gecko-dev/dom/settings/SettingsService.js

232 lines
7.8 KiB
JavaScript

/* 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"
/* static functions */
const DEBUG = false;
function debug(s) {
dump("-*- SettingsService: " + s + "\n");
}
const Ci = Components.interfaces;
const Cu = Components.utils;
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/Services.jsm");
Cu.import('resource://gre/modules/SettingsRequestManager.jsm');
XPCOMUtils.defineLazyServiceGetter(this, "uuidgen",
"@mozilla.org/uuid-generator;1",
"nsIUUIDGenerator");
XPCOMUtils.defineLazyServiceGetter(this, "cpmm",
"@mozilla.org/childprocessmessagemanager;1",
"nsIMessageSender");
const nsIClassInfo = Ci.nsIClassInfo;
const SETTINGSSERVICELOCK_CONTRACTID = "@mozilla.org/settingsServiceLock;1";
const SETTINGSSERVICELOCK_CID = Components.ID("{d7a395a0-e292-11e1-834e-1761d57f5f99}");
const nsISettingsServiceLock = Ci.nsISettingsServiceLock;
function makeSettingsServiceRequest(aCallback, aName, aValue) {
return {
callback: aCallback,
name: aName,
value: aValue
};
};
function SettingsServiceLock(aSettingsService, aTransactionCallback) {
if (DEBUG) debug("settingsServiceLock constr!");
this._open = true;
this._settingsService = aSettingsService;
this._id = uuidgen.generateUUID().toString();
this._transactionCallback = aTransactionCallback;
this._requests = {};
let closeHelper = function() {
if (DEBUG) debug("closing lock " + this._id);
this._open = false;
this.runOrFinalizeQueries();
}.bind(this);
let msgs = ["Settings:Get:OK", "Settings:Get:KO",
"Settings:Clear:OK", "Settings:Clear:KO",
"Settings:Set:OK", "Settings:Set:KO",
"Settings:Finalize:OK", "Settings:Finalize:KO"];
for (let msg in msgs) {
cpmm.addMessageListener(msgs[msg], this);
}
cpmm.sendAsyncMessage("Settings:CreateLock", {lockID: this._id, isServiceLock: true}, undefined, Services.scriptSecurityManager.getSystemPrincipal());
Services.tm.currentThread.dispatch(closeHelper, Ci.nsIThread.DISPATCH_NORMAL);
}
SettingsServiceLock.prototype = {
get closed() {
return !this._open;
},
runOrFinalizeQueries: function() {
if (!this._requests || Object.keys(this._requests).length == 0) {
cpmm.sendAsyncMessage("Settings:Finalize", {lockID: this._id}, undefined, Services.scriptSecurityManager.getSystemPrincipal());
} else {
cpmm.sendAsyncMessage("Settings:Run", {lockID: this._id}, undefined, Services.scriptSecurityManager.getSystemPrincipal());
}
},
receiveMessage: function(aMessage) {
let msg = aMessage.data;
// SettingsRequestManager broadcasts changes to all locks in the child. If
// our lock isn't being addressed, just return.
if(msg.lockID != this._id) {
return;
}
if (DEBUG) debug("receiveMessage (" + this._id + "): " + aMessage.name);
// Finalizing a transaction does not return a request ID since we are
// supposed to fire callbacks.
if (!msg.requestID) {
switch (aMessage.name) {
case "Settings:Finalize:OK":
if (DEBUG) debug("Lock finalize ok!");
this.callTransactionHandle();
break;
case "Settings:Finalize:KO":
if (DEBUG) debug("Lock finalize failed!");
this.callAbort();
break;
default:
if (DEBUG) debug("Message type " + aMessage.name + " is missing a requestID");
}
return;
}
let req = this._requests[msg.requestID];
if (!req) {
if (DEBUG) debug("Matching request not found.");
return;
}
delete this._requests[msg.requestID];
switch (aMessage.name) {
case "Settings:Get:OK":
this._open = true;
let settings_names = Object.keys(msg.settings);
if (settings_names.length > 0) {
let name = settings_names[0];
if (DEBUG && settings_names.length > 1) {
debug("Warning: overloaded setting:" + name);
}
let result = msg.settings[name];
this.callHandle(req.callback, name, result);
} else {
this.callHandle(req.callback, req.name, null);
}
this._open = false;
break;
case "Settings:Set:OK":
this._open = true;
// We don't pass values back from sets in SettingsManager...
this.callHandle(req.callback, req.name, req.value);
this._open = false;
break;
case "Settings:Get:KO":
case "Settings:Set:KO":
if (DEBUG) debug("error:" + msg.errorMsg);
this.callError(req.callback, msg.error);
break;
default:
if (DEBUG) debug("Wrong message: " + aMessage.name);
}
this.runOrFinalizeQueries();
},
get: function get(aName, aCallback) {
if (DEBUG) debug("get (" + this._id + "): " + aName);
if (!this._open) {
dump("Settings lock not open!\n");
throw Components.results.NS_ERROR_ABORT;
}
let reqID = uuidgen.generateUUID().toString();
this._requests[reqID] = makeSettingsServiceRequest(aCallback, aName);
cpmm.sendAsyncMessage("Settings:Get", {requestID: reqID,
lockID: this._id,
name: aName},
undefined,
Services.scriptSecurityManager.getSystemPrincipal());
},
set: function set(aName, aValue, aCallback) {
if (DEBUG) debug("set: " + aName + " " + aValue);
if (!this._open) {
throw "Settings lock not open";
}
let reqID = uuidgen.generateUUID().toString();
this._requests[reqID] = makeSettingsServiceRequest(aCallback, aName, aValue);
let settings = {};
settings[aName] = aValue;
cpmm.sendAsyncMessage("Settings:Set", {requestID: reqID,
lockID: this._id,
settings: settings},
undefined,
Services.scriptSecurityManager.getSystemPrincipal());
},
callHandle: function callHandle(aCallback, aName, aValue) {
try {
aCallback ? aCallback.handle(aName, aValue) : null;
} catch (e) {
dump("settings 'handle' callback threw an exception, dropping: " + e + "\n");
}
},
callAbort: function callAbort(aCallback, aMessage) {
try {
aCallback ? aCallback.handleAbort(aMessage) : null;
} catch (e) {
dump("settings 'abort' callback threw an exception, dropping: " + e + "\n");
}
},
callError: function callError(aCallback, aMessage) {
try {
aCallback ? aCallback.handleError(aMessage) : null;
} catch (e) {
dump("settings 'error' callback threw an exception, dropping: " + e + "\n");
}
},
callTransactionHandle: function callTransactionHandle() {
try {
this._transactionCallback ? this._transactionCallback.handle() : null;
} catch (e) {
dump("settings 'Transaction handle' callback threw an exception, dropping: " + e + "\n");
}
},
classID : SETTINGSSERVICELOCK_CID,
QueryInterface : XPCOMUtils.generateQI([nsISettingsServiceLock])
};
const SETTINGSSERVICE_CID = Components.ID("{f656f0c0-f776-11e1-a21f-0800200c9a66}");
function SettingsService()
{
if (DEBUG) debug("settingsService Constructor");
}
SettingsService.prototype = {
createLock: function createLock(aCallback) {
var lock = new SettingsServiceLock(this, aCallback);
return lock;
},
classID : SETTINGSSERVICE_CID,
QueryInterface : XPCOMUtils.generateQI([Ci.nsISettingsService])
};
this.NSGetFactory = XPCOMUtils.generateNSGetFactory([SettingsService, SettingsServiceLock]);