tools/prost-build: update edition, remove clap

Clap is a big dependency, but we have very simple needs. We remove it
to reduce the compile time.

Author: benma

messages/CMakeLists.txt

@@ -33,7 +33,7 @@ add_custom_command(
   # Using prost-build the normal way as part of build.rs does not work due to a cargo bug:
   # https://github.com/danburkert/prost/issues/344#issuecomment-650721245
   COMMAND
-    ${PROST_BUILD} --messages-dir=${CMAKE_CURRENT_SOURCE_DIR} --out-dir=${CMAKE_SOURCE_DIR}/src/rust/bitbox02-rust/src/
+    ${PROST_BUILD} ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_SOURCE_DIR}/src/rust/bitbox02-rust/src/
 )
 
 add_custom_target(

tools/prost-build/Cargo.lock

@@ -16,12 +16,9 @@
 name = "prost-build"
 version = "0.1.0"
 authors = ["Shift Crypto AG <[email protected]>"]
-edition = "2018"
+edition = "2021"
 license = "Apache-2.0"
 
-[dependencies]
-clap = "3.0.0-beta.1"
-
 [dependencies.prost-build]
 # keep version in sync with src/rust/bitbox02-rust/Cargo.toml
 version = "0.7.0"

tools/prost-build/Cargo.toml

@@ -12,21 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use clap::Clap;
-
-#[derive(Clap)]
-struct Opts {
-    #[clap(long)]
-    messages_dir: String,
-    #[clap(long)]
-    out_dir: String,
-}
+use std::env;
 
 fn main() {
-    let opts: Opts = Opts::parse();
+    let args: Vec<String> = env::args().collect();
+    let messages_dir = &args[1];
+    let out_dir = &args[2];
     let mut config = prost_build::Config::new();
-    config.out_dir(opts.out_dir);
+    config.out_dir(out_dir);
     config
-        .compile_protos(&["hww.proto", "backup.proto"], &[&opts.messages_dir])
+        .compile_protos(&["hww.proto", "backup.proto"], &[messages_dir])
         .unwrap();
 }