build: Add DESTDIR to make

Add the variable DESTDIR that allows a user to install into
a directory that will later be moved to another host. This
facilitates the creation of distribution packages.

  make DESTDIR=/tmp/build prefix=/usr install

Will install the program files into /tmp/build/usr/..
but the program will expect to find itself in the /usr/..
directories.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 10 insertions, 8 deletions

diff --git a/Documentation/Makefile b/Documentation/Makefile
index d161703..b7c17e7 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -12,7 +12,7 @@ else
   Q = @
   print_asciidoc =              echo '      ASCIIDOC            '`basename $@`;
   print_xsltproc =              echo '      XSLTPROC            '`basename $@`;
-  print_install =               echo '      INSTALL             '`basename $1`' to      '$2;
+  print_install =               echo '      INSTALL             '`basename $1`' to      $(DESTDIR_SQ)'$2;
   hide_xsltproc_output = 2> /dev/null
 endif
 
@@ -69,21 +69,23 @@ MAN5 = $(patsubst %.5.txt,$(obj)/%.5, ${TEXT5})
 
 all: $(MAN1) $(MAN5)
 
+# Need to find out how to export a macro instead of
+# copying this from the main Makefile.
 define do_install
-        $(print_install)                        \
-        if [ ! -d $2 ]; then                    \
-                $(INSTALL) -d -m 755 $2 ;       \
-        fi;                                     \
-        $(INSTALL) $1 $2;
+        $(print_install)                                \
+        if [ ! -d '$(DESTDIR_SQ)$2' ]; then             \
+                $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
+        fi;                                             \
+        $(INSTALL) $1 '$(DESTDIR_SQ)$2'
 endef
 
 MAN1_INSTALL = $(MAN1:%.1=%.1.install)
 MAN5_INSTALL = $(MAN5:%.5=%.5.install)
 
 $(MAN1_INSTALL): %.1.install : %.1 force
-        $(Q)$(call do_install, $<, '$(man_dir_SQ)/man1')
+        $(Q)$(call do_install,$<,$(man_dir_SQ)/man1)
 $(MAN5_INSTALL): %.5.install : %.5 force
-        $(Q)$(call do_install, $<, '$(man_dir_SQ)/man5')
+        $(Q)$(call do_install,$<,$(man_dir_SQ)/man5)
 
 install: $(MAN1_INSTALL) $(MAN5_INSTALL)