Import Cargo, first steps towards porting to Rust 🦀

.gitignore

@@ -1 +1,3 @@
-build/
+/build
+/target
+Cargo.lock

Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "libfsm-rs"
+version = "0.1.0"
+authors = ["Kate F <kate@elide.org>"]
+edition = "2018"
+
+[lib]
+crate-type = ["staticlib"]
+path = "src/libfsm/lib.rs"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+

Makefile

@@ -92,7 +92,6 @@ INCDIR += include
 .include <obj.mk>
 .include <dep.mk>
 .include <ar.mk>
-.include <so.mk>
 .include <part.mk>
 .include <prog.mk>
 .include <mkdir.mk>
@@ -110,3 +109,22 @@ STAGE_BUILD := ${STAGE_BUILD:Nbin/cvtpcre}
 	grep FAIL ${BUILD}/tests/*/res*; [ $$? -ne 0 ]
 .endif
 
+.if !${CC:T:Memcc*}
+
+./target/debug/liblibfsm_rs.a:
+	cargo build
+
+test::
+	cargo test
+
+./target/debug/liblibfsm_rs.d: ./target/debug/liblibfsm_rs.a
+.if exists(./target/debug/liblibfsm_rs.d)
+.include "./target/debug/liblibfsm_rs.d"
+.endif
+
+${BUILD}/lib/libfsm.o: ./target/debug/liblibfsm_rs.a
+# hijacking LDRFLAGS here because the target only expects .o sources
+LDRFLAGS.libfsm += ./target/debug/liblibfsm_rs.a
+
+.endif
+

src/libfsm/fsm.c

@@ -22,6 +22,7 @@
 #include "internal.h"
 #include "capture.h"
 #include "endids.h"
+#include "libfsm_rs.h"
 
 void
 free_contents(struct fsm *fsm)
@@ -47,6 +48,9 @@ fsm_new(const struct fsm_options *opt)
 	static const struct fsm_options defaults;
 	struct fsm *new, f;
 
+	/* just to prove linking works */
+	fsm_noop();
+
 	if (opt == NULL) {
 		opt = &defaults;
 	}

src/libfsm/lib.rs

@@ -0,0 +1,12 @@
+// just here to prove linking works
+#[no_mangle]
+pub extern "C" fn fsm_noop() {
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn it_works() {
+        assert_eq!(2 + 2, 4);
+    }
+}

src/libfsm/libfsm.syms

@@ -126,3 +126,7 @@ fsm_capture_set_path
 fsm_capture_rebase_capture_id
 fsm_capture_alloc
 fsm_capture_dump
+
+# from rust
+fsm_noop
+

src/libfsm/libfsm_rs.h

@@ -0,0 +1,6 @@
+#ifndef LIBFSM_RS_H
+#define LIBFSM_RS_H
+
+void fsm_noop(void);
+
+#endif