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
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
/* Node.js 6.4.0 and up has full support */
var hasFullSupport = (function () {
try {
if (!Buffer.isEncoding('latin1')) {
return false
}
var buf = Buffer.alloc ? Buffer.alloc(4) : new Buffer(4)
buf.fill('ab', 'ucs2')
return (buf.toString('hex') === '61006200')
} catch (_) {
return false
}
}())
function isSingleByte (val) {
return (val.length === 1 && val.charCodeAt(0) < 256)
}
function fillWithNumber (buffer, val, start, end) {
if (start < 0 || end > buffer.length) {
throw new RangeError('Out of range index')
}
start = start >>> 0
end = end === undefined ? buffer.length : end >>> 0
if (end > start) {
buffer.fill(val, start, end)
}
return buffer
}
function fillWithBuffer (buffer, val, start, end) {
if (start < 0 || end > buffer.length) {
throw new RangeError('Out of range index')
}
if (end <= start) {
return buffer
}
start = start >>> 0
end = end === undefined ? buffer.length : end >>> 0
var pos = start
var len = val.length
while (pos <= (end - len)) {
val.copy(buffer, pos)
pos += len
}
if (pos !== end) {
val.copy(buffer, pos, 0, end - pos)
}
return buffer
}
function fill (buffer, val, start, end, encoding) {
if (hasFullSupport) {
return buffer.fill(val, start, end, encoding)
}
if (typeof val === 'number') {
return fillWithNumber(buffer, val, start, end)
}
if (typeof val === 'string') {
if (typeof start === 'string') {
encoding = start
start = 0
end = buffer.length
} else if (typeof end === 'string') {
encoding = end
end = buffer.length
}
if (encoding !== undefined && typeof encoding !== 'string') {
throw new TypeError('encoding must be a string')
}
if (encoding === 'latin1') {
encoding = 'binary'
}
if (typeof encoding === 'string' && !Buffer.isEncoding(encoding)) {
throw new TypeError('Unknown encoding: ' + encoding)
}
if (val === '') {
return fillWithNumber(buffer, 0, start, end)
}
if (isSingleByte(val)) {
return fillWithNumber(buffer, val.charCodeAt(0), start, end)
}
val = new Buffer(val, encoding)
}
if (Buffer.isBuffer(val)) {
return fillWithBuffer(buffer, val, start, end)
}
// Other values (e.g. undefined, boolean, object) results in zero-fill
return fillWithNumber(buffer, 0, start, end)
}
module.exports = fill
|
