Generate man pages with m4.

Allows substituting current version and release date.

Makefile

@@ -2,6 +2,7 @@
 
 all:
 	$(MAKE) -C src all
+	$(MAKE) -C doc/manpages all
 	@echo "***"
 	@echo "*** Build complete; use \"make check\" to run unit tests, \"make check-igr\" for"
 	@echo "*** integration tests, or \"make install\" to install."
@@ -22,3 +23,4 @@ install:
 
 clean:
 	$(MAKE) -C src clean
+	$(MAKE) -C doc/manpages clean

doc/manpages/Makefile

@@ -1,6 +1,11 @@
 include ../../mconfig
+include ../../src/version.conf
 
-install:
+all: generate
+
+generate: dinit.8 dinitctl.8 dinit-service.5 shutdown.8
+
+install: generate
 	mkdir -p "$(DESTDIR)$(MANDIR)/man8"
 	install -m644 dinit.8 dinitctl.8 "$(DESTDIR)$(MANDIR)/man8"
 	mkdir -p "$(DESTDIR)$(MANDIR)/man5"
@@ -10,3 +15,18 @@ ifeq ($(BUILD_SHUTDOWN),yes)
 	ln -f "$(DESTDIR)$(MANDIR)/man8/shutdown.8" "$(DESTDIR)$(MANDIR)/man8/halt.8" 
 	ln -f "$(DESTDIR)$(MANDIR)/man8/shutdown.8" "$(DESTDIR)$(MANDIR)/man8/reboot.8" 
 endif
+
+clean:
+	rm -f dinit.8 dinitctl.8 dinit-service.5 shutdown.8
+
+dinit.8: dinit.8.m4
+	m4 -DVERSION=$(VERSION) -DMONTH=$(MONTH) -DYEAR=$(YEAR) dinit.8.m4 > dinit.8
+
+dinitctl.8: dinitctl.8.m4
+	m4 -DVERSION=$(VERSION) -DMONTH=$(MONTH) -DYEAR=$(YEAR) dinitctl.8.m4 > dinitctl.8
+
+dinit-service.5: dinit-service.5.m4
+	m4 -DVERSION=$(VERSION) -DMONTH=$(MONTH) -DYEAR=$(YEAR) dinit-service.5.m4 > dinit-service.5
+
+shutdown.8: shutdown.8.m4
+	m4 -DVERSION=$(VERSION) -DMONTH=$(MONTH) -DYEAR=$(YEAR) shutdown.8.m4 > shutdown.8

doc/manpages/dinit-service.5 → doc/manpages/dinit-service.5.m4

@@ -1,4 +1,5 @@
-.TH DINIT-SERVICE "5" "June 2019" "Dinit 0.5.2" "Dinit \- service management system"
+changequote(`@@@',`$$$')dnl
+@@@.TH DINIT-SERVICE "5" "$$$MONTH YEAR@@@" "Dinit $$$VERSION@@@" "Dinit \- service management system"
 .SH NAME
 Dinit service description files
 .\"
@@ -452,3 +453,4 @@ More examples are provided with the Dinit distribution.
 .\"
 .SH AUTHOR
 Dinit, and this manual, were written by Davin McCall.
+$$$dnl

doc/manpages/dinit.8 → doc/manpages/dinit.8.m4

@@ -1,4 +1,5 @@
-.TH DINIT "8" "June 2019" "Dinit 0.5.2" "Dinit \- service management system"
+changequote(`@@@',`$$$')dnl
+@@@.TH DINIT "8" "$$$MONTH YEAR@@@" "Dinit $$$VERSION@@@" "Dinit \- service management system"
 .SH NAME
 dinit \- supervise processes and manage services
 .\"
@@ -175,3 +176,4 @@ and exit Dinit; SIGQUIT exits Dinit immediately.
 .\"
 .SH AUTHOR
 Dinit, and this manual, were written by Davin McCall.
+$$$dnl

doc/manpages/dinitctl.8 → doc/manpages/dinitctl.8.m4

@@ -1,4 +1,5 @@
-.TH DINITCTL "8" "June 2019" "Dinit 0.5.2" "Dinit \- service management system"
+changequote(`@@@',`$$$')dnl
+@@@.TH DINITCTL "8" "$$$MONTH YEAR@@@" "Dinit $$$VERSION@@@" "Dinit \- service management system"
 .SH NAME
 dinitctl \- control services supervised by Dinit
 .\"
@@ -181,3 +182,4 @@ unless pinned.
 .\"
 .SH AUTHOR
 Dinit, and this manual, were written by Davin McCall.
+$$$dnl

doc/manpages/shutdown.8 → doc/manpages/shutdown.8.m4

@@ -1,4 +1,5 @@
-.TH SHUTDOWN "8" "June 2019" "Dinit 0.5.2" "Dinit \- service management system"
+changequote(`@@@',`$$$')dnl
+@@@.TH SHUTDOWN "8" "$$$MONTH YEAR@@@" "Dinit $$$VERSION@@@" "Dinit \- service management system"
 .SH NAME
 shutdown, halt, reboot \- system shutdown 
 .\"
@@ -58,3 +59,4 @@ system shutdown after it has rolled back services.
 .\"
 .SH AUTHOR
 Dinit, and this manual, were written by Davin McCall.
+$$$dnl

src/version.conf

@@ -0,0 +1,4 @@
+# Included from Makefiles.
+VERSION=0.5.2
+MONTH=June
+YEAR=2019