Update build system

.gitignore

@@ -1,4 +1,3 @@
 /.rust/
 /doc/
-/rust-openssl
-/rust-openssl.dSYM/
+/build/

Makefile

@@ -1,15 +1,30 @@
-RUSTPKG ?= rustpkg
-RUSTC ?= rustc
-RUST_FLAGS ?= -Z debug-info -O
+RUSTC = rustc
+BUILDDIR = build
+RUSTFLAGS = -O -Z debug-info
 
-all:
-	$(RUSTPKG) $(RUST_FLAGS) install
+OPENSSL_LIB = lib.rs
+OPENSSL = $(BUILDDIR)/$(shell $(RUSTC) --crate-file-name $(OPENSSL_LIB))
+OPENSSL_TEST = $(BUILDDIR)/$(shell $(RUSTC) --test --crate-file-name $(OPENSSL_LIB))
 
-test:
-	$(RUSTC) $(RUST_FLAGS) --test lib.rs
-	./rust-openssl
+all: $(OPENSSL)
 
-.PHONY: test
+-include $(BUILDDIR)/openssl.d
+-include $(BUILDDIR)/openssl_test.d
+
+$(BUILDDIR):
+	mkdir -p $@
+
+$(OPENSSL): $(OPENSSL_LIB) | $(BUILDDIR)
+	$(RUSTC) $(RUSTFLAGS) --dep-info $(@D)/openssl.d --out-dir $(@D) $<
+
+check: $(OPENSSL_TEST)
+	$<
+
+$(OPENSSL_TEST): $(OPENSSL_LIB) | $(BUILDDIR)
+	$(RUSTC) $(RUSTFLAGS) --test --dep-info $(@D)/openssl_test.d \
+		--out-dir $(@D) $<
 
 clean:
-	rm -rf .rust rust-openssl rust-openssl.dSYM
+	rm -rf $(BUILDDIR)
+
+.PHONY: all check clean