simplify Makefile

Due to consideration of POSIX compliance issues config.mk had
to be removed. Configuration variables can be overridden by
environment variables or specified via command line.

Additionally all pretty-printed messages were removed and
built-in rules are used. This also simplifies and purges
the Makefile.

Makefile

@@ -1,64 +1,45 @@
 # st - simple terminal
 # See LICENSE file for copyright and license details.
 
-include config.mk
+VERSION = 0.0
 
-SRC = st.c std.c pty.c
-OBJ = ${SRC:.c=.o}
+PREFIX = /usr/local
+MANDIR = $(PREFIX)/share/man
 
-all: options st std
+CFLAGS = -DVERSION=\"0.0\" -D_GNU_SOURCE
 
-options:
-	@echo st build options:
-	@echo "CFLAGS     = ${CFLAGS}"
-	@echo "LDFLAGS    = ${LDFLAGS}"
-	@echo "X11LDFLAGS = ${X11LDFLAGS}"
-	@echo "CC         = ${CC}"
-
-.c.o:
-	@echo CC $<
-	@${CC} -c ${CFLAGS} $<
-
-${OBJ}: config.mk
-
-st: st.o
-	@echo CC -o $@
-	@${CC} -o $@ $^ ${LDFLAGS} ${X11LDFLAGS}
-
-std: std.o pty.o
-	@echo CC -o $@
-	@${CC} -o $@ $^ ${LDFLAGS}
+all: st std
 
 clean:
-	@echo cleaning
-	@rm -f st std ${OBJ} st-${VERSION}.tar.gz
+	rm -f st std
+	rm -f st.o std.o
+	rm -f st-$(VERSION).tar.gz
 
 dist: clean
-	@echo creating dist tarball
-	@mkdir -p st-${VERSION}
-	@cp -R LICENSE Makefile README config.mk \
-		st.1 ${SRC} st-${VERSION}
-	@tar -cf st-${VERSION}.tar st-${VERSION}
-	@gzip st-${VERSION}.tar
-	@rm -rf st-${VERSION}
-
-install: all
-	@echo installing executable file to ${DESTDIR}${PREFIX}/bin
-	@mkdir -p ${DESTDIR}${PREFIX}/bin
-	@cp -f st ${DESTDIR}${PREFIX}/bin
-	@cp -f std ${DESTDIR}${PREFIX}/bin
-	@chmod 755 ${DESTDIR}${PREFIX}/bin/st
-	@echo installing manual page to ${DESTDIR}${MANPREFIX}/man1
-	@mkdir -p ${DESTDIR}${MANPREFIX}/man1
-	@sed "s/VERSION/${VERSION}/g" < st.1 > ${DESTDIR}${MANPREFIX}/man1/st.1
-	@chmod 644 ${DESTDIR}${MANPREFIX}/man1/st.1
-	@sed "s/VERSION/${VERSION}/g" < std.1 > ${DESTDIR}${MANPREFIX}/man1/std.1
-	@chmod 644 ${DESTDIR}${MANPREFIX}/man1/std.1
+	mkdir st-$(VERSION)
+	cp -f LICENSE README st-$(VERSION)
+	cp -f Makefile config.mk st-$(VERSION)
+	cp -f st.1 std.1 st-$(VERSION)
+	cp -f st.c std.c st-$(VERSION)
+	tar -czf st-$(VERSION).tar st-$(VERSION)
+	rm -rf st-$(VERSION)
+
+install:
+	mkdir -p $(DESTDIR)$(PREFIX)/bin
+	cp -f st $(DESTDIR)$(PREFIX)/bin
+	cp -f std $(DESTDIR)$(PREFIX)/bin
+	chmod 755 $(DESTDIR)$(PREFIX)/bin/st
+	chmod 755 $(DESTDIR)$(PREFIX)/bin/std
+	mkdir -p $(DESTDIR)$(MANDIR)/man1
+	sed 's/VERSION/$(VERSION)/g' < st.1 > $(DESTDIR)$(MANDIR)/man1/st.1
+	chmod 644 $(DESTDIR)$(MANDIR)/man1/st.1
+	sed 's/VERSION/$(VERSION)/g' < std.1 > $(DESTDIR)$(MANDIR)/man1/std.1
+	chmod 644 $(DESTDIR)$(MANDIR)/man1/std.1
 
 uninstall:
-	@echo removing executable file from ${DESTDIR}${PREFIX}/bin
-	@rm -f ${DESTDIR}${PREFIX}/bin/st
-	@echo removing manual page from ${DESTDIR}${MANPREFIX}/man1
-	@rm -f ${DESTDIR}${MANPREFIX}/man1/st.1
+	rm -f $(DESTDIR)$(PREFIX)/bin/st
+	rm -f $(DESTDIR)$(PREFIX)/bin/std
+	rm -f $(DESTDIR)$(MANDIR)/man1/st.1
+	rm -f $(DESTDIR)$(MANDIR)/man1/std.1
 
-.PHONY: all options clean dist install uninstall
+.PHONY: all clean dist install uninstall

config.mk

@@ -1,34 +0,0 @@
-# st version
-VERSION = 0.0
-
-# Customize below to fit your system
-
-# paths
-PREFIX = /usr/local
-MANPREFIX = ${PREFIX}/share/man
-
-X11INC = /usr/X11R6/include
-X11LIB = /usr/X11R6/lib
-
-# includes and libs
-INCS = -I. -I/usr/include -I${X11INC}
-LIBS = -L/usr/lib -lc
-X11LIBS =  -L${X11LIB} -lX11
-
-# glibc
-CPPFLAGS = -DVERSION=\"${VERSION}\" -D_GNU_SOURCE
-
-# flags
-#CPPFLAGS = -DVERSION=\"${VERSION}\"
-CFLAGS = -Os ${INCS} ${CPPFLAGS}
-LDFLAGS = -s ${LIBS}
-X11LDFLAGS = ${X11LIBS}
-#CFLAGS = -g -std=c99 -pedantic -Wall -O2 ${INCS} ${CPPFLAGS}
-#LDFLAGS = -g ${LIBS}
-
-# Solaris
-#CFLAGS = -fast ${INCS} -DVERSION=\"${VERSION}\"
-#LDFLAGS = ${LIBS}
-
-# compiler and linker
-CC = cc