forked from emilbayes/djb2
-
Notifications
You must be signed in to change notification settings - Fork 0
/
index.js
93 lines (70 loc) · 2.06 KB
/
index.js
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
93
var assert = require('nanoassert')
var wasm = require('./djb2.js')
var mod = wasm()
var size_t = 4
var head = size_t
var freeList = []
module.exports = Djb2
function Djb2 () {
if (!(this instanceof Djb2)) return new Djb2()
if (!mod.exports) throw new Error('WASM not loaded. Wait for Djb2.ready(cb)')
if (!freeList.length) {
freeList.push(head)
head += size_t
}
this.pointer = freeList.pop()
this.finalized = false
mod.memory.fill(0, this.pointer, this.pointer + size_t)
mod.exports.djb2_init(this.pointer)
}
Djb2.prototype.ready = Djb2.ready
Djb2.prototype.update = function (input) {
assert(this.finalized === false, 'Hash instance finalized')
assert(input, 'input must be TypedArray or Buffer')
mod.memory.set(input, head)
mod.exports.djb2_update(this.pointer, head, head + input.length)
return this
}
Djb2.prototype.digest = function (enc) {
assert(this.finalized === false, 'Hash instance finalized')
this.finalized = true
freeList.push(this.pointer)
if (!enc || enc === 'binary') {
return mod.memory.slice(this.pointer, this.pointer + size_t)
}
if (enc === 'hex') {
return hexSlice(mod.memory, this.pointer, size_t)
}
assert(enc.length >= size_t, 'input must be TypedArray or Buffer')
for (var i = 0; i < size_t; i++) {
enc[i] = mod.memory[this.pointer + i]
}
return enc
}
Djb2.hash = function (input, enc) {
var pointer = head
mod.memory.set(input, head)
return mod.exports.djb2(head, head + input.length)
}
Djb2.hash_xor = function (input, enc) {
var pointer = head
mod.memory.set(input, head)
return mod.exports.djb2_xor(head, head + input.length)
}
// libsodium compat
Djb2.prototype.final = Djb2.prototype.digest
Djb2.ready = function (cb) {
if (!cb) cb = noop
if (!wasm.supported) return cb(new Error('WebAssembly not supported'))
return mod.onload(cb)
}
function noop () {}
function hexSlice (buf, start, len) {
var str = ''
for (var i = 0; i < len; i++) str += toHex(buf[start + i])
return str
}
function toHex (n) {
if (n < 16) return '0' + n.toString(16)
return n.toString(16)
}