build: major rework of make targets

Signed-off-by: Cameron Nemo <[email protected]>

.gitignore

@@ -1,4 +1,3 @@
+*~
 *.o
-brillo
-brillo.1
-contrib/*brillo.policy
+/build

Makefile

@@ -1,17 +1,25 @@
 PROG := brillo
 DESC := Control the brightness of backlight and keyboard LED devices
 VENDOR := com.gitlab.CameronNemo
+VERSION := 1.4.7
 
+GOMD2MAN ?= go-md2man
+GROUP ?= video
+
+SYSCONFDIR ?= /etc
+AADIR ?= $(SYSCONFDIR)/apparmor.d
 PREFIX ?= /usr
+BINDIR ?= $(PREFIX)/bin
+MANDIR ?= $(PREFIX)/share/man/man1
+PKEDIR ?= $(PREFIX)/share/polkit-1/actions
+UDEVRULESDIR ?= $(PREFIX)/lib/udev/rules.d
 
-CFLAGS += -std=c99 -D_XOPEN_SOURCE=700 -pedantic -Wall -Werror -Wextra
-LDLIBS += -lm
+CFLAGS := $(CFLAGS) \
+	-std=c99 -D_XOPEN_SOURCE=700 -pedantic \
+	-Wall -Werror -Wextra \
+	-DPROG='"$(PROG)"' -DVERSION='"$(VERSION)"'
 
-BINDIR=$(DESTDIR)$(PREFIX)/bin
-MANDIR=$(DESTDIR)$(PREFIX)/share/man/man1
-PKEDIR=$(DESTDIR)$(PREFIX)/share/polkit-1/actions
-UDEVDIR=$(DESTDIR)$(PREFIX)/lib/udev/rules.d
-AADIR=$(DESTDIR)/etc/apparmor.d
+LDLIBS := $(LDLIBS) -lm
 
 SRC = \
 	src/vlog.c \
@@ -28,52 +36,60 @@ SRC = \
 
 OBJ = $(SRC:.c=.o)
 
-$(PROG): $(OBJ)
+build/$(PROG): $(OBJ)
+	mkdir -p build
 	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LDLIBS)
 
-install: $(PROG)
-	install -dZ -m 755 $(BINDIR)
-	install -DZ -m 755 ./$(PROG) -t $(BINDIR)
+install.bin: build/$(PROG)
+	install -Dm 0755 -t $(DESTDIR)$(BINDIR) $^
+
+build/$(VENDOR).$(PROG): contrib/apparmor.in
+	sed -e 's|@vendor@|$(VENDOR)|g' -e 's|@prog@|$(PROG)|g' $^ > $@
+
+install.apparmor: build/$(VENDOR).$(PROG)
+	install -d $(DESTDIR)$(AADIR)
+	install -m 0640 -t $(DESTDIR)$(AADIR) $^
+
+build/$(PROG).1: doc/man/brillo.1.md
+	$(GOMD2MAN) -in $^ -out $@
+
+install.man: build/$(PROG).1
+	install -d $(DESTDIR)$(MANDIR)
+	install -m 0644 -t $(DESTDIR)$(MANDIR) $^
 
-GOMD2MAN := $(shell which go-md2man 2>/dev/null)
+build/92-$(VENDOR).$(PROG).rules: contrib/udev.in
+	sed -e 's|@group@|$(GROUP)|g' $^ > $@
 
-$(PROG).1:
-ifndef GOMD2MAN
-	$(error "go-md2man not available")
-else
-	$(GOMD2MAN) -in doc/man/brillo.1.md -out $@
-endif
+install.udev: build/92-$(VENDOR).$(PROG).rules
+	install -d $(DESTDIR)$(UDEVRULESDIR)
+	install -m 00644 -t $(DESTDIR)$(UDEVRULESDIR) $^
 
-man: $(PROG).1
+install.common: install.apparmor install.man install.udev
 
-contrib/$(VENDOR).$(PROG).policy: contrib/polkit.in
-	sed -e 's|@bindir@|$(PREFIX)/bin|g' \
+install: install.bin install.common
+
+install.bin.setgid: build/$(PROG)
+	install -d $(DESTDIR)$(BINDIR)
+	install -m 2755 -g $(GROUP) -t $(DESTDIR)$(BINDIR) $^
+
+install.setgid: install.bin.setgid install.common
+
+build/$(VENDOR).$(PROG).policy: contrib/polkit.in
+	sed -e 's|@bindir@|$(BINDIR)|g' \
 	    -e 's|@prog@|$(PROG)|g' \
 	    -e 's|@vendor@|$(VENDOR)|g' \
 	    -e 's|@desc@|$(DESC)|g' \
 	    $^ > $@
 
-polkit: contrib/$(VENDOR).$(PROG).policy
-
-dist: $(PROG) man polkit
-
-install-dist: install dist
-	install -dZ -m 755 $(MANDIR) $(PKEDIR) $(UDEVDIR) $(AADIR) $(AADIR)/local
-	install -DZ -m 644 $(PROG).1 -t $(MANDIR)
-	install -DZ -m 644 contrib/$(VENDOR).$(PROG).policy -t $(PKEDIR)
-	install -DZ -m 644 contrib/90-brillo.rules -t $(UDEVDIR)
-	install -DZ -m 644 contrib/bin.brillo -t $(AADIR)
-	install -DZ -m 644 contrib/local/bin.brillo -t $(AADIR)/local
+install.polkit: build/$(VENDOR).$(PROG).policy
+	install -d $(DESTDIR)$(PKEDIR)
+	install -m 0640 -t $(DESTDIR)$(PKEDIR) $^
 
-uninstall:
-	rm -f $(BINDIR)/$(PROG)
+dist:
 
-uninstall-dist:
-	rm -f $(MANDIR)/$(PROG).1
-	rm -f $(PKEDIR)/$(VENDOR).$(PROG).policy
-	rm -f $(UDEVDIR)/90-brillo.rules
+install-dist: install.bin install.common install.polkit
 
 clean:
-	rm -vfr *~ $(PROG) $(PROG).1 $(OBJ) contrib/$(VENDOR).$(PROG).policy
+	rm -rfv -- *~ $(OBJ) build
 
-.PHONY: install uninstall polkit dist install-dist uninstall-dist man clean
+.PHONY: install.bin install.apparmor install.man install.udev install.common install install.setgid install.polkit dist install-dist clean

README.md

@@ -17,21 +17,46 @@ For detailed usage, please refer to the [man page](doc/man/brillo.1.md).
 Installation
 ------------
 
-To build the binary `brillo` and install it:
+Building the manpage requires `go-md2man`.
 
-    make
-    sudo make install
+To build and install the binary, manpage, and udev rule:
 
-A full install, including the man page, polkit action, udev rule, and apparmor
-profile in addition to the binary:
+```
+$ make
+# make install
+```
 
-    make dist
-    sudo make install-dist
+Users in the configured group (`video` by default) will be able to adjust
+the brightness.
+An alternative group can be configured using the `GROUP` variable:
 
-> Note: the Makefile uses the `PREFIX` and `DESTDIR` variables to compose the
-> installation path. If set, they should be consistent for each make target.
+```
+# make install GROUP=_brillo
+```
 
-Unpriveleged Access
+If you would prefer to allow any user, regardless of group, to change the
+brightness, you may install the binary as `setgid`:
+
+```
+# make install.setgid GROUP=_brillo
+```
+
+To additionally install the apparmor profile:
+
+```
+# make install.apparmor
+```
+
+To additionally install the polkit rule:
+
+```
+# make install.polkit
+```
+
+> Note: the `install*` targets use the `PREFIX` and `DESTDIR` variables to
+>       compose the installation path and generate configuration files.
+
+Unprivileged Access
 -------------------
 
 ### polkit
@@ -40,17 +65,21 @@ Active sessions can invoke `brillo` via `pkexec` to escalate priveleges.
 
 Examples:
 
-    pkexec /usr/bin/brillo -O
-    pkexec /usr/bin/brillo -A 5
+```
+$ pkexec /usr/bin/brillo -O
+$ pkexec /usr/bin/brillo -A 5
+```
 
 > Note: this requires polkitd and (e)logind or ConsoleKit.
 
 ### udev
 
 `brillo`'s udev rule grants necessary permissions to the `video` group for
-backlight devices and to the `input` group for keyboard LED devices.
+backlight and keyboard LED devices.
 
-Any user in these groups can modify values directly.
+Users in these groups can modify values directly.
+Alternately, the binary may be installed as `setgid` so that any user may
+change the brightness.
 
 > Note: in this mode, stored brightness and minimum cap files will be in
 > the user's cache home (typically "~/.cache").
@@ -70,7 +99,7 @@ correction for external monitors.
 Copyright
 ---------
 
-Copyright (C) 2018 Cameron Nemo, 2014 Fredrik Haikarainen
+Copyright (C) 2018-2019 Cameron Nemo, 2014 Fredrik Haikarainen
 
 This is free software, see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE

contrib/apparmor.in

@@ -0,0 +1,25 @@
+# vim:syntax=apparmor
+
+#include <tunables/global>
+
+profile @vendor@.@prog@ /{,usr/}{,local/}bin/@prog@ {
+  #include <abstractions/base>
+
+  capability dac_override,
+  capability dac_read_search,
+
+  /{,usr/}{,local/}bin/@prog@ mixr,
+  /var/cache/@prog@ rw,
+  /var/cache/@prog@/** rwk,
+
+  # unpriveleged mode
+  owner @{HOME}/.cache/@prog@ rw,
+  owner @{HOME}/.cache/@prog@/** rwk,
+
+  /sys/class/{backlight,leds}/ r,
+  /sys/devices/**/brightness rwk,
+  /sys/devices/**/max_brightness r,
+
+  # Site-specific additions and overrides. See local/README for details.
+  #include if exists <local/@vendor@.@prog@>
+}

contrib/udev.in

@@ -0,0 +1,4 @@
+ACTION=="add", SUBSYSTEM=="backlight", RUN+="/bin/chgrp @group@ /sys/class/backlight/%k/brightness"
+ACTION=="add", SUBSYSTEM=="backlight", RUN+="/bin/chmod g+w /sys/class/backlight/%k/brightness"
+ACTION=="add", SUBSYSTEM=="leds", RUN+="/bin/chgrp @group@ /sys/class/leds/%k/brightness"
+ACTION=="add", SUBSYSTEM=="leds", RUN+="/bin/chmod g+w /sys/class/leds/%k/brightness"

src/info.c

@@ -74,7 +74,7 @@ bool info_print(LIGHT_OP_MODE op, char *prefix, bool exec)
  **/
 void info_print_version()
 {
-	printf("%s %s\n", LIGHT_PROG, LIGHT_VER);
+	printf("%s %s\n", PROG, VERSION);
 }
 
 /**
@@ -84,6 +84,6 @@ void info_print_version()
  **/
 void *info_print_help()
 {
-	printf("Usage: %s [options] [operation [value]]\n", LIGHT_PROG);
+	printf("Usage: %s [options] [operation [value]]\n", PROG);
 	return NULL;
 }

src/init.c

@@ -45,9 +45,9 @@ static char *init_cache(const char * const tgt)
 
 	if ((geteuid() == 0 && (env = "/var/cache")) || 
 	    (env = getenv("XDG_CACHE_HOME")))
-		dirfmt = "%s/" LIGHT_PROG;
+		dirfmt = "%s/" PROG;
 	else if ((env = getenv("HOME")))
-		dirfmt = "%s/.cache/" LIGHT_PROG;
+		dirfmt = "%s/.cache/" PROG;
 
 	if (!env) {
 		vlog_err("XDG/HOME env vars not set, failed to init cache");

src/light.h

@@ -6,9 +6,6 @@
 #include <stdlib.h>
 #include <stdint.h>
 
-#define LIGHT_PROG "brillo"
-#define LIGHT_VER "1.4.6"
-
 typedef enum LIGHT_FIELD {
 	LIGHT_FIELD_UNSET = 0,
 	LIGHT_BRIGHTNESS,