/
gzip.es
92 lines (76 loc) · 2.58 KB
/
gzip.es
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
// String compression used Firefox API.
// Based on https://gist.github.com/Endyl/c12438b6e68bbca1bab5
const CC = Components.Constructor;
const Ci = Components.interfaces;
const Cc = Components.classes;
const UncompressConverter = CC(
'@mozilla.org/streamconv;1?from=gzip&to=uncompressed',
'nsIStreamConverter',
'asyncConvertData');
const CompressConverter = CC(
'@mozilla.org/streamconv;1?from=uncompressed&to=gzip',
'nsIStreamConverter',
'asyncConvertData');
const StringInputStream = CC(
'@mozilla.org/io/string-input-stream;1',
'nsIStringInputStream');
/**
* For request simulation
*/
function Accumulator() {
this.buffer = [];
};
Accumulator.prototype = {
buffer: null,
onStartRequest: function(aRequest, aContext) {},
onStopRequest: function(aRequest, aContext, aStatusCode) {},
onDataAvailable: function(aRequest, aContext, aInputStream, aOffset, aCount) {
var stream, input;
stream = Cc["@mozilla.org/binaryinputstream;1"].
createInstance(Ci.nsIBinaryInputStream);
stream.setInputStream(aInputStream);
input = stream.readByteArray(aCount);
this.buffer = this.buffer.concat(input);
}
};
function simulateRequest(aConverter, aStream, aContentLength) {
aConverter.onStartRequest(null, null);
aConverter.onDataAvailable(null, null, aStream, 0, aContentLength);
aConverter.onStopRequest(null, null, 201 /* 417 */);
}
function compressString(aString) {
var accumulator,
converter,
stream,
utf8String;
// Converts a Javascript string into UTF-8 encoding
// (see http://ecmanaut.blogspot.de/2006/07/encoding-decoding-utf8-in-javascript.html)
utf8String = unescape(encodeURIComponent(aString));
accumulator = new Accumulator();
converter = new CompressConverter('uncompresssed', 'gzip', accumulator, null);
stream = new StringInputStream();
stream.data = utf8String;
simulateRequest(converter, stream, utf8String.length);
return Uint8Array.from(accumulator.buffer);
}
function uncompressString(aString) {
var accumulator,
converter,
stream;
accumulator = new Accumulator();
converter = new UncompressConverter('gzip', 'uncompressed', accumulator, null);
stream = new StringInputStream();
stream.data = String.fromCharCode.apply(null, aString);
simulateRequest(converter, stream, aString.length);
return String.fromCharCode.apply(null, accumulator.buffer);
}
function compatabilityCheck() {
return Uint8Array.from !== undefined;
}
var compress = false,
decompress = false;
if (compatabilityCheck()) {
compress = compressString;
decompress = uncompressString;
}
export {compress, decompress};