1 files changed, 103 insertions, 0 deletions
diff --git a/tools/addon-sdk-1.5/packages/api-utils/lib/preferences-service.js b/tools/addon-sdk-1.5/packages/api-utils/lib/preferences-service.js
new file mode 100644
index 0000000..ad29308
--- /dev/null
+++ b/tools/addon-sdk-1.5/packages/api-utils/lib/preferences-service.js
@@ -0,0 +1,103 @@
+/* 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/. */
+
+"use strict";
+
+// The minimum and maximum integers that can be set as preferences.
+// The range of valid values is narrower than the range of valid JS values
+// because the native preferences code treats integers as NSPR PRInt32s,
+// which are 32-bit signed integers on all platforms.
+const MAX_INT = 0x7FFFFFFF;
+const MIN_INT = -0x80000000;
+
+const {Cc,Ci,Cr} = require("chrome");
+
+var prefSvc = Cc["@mozilla.org/preferences-service;1"].
+              getService(Ci.nsIPrefService).getBranch(null);
+
+var get = exports.get = function get(name, defaultValue) {
+  switch (prefSvc.getPrefType(name)) {
+  case Ci.nsIPrefBranch.PREF_STRING:
+    return prefSvc.getComplexValue(name, Ci.nsISupportsString).data;
+
+  case Ci.nsIPrefBranch.PREF_INT:
+    return prefSvc.getIntPref(name);
+
+  case Ci.nsIPrefBranch.PREF_BOOL:
+    return prefSvc.getBoolPref(name);
+
+  case Ci.nsIPrefBranch.PREF_INVALID:
+    return defaultValue;
+
+  default:
+    // This should never happen.
+    throw new Error("Error getting pref " + name +
+                    "; its value's type is " +
+                    prefSvc.getPrefType(name) +
+                    ", which I don't know " +
+                    "how to handle.");
+  }
+};
+
+var set = exports.set = function set(name, value) {
+  var prefType;
+  if (typeof value != "undefined" && value != null)
+    prefType = value.constructor.name;
+
+  switch (prefType) {
+  case "String":
+    {
+      var string = Cc["@mozilla.org/supports-string;1"].
+                   createInstance(Ci.nsISupportsString);
+      string.data = value;
+      prefSvc.setComplexValue(name, Ci.nsISupportsString, string);
+    }
+    break;
+
+  case "Number":
+    // We throw if the number is outside the range or not an integer, since
+    // the result will not be what the consumer wanted to store.
+    if (value > MAX_INT || value < MIN_INT)
+      throw new Error("you cannot set the " + name +
+                      " pref to the number " + value +
+                      ", as number pref values must be in the signed " +
+                      "32-bit integer range -(2^31) to 2^31-1.  " +
+                      "To store numbers outside that range, store " +
+                      "them as strings.");
+    if (value % 1 != 0)
+      throw new Error("cannot store non-integer number: " + value);
+    prefSvc.setIntPref(name, value);
+    break;
+
+  case "Boolean":
+    prefSvc.setBoolPref(name, value);
+    break;
+
+  default:
+    throw new Error("can't set pref " + name + " to value '" + value +
+                    "'; it isn't a string, integer, or boolean");
+  }
+};
+
+var has = exports.has = function has(name) {
+  return (prefSvc.getPrefType(name) != Ci.nsIPrefBranch.PREF_INVALID);
+};
+
+var isSet = exports.isSet = function isSet(name) {
+  return (has(name) && prefSvc.prefHasUserValue(name));
+};
+
+var reset = exports.reset = function reset(name) {
+  try {
+    prefSvc.clearUserPref(name);
+  } catch (e if e.result == Cr.NS_ERROR_UNEXPECTED) {
+    // The pref service throws NS_ERROR_UNEXPECTED when the caller tries
+    // to reset a pref that doesn't exist or is already set to its default
+    // value.  This interface fails silently in those cases, so callers
+    // can unconditionally reset a pref without having to check if it needs
+    // resetting first or trap exceptions after the fact.  It passes through
+    // other exceptions, however, so callers know about them, since we don't
+    // know what other exceptions might be thrown and what they might mean.
+  }
+};