1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/addon-sdk/source/lib/sdk/preferences/service.js Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,178 @@
1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.7 +
1.8 +"use strict";
1.9 +
1.10 +module.metadata = {
1.11 + "stability": "unstable"
1.12 +};
1.13 +
1.14 +// The minimum and maximum integers that can be set as preferences.
1.15 +// The range of valid values is narrower than the range of valid JS values
1.16 +// because the native preferences code treats integers as NSPR PRInt32s,
1.17 +// which are 32-bit signed integers on all platforms.
1.18 +const MAX_INT = 0x7FFFFFFF;
1.19 +const MIN_INT = -0x80000000;
1.20 +
1.21 +const {Cc,Ci,Cr} = require("chrome");
1.22 +
1.23 +const prefService = Cc["@mozilla.org/preferences-service;1"].
1.24 + getService(Ci.nsIPrefService);
1.25 +const prefSvc = prefService.getBranch(null);
1.26 +const defaultBranch = prefService.getDefaultBranch(null);
1.27 +
1.28 +function Branch(branchName) {
1.29 + function getPrefKeys() {
1.30 + return keys(branchName).map(function(key) {
1.31 + return key.replace(branchName, "");
1.32 + });
1.33 + }
1.34 +
1.35 + return Proxy.create({
1.36 + get: function(receiver, pref) {
1.37 + return get(branchName + pref);
1.38 + },
1.39 + set: function(receiver, pref, val) {
1.40 + set(branchName + pref, val);
1.41 + },
1.42 + delete: function(pref) {
1.43 + reset(branchName + pref);
1.44 + return true;
1.45 + },
1.46 + has: function hasPrefKey(pref) {
1.47 + return has(branchName + pref)
1.48 + },
1.49 + getPropertyDescriptor: function(name) {
1.50 + return {
1.51 + value: get(branchName + name)
1.52 + };
1.53 + },
1.54 + enumerate: getPrefKeys,
1.55 + keys: getPrefKeys
1.56 + }, Branch.prototype);
1.57 +}
1.58 +
1.59 +function get(name, defaultValue) {
1.60 + switch (prefSvc.getPrefType(name)) {
1.61 + case Ci.nsIPrefBranch.PREF_STRING:
1.62 + return prefSvc.getComplexValue(name, Ci.nsISupportsString).data;
1.63 +
1.64 + case Ci.nsIPrefBranch.PREF_INT:
1.65 + return prefSvc.getIntPref(name);
1.66 +
1.67 + case Ci.nsIPrefBranch.PREF_BOOL:
1.68 + return prefSvc.getBoolPref(name);
1.69 +
1.70 + case Ci.nsIPrefBranch.PREF_INVALID:
1.71 + return defaultValue;
1.72 +
1.73 + default:
1.74 + // This should never happen.
1.75 + throw new Error("Error getting pref " + name +
1.76 + "; its value's type is " +
1.77 + prefSvc.getPrefType(name) +
1.78 + ", which I don't know " +
1.79 + "how to handle.");
1.80 + }
1.81 +}
1.82 +exports.get = get;
1.83 +
1.84 +function set(name, value) {
1.85 + var prefType;
1.86 + if (typeof value != "undefined" && value != null)
1.87 + prefType = value.constructor.name;
1.88 +
1.89 + switch (prefType) {
1.90 + case "String":
1.91 + {
1.92 + var string = Cc["@mozilla.org/supports-string;1"].
1.93 + createInstance(Ci.nsISupportsString);
1.94 + string.data = value;
1.95 + prefSvc.setComplexValue(name, Ci.nsISupportsString, string);
1.96 + }
1.97 + break;
1.98 +
1.99 + case "Number":
1.100 + // We throw if the number is outside the range or not an integer, since
1.101 + // the result will not be what the consumer wanted to store.
1.102 + if (value > MAX_INT || value < MIN_INT)
1.103 + throw new Error("you cannot set the " + name +
1.104 + " pref to the number " + value +
1.105 + ", as number pref values must be in the signed " +
1.106 + "32-bit integer range -(2^31) to 2^31-1. " +
1.107 + "To store numbers outside that range, store " +
1.108 + "them as strings.");
1.109 + if (value % 1 != 0)
1.110 + throw new Error("cannot store non-integer number: " + value);
1.111 + prefSvc.setIntPref(name, value);
1.112 + break;
1.113 +
1.114 + case "Boolean":
1.115 + prefSvc.setBoolPref(name, value);
1.116 + break;
1.117 +
1.118 + default:
1.119 + throw new Error("can't set pref " + name + " to value '" + value +
1.120 + "'; it isn't a string, integer, or boolean");
1.121 + }
1.122 +}
1.123 +exports.set = set;
1.124 +
1.125 +function has(name) {
1.126 + return (prefSvc.getPrefType(name) != Ci.nsIPrefBranch.PREF_INVALID);
1.127 +}
1.128 +exports.has = has;
1.129 +
1.130 +function keys(root) {
1.131 + return prefSvc.getChildList(root);
1.132 +}
1.133 +exports.keys = keys;
1.134 +
1.135 +function isSet(name) {
1.136 + return (has(name) && prefSvc.prefHasUserValue(name));
1.137 +}
1.138 +exports.isSet = isSet;
1.139 +
1.140 +function reset(name) {
1.141 + try {
1.142 + prefSvc.clearUserPref(name);
1.143 + }
1.144 + catch (e) {
1.145 + // The pref service throws NS_ERROR_UNEXPECTED when the caller tries
1.146 + // to reset a pref that doesn't exist or is already set to its default
1.147 + // value. This interface fails silently in those cases, so callers
1.148 + // can unconditionally reset a pref without having to check if it needs
1.149 + // resetting first or trap exceptions after the fact. It passes through
1.150 + // other exceptions, however, so callers know about them, since we don't
1.151 + // know what other exceptions might be thrown and what they might mean.
1.152 + if (e.result != Cr.NS_ERROR_UNEXPECTED) {
1.153 + throw e;
1.154 + }
1.155 + }
1.156 +}
1.157 +exports.reset = reset;
1.158 +
1.159 +function getLocalized(name, defaultValue) {
1.160 + let value = null;
1.161 + try {
1.162 + value = prefSvc.getComplexValue(name, Ci.nsIPrefLocalizedString).data;
1.163 + }
1.164 + finally {
1.165 + return value || defaultValue;
1.166 + }
1.167 +}
1.168 +exports.getLocalized = getLocalized;
1.169 +
1.170 +function setLocalized(name, value) {
1.171 + // We can't use `prefs.set` here as we have to use `getDefaultBranch`
1.172 + // (instead of `getBranch`) in order to have `mIsDefault` set to true, here:
1.173 + // http://mxr.mozilla.org/mozilla-central/source/modules/libpref/src/nsPrefBranch.cpp#233
1.174 + // Otherwise, we do not enter into this expected condition:
1.175 + // http://mxr.mozilla.org/mozilla-central/source/modules/libpref/src/nsPrefBranch.cpp#244
1.176 + defaultBranch.setCharPref(name, value);
1.177 +}
1.178 +exports.setLocalized = setLocalized;
1.179 +
1.180 +exports.Branch = Branch;
1.181 +
