update rust_builder

rust_builder/cargokit/build_tool/lib/src/environment.dart

@@ -0,0 +1,68 @@
+/// This is copied from Cargokit (which is the official way to use it currently)
+/// Details: https://fzyzcjy.github.io/flutter_rust_bridge/manual/integrate/builtin
+
+import 'dart:io';
+
+extension on String {
+  String resolveSymlink() => File(this).resolveSymbolicLinksSync();
+}
+
+class Environment {
+  /// Current build configuration (debug or release).
+  static String get configuration =>
+      _getEnv("CARGOKIT_CONFIGURATION").toLowerCase();
+
+  static bool get isDebug => configuration == 'debug';
+  static bool get isRelease => configuration == 'release';
+
+  /// Temporary directory where Rust build artifacts are placed.
+  static String get targetTempDir => _getEnv("CARGOKIT_TARGET_TEMP_DIR");
+
+  /// Final output directory where the build artifacts are placed.
+  static String get outputDir => _getEnvPath('CARGOKIT_OUTPUT_DIR');
+
+  /// Path to the crate manifest (containing Cargo.toml).
+  static String get manifestDir => _getEnvPath('CARGOKIT_MANIFEST_DIR');
+
+  /// Directory inside root project. Not necessarily root folder. Symlinks are
+  /// not resolved on purpose.
+  static String get rootProjectDir => _getEnv('CARGOKIT_ROOT_PROJECT_DIR');
+
+  // Pod
+
+  /// Platform name (macosx, iphoneos, iphonesimulator).
+  static String get darwinPlatformName =>
+      _getEnv("CARGOKIT_DARWIN_PLATFORM_NAME");
+
+  /// List of architectures to build for (arm64, armv7, x86_64).
+  static List<String> get darwinArchs =>
+      _getEnv("CARGOKIT_DARWIN_ARCHS").split(' ');
+
+  // Gradle
+  static String get minSdkVersion => _getEnv("CARGOKIT_MIN_SDK_VERSION");
+  static String get ndkVersion => _getEnv("CARGOKIT_NDK_VERSION");
+  static String get sdkPath => _getEnvPath("CARGOKIT_SDK_DIR");
+  static String get javaHome => _getEnvPath("CARGOKIT_JAVA_HOME");
+  static List<String> get targetPlatforms =>
+      _getEnv("CARGOKIT_TARGET_PLATFORMS").split(',');
+
+  // CMAKE
+  static String get targetPlatform => _getEnv("CARGOKIT_TARGET_PLATFORM");
+
+  static String _getEnv(String key) {
+    final res = Platform.environment[key];
+    if (res == null) {
+      throw Exception("Missing environment variable $key");
+    }
+    return res;
+  }
+
+  static String _getEnvPath(String key) {
+    final res = _getEnv(key);
+    if (Directory(res).existsSync()) {
+      return res.resolveSymlink();
+    } else {
+      return res;
+    }
+  }
+}