl.mak: introduce $(GIT_ROOT_DIR) to allow inclusion from other directories

[Matthieu Moy <Matthieu.Moy@imag.fr>]

perl.mak uses relative path, which is OK when called from the toplevel,
but won't be anymore if one includes it from elsewhere. It is now
possible to include the file using:

GIT_ROOT_DIR=<whatever>
include $(GIT_ROOT_DIR)/perl.mak

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
---
 perl.mak | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/perl.mak b/perl.mak
index 8bbeef3..a2b8717 100644
--- a/perl.mak
+++ b/perl.mak
@@ -1,5 +1,9 @@
 # Rules to build Git commands written in perl
 
+ifndef GIT_ROOT_DIR
+	GIT_ROOT_DIR = .
+endif
+
 ifndef PERL_PATH
 	PERL_PATH = /usr/bin/perl
 endif
@@ -11,12 +15,11 @@ NO_PERL = NoThanks
 endif
 
 ifndef NO_PERL
-$(patsubst %.perl,%,$(SCRIPT_PERL)): perl/perl.mak
-
+$(patsubst %.perl,%,$(SCRIPT_PERL)): $(GIT_ROOT_DIR)/perl/perl.mak
 
-$(patsubst %.perl,%,$(SCRIPT_PERL)): % : %.perl GIT-VERSION-FILE
+$(patsubst %.perl,%,$(SCRIPT_PERL)): % : %.perl $(GIT_ROOT_DIR)/GIT-VERSION-FILE
 	$(QUIET_GEN)$(RM) $@ $@+ && \
-	INSTLIBDIR=`MAKEFLAGS= $(MAKE) -C perl -s --no-print-directory instlibdir` && \
+	INSTLIBDIR=`MAKEFLAGS= $(MAKE) -C $(GIT_ROOT_DIR)/perl -s --no-print-directory instlibdir` && \
 	sed -e '1{' \
 	    -e '	s|#!.*perl|#!$(PERL_PATH_SQ)|' \
 	    -e '	h' \
-- 
1.8.1.2.526.gf51a757