Makefile: replace bindgen with awk

Makefile

@@ -29,8 +29,6 @@ CFLAGS += -Ibuild/include
 .PHONY: all
 all: docs dj false fop hru intcmp mm npc rpn scrut str strcmp swab true
 
-# keep build/include until bindgen(1) has stdin support
-# https://github.com/rust-lang/rust-bindgen/issues/2703
 build:
 	mkdir -p build/bin build/docs build/include build/lib build/o build/test
 
@@ -77,10 +75,10 @@ build/o/libstrerror.rlib: build src/strerror.rs
 	$(RUSTC) $(RUSTFLAGS) --crate-type=lib -o $@ \
 		src/strerror.rs
 
-# bandage solution until bindgen(1) gets stdin support
 build/o/libsysexits.rlib: build build/include/sysexits.h
-	bindgen --default-macro-constant-type signed --use-core --formatter=none \
-		build/include/sysexits.h | $(RUSTC) $(RUSTFLAGS) --crate-type lib -o $@ -
+	<build/include/sysexits.h \
+		awk '{ print "pub const " $$2 ": i32 = " $$3 ";"; }' \
+		| $(RUSTC) $(RUSTFLAGS) --crate-type lib -o $@ -
 
 .PHONY: dj
 dj: build/bin/dj
@@ -139,7 +137,7 @@ build/bin/strcmp: src/strcmp.c build
 
 .PHONY: swab
 swab: build/bin/swab
-build/bin/swab: src/swab.rs build build/o/libsysexits.rlib
+build/bin/swab: src/swab.rs build rustlibs
 	$(RUSTC) $(RUSTFLAGS) --extern getopt=build/o/libgetopt.rlib \
 		--extern sysexits=build/o/libsysexits.rlib \
 		-o $@ src/swab.rs