Makefile, getopt-rs: added getopt-rs library

Makefile

@@ -28,7 +28,7 @@ all: false fop intcmp scrut str strcmp true
 build:
 	# keep build/include until bindgen(1) has stdin support
 	# https://github.com/rust-lang/rust-bindgen/issues/2703
-	mkdir -p build/bin build/include build/o build/lib
+	mkdir -p build/bin build/include build/lib build/o build/test
 
 clean:
 	rm -rf build/ dist/
@@ -51,6 +51,7 @@ install: dist
 test: build
 	tests/cc-compat.sh
 	tests/posix-compat.sh
+	$(RUSTC) --test src/getopt-rs/lib.rs -o build/test/getopt
 
 sysexits: build
 	# bandage solution until bindgen(1) gets stdin support
@@ -62,11 +63,16 @@ sysexits: build
 			| sed 's/ /\n/g' | grep sysexits.h)" \
 		| $(RUSTC) $(RUSTCFLAGS) --crate-type lib -o build/o/libsysexits.rlib -
 
+libgetopt: src/getopt-rs/lib.rs
+	$(RUSTC) $(RUSTCFLAGS) --crate-type=lib --crate-name=getopt \
+		-o build/o/libgetopt.rlib src/lib.rs
+
 false: src/false.rs build
 	$(RUSTC) $(RUSTFLAGS) -o build/bin/false src/false.rs
 
-fop: src/fop.rs build sysexits
-	$(RUSTC) $(RUSTFLAGS) -o build/bin/fop src/fop.rs
+fop: src/fop.rs build libgetopt sysexits
+	$(RUSTC) $(RUSTFLAGS) --extern getopt=build/o/libgetopt.rlib \
+		-o build/bin/fop src/fop.rs
 
 intcmp: src/intcmp.c build
 	$(CC) $(CFLAGS) -o build/bin/intcmp src/intcmp.c