1 files changed, 50 insertions, 0 deletions
diff --git a/toolkit/components/uniffi-js/UniFFIRust.h b/toolkit/components/uniffi-js/UniFFIRust.h
new file mode 100644
index 0000000000..bdda442551
--- /dev/null
+++ b/toolkit/components/uniffi-js/UniFFIRust.h
@@ -0,0 +1,50 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_UniFFIRust_h
+#define mozilla_UniFFIRust_h
+
+#include <stdint.h>
+
+namespace mozilla::uniffi {
+
+// Low-level Rust structs for UniFFI
+
+// RustCallStatus.code values
+constexpr int8_t RUST_CALL_SUCCESS = 0;
+constexpr int8_t RUST_CALL_ERROR = 1;
+constexpr int8_t RUST_CALL_INTERNAL_ERROR = 2;
+
+// Return values for callback interfaces (See
+// https://github.com/mozilla/uniffi-rs/blob/main/uniffi/src/ffi/foreigncallbacks.rs
+// for details)
+constexpr int8_t CALLBACK_INTERFACE_SUCCESS = 1;
+constexpr int8_t CALLBACK_INTERFACE_INTERNAL_ERROR = -1;
+constexpr int8_t CALLBACK_INTERFACE_ERROR = -2;
+
+// structs/functions from UniFFI
+extern "C" {
+struct RustBuffer {
+  int32_t capacity;
+  int32_t len;
+  uint8_t* data;
+};
+
+struct RustCallStatus {
+  int8_t code;
+  RustBuffer error_buf;
+};
+
+typedef int (*ForeignCallback)(uint64_t handle, uint32_t method,
+                               RustBuffer args, RustBuffer* buf_ptr);
+
+RustBuffer uniffi_rustbuffer_alloc(int32_t size, RustCallStatus* call_status);
+void uniffi_rustbuffer_free(RustBuffer buf, RustCallStatus* call_status);
+}
+
+}  // namespace mozilla::uniffi
+
+#endif /* mozilla_UniFFIRust_h */