GT2/GT2-iOS/node_modules/binary/index.js

398 lines
10 KiB
JavaScript

var Chainsaw = require('chainsaw');
var EventEmitter = require('events').EventEmitter;
var Buffers = require('buffers');
var Vars = require('./lib/vars.js');
var Stream = require('stream').Stream;
exports = module.exports = function (bufOrEm, eventName) {
if (Buffer.isBuffer(bufOrEm)) {
return exports.parse(bufOrEm);
}
var s = exports.stream();
if (bufOrEm && bufOrEm.pipe) {
bufOrEm.pipe(s);
}
else if (bufOrEm) {
bufOrEm.on(eventName || 'data', function (buf) {
s.write(buf);
});
bufOrEm.on('end', function () {
s.end();
});
}
return s;
};
exports.stream = function (input) {
if (input) return exports.apply(null, arguments);
var pending = null;
function getBytes (bytes, cb, skip) {
pending = {
bytes : bytes,
skip : skip,
cb : function (buf) {
pending = null;
cb(buf);
},
};
dispatch();
}
var offset = null;
function dispatch () {
if (!pending) {
if (caughtEnd) done = true;
return;
}
if (typeof pending === 'function') {
pending();
}
else {
var bytes = offset + pending.bytes;
if (buffers.length >= bytes) {
var buf;
if (offset == null) {
buf = buffers.splice(0, bytes);
if (!pending.skip) {
buf = buf.slice();
}
}
else {
if (!pending.skip) {
buf = buffers.slice(offset, bytes);
}
offset = bytes;
}
if (pending.skip) {
pending.cb();
}
else {
pending.cb(buf);
}
}
}
}
function builder (saw) {
function next () { if (!done) saw.next() }
var self = words(function (bytes, cb) {
return function (name) {
getBytes(bytes, function (buf) {
vars.set(name, cb(buf));
next();
});
};
});
self.tap = function (cb) {
saw.nest(cb, vars.store);
};
self.into = function (key, cb) {
if (!vars.get(key)) vars.set(key, {});
var parent = vars;
vars = Vars(parent.get(key));
saw.nest(function () {
cb.apply(this, arguments);
this.tap(function () {
vars = parent;
});
}, vars.store);
};
self.flush = function () {
vars.store = {};
next();
};
self.loop = function (cb) {
var end = false;
saw.nest(false, function loop () {
this.vars = vars.store;
cb.call(this, function () {
end = true;
next();
}, vars.store);
this.tap(function () {
if (end) saw.next()
else loop.call(this)
}.bind(this));
}, vars.store);
};
self.buffer = function (name, bytes) {
if (typeof bytes === 'string') {
bytes = vars.get(bytes);
}
getBytes(bytes, function (buf) {
vars.set(name, buf);
next();
});
};
self.skip = function (bytes) {
if (typeof bytes === 'string') {
bytes = vars.get(bytes);
}
getBytes(bytes, function () {
next();
});
};
self.scan = function find (name, search) {
if (typeof search === 'string') {
search = new Buffer(search);
}
else if (!Buffer.isBuffer(search)) {
throw new Error('search must be a Buffer or a string');
}
var taken = 0;
pending = function () {
var pos = buffers.indexOf(search, offset + taken);
var i = pos-offset-taken;
if (pos !== -1) {
pending = null;
if (offset != null) {
vars.set(
name,
buffers.slice(offset, offset + taken + i)
);
offset += taken + i + search.length;
}
else {
vars.set(
name,
buffers.slice(0, taken + i)
);
buffers.splice(0, taken + i + search.length);
}
next();
dispatch();
} else {
i = Math.max(buffers.length - search.length - offset - taken, 0);
}
taken += i;
};
dispatch();
};
self.peek = function (cb) {
offset = 0;
saw.nest(function () {
cb.call(this, vars.store);
this.tap(function () {
offset = null;
});
});
};
return self;
};
var stream = Chainsaw.light(builder);
stream.writable = true;
var buffers = Buffers();
stream.write = function (buf) {
buffers.push(buf);
dispatch();
};
var vars = Vars();
var done = false, caughtEnd = false;
stream.end = function () {
caughtEnd = true;
};
stream.pipe = Stream.prototype.pipe;
Object.getOwnPropertyNames(EventEmitter.prototype).forEach(function (name) {
stream[name] = EventEmitter.prototype[name];
});
return stream;
};
exports.parse = function parse (buffer) {
var self = words(function (bytes, cb) {
return function (name) {
if (offset + bytes <= buffer.length) {
var buf = buffer.slice(offset, offset + bytes);
offset += bytes;
vars.set(name, cb(buf));
}
else {
vars.set(name, null);
}
return self;
};
});
var offset = 0;
var vars = Vars();
self.vars = vars.store;
self.tap = function (cb) {
cb.call(self, vars.store);
return self;
};
self.into = function (key, cb) {
if (!vars.get(key)) {
vars.set(key, {});
}
var parent = vars;
vars = Vars(parent.get(key));
cb.call(self, vars.store);
vars = parent;
return self;
};
self.loop = function (cb) {
var end = false;
var ender = function () { end = true };
while (end === false) {
cb.call(self, ender, vars.store);
}
return self;
};
self.buffer = function (name, size) {
if (typeof size === 'string') {
size = vars.get(size);
}
var buf = buffer.slice(offset, Math.min(buffer.length, offset + size));
offset += size;
vars.set(name, buf);
return self;
};
self.skip = function (bytes) {
if (typeof bytes === 'string') {
bytes = vars.get(bytes);
}
offset += bytes;
return self;
};
self.scan = function (name, search) {
if (typeof search === 'string') {
search = new Buffer(search);
}
else if (!Buffer.isBuffer(search)) {
throw new Error('search must be a Buffer or a string');
}
vars.set(name, null);
// simple but slow string search
for (var i = 0; i + offset <= buffer.length - search.length + 1; i++) {
for (
var j = 0;
j < search.length && buffer[offset+i+j] === search[j];
j++
);
if (j === search.length) break;
}
vars.set(name, buffer.slice(offset, offset + i));
offset += i + search.length;
return self;
};
self.peek = function (cb) {
var was = offset;
cb.call(self, vars.store);
offset = was;
return self;
};
self.flush = function () {
vars.store = {};
return self;
};
self.eof = function () {
return offset >= buffer.length;
};
return self;
};
// convert byte strings to unsigned little endian numbers
function decodeLEu (bytes) {
var acc = 0;
for (var i = 0; i < bytes.length; i++) {
acc += Math.pow(256,i) * bytes[i];
}
return acc;
}
// convert byte strings to unsigned big endian numbers
function decodeBEu (bytes) {
var acc = 0;
for (var i = 0; i < bytes.length; i++) {
acc += Math.pow(256, bytes.length - i - 1) * bytes[i];
}
return acc;
}
// convert byte strings to signed big endian numbers
function decodeBEs (bytes) {
var val = decodeBEu(bytes);
if ((bytes[0] & 0x80) == 0x80) {
val -= Math.pow(256, bytes.length);
}
return val;
}
// convert byte strings to signed little endian numbers
function decodeLEs (bytes) {
var val = decodeLEu(bytes);
if ((bytes[bytes.length - 1] & 0x80) == 0x80) {
val -= Math.pow(256, bytes.length);
}
return val;
}
function words (decode) {
var self = {};
[ 1, 2, 4, 8 ].forEach(function (bytes) {
var bits = bytes * 8;
self['word' + bits + 'le']
= self['word' + bits + 'lu']
= decode(bytes, decodeLEu);
self['word' + bits + 'ls']
= decode(bytes, decodeLEs);
self['word' + bits + 'be']
= self['word' + bits + 'bu']
= decode(bytes, decodeBEu);
self['word' + bits + 'bs']
= decode(bytes, decodeBEs);
});
// word8be(n) == word8le(n) for all n
self.word8 = self.word8u = self.word8be;
self.word8s = self.word8bs;
return self;
}