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/* 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,
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: ${c}`);
}
}
// Handle a left shift, restricted to bytes.
function left(octet, shift) {
return (octet << shift) & 0xff;
}
advance();
accumulate(left(val, 3));
advance();
accumulate(val >> 2);
++rOffset;
accumulate(left(val, 6));
advance();
accumulate(left(val, 1));
advance();
accumulate(val >> 4);
++rOffset;
accumulate(left(val, 4));
advance();
accumulate(val >> 1);
++rOffset;
accumulate(left(val, 7));
advance();
accumulate(left(val, 2));
advance();
accumulate(val >> 3);
++rOffset;
accumulate(left(val, 5));
advance();
accumulate(val);
++rOffset;
}
// Our output. Define to be explicit (and maybe the compiler will be smart).
let ret = new Array(bytes);
let i = 0;
let cOff = 0;
let rOff = 0;
for (; i < blocks; ++i) {
try {
processBlock(ret, cOff, rOff);
} catch (ex) {
// Handle the detection of padding.
if (ex.message == "Done") {
break;
}
throw ex;
}
cOff += 8;
rOff += 5;
}
// Slice in case our shift overflowed to the right.
return CommonUtils.byteArrayToString(ret.slice(0, bytes));
},
/**
* Trim excess padding from a Base64 string and atob().
*
*/
safeAtoB: function safeAtoB(b64) {
let len = b64.length;
let over = len % 4;
return over ? atob(b64.substr(0, len - over)) : atob(b64);
},
/**
* Ensure that the specified value is defined in integer milliseconds since
* UNIX epoch.
*
* This throws an error if the value is not an integer, is negative, or looks
* like seconds, not milliseconds.
*
* If the value is null or 0, no exception is raised.
*
* @param value
* Value to validate.
*/
ensureMillisecondsTimestamp: function ensureMillisecondsTimestamp(value) {
if (!value) {
return;
}
if (!/^[0-9]+$/.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.getStringPref(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.setStringPref(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;
},
};
ChromeUtils.defineLazyGetter(CommonUtils, "_utf8Converter", function () {
let converter = Cc[
"@mozilla.org/intl/scriptableunicodeconverter"
].createInstance(Ci.nsIScriptableUnicodeConverter);
converter.charset = "UTF-8";
return converter;
});
ChromeUtils.defineLazyGetter(CommonUtils, "_converterService", function () {
return Cc["@mozilla.org/streamConverters;1"].getService(
Ci.nsIStreamConverterService
);
});