diff options
Diffstat (limited to '')
| -rw-r--r-- | services/common/utils.sys.mjs | 695 |
1 files changed, 695 insertions, 0 deletions
diff --git a/services/common/utils.sys.mjs b/services/common/utils.sys.mjs new file mode 100644 index 0000000000..3c7f9f9d39 --- /dev/null +++ b/services/common/utils.sys.mjs @@ -0,0 +1,695 @@ +/* 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/. */ + +import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs"; + +import { Log } from "resource://gre/modules/Log.sys.mjs"; + +export var CommonUtils = { + /* + * Set manipulation methods. These should be lifted into toolkit, or added to + * `Set` itself. + */ + + /** + * Return elements of `a` or `b`. + */ + union(a, b) { + let out = new Set(a); + for (let x of b) { + out.add(x); + } + return out; + }, + + /** + * Return elements of `a` that are not present in `b`. + */ + difference(a, b) { + let out = new Set(a); + for (let x of b) { + out.delete(x); + } + return out; + }, + + /** + * Return elements of `a` that are also in `b`. + */ + intersection(a, b) { + let out = new Set(); + for (let x of a) { + if (b.has(x)) { + out.add(x); + } + } + return out; + }, + + /** + * Return true if `a` and `b` are the same size, and + * every element of `a` is in `b`. + */ + setEqual(a, b) { + if (a.size != b.size) { + return false; + } + for (let x of a) { + if (!b.has(x)) { + return false; + } + } + return true; + }, + + /** + * Checks elements in two arrays for equality, as determined by the `===` + * operator. This function does not perform a deep comparison; see Sync's + * `Util.deepEquals` for that. + */ + arrayEqual(a, b) { + if (a.length !== b.length) { + return false; + } + for (let i = 0; i < a.length; i++) { + if (a[i] !== b[i]) { + return false; + } + } + return true; + }, + + /** + * Encode byte string as base64URL (RFC 4648). + * + * @param bytes + * (string) Raw byte string to encode. + * @param pad + * (bool) Whether to include padding characters (=). Defaults + * to true for historical reasons. + */ + encodeBase64URL: function encodeBase64URL(bytes, pad = true) { + let s = btoa(bytes).replace(/\+/g, "-").replace(/\//g, "_"); + + if (!pad) { + return s.replace(/=+$/, ""); + } + + return s; + }, + + /** + * Create a nsIURI instance from a string. + */ + makeURI: function makeURI(URIString) { + if (!URIString) { + return null; + } + try { + return Services.io.newURI(URIString); + } catch (e) { + let log = Log.repository.getLogger("Common.Utils"); + log.debug("Could not create URI", e); + return null; + } + }, + + /** + * Execute a function on the next event loop tick. + * + * @param callback + * Function to invoke. + * @param thisObj [optional] + * Object to bind the callback to. + */ + nextTick: function nextTick(callback, thisObj) { + if (thisObj) { + callback = callback.bind(thisObj); + } + Services.tm.dispatchToMainThread(callback); + }, + + /** + * Return a timer that is scheduled to call the callback after waiting the + * provided time or as soon as possible. The timer will be set as a property + * of the provided object with the given timer name. + */ + namedTimer: function namedTimer(callback, wait, thisObj, name) { + if (!thisObj || !name) { + throw new Error( + "You must provide both an object and a property name for the timer!" + ); + } + + // Delay an existing timer if it exists + if (name in thisObj && thisObj[name] instanceof Ci.nsITimer) { + thisObj[name].delay = wait; + return thisObj[name]; + } + + // Create a special timer that we can add extra properties + let timer = Object.create( + Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer) + ); + + // Provide an easy way to clear out the timer + timer.clear = function () { + thisObj[name] = null; + timer.cancel(); + }; + + // Initialize the timer with a smart callback + timer.initWithCallback( + { + notify: function notify() { + // Clear out the timer once it's been triggered + timer.clear(); + callback.call(thisObj, timer); + }, + }, + wait, + timer.TYPE_ONE_SHOT + ); + + return (thisObj[name] = timer); + }, + + encodeUTF8: function encodeUTF8(str) { + try { + str = this._utf8Converter.ConvertFromUnicode(str); + return str + this._utf8Converter.Finish(); + } catch (ex) { + return null; + } + }, + + decodeUTF8: function decodeUTF8(str) { + try { + str = this._utf8Converter.ConvertToUnicode(str); + return str + this._utf8Converter.Finish(); + } catch (ex) { + return null; + } + }, + + byteArrayToString: function byteArrayToString(bytes) { + return bytes.map(byte => String.fromCharCode(byte)).join(""); + }, + + stringToByteArray: function stringToByteArray(bytesString) { + return Array.prototype.slice.call(bytesString).map(c => c.charCodeAt(0)); + }, + + // A lot of Util methods work with byte strings instead of ArrayBuffers. + // A patch should address this problem, but in the meantime let's provide + // helpers method to convert byte strings to Uint8Array. + byteStringToArrayBuffer(byteString) { + if (byteString === undefined) { + return new Uint8Array(); + } + const bytes = new Uint8Array(byteString.length); + for (let i = 0; i < byteString.length; ++i) { + bytes[i] = byteString.charCodeAt(i) & 0xff; + } + return bytes; + }, + + arrayBufferToByteString(buffer) { + return CommonUtils.byteArrayToString([...buffer]); + }, + + bufferToHex(buffer) { + return Array.prototype.map + .call(buffer, x => ("00" + x.toString(16)).slice(-2)) + .join(""); + }, + + bytesAsHex: function bytesAsHex(bytes) { + let s = ""; + for (let i = 0, len = bytes.length; i < len; i++) { + let c = (bytes[i].charCodeAt(0) & 0xff).toString(16); + if (c.length == 1) { + c = "0" + c; + } + s += c; + } + return s; + }, + + stringAsHex: function stringAsHex(str) { + return CommonUtils.bytesAsHex(CommonUtils.encodeUTF8(str)); + }, + + stringToBytes: function stringToBytes(str) { + return CommonUtils.hexToBytes(CommonUtils.stringAsHex(str)); + }, + + hexToBytes: function hexToBytes(str) { + let bytes = []; + for (let i = 0; i < str.length - 1; i += 2) { + bytes.push(parseInt(str.substr(i, 2), 16)); + } + return String.fromCharCode.apply(String, bytes); + }, + + hexToArrayBuffer(str) { + const octString = CommonUtils.hexToBytes(str); + return CommonUtils.byteStringToArrayBuffer(octString); + }, + + hexAsString: function hexAsString(hex) { + return CommonUtils.decodeUTF8(CommonUtils.hexToBytes(hex)); + }, + + base64urlToHex(b64str) { + return CommonUtils.bufferToHex( + new Uint8Array(ChromeUtils.base64URLDecode(b64str, { padding: "reject" })) + ); + }, + + /** + * Base32 encode (RFC 4648) a string + */ + encodeBase32: function encodeBase32(bytes) { + const key = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"; + let leftover = bytes.length % 5; + + // Pad the last quantum with zeros so the length is a multiple of 5. + if (leftover) { + for (let i = leftover; i < 5; i++) { + bytes += "\0"; + } + } + + // Chop the string into quanta of 5 bytes (40 bits). Each quantum + // is turned into 8 characters from the 32 character base. + let ret = ""; + for (let i = 0; i < bytes.length; i += 5) { + let c = Array.prototype.slice + .call(bytes.slice(i, i + 5)) + .map(byte => byte.charCodeAt(0)); + ret += + key[c[0] >> 3] + + key[((c[0] << 2) & 0x1f) | (c[1] >> 6)] + + key[(c[1] >> 1) & 0x1f] + + key[((c[1] << 4) & 0x1f) | (c[2] >> 4)] + + key[((c[2] << 1) & 0x1f) | (c[3] >> 7)] + + key[(c[3] >> 2) & 0x1f] + + key[((c[3] << 3) & 0x1f) | (c[4] >> 5)] + + key[c[4] & 0x1f]; + } + + switch (leftover) { + case 1: + return ret.slice(0, -6) + "======"; + case 2: + return ret.slice(0, -4) + "===="; + case 3: + return ret.slice(0, -3) + "==="; + case 4: + return ret.slice(0, -1) + "="; + default: + return ret; + } + }, + + /** + * Base32 decode (RFC 4648) a string. + */ + decodeBase32: function decodeBase32(str) { + const key = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"; + + let padChar = str.indexOf("="); + let chars = padChar == -1 ? str.length : padChar; + let bytes = Math.floor((chars * 5) / 8); + let blocks = Math.ceil(chars / 8); + + // Process a chunk of 5 bytes / 8 characters. + // The processing of this is known in advance, + // so avoid arithmetic! + function processBlock(ret, cOffset, rOffset) { + let c, val; + + // N.B., this relies on + // undefined | foo == foo. + function accumulate(val) { + ret[rOffset] |= val; + } + + function advance() { + c = str[cOffset++]; + if (!c || c == "" || c == "=") { + // Easier than range checking. + throw new Error("Done"); + } // Will be caught far away. + val = key.indexOf(c); + if (val == -1) { + throw new Error(`Unknown character in base32: ${c}`); + } + } + + // Handle a left shift, restricted to bytes. + function left(octet, shift) { + return (octet << shift) & 0xff; + } + + advance(); + accumulate(left(val, 3)); + advance(); + accumulate(val >> 2); + ++rOffset; + accumulate(left(val, 6)); + advance(); + accumulate(left(val, 1)); + advance(); + accumulate(val >> 4); + ++rOffset; + accumulate(left(val, 4)); + advance(); + accumulate(val >> 1); + ++rOffset; + accumulate(left(val, 7)); + advance(); + accumulate(left(val, 2)); + advance(); + accumulate(val >> 3); + ++rOffset; + accumulate(left(val, 5)); + advance(); + accumulate(val); + ++rOffset; + } + + // Our output. Define to be explicit (and maybe the compiler will be smart). + let ret = new Array(bytes); + let i = 0; + let cOff = 0; + let rOff = 0; + + for (; i < blocks; ++i) { + try { + processBlock(ret, cOff, rOff); + } catch (ex) { + // Handle the detection of padding. + if (ex.message == "Done") { + break; + } + throw ex; + } + cOff += 8; + rOff += 5; + } + + // Slice in case our shift overflowed to the right. + return CommonUtils.byteArrayToString(ret.slice(0, bytes)); + }, + + /** + * Trim excess padding from a Base64 string and atob(). + * + * See bug 562431 comment 4. + */ + safeAtoB: function safeAtoB(b64) { + let len = b64.length; + let over = len % 4; + return over ? atob(b64.substr(0, len - over)) : atob(b64); + }, + + /** + * Ensure that the specified value is defined in integer milliseconds since + * UNIX epoch. + * + * This throws an error if the value is not an integer, is negative, or looks + * like seconds, not milliseconds. + * + * If the value is null or 0, no exception is raised. + * + * @param value + * Value to validate. + */ + ensureMillisecondsTimestamp: function ensureMillisecondsTimestamp(value) { + if (!value) { + return; + } + + if (!/^[0-9]+$/.test(value)) { + throw new Error("Timestamp value is not a positive integer: " + value); + } + + let intValue = parseInt(value, 10); + + if (!intValue) { + return; + } + + // Catch what looks like seconds, not milliseconds. + if (intValue < 10000000000) { + throw new Error("Timestamp appears to be in seconds: " + intValue); + } + }, + + /** + * Read bytes from an nsIInputStream into a string. + * + * @param stream + * (nsIInputStream) Stream to read from. + * @param count + * (number) Integer number of bytes to read. If not defined, or + * 0, all available input is read. + */ + readBytesFromInputStream: function readBytesFromInputStream(stream, count) { + let BinaryInputStream = Components.Constructor( + "@mozilla.org/binaryinputstream;1", + "nsIBinaryInputStream", + "setInputStream" + ); + if (!count) { + count = stream.available(); + } + + return new BinaryInputStream(stream).readBytes(count); + }, + + /** + * Generate a new UUID using nsIUUIDGenerator. + * + * Example value: "1e00a2e2-1570-443e-bf5e-000354124234" + * + * @return string A hex-formatted UUID string. + */ + generateUUID: function generateUUID() { + let uuid = Services.uuid.generateUUID().toString(); + + return uuid.substring(1, uuid.length - 1); + }, + + /** + * Obtain an epoch value from a preference. + * + * This reads a string preference and returns an integer. The string + * preference is expected to contain the integer milliseconds since epoch. + * For best results, only read preferences that have been saved with + * setDatePref(). + * + * We need to store times as strings because integer preferences are only + * 32 bits and likely overflow most dates. + * + * If the pref contains a non-integer value, the specified default value will + * be returned. + * + * @param branch + * (Preferences) Branch from which to retrieve preference. + * @param pref + * (string) The preference to read from. + * @param def + * (Number) The default value to use if the preference is not defined. + * @param log + * (Log.Logger) Logger to write warnings to. + */ + getEpochPref: function getEpochPref(branch, pref, def = 0, log = null) { + if (!Number.isInteger(def)) { + throw new Error("Default value is not a number: " + def); + } + + let valueStr = branch.get(pref, null); + + if (valueStr !== null) { + let valueInt = parseInt(valueStr, 10); + if (Number.isNaN(valueInt)) { + if (log) { + log.warn( + "Preference value is not an integer. Using default. " + + pref + + "=" + + valueStr + + " -> " + + def + ); + } + + return def; + } + + return valueInt; + } + + return def; + }, + + /** + * Obtain a Date from a preference. + * + * This is a wrapper around getEpochPref. It converts the value to a Date + * instance and performs simple range checking. + * + * The range checking ensures the date is newer than the oldestYear + * parameter. + * + * @param branch + * (Preferences) Branch from which to read preference. + * @param pref + * (string) The preference from which to read. + * @param def + * (Number) The default value (in milliseconds) if the preference is + * not defined or invalid. + * @param log + * (Log.Logger) Logger to write warnings to. + * @param oldestYear + * (Number) Oldest year to accept in read values. + */ + getDatePref: function getDatePref( + branch, + pref, + def = 0, + log = null, + oldestYear = 2010 + ) { + let valueInt = this.getEpochPref(branch, pref, def, log); + let date = new Date(valueInt); + + if (valueInt == def || date.getFullYear() >= oldestYear) { + return date; + } + + if (log) { + log.warn( + "Unexpected old date seen in pref. Returning default: " + + pref + + "=" + + date + + " -> " + + def + ); + } + + return new Date(def); + }, + + /** + * Store a Date in a preference. + * + * This is the opposite of getDatePref(). The same notes apply. + * + * If the range check fails, an Error will be thrown instead of a default + * value silently being used. + * + * @param branch + * (Preference) Branch from which to read preference. + * @param pref + * (string) Name of preference to write to. + * @param date + * (Date) The value to save. + * @param oldestYear + * (Number) The oldest year to accept for values. + */ + setDatePref: function setDatePref(branch, pref, date, oldestYear = 2010) { + if (date.getFullYear() < oldestYear) { + throw new Error( + "Trying to set " + + pref + + " to a very old time: " + + date + + ". The current time is " + + new Date() + + ". Is the system clock wrong?" + ); + } + + branch.set(pref, "" + date.getTime()); + }, + + /** + * Convert a string between two encodings. + * + * Output is only guaranteed if the input stream is composed of octets. If + * the input string has characters with values larger than 255, data loss + * will occur. + * + * The returned string is guaranteed to consist of character codes no greater + * than 255. + * + * @param s + * (string) The source string to convert. + * @param source + * (string) The current encoding of the string. + * @param dest + * (string) The target encoding of the string. + * + * @return string + */ + convertString: function convertString(s, source, dest) { + if (!s) { + throw new Error("Input string must be defined."); + } + + let is = Cc["@mozilla.org/io/string-input-stream;1"].createInstance( + Ci.nsIStringInputStream + ); + is.setData(s, s.length); + + let listener = Cc["@mozilla.org/network/stream-loader;1"].createInstance( + Ci.nsIStreamLoader + ); + + let result; + + listener.init({ + onStreamComplete: function onStreamComplete( + loader, + context, + status, + length, + data + ) { + result = String.fromCharCode.apply(this, data); + }, + }); + + let converter = this._converterService.asyncConvertData( + source, + dest, + listener, + null + ); + converter.onStartRequest(null, null); + converter.onDataAvailable(null, is, 0, s.length); + converter.onStopRequest(null, null, null); + + return result; + }, +}; + +XPCOMUtils.defineLazyGetter(CommonUtils, "_utf8Converter", function () { + let converter = Cc[ + "@mozilla.org/intl/scriptableunicodeconverter" + ].createInstance(Ci.nsIScriptableUnicodeConverter); + converter.charset = "UTF-8"; + return converter; +}); + +XPCOMUtils.defineLazyGetter(CommonUtils, "_converterService", function () { + return Cc["@mozilla.org/streamConverters;1"].getService( + Ci.nsIStreamConverterService + ); +}); |