Add Linux impl

packages/celest_core/lib/src/secure_storage/secure_storage.linux.dart

@@ -0,0 +1,120 @@
+import 'dart:ffi';
+import 'dart:io';
+
+import 'package:celest_core/src/native/linux/glib.ffi.dart';
+import 'package:celest_core/src/native/linux/libsecret.ffi.dart';
+import 'package:celest_core/src/secure_storage/secure_storage_platform.vm.dart';
+import 'package:ffi/ffi.dart';
+
+final class SecureStoragePlatformLinux extends SecureStoragePlatform {
+  SecureStoragePlatformLinux({
+    required this.scope,
+  }) : super.base();
+
+  final String scope;
+
+  final _glibDylib = DynamicLibrary.open('libglib-2.0.so.0');
+  late final _glib = Glib(_glibDylib);
+
+  final _libSecretDylib = DynamicLibrary.open('libsecret-1.so.0');
+  late final _libSecret = Libsecret(_libSecretDylib);
+
+  late final _gStrHashPointer =
+      _glibDylib.lookup<NativeFunction<UnsignedInt Function(Pointer<Void>)>>(
+          'g_str_hash');
+
+  late final String _appName = () {
+    final application = _glib.g_application_get_default();
+    if (application == nullptr) {
+      return File('/proc/self/exe').resolveSymbolicLinksSync();
+    }
+    return _glib
+        .g_application_get_application_id(application)
+        .cast<Utf8>()
+        .toDartString();
+  }();
+
+  String _labelFor(String key) => '$scope/$key';
+  Pointer<SecretSchema> _schemaFor(Arena arena) => arena<SecretSchema>()
+    ..ref.name = _appName.toNativeUtf8(allocator: arena)
+    ..ref.flags = SecretSchemaFlags.SECRET_SCHEMA_NONE
+    ..ref.attributes[0].name = 'key'.toNativeUtf8(allocator: arena)
+    ..ref.attributes[0].type =
+        SecretSchemaAttributeType.SECRET_SCHEMA_ATTRIBUTE_STRING;
+
+  Pointer<GHashTable> _attributes({
+    required String key,
+    required Arena arena,
+  }) {
+    final hashTable = _glib.g_hash_table_new(_gStrHashPointer, nullptr);
+    _glib.g_hash_table_insert(
+      hashTable,
+      'key'.toNativeUtf8(allocator: arena).cast(),
+      key.toNativeUtf8(allocator: arena).cast(),
+    );
+    arena.onReleaseAll(() => _glib.g_hash_table_destroy(hashTable));
+    return hashTable;
+  }
+
+  @override
+  void clear() => using((arena) {
+        final schema = _schemaFor(arena);
+        final attributes = _attributes(key: '', arena: arena);
+        _libSecret.secret_password_clearv_sync(
+          schema,
+          attributes,
+          nullptr,
+          nullptr,
+        );
+      });
+
+  @override
+  String? delete(String key) => using((arena) {
+        final secret = read(key);
+        final schema = _schemaFor(arena);
+        final attributes = _attributes(key: key, arena: arena);
+        _libSecret.secret_password_clearv_sync(
+          schema,
+          attributes,
+          nullptr,
+          nullptr,
+        );
+        return secret;
+      });
+
+  @override
+  String? read(String key) => using((arena) {
+        final attributes = _attributes(key: key, arena: arena);
+        final schema = _schemaFor(arena);
+        final result = _libSecret.secret_password_lookupv_sync(
+          schema,
+          attributes,
+          nullptr,
+          nullptr,
+        );
+        if (result == nullptr) {
+          return null;
+        }
+        arena.onReleaseAll(() => _libSecret.secret_password_free(result));
+        return result.toDartString();
+      });
+
+  @override
+  String write(String key, String value) {
+    using((arena) {
+      final label = _labelFor(key).toNativeUtf8(allocator: arena);
+      final secret = value.toNativeUtf8(allocator: arena);
+      final attributes = _attributes(key: key, arena: arena);
+      _libSecret.secret_password_storev_sync(
+        _schemaFor(arena),
+        attributes,
+        nullptr,
+        label,
+        secret,
+        nullptr,
+        nullptr,
+      );
+    });
+    return value;
+  }
+}