gecko-dev/dom/settings/SettingsRequestManager.jsm

925 lines
34 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";
const DEBUG = false;
function debug(s) { dump("-*- SettingsRequestManager: " + s + "\n"); }
const Cc = Components.classes;
const Ci = Components.interfaces;
const Cu = Components.utils;
this.EXPORTED_SYMBOLS = ["SettingsRequestManager"];
Cu.import("resource://gre/modules/SettingsDB.jsm");
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/PermissionsTable.jsm");
const kXpcomShutdownObserverTopic = "xpcom-shutdown";
const kMozSettingsChangedObserverTopic = "mozsettings-changed";
const kSettingsReadSuffix = "-read";
const kSettingsWriteSuffix = "-write";
const kSettingsClearPermission = "settings-clear";
const kAllSettingsReadPermission = "settings" + kSettingsReadSuffix;
const kAllSettingsWritePermission = "settings" + kSettingsWriteSuffix;
// Any application with settings permissions, be it for all settings
// or a single one, will need to be able to access the settings API.
// The settings-api permission allows an app to see the mozSettings
// API in order to create locks and queue tasks. Whether these tasks
// will be allowed depends on the exact permissions the app has.
const kSomeSettingsReadPermission = "settings-api" + kSettingsReadSuffix;
const kSomeSettingsWritePermission = "settings-api" + kSettingsWriteSuffix;
XPCOMUtils.defineLazyServiceGetter(this, "ppmm",
"@mozilla.org/parentprocessmessagemanager;1",
"nsIMessageBroadcaster");
XPCOMUtils.defineLazyServiceGetter(this, "uuidgen",
"@mozilla.org/uuid-generator;1",
"nsIUUIDGenerator");
let SettingsPermissions = {
checkPermission: function(aPrincipal, aPerm) {
if (aPrincipal.origin == "[System Principal]" ||
Services.perms.testExactPermissionFromPrincipal(aPrincipal, aPerm) == Ci.nsIPermissionManager.ALLOW_ACTION) {
return true;
}
return false;
},
hasAllReadPermission: function(aPrincipal) {
return this.checkPermission(aPrincipal, kAllSettingsReadPermission);
},
hasAllWritePermission: function(aPrincipal) {
return this.checkPermission(aPrincipal, kAllSettingsWritePermission);
},
hasSomeReadPermission: function(aPrincipal) {
return this.checkPermission(aPrincipal, kSomeSettingsReadPermission);
},
hasSomeWritePermission: function(aPrincipal) {
return this.checkPermission(aPrincipal, kSomeSettingsWritePermission);
},
hasClearPermission: function(aPrincipal) {
return this.checkPermission(aPrincipal, kSettingsClearPermission);
},
hasReadPermission: function(aPrincipal, aSettingsName) {
return this.hasAllReadPermission(aPrincipal) || this.checkPermission(aPrincipal, "settings:" + aSettingsName + kSettingsReadSuffix);
},
hasWritePermission: function(aPrincipal, aSettingsName) {
return this.hasAllWritePermission(aPrincipal) || this.checkPermission(aPrincipal, "settings:" + aSettingsName + kSettingsWriteSuffix);
}
};
function SettingsLockInfo(aDB, aMsgMgr, aLockID, aIsServiceLock) {
return {
// ID Shared with the object on the child side
lockID: aLockID,
// Is this a content lock or a settings service lock?
isServiceLock: aIsServiceLock,
// Tasks to be run once the lock is at the head of the queue
tasks: [],
// This is set to true once a transaction is ready to run, but is not at the
// head of the lock queue.
consumable: false,
// Holds values that are requested to be set until the lock lifetime ends,
// then commits them to the DB.
queuedSets: {},
// Internal transaction object
_transaction: undefined,
// Message manager that controls the lock
_mm: aMsgMgr,
// If true, it means a permissions check failed, so just fail everything now
_failed: false,
// If we're slated to run finalize, set this to make sure we don't
// somehow run other events afterward.
finalizing: false,
// Lets us know if we can use this lock for a clear command
canClear: true,
// Lets us know if this lock has been used to clear at any point.
hasCleared: false,
getObjectStore: function(aPrincipal) {
if (DEBUG) debug("Getting transaction for " + this.lockID);
let store;
// Test for transaction validity via trying to get the
// datastore. If it doesn't work, assume the transaction is
// closed, create a new transaction and try again.
if (this._transaction) {
try {
store = this._transaction.objectStore(SETTINGSSTORE_NAME);
} catch (e) {
if (e.name == "InvalidStateError") {
if (DEBUG) debug("Current transaction for " + this.lockID + " closed, trying to create new one.");
} else {
throw e;
}
}
}
// Create one transaction with a global permission. This may be
// slightly slower on apps with full settings permissions, but
// it means we don't have to do our own transaction order
// bookkeeping.
if (!SettingsPermissions.hasSomeWritePermission(aPrincipal)) {
if (DEBUG) debug("Making READONLY transaction for " + this.lockID);
this._transaction = aDB._db.transaction(SETTINGSSTORE_NAME, "readonly");
} else {
if (DEBUG) debug("Making READWRITE transaction for " + this.lockID);
this._transaction = aDB._db.transaction(SETTINGSSTORE_NAME, "readwrite");
}
this._transaction.oncomplete = function() {
if (DEBUG) debug("Transaction for lock " + this.lockID + " closed");
}.bind(this);
this._transaction.onabort = function () {
if (DEBUG) debug("Transaction for lock " + this.lockID + " aborted");
this._failed = true;
}.bind(this);
try {
store = this._transaction.objectStore(SETTINGSSTORE_NAME);
} catch (e) {
if (e.name == "InvalidStateError") {
if (DEBUG) debug("Cannot create objectstore on transaction for " + this.lockID);
return null;
} else {
throw e;
}
}
return store;
}
};
}
let SettingsRequestManager = {
// Access to the settings DB
settingsDB: new SettingsDB(),
// Remote messages to listen for from child
messages: ["child-process-shutdown", "Settings:Get", "Settings:Set",
"Settings:Clear", "Settings:Run", "Settings:Finalize",
"Settings:CreateLock", "Settings:RegisterForMessages"],
// Map of LockID to SettingsLockInfo objects
lockInfo: {},
// Queue of LockIDs. The LockID on the front of the queue is the only lock
// that will have requests processed, all other locks will queue requests
// until they hit the front of the queue.
settingsLockQueue: [],
children: [],
mmPrincipals: new Map(),
init: function() {
if (DEBUG) debug("init");
this.settingsDB.init();
this.messages.forEach((function(msgName) {
ppmm.addMessageListener(msgName, this);
}).bind(this));
Services.obs.addObserver(this, kXpcomShutdownObserverTopic, false);
},
_serializePreservingBinaries: function _serializePreservingBinaries(aObject) {
function needsUUID(aValue) {
if (!aValue || !aValue.constructor) {
return false;
}
return (aValue.constructor.name == "Date") || (aValue instanceof Ci.nsIDOMFile) ||
(aValue instanceof Ci.nsIDOMBlob);
}
// We need to serialize settings objects, otherwise they can change between
// the set() call and the enqueued request being processed. We can't simply
// parse(stringify(obj)) because that breaks things like Blobs, Files and
// Dates, so we use stringify's replacer and parse's reviver parameters to
// preserve binaries.
let binaries = Object.create(null);
let stringified = JSON.stringify(aObject, function(key, value) {
value = this.settingsDB.prepareValue(value);
if (needsUUID(value)) {
let uuid = uuidgen.generateUUID().toString();
binaries[uuid] = value;
return uuid;
}
return value;
}.bind(this));
return JSON.parse(stringified, function(key, value) {
if (value in binaries) {
return binaries[value];
}
return value;
});
},
queueTask: function(aOperation, aData, aPrincipal) {
if (DEBUG) debug("Queueing task: " + aOperation);
let defer = {};
let lock = this.lockInfo[aData.lockID];
if (!lock) {
return Promise.reject({error: "Lock already dead, cannot queue task"});
}
if (aOperation == "set") {
aData.settings = this._serializePreservingBinaries(aData.settings);
}
this.lockInfo[aData.lockID].tasks.push({
operation: aOperation,
data: aData,
principal: aPrincipal,
defer: defer
});
let promise = new Promise(function(resolve, reject) {
defer.resolve = resolve;
defer.reject = reject;
});
return promise;
},
// Due to the fact that we're skipping the database in some places
// by keeping a local "set" value cache, resolving some calls
// without a call to the database would mean we could potentially
// receive promise responses out of expected order if a get is
// called before a set. Therefore, we wrap our resolve in a null
// get, which means it will resolves afer the rest of the calls
// queued to the DB.
queueTaskReturn: function(aTask, aReturnValue) {
if (DEBUG) debug("Making task queuing transaction request.");
let data = aTask.data;
let lock = this.lockInfo[data.lockID];
let store = lock.getObjectStore(aTask.principal);
if (!store) {
if (DEBUG) debug("Rejecting task queue on lock " + aTask.data.lockID);
return Promise.reject({task: aTask, error: "Cannot get object store"});
}
// Due to the fact that we're skipping the database, resolving
// this without a call to the database would mean we could
// potentially receive promise responses out of expected order if
// a get is called before a set. Therefore, we wrap our resolve in
// a null get, which means it will resolves afer the rest of the
// calls queued to the DB.
let getReq = store.get(0);
let defer = {};
let promiseWrapper = new Promise(function(resolve, reject) {
defer.resolve = resolve;
defer.reject = reject;
});
getReq.onsuccess = function(event) {
return defer.resolve(aReturnValue);
};
getReq.onerror = function() {
return defer.reject({task: aTask, error: getReq.error.name});
};
return promiseWrapper;
},
taskGet: function(aTask) {
if (DEBUG) debug("Running Get task on lock " + aTask.data.lockID);
// Check that we have permissions for getting the value
let data = aTask.data;
let lock = this.lockInfo[data.lockID];
if (!lock) {
return Promise.reject({task: aTask, error: "Lock died, can't finalize"});
}
if (lock._failed) {
if (DEBUG) debug("Lock failed. All subsequent requests will fail.");
return Promise.reject({task: aTask, error: "Lock failed, all requests now failing."});
}
if (lock.hasCleared) {
if (DEBUG) debug("Lock was used for a clear command. All subsequent requests will fail.");
return Promise.reject({task: aTask, error: "Lock was used for a clear command. All subsequent requests will fail."});
}
lock.canClear = false;
if (!SettingsPermissions.hasReadPermission(aTask.principal, data.name)) {
if (DEBUG) debug("get not allowed for " + data.name);
lock._failed = true;
return Promise.reject({task: aTask, error: "No permission to get " + data.name});
}
// If the value was set during this transaction, use the cached value
if (data.name in lock.queuedSets) {
if (DEBUG) debug("Returning cached set value " + lock.queuedSets[data.name] + " for " + data.name);
let local_results = {};
local_results[data.name] = lock.queuedSets[data.name];
return this.queueTaskReturn(aTask, {task: aTask, results: local_results});
}
// Create/Get transaction and make request
if (DEBUG) debug("Making get transaction request for " + data.name);
let store = lock.getObjectStore(aTask.principal);
if (!store) {
if (DEBUG) debug("Rejecting Get task on lock " + aTask.data.lockID);
return Promise.reject({task: aTask, error: "Cannot get object store"});
}
if (DEBUG) debug("Making get request for " + data.name);
let getReq = (data.name === "*") ? store.mozGetAll() : store.mozGetAll(data.name);
let defer = {};
let promiseWrapper = new Promise(function(resolve, reject) {
defer.resolve = resolve;
defer.reject = reject;
});
getReq.onsuccess = function(event) {
if (DEBUG) debug("Request for '" + data.name + "' successful. " +
"Record count: " + event.target.result.length);
if (event.target.result.length == 0) {
if (DEBUG) debug("MOZSETTINGS-GET-WARNING: " + data.name + " is not in the database.\n");
}
let results = {};
for (let i in event.target.result) {
let result = event.target.result[i];
let name = result.settingName;
if (DEBUG) debug(name + ": " + result.userValue +", " + result.defaultValue);
let value = result.userValue !== undefined ? result.userValue : result.defaultValue;
results[name] = value;
}
return defer.resolve({task: aTask, results: results});
};
getReq.onerror = function() {
return defer.reject({task: aTask, error: getReq.error.name});
};
return promiseWrapper;
},
taskSet: function(aTask) {
let data = aTask.data;
let lock = this.lockInfo[data.lockID];
let keys = Object.getOwnPropertyNames(data.settings);
if (!lock) {
return Promise.reject({task: aTask, error: "Lock died, can't finalize"});
}
if (lock._failed) {
if (DEBUG) debug("Lock failed. All subsequent requests will fail.");
return Promise.reject({task: aTask, error: "Lock failed a permissions check, all requests now failing."});
}
if (lock.hasCleared) {
if (DEBUG) debug("Lock was used for a clear command. All subsequent requests will fail.");
return Promise.reject({task: aTask, error: "Lock was used for a clear command. All other requests will fail."});
}
lock.canClear = false;
// If we have no keys, resolve
if (keys.length === 0) {
if (DEBUG) debug("No keys to change entered!");
return Promise.resolve({task: aTask});
}
for (let i = 0; i < keys.length; i++) {
if (!SettingsPermissions.hasWritePermission(aTask.principal, keys[i])) {
if (DEBUG) debug("set not allowed on " + keys[i]);
lock._failed = true;
return Promise.reject({task: aTask, error: "No permission to set " + keys[i]});
}
}
for (let i = 0; i < keys.length; i++) {
let key = keys[i];
if (DEBUG) debug("key: " + key + ", val: " + JSON.stringify(data.settings[key]) + ", type: " + typeof(data.settings[key]));
lock.queuedSets[key] = data.settings[key];
}
return this.queueTaskReturn(aTask, {task: aTask});
},
queueConsume: function() {
if (this.settingsLockQueue.length > 0 && this.lockInfo[this.settingsLockQueue[0]].consumable) {
Services.tm.currentThread.dispatch(SettingsRequestManager.consumeTasks.bind(this), Ci.nsIThread.DISPATCH_NORMAL);
}
},
finalizeSets: function(aTask) {
let data = aTask.data;
if (DEBUG) debug("Finalizing tasks for lock " + data.lockID);
let lock = this.lockInfo[data.lockID];
if (!lock) {
return Promise.reject({task: aTask, error: "Lock died, can't finalize"});
}
lock.finalizing = true;
if (lock._failed) {
this.removeLock(data.lockID);
return Promise.reject({task: aTask, error: "Lock failed a permissions check, all requests now failing."});
}
// If we have cleared, there is no reason to continue finalizing
// this lock. Just resolve promise with task and move on.
if (lock.hasCleared) {
if (DEBUG) debug("Clear was called on lock, skipping finalize");
this.removeLock(data.lockID);
return Promise.resolve({task: aTask});
}
let keys = Object.getOwnPropertyNames(lock.queuedSets);
if (keys.length === 0) {
if (DEBUG) debug("Nothing to finalize. Exiting.");
this.removeLock(data.lockID);
return Promise.resolve({task: aTask});
}
let store = lock.getObjectStore(aTask.principal);
if (!store) {
if (DEBUG) debug("Rejecting Set task on lock " + aTask.data.lockID);
return Promise.reject({task: aTask, error: "Cannot get object store"});
}
// Due to the fact there may have multiple set operations to clear, and
// they're all async, callbacks are gathered into promises, and the promises
// are processed with Promises.all().
let checkPromises = [];
let finalValues = {};
for (let i = 0; i < keys.length; i++) {
let key = keys[i];
if (DEBUG) debug("key: " + key + ", val: " + lock.queuedSets[key] + ", type: " + typeof(lock.queuedSets[key]));
let checkDefer = {};
let checkPromise = new Promise(function(resolve, reject) {
checkDefer.resolve = resolve;
checkDefer.reject = reject;
});
// Get operation is used to fill in the default value, assuming there is
// one. For the moment, if a value doesn't exist in the settings DB, we
// allow the user to add it, and just pass back a null default value.
let checkKeyRequest = store.get(key);
checkKeyRequest.onsuccess = function (event) {
let userValue = lock.queuedSets[key];
let defaultValue;
if (!event.target.result) {
defaultValue = null;
if (DEBUG) debug("MOZSETTINGS-GET-WARNING: " + key + " is not in the database.\n");
} else {
defaultValue = event.target.result.defaultValue;
}
let obj = {settingName: key, defaultValue: defaultValue, userValue: userValue};
finalValues[key] = {defaultValue: defaultValue, userValue: userValue};
let setReq = store.put(obj);
setReq.onsuccess = function() {
if (DEBUG) debug("Set successful!");
if (DEBUG) debug("key: " + key + ", val: " + finalValues[key] + ", type: " + typeof(finalValues[key]));
return checkDefer.resolve({task: aTask});
};
setReq.onerror = function() {
return checkDefer.reject({task: aTask, error: setReq.error.name});
};
}.bind(this);
checkKeyRequest.onerror = function(event) {
return checkDefer.reject({task: aTask, error: checkKeyRequest.error.name});
};
checkPromises.push(checkPromise);
}
let defer = {};
let promiseWrapper = new Promise(function(resolve, reject) {
defer.resolve = resolve;
defer.reject = reject;
});
// Once all transactions are done, or any have failed, remove the lock and
// start processing the tasks from the next lock in the queue.
Promise.all(checkPromises).then(function() {
// If all commits were successful, notify observers
for (let i = 0; i < keys.length; i++) {
this.sendSettingsChange(keys[i], finalValues[keys[i]].userValue, lock.isServiceLock);
}
this.removeLock(data.lockID);
defer.resolve({task: aTask});
}.bind(this), function(ret) {
this.removeLock(data.lockID);
defer.reject({task: aTask, error: "Set transaction failure"});
}.bind(this));
return promiseWrapper;
},
// Clear is only expected to be called via tests, and if a lock
// calls clear, it should be the only thing the lock does. This
// allows us to not have to deal with the possibility of query
// integrity checking. Clear should never be called in the wild,
// even by certified apps, which is why it has its own permission
// (settings-clear).
taskClear: function(aTask) {
if (DEBUG) debug("Clearing");
let data = aTask.data;
let lock = this.lockInfo[data.lockID];
if (lock._failed) {
if (DEBUG) debug("Lock failed, all requests now failing.");
return Promise.reject({task: aTask, error: "Lock failed, all requests now failing."});
}
if (!lock.canClear) {
if (DEBUG) debug("Lock tried to clear after queuing other tasks. Failing.");
lock._failed = true;
return Promise.reject({task: aTask, error: "Cannot call clear after queuing other tasks, all requests now failing."});
}
if (!SettingsPermissions.hasClearPermission(aTask.principal)) {
if (DEBUG) debug("clear not allowed");
lock._failed = true;
return Promise.reject({task: aTask, error: "No permission to clear DB"});
}
lock.hasCleared = true;
let store = lock.getObjectStore(aTask.principal);
if (!store) {
if (DEBUG) debug("Rejecting Clear task on lock " + aTask.data.lockID);
return Promise.reject({task: aTask, error: "Cannot get object store"});
}
let defer = {};
let promiseWrapper = new Promise(function(resolve, reject) {
defer.resolve = resolve;
defer.reject = reject;
});
let clearReq = store.clear();
clearReq.onsuccess = function() {
return defer.resolve({task: aTask});
};
clearReq.onerror = function() {
return defer.reject({task: aTask});
};
return promiseWrapper;
},
ensureConnection : function() {
if (DEBUG) debug("Ensuring Connection");
let defer = {};
let promiseWrapper = new Promise(function(resolve, reject) {
defer.resolve = resolve;
defer.reject = reject;
});
this.settingsDB.ensureDB(
function() { defer.resolve(); },
function(error) {
if (DEBUG) debug("Cannot open Settings DB. Trying to open an old version?\n");
defer.reject(error);
}
);
return promiseWrapper;
},
runTasks: function(aLockID) {
if (DEBUG) debug("Running tasks for " + aLockID);
let lock = this.lockInfo[aLockID];
if (!lock) {
if (DEBUG) debug("Lock no longer alive, cannot run tasks");
return;
}
let currentTask = lock.tasks.shift();
let promises = [];
while (currentTask) {
if (DEBUG) debug("Running Operation " + currentTask.operation);
if (lock.finalizing) {
// We should really never get to this point, but if we do,
// fail every task that happens.
Cu.reportError("Settings lock trying to run more tasks after finalizing. Ignoring tasks, but this is bad. Lock: " + aLockID);
currentTask.defer.reject("Cannot call new task after finalizing");
} else {
let p;
switch (currentTask.operation) {
case "get":
p = this.taskGet(currentTask);
break;
case "set":
p = this.taskSet(currentTask);
break;
case "clear":
p = this.taskClear(currentTask);
break;
case "finalize":
p = this.finalizeSets(currentTask);
break;
default:
if (DEBUG) debug("Invalid operation: " + currentTask.operation);
p.reject("Invalid operation: " + currentTask.operation);
}
p.then(function(ret) {
ret.task.defer.resolve("results" in ret ? ret.results : null);
}.bind(currentTask), function(ret) {
ret.task.defer.reject(ret.error);
});
promises.push(p);
}
currentTask = lock.tasks.shift();
}
},
consumeTasks: function() {
if (this.settingsLockQueue.length == 0) {
if (DEBUG) debug("Nothing to run!");
return;
}
let lockID = this.settingsLockQueue[0];
if (DEBUG) debug("Consuming tasks for " + lockID);
let lock = this.lockInfo[lockID];
// If a process dies, we should clean up after it via the
// child-process-shutdown event. But just in case we don't, we want to make
// sure we never block on consuming.
if (!lock) {
if (DEBUG) debug("Lock no longer alive, cannot consume tasks");
this.queueConsume();
return;
}
if (!lock.consumable || lock.tasks.length === 0) {
if (DEBUG) debug("No more tasks to run or not yet consuamble.");
return;
}
lock.consumable = false;
this.ensureConnection().then(
function(task) {
this.runTasks(lockID);
}.bind(this), function(ret) {
dump("-*- SettingsRequestManager: SETTINGS DATABASE ERROR: Cannot make DB connection!\n");
});
},
observe: function(aSubject, aTopic, aData) {
if (DEBUG) debug("observe");
switch (aTopic) {
case kXpcomShutdownObserverTopic:
this.messages.forEach((function(msgName) {
ppmm.removeMessageListener(msgName, this);
}).bind(this));
Services.obs.removeObserver(this, kXpcomShutdownObserverTopic);
ppmm = null;
break;
default:
if (DEBUG) debug("Wrong observer topic: " + aTopic);
break;
}
},
sendSettingsChange: function(aKey, aValue, aIsServiceLock) {
this.broadcastMessage("Settings:Change:Return:OK",
{ key: aKey, value: aValue });
var setting = {
key: aKey,
value: aValue,
isInternalChange: aIsServiceLock
};
setting.wrappedJSObject = setting;
Services.obs.notifyObservers(setting, kMozSettingsChangedObserverTopic, "");
},
broadcastMessage: function broadcastMessage(aMsgName, aContent) {
if (DEBUG) debug("Broadcast");
this.children.forEach(function(msgMgr) {
let principal = this.mmPrincipals.get(msgMgr);
if (!principal) {
if (DEBUG) debug("Cannot find principal for message manager to check permissions");
}
else if (SettingsPermissions.hasReadPermission(principal, aContent.key)) {
try {
msgMgr.sendAsyncMessage(aMsgName, aContent);
} catch (e) {
if (DEBUG) debug("Failed sending message: " + aMsgName);
}
}
}.bind(this));
if (DEBUG) debug("Finished Broadcasting");
},
addObserver: function(aMsgMgr, aPrincipal) {
if (DEBUG) debug("Add observer for " + aPrincipal.origin);
if (this.children.indexOf(aMsgMgr) == -1) {
this.children.push(aMsgMgr);
this.mmPrincipals.set(aMsgMgr, aPrincipal);
}
},
removeObserver: function(aMsgMgr) {
if (DEBUG) {
let principal = this.mmPrincipals.get(aMsgMgr);
debug("Remove observer for " + principal.origin);
}
let index = this.children.indexOf(aMsgMgr);
if (index != -1) {
this.children.splice(index, 1);
this.mmPrincipals.delete(aMsgMgr);
}
if (DEBUG) debug("Principal/MessageManager pairs left: " + this.mmPrincipals.size);
},
removeLock: function(aLockID) {
if (DEBUG) debug("Removing lock " + aLockID);
if (this.lockInfo[aLockID]) {
let transaction = this.lockInfo[aLockID]._transaction;
if (transaction) {
try {
transaction.abort();
} catch (e) {
if (e.name == "InvalidStateError") {
if (DEBUG) debug("Transaction for " + aLockID + " closed already");
} else {
throw e;
}
}
}
delete this.lockInfo[aLockID];
}
let index = this.settingsLockQueue.indexOf(aLockID);
if (index > -1) {
this.settingsLockQueue.splice(index, 1);
}
// If index is 0, the lock we just removed was at the head of
// the queue, so possibly queue the next lock if it's
// consumable.
if (index == 0) {
this.queueConsume();
}
},
removeMessageManager: function(aMsgMgr){
if (DEBUG) debug("Removing message manager");
this.removeObserver(aMsgMgr);
let closedLockIDs = [];
let lockIDs = Object.keys(this.lockInfo);
for (let i in lockIDs) {
if (this.lockInfo[lockIDs[i]]._mm == aMsgMgr) {
if (DEBUG) debug("Removing lock " + lockIDs[i] + " due to process close/crash");
closedLockIDs.push(lockIDs[i]);
}
}
for (let i in closedLockIDs) {
this.removeLock(closedLockIDs[i]);
}
},
receiveMessage: function(aMessage) {
if (DEBUG) debug("receiveMessage " + aMessage.name);
let msg = aMessage.data;
let mm = aMessage.target;
function returnMessage(name, data) {
try {
mm.sendAsyncMessage(name, data);
} catch (e) {
if (DEBUG) debug("Return message failed, " + name);
}
}
// For all message types that expect a lockID, we check to make
// sure that we're accessing a lock that's part of our process. If
// not, consider it a security violation and kill the app. Killing
// based on creating a colliding lock ID happens as part of
// CreateLock check below.
switch (aMessage.name) {
case "Settings:Get":
case "Settings:Set":
case "Settings:Clear":
case "Settings:Run":
case "Settings:Finalize":
let kill_process = false;
if (!msg.lockID) {
Cu.reportError("Process sending request for lock that does not exist. Killing.");
kill_process = true;
}
else if (!this.lockInfo[msg.lockID]) {
if (DEBUG) debug("Cannot find lock ID " + msg.lockID);
// This doesn't kill, because we can have things that file
// finalize, then die, and we may get the observer
// notification before we get the IPC messages.
return;
}
else if (mm != this.lockInfo[msg.lockID]._mm) {
Cu.reportError("Process trying to access settings lock from another process. Killing.");
kill_process = true;
}
if (kill_process) {
// Kill the app by checking for a non-existent permission
aMessage.target.assertPermission("message-manager-mismatch-kill");
return;
}
default:
break;
}
switch (aMessage.name) {
case "child-process-shutdown":
if (DEBUG) debug("Child process shutdown received.");
this.removeMessageManager(mm);
break;
case "Settings:RegisterForMessages":
if (!SettingsPermissions.hasSomeReadPermission(aMessage.principal)) {
Cu.reportError("Settings message " + aMessage.name +
" from a content process with no 'settings-api-read' privileges.");
aMessage.target.assertPermission("message-manager-no-read-kill");
return;
}
this.addObserver(mm, aMessage.principal);
break;
case "Settings:UnregisterForMessages":
this.removeObserver(mm);
break;
case "Settings:CreateLock":
if (DEBUG) debug("Received CreateLock for " + msg.lockID + " from " + aMessage.principal.origin);
// If we try to create a lock ID that collides with one
// already in the system, consider it a security violation and
// kill.
if (msg.lockID in this.settingsLockQueue) {
Cu.reportError("Trying to queue a lock with the same ID as an already queued lock. Killing app.");
aMessage.target.assertPermission("lock-id-duplicate-kill");
return;
}
this.settingsLockQueue.push(msg.lockID);
this.lockInfo[msg.lockID] = SettingsLockInfo(this.settingsDB, mm, msg.lockID, msg.isServiceLock);
break;
case "Settings:Get":
if (DEBUG) debug("Received getRequest from " + msg.lockID);
this.queueTask("get", msg, aMessage.principal).then(function(settings) {
returnMessage("Settings:Get:OK", {
lockID: msg.lockID,
requestID: msg.requestID,
settings: settings
});
}, function(error) {
if (DEBUG) debug("getRequest FAILED " + msg.name);
returnMessage("Settings:Get:KO", {
lockID: msg.lockID,
requestID: msg.requestID,
errorMsg: error
});
});
break;
case "Settings:Set":
if (DEBUG) debug("Received Set Request from " + msg.lockID);
this.queueTask("set", msg, aMessage.principal).then(function(settings) {
returnMessage("Settings:Set:OK", {
lockID: msg.lockID,
requestID: msg.requestID
});
}, function(error) {
returnMessage("Settings:Set:KO", {
lockID: msg.lockID,
requestID: msg.requestID,
errorMsg: error
});
});
break;
case "Settings:Clear":
if (DEBUG) debug("Received Clear Request from " + msg.lockID);
this.queueTask("clear", msg, aMessage.principal).then(function() {
returnMessage("Settings:Clear:OK", {
lockID: msg.lockID,
requestID: msg.requestID
});
}, function(error) {
returnMessage("Settings:Clear:KO", {
lockID: msg.lockID,
requestID: msg.requestID,
errorMsg: error
});
});
break;
case "Settings:Finalize":
if (DEBUG) debug("Received Finalize");
this.queueTask("finalize", msg, aMessage.principal).then(function() {
returnMessage("Settings:Finalize:OK", {
lockID: msg.lockID
});
}, function(error) {
returnMessage("Settings:Finalize:KO", {
lockID: msg.lockID,
errorMsg: error
});
});
// YES THIS IS SUPPOSED TO FALL THROUGH. Finalize is considered a task
// running situation, but it also needs to queue a task.
case "Settings:Run":
if (DEBUG) debug("Received Run");
this.lockInfo[msg.lockID].consumable = true;
if (msg.lockID == this.settingsLockQueue[0] || this.settingsLockQueue.length == 0) {
// If a lock is currently at the head of the queue, run all tasks for
// it.
if (DEBUG) debug("Running tasks for " + msg.lockID);
this.queueConsume();
} else {
// If a lock isn't at the head of the queue, but requests to be run,
// simply mark it as consumable, which means it will automatically run
// once it comes to the head of the queue.
if (DEBUG) debug("Queuing tasks for " + msg.lockID + " while waiting for " + this.settingsLockQueue[0]);
}
break;
default:
if (DEBUG) debug("Wrong message: " + aMessage.name);
}
}
};
SettingsRequestManager.init();