Use BINDIR, DATADIR and MANDIR in Makefile

Makefile

@@ -157,11 +157,11 @@ clean-coverage-run:
 install: install-dunst install-doc install-service
 
 install-dunst: dunst doc
-	install -Dm755 dunst ${DESTDIR}${PREFIX}/bin/dunst
+	install -Dm755 dunst ${DESTDIR}${BINDIR}/dunst
 	install -Dm644 docs/dunst.1 ${DESTDIR}${MANPREFIX}/man1/dunst.1
 
 install-doc:
-	install -Dm644 dunstrc ${DESTDIR}${PREFIX}/share/dunst/dunstrc
+	install -Dm644 dunstrc ${DESTDIR}${DATADIR}/dunst/dunstrc
 
 install-service: install-service-dbus
 install-service-dbus: service-dbus
@@ -173,9 +173,9 @@ install-service-systemd: service-systemd
 endif
 
 uninstall: uninstall-service
-	rm -f ${DESTDIR}${PREFIX}/bin/dunst
+	rm -f ${DESTDIR}${BINDIR}/dunst
 	rm -f ${DESTDIR}${MANPREFIX}/man1/dunst.1
-	rm -rf ${DESTDIR}${PREFIX}/share/dunst
+	rm -rf ${DESTDIR}${DATADIR}/dunst
 
 uninstall-service: uninstall-service-dbus
 uninstall-service-dbus:

README.md

@@ -38,7 +38,9 @@ sudo make install
 ### Make parameters
 
 - `PREFIX=<PATH>`: Set the prefix of the installation. (Default: `/usr/local`)
-- `MANPREFIX=<PATH>`: Set the prefix of the manpage. (Default: `${PREFIX}/share/man`)
+- `BINDIR=<PATH>`: Set the `dunst` executable's path (Default: `${PREFIX}/bin`)
+- `DATADIR=<PATH>`: Set the path for shared files. (Default: `${PREFIX}/share`)
+- `MANDIR=<PATH>`: Set the prefix of the manpage. (Default: `${DATADIR}/man`)
 - `SYSTEMD=(0|1)`: Enable/Disable the systemd unit. (Default: detected via `pkg-config`)
 - `SERVICEDIR_SYSTEMD=<PATH>`: The path to put the systemd user service file. Unused, if `SYSTEMD=0`. (Default: detected via `pkg-config`)
 - `SERVICEDIR_DBUS=<PATH>`: The path to put the dbus service file. (Default: detected via `pkg-config`)

config.mk

@@ -1,6 +1,9 @@
 # paths
 PREFIX ?= /usr/local
-MANPREFIX = ${PREFIX}/share/man
+BINDIR ?= ${PREFIX}/bin
+DATADIR ?= ${PREFIX}/share
+MANPREFIX ?= ${DATADIR}/man # around for backwards compatibility
+MANDIR ?= ${MANPREFIX}
 
 PKG_CONFIG ?= pkg-config