Compile and link 'libdome_key_event_source_simulator'

Turn this into a build dependency with Make.

Use Vladimir Matveev (https://stackoverflow.com/users/788207/vladimir-matveev)
and Shepmaster's
(https://stackoverflow.com/users/155423/shepmaster) answer on Stack
Overflow to sort out getting Cargo the search path for the static
library:
https://stackoverflow.com/questions/26246849/how-to-i-tell-rust-where-to-look-for-a-static-library/26254062#26254062

For some reason I wasn't able to get it to work by just putting the
library into `./target/debug/deps/`. I had to explicitly tell Cargo to
put that in the search path.

Also, we need to use `std::env` instead of the `env!` macro to get the
`PROFILE` environment variable, otherwise it won't be initialised at the
right time, as described in the Rust docs:

> Because these variables are not yet set when the build script is
> compiled, the above example using env! won't work and instead you'll
> need to retrieve the values when the build script is run

(https://doc.rust-lang.org/cargo/reference/environment-variables.html#environment-variables-cargo-sets-for-build-scripts)

2 files changed, 23 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index b4e76fa..67ae18e 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,13 @@ SOURCE_FILES = $(shell find src -type f -name '*.rs')
 
 LIB := target/debug/libdome_key_map.a
 
-$(LIB): $(SOURCE_FILES)
+DKESS_LIB_DEBUG := ~/Library/Developer/Xcode/DerivedData/dome_key_event_source_simulator-*/Build/Products/Debug/libdome_key_event_source_simulator.a
+DKESS_LOCAL_LIB_DEBUG := target/debug/deps/libdome_key_event_source_simulator.a
+
+.PHONY: build
+build: $(LIB)
+
+$(LIB): $(SOURCE_FILES) $(DKESS_LOCAL_LIB_DEBUG)
 	cargo build
 
 includer: clean $(LIB)
@@ -14,3 +20,9 @@ moder: moder.c $(LIB)
 .PHONY: clean
 clean:
 	rm -f includer moder
+
+$(DKESS_LIB_DEBUG):
+	$(MAKE) -C lib/dome_key_event_source_simulator $@
+
+$(DKESS_LOCAL_LIB_DEBUG): $(DKESS_LIB_DEBUG)
+	cp -a $< $@
diff --git a/build.rs b/build.rs
index d2a0b5d..8c883f4 100644
--- a/build.rs
+++ b/build.rs
@@ -1,5 +1,7 @@
 extern crate cbindgen;
 
+use std::env;
+
 use cbindgen::Language;
 
 fn main() {
@@ -15,4 +17,12 @@ fn main() {
         .generate()
         .expect("Unable to generate bindings")
         .write_to_file("dome_key_map.h");
+
+
+    // Link libdome_key_event_source_simulator.a
+    println!("cargo:rustc-link-lib=static=dome_key_event_source_simulator");
+    println!(
+        "cargo:rustc-link-search=native=./target/{profile}/deps",
+        profile=env::var("PROFILE").unwrap(),
+    );
 }