Introduced automatic buildstamp generation for dynamic library version

Makefile.am

@@ -32,6 +32,15 @@ libinclude_HEADERS = \
 bin_PROGRAMS = \
 	xorriso/xorriso
 
+# Trying to create a build timestamp file
+#
+BUILT_SOURCES = xorriso/xorriso_buildstamp.h
+# phony targets get rebuilt every time
+.PHONY: xorriso/xorriso_buildstamp.h
+xorriso/xorriso_buildstamp.h:
+	date -u '+#define Xorriso_build_timestamP "%Y.%m.%d.%H%M%S"' >xorriso/xorriso_buildstamp.h
+	cat xorriso/xorriso_buildstamp.h
+
 xorriso_xorriso_CPPFLAGS = -Ilibisoburn
 xorriso_xorriso_CFLAGS = -DXorriso_with_maiN -DXorriso_with_regeX $(READLINE_DEF)
 xorriso_xorriso_LDADD = libisoburn/libisoburn.la -lisofs -lburn $(THREAD_LIBS)
@@ -56,7 +65,8 @@ install-exec-hook:
 	ln -s xorriso $(bindir)/xorrecord
 
 
-# Trying to create a build timestamp file
+# Outperformed by the .PHONY above. But still in for a few release cycles.
+# Trying to create a build timestamp file semi-manually
 #
 buildstamp:
 	date -u '+#define Xorriso_build_timestamP "%Y.%m.%d.%H%M%S"' >xorriso/xorriso_buildstamp.h
@@ -65,15 +75,8 @@ buildstamp:
 # For now   make buildstamped  has to be performed explicitely.
 buildstamped: buildstamp
 	make
-#
-# Processing of the "all:" rule happens too late.
-# How to create a dependency of xorriso.c on buildstamp ?
-# Not working:
-# Add xorriso_buildstamp.h to xorriso_xorriso_SOURCES and make it depend
-# on buildstamp. It runs. But at quite random occasions.
-# xorriso/xorriso_buildstamp.h: buildstamp
-#
-# all: buildstamp
+
+# ^^^ Outperformed by the .PHONY above ^^^
 
 
 ## Build test applications

xorriso/compile_xorriso.sh

@@ -76,9 +76,11 @@ libisofs="$libisofs $isofs"/util.o
 libisofs="$libisofs $isofs"/util_htable.o
 libisofs="$libisofs $isofs"/util_rbtree.o
 
-timestamp="$(date -u '+%Y.%m.%d.%H%M%S')"
+
 echo "Version timestamp :  $(sed -e 's/#define Xorriso_timestamP "//' -e 's/"$//' "$xorr"/xorriso_timestamp.h)"
-echo "Build timestamp   :  $timestamp"
+
+date -u '+#define Xorriso_build_timestamP "%Y.%m.%d.%H%M%S"' >"$xorr"/xorriso_buildstamp.h
+echo "Build timestamp   :  $(sed -e 's/#define Xorriso_build_timestamP "//' -e 's/"$//' "$xorr"/xorriso_buildstamp.h)"
 
 echo "compiling program $xorr/xorriso.c $static_opts $debug_opts $def_opts"
 cc -I. -DXorriso_with_maiN -DXorriso_with_regeX -DXorriso_with_readlinE \
@@ -88,8 +90,6 @@ cc -I. -DXorriso_with_maiN -DXorriso_with_regeX -DXorriso_with_readlinE \
   $def_opts \
   $largefile_opts \
   \
-  -DXorriso_build_timestamP='"'"$timestamp"'"' \
-  \
   -o "$xorr"/xorriso \
   \
   "$xorr"/xorriso.c \