1 files changed, 127 insertions, 0 deletions
diff --git a/toolkit/components/osfile/modules/osfile_native.jsm b/toolkit/components/osfile/modules/osfile_native.jsm
new file mode 100644
index 0000000000..5534887510
--- /dev/null
+++ b/toolkit/components/osfile/modules/osfile_native.jsm
@@ -0,0 +1,127 @@
+/* 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/. */
+
+/**
+ * Native (xpcom) implementation of key OS.File functions
+ */
+
+"use strict";
+
+var EXPORTED_SYMBOLS = ["read", "writeAtomic"];
+
+var { Constants } = ChromeUtils.import(
+  "resource://gre/modules/osfile/osfile_shared_allthreads.jsm"
+);
+
+var SysAll;
+if (Constants.Win) {
+  SysAll = ChromeUtils.import(
+    "resource://gre/modules/osfile/osfile_win_allthreads.jsm"
+  );
+} else if (Constants.libc) {
+  SysAll = ChromeUtils.import(
+    "resource://gre/modules/osfile/osfile_unix_allthreads.jsm"
+  );
+} else {
+  throw new Error("I am neither under Windows nor under a Posix system");
+}
+var { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+
+const lazy = {};
+
+/**
+ * The native service holding the implementation of the functions.
+ */
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "Internals",
+  "@mozilla.org/toolkit/osfile/native-internals;1",
+  "nsINativeOSFileInternalsService"
+);
+
+/**
+ * Native implementation of OS.File.read
+ *
+ * This implementation does not handle option |compression|.
+ */
+var read = function(path, options = {}) {
+  // Sanity check on types of options
+  if ("encoding" in options && typeof options.encoding != "string") {
+    return Promise.reject(new TypeError("Invalid type for option encoding"));
+  }
+  if ("compression" in options && typeof options.compression != "string") {
+    return Promise.reject(new TypeError("Invalid type for option compression"));
+  }
+  if ("bytes" in options && typeof options.bytes != "number") {
+    return Promise.reject(new TypeError("Invalid type for option bytes"));
+  }
+
+  return new Promise((resolve, reject) => {
+    lazy.Internals.read(
+      path,
+      options,
+      function onSuccess(success) {
+        success.QueryInterface(Ci.nsINativeOSFileResult);
+        if ("outExecutionDuration" in options) {
+          options.outExecutionDuration =
+            success.executionDurationMS + (options.outExecutionDuration || 0);
+        }
+        resolve(success.result);
+      },
+      function onError(operation, oserror) {
+        reject(new SysAll.Error(operation, oserror, path));
+      }
+    );
+  });
+};
+
+/**
+ * Native implementation of OS.File.writeAtomic.
+ * This should not be called when |buffer| is a view with some non-zero byte offset.
+ * Does not handle option |compression|.
+ */
+var writeAtomic = function(path, buffer, options = {}) {
+  // Sanity check on types of options - we check only the encoding, since
+  // the others are checked inside Internals.writeAtomic.
+  if ("encoding" in options && typeof options.encoding !== "string") {
+    return Promise.reject(new TypeError("Invalid type for option encoding"));
+  }
+
+  if (typeof buffer == "string") {
+    // Normalize buffer to a C buffer by encoding it
+    let encoding = options.encoding || "utf-8";
+    buffer = new TextEncoder(encoding).encode(buffer);
+  }
+
+  if (ArrayBuffer.isView(buffer)) {
+    // We need to throw an error if it's a buffer with some byte offset.
+    if ("byteOffset" in buffer && buffer.byteOffset > 0) {
+      return Promise.reject(
+        new Error("Invalid non-zero value of Typed Array byte offset")
+      );
+    }
+    buffer = buffer.buffer;
+  }
+
+  return new Promise((resolve, reject) => {
+    lazy.Internals.writeAtomic(
+      path,
+      buffer,
+      options,
+      function onSuccess(success) {
+        success.QueryInterface(Ci.nsINativeOSFileResult);
+        if ("outExecutionDuration" in options) {
+          options.outExecutionDuration =
+            success.executionDurationMS + (options.outExecutionDuration || 0);
+        }
+        resolve(success.result);
+      },
+      function onError(operation, oserror) {
+        reject(new SysAll.Error(operation, oserror, path));
+      }
+    );
+  });
+};