gecko-dev/toolkit/modules/AsyncPrefs.jsm

184 строки
5.1 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";
this.EXPORTED_SYMBOLS = ["AsyncPrefs"];
const {interfaces: Ci, utils: Cu, classes: Cc} = Components;
Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/Task.jsm");
const kInChildProcess = Services.appinfo.processType == Services.appinfo.PROCESS_TYPE_CONTENT;
const kAllowedPrefs = new Set([
// NB: please leave the testing prefs at the top, and sort the rest alphabetically if you add
// anything.
"testing.allowed-prefs.some-bool-pref",
"testing.allowed-prefs.some-char-pref",
"testing.allowed-prefs.some-int-pref",
"narrate.rate",
"narrate.voice",
"reader.font_size",
"reader.font_type",
"reader.color_scheme",
"reader.content_width",
"reader.line_height",
]);
const kPrefTypeMap = new Map([
["boolean", Services.prefs.PREF_BOOL],
["number", Services.prefs.PREF_INT],
["string", Services.prefs.PREF_STRING],
]);
function maybeReturnErrorForReset(pref) {
if (!kAllowedPrefs.has(pref)) {
return `Resetting pref ${pref} from content is not allowed.`;
}
return false;
}
function maybeReturnErrorForSet(pref, value) {
if (!kAllowedPrefs.has(pref)) {
return `Setting pref ${pref} from content is not allowed.`;
}
let valueType = typeof value;
if (!kPrefTypeMap.has(valueType)) {
return `Can't set pref ${pref} to value of type ${valueType}.`;
}
let prefType = Services.prefs.getPrefType(pref);
if (prefType != Services.prefs.PREF_INVALID &&
prefType != kPrefTypeMap.get(valueType)) {
return `Can't set pref ${pref} to a value with type ${valueType} that doesn't match the pref's type ${prefType}.`;
}
return false;
}
var AsyncPrefs;
if (kInChildProcess) {
let gUniqueId = 0;
let gMsgMap = new Map();
AsyncPrefs = {
set: Task.async(function(pref, value) {
let error = maybeReturnErrorForSet(pref, value);
if (error) {
return Promise.reject(error);
}
let msgId = ++gUniqueId;
return new Promise((resolve, reject) => {
gMsgMap.set(msgId, {resolve, reject});
Services.cpmm.sendAsyncMessage("AsyncPrefs:SetPref", {pref, value, msgId});
});
}),
reset: Task.async(function(pref) {
let error = maybeReturnErrorForReset(pref);
if (error) {
return Promise.reject(error);
}
let msgId = ++gUniqueId;
return new Promise((resolve, reject) => {
gMsgMap.set(msgId, {resolve, reject});
Services.cpmm.sendAsyncMessage("AsyncPrefs:ResetPref", {pref, msgId});
});
}),
receiveMessage(msg) {
let promiseRef = gMsgMap.get(msg.data.msgId);
if (promiseRef) {
gMsgMap.delete(msg.data.msgId);
if (msg.data.success) {
promiseRef.resolve();
} else {
promiseRef.reject(msg.data.message);
}
}
},
init() {
Services.cpmm.addMessageListener("AsyncPrefs:PrefSetFinished", this);
Services.cpmm.addMessageListener("AsyncPrefs:PrefResetFinished", this);
},
};
} else {
AsyncPrefs = {
methodForType: {
number: "setIntPref",
boolean: "setBoolPref",
string: "setCharPref",
},
set: Task.async(function(pref, value) {
let error = maybeReturnErrorForSet(pref, value);
if (error) {
return Promise.reject(error);
}
let methodToUse = this.methodForType[typeof value];
try {
Services.prefs[methodToUse](pref, value);
return Promise.resolve(value);
} catch (ex) {
Cu.reportError(ex);
return Promise.reject(ex.message);
}
}),
reset: Task.async(function(pref) {
let error = maybeReturnErrorForReset(pref);
if (error) {
return Promise.reject(error);
}
try {
Services.prefs.clearUserPref(pref);
return Promise.resolve();
} catch (ex) {
Cu.reportError(ex);
return Promise.reject(ex.message);
}
}),
receiveMessage(msg) {
if (msg.name == "AsyncPrefs:SetPref") {
this.onPrefSet(msg);
} else {
this.onPrefReset(msg);
}
},
onPrefReset(msg) {
let {pref, msgId} = msg.data;
this.reset(pref).then(function() {
msg.target.sendAsyncMessage("AsyncPrefs:PrefResetFinished", {msgId, success: true});
}, function(msg) {
msg.target.sendAsyncMessage("AsyncPrefs:PrefResetFinished", {msgId, success: false, message: msg});
});
},
onPrefSet(msg) {
let {pref, value, msgId} = msg.data;
this.set(pref, value).then(function() {
msg.target.sendAsyncMessage("AsyncPrefs:PrefSetFinished", {msgId, success: true});
}, function(msg) {
msg.target.sendAsyncMessage("AsyncPrefs:PrefSetFinished", {msgId, success: false, message: msg});
});
},
init() {
Services.ppmm.addMessageListener("AsyncPrefs:SetPref", this);
Services.ppmm.addMessageListener("AsyncPrefs:ResetPref", this);
}
};
}
AsyncPrefs.init();