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+/* 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/. */
+
+#![allow(non_snake_case)]
+
+//! This crate bridges the WebExtension storage area interfaces in Firefox
+//! Desktop to the extension storage Rust component in Application Services.
+//!
+//! ## How are the WebExtension storage APIs implemented in Firefox?
+//!
+//! There are three storage APIs available for WebExtensions:
+//! `storage.local`, which is stored locally in an IndexedDB database and never
+//! synced to other devices, `storage.sync`, which is stored in a local SQLite
+//! database and synced to all devices signed in to the same Firefox Account,
+//! and `storage.managed`, which is provisioned in a native manifest and
+//! read-only.
+//!
+//! * `storage.local` is implemented in `ExtensionStorageIDB.jsm`.
+//! * `storage.sync` is implemented in a Rust component, `webext_storage`. This
+//!   Rust component is vendored in m-c, and exposed to JavaScript via an XPCOM
+//!   API in `webext_storage_bridge` (this crate). Eventually, we'll change
+//!   `ExtensionStorageSync.jsm` to call the XPCOM API instead of using the
+//!   old Kinto storage adapter.
+//! * `storage.managed` is implemented directly in `parent/ext-storage.js`.
+//!
+//! `webext_storage_bridge` implements the `mozIExtensionStorageArea`
+//! (and, eventually, `mozIBridgedSyncEngine`) interface for `storage.sync`. The
+//! implementation is in `area::StorageSyncArea`, and is backed by the
+//! `webext_storage` component.
+
+#[macro_use]
+extern crate cstr;
+#[macro_use]
+extern crate xpcom;
+
+mod area;
+mod error;
+mod punt;
+mod store;
+
+use nserror::{nsresult, NS_OK};
+use xpcom::{interfaces::mozIExtensionStorageArea, RefPtr};
+
+use crate::area::StorageSyncArea;
+
+/// The constructor for a `storage.sync` area. This uses C linkage so that it
+/// can be called from C++. See `ExtensionStorageComponents.h` for the C++
+/// constructor that's passed to the component manager.
+///
+/// # Safety
+///
+/// This function is unsafe because it dereferences `result`.
+#[no_mangle]
+pub unsafe extern "C" fn NS_NewExtensionStorageSyncArea(
+    result: *mut *const mozIExtensionStorageArea,
+) -> nsresult {
+    match StorageSyncArea::new() {
+        Ok(bridge) => {
+            RefPtr::new(bridge.coerce::<mozIExtensionStorageArea>()).forget(&mut *result);
+            NS_OK
+        }
+        Err(err) => err.into(),
+    }
+}