fix: set more NDK env vars + update examples (#27)

Fixes #26

Author: GregoryConrad

examples/dart_only/pubspec.yaml

@@ -10,11 +10,5 @@ dependencies:
   native_toolchain_rs: ^0.1.2+2
 
 dev_dependencies:
-  # TODO use released version
-  # ffigen: ^20.0.0-dev.0
-  ffigen:
-    git:
-      url: https://github.com/dart-lang/native
-      path: pkgs/ffigen
-      ref: 85fa542
+  ffigen: ^20.0.0-dev.1 # TODO switch to stable
   test: ^1.26.2

examples/dart_only/rust/Cargo.toml

@@ -3,8 +3,10 @@ name = "dart-only-example"
 edition = "2024"
 
 [lib]
-crate-type = ["staticlib", "cdylib"]
+# NOTE: also adding lib here so this can be consumed in the flutter example
+crate-type = ["staticlib", "cdylib", "lib"]
 
 [build-dependencies]
+bindgen = "0.72.1"
 cc = "1.2.39"
 cbindgen = "0.29.0"

examples/dart_only/rust/bindings.h

@@ -3,8 +3,9 @@ This file is automatically generated by build.rs; DO NOT MANUALLY EDIT!
 This header is designed to be consumed by ffigen over on the Dart side.
 */
 
+#include <stdarg.h>
+#include <stdbool.h>
 #include <stdint.h>
-
-extern int32_t c_add(int32_t a, int32_t b);
+#include <stdlib.h>
 
 int32_t rust_add(int32_t a, int32_t b);

examples/dart_only/rust/build.rs

@@ -1,8 +1,24 @@
-use std::env;
-
-use cbindgen::Language;
+use std::{env, path::PathBuf};
 
 fn main() {
+    create_c_to_rust_bindings();
+    build_c_library();
+    create_rust_to_dart_bindings();
+}
+
+fn create_c_to_rust_bindings() {
+    let bindings = bindgen::builder()
+        .header("c/c_add.h")
+        .generate()
+        .expect("Unable to generate bindings");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("Unable to write bindings");
+}
+
+fn build_c_library() {
     println!("cargo:rerun-if-changed=c/c_add.h");
     println!("cargo:rerun-if-changed=c/c_add.c");
 
@@ -12,14 +28,14 @@ fn main() {
         .compile("c_add");
 
     println!("cargo:rustc-link-lib=static=c_add");
+}
 
+fn create_rust_to_dart_bindings() {
     let crate_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
 
     cbindgen::Builder::new()
         .with_crate(crate_dir)
-        .with_language(Language::C)
-        .with_no_includes()
-        .with_sys_include("stdint.h")
+        .with_language(cbindgen::Language::C)
         .with_autogen_warning(
             "/*
 This file is automatically generated by build.rs; DO NOT MANUALLY EDIT!

examples/dart_only/rust/c/c_add.h

@@ -1,7 +1,10 @@
 #ifndef C_ADD_H
 #define C_ADD_H
 
+#include <stdarg.h>
+#include <stdbool.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 int32_t c_add(int32_t a, int32_t b);
 

examples/dart_only/rust/src/lib.rs

@@ -1,6 +1,5 @@
-unsafe extern "C" {
-    fn c_add(a: i32, b: i32) -> i32;
-}
+#![allow(warnings)]
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
 
 #[unsafe(no_mangle)]
 pub extern "C" fn rust_add(a: i32, b: i32) -> i32 {

examples/dart_only/tool/ffigen.dart

@@ -8,5 +8,5 @@ void main() {
     headers: Headers(entryPoints: [packageRoot.resolve('rust/bindings.h')]),
     output: Output(dartFile: packageRoot.resolve('lib/src/ffi.g.dart')),
     functions: Functions.includeSet({'rust_add'}),
-  ).generate(logger: null);
+  ).generate();
 }

examples/flutter/pubspec.yaml

@@ -12,13 +12,7 @@ dependencies:
   native_toolchain_rs: ^0.1.2+2
 
 dev_dependencies:
-  # TODO use released version
-  # ffigen: ^20.0.0-dev.0
-  ffigen:
-    git:
-      url: https://github.com/dart-lang/native
-      path: pkgs/ffigen
-      ref: 85fa542
+  ffigen: ^20.0.0-dev.1 # TODO switch to stable
   flutter_test:
     sdk: flutter
   integration_test:

examples/flutter/rust/Cargo.toml

@@ -5,5 +5,10 @@ edition = "2024"
 [lib]
 crate-type = ["staticlib", "cdylib"]
 
+[dependencies]
+# NOTE: this just verifies that cc/bindgen also work in flutter apps,
+# since dart-only-example uses cc/bindgen
+dart-only-example.path = "../../dart_only/rust"
+
 [build-dependencies]
 cbindgen = "0.29.0"

examples/flutter/rust/bindings.h

@@ -3,7 +3,10 @@ This file is automatically generated by build.rs; DO NOT MANUALLY EDIT!
 This header is designed to be consumed by ffigen over on the Dart side.
 */
 
+#include <stdarg.h>
+#include <stdbool.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 void reset_count(void);