You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
95 lines
2.5 KiB
95 lines
2.5 KiB
'use strict'
|
|
|
|
var bindexOf = require('buffer-indexof')
|
|
|
|
var equalSign = new Buffer('=')
|
|
|
|
module.exports = function (opts) {
|
|
var binary = opts ? opts.binary : false
|
|
var that = {}
|
|
|
|
that.encode = function (data, buf, offset) {
|
|
if (!data) data = {}
|
|
if (!offset) offset = 0
|
|
if (!buf) buf = new Buffer(that.encodingLength(data) + offset)
|
|
|
|
var oldOffset = offset
|
|
var keys = Object.keys(data)
|
|
|
|
if (keys.length === 0) {
|
|
buf[offset] = 0
|
|
offset++
|
|
}
|
|
|
|
keys.forEach(function (key) {
|
|
var val = data[key]
|
|
var oldOffset = offset
|
|
offset++
|
|
|
|
if (val === true) {
|
|
offset += buf.write(key, offset)
|
|
} else if (Buffer.isBuffer(val)) {
|
|
offset += buf.write(key + '=', offset)
|
|
var len = val.length
|
|
val.copy(buf, offset, 0, len)
|
|
offset += len
|
|
} else {
|
|
offset += buf.write(key + '=' + val, offset)
|
|
}
|
|
|
|
buf[oldOffset] = offset - oldOffset - 1
|
|
})
|
|
|
|
that.encode.bytes = offset - oldOffset
|
|
return buf
|
|
}
|
|
|
|
that.decode = function (buf, offset, len) {
|
|
if (!offset) offset = 0
|
|
if (!Number.isFinite(len)) len = buf.length
|
|
var data = {}
|
|
var oldOffset = offset
|
|
|
|
while (offset < len) {
|
|
var b = decodeBlock(buf, offset)
|
|
var i = bindexOf(b, equalSign)
|
|
offset += decodeBlock.bytes
|
|
|
|
if (b.length === 0) continue // ignore: most likely a single zero byte
|
|
if (i === -1) data[b.toString().toLowerCase()] = true
|
|
else if (i === 0) continue // ignore: invalid key-length
|
|
else {
|
|
var key = b.slice(0, i).toString().toLowerCase()
|
|
if (key in data) continue // ignore: overwriting not allowed
|
|
data[key] = binary ? b.slice(i + 1) : b.slice(i + 1).toString()
|
|
}
|
|
}
|
|
|
|
that.decode.bytes = offset - oldOffset
|
|
return data
|
|
}
|
|
|
|
that.encodingLength = function (data) {
|
|
if (!data) return 1 // 1 byte (single empty byte)
|
|
var keys = Object.keys(data)
|
|
if (keys.length === 0) return 1 // 1 byte (single empty byte)
|
|
return keys.reduce(function (total, key) {
|
|
var val = data[key]
|
|
total += Buffer.byteLength(key) + 1 // +1 byte to store field length
|
|
if (Buffer.isBuffer(val)) total += val.length + 1 // +1 byte to fit equal sign
|
|
else if (val !== true) total += Buffer.byteLength(String(val)) + 1 // +1 byte to fit equal sign
|
|
return total
|
|
}, 0)
|
|
}
|
|
|
|
return that
|
|
}
|
|
|
|
function decodeBlock (buf, offset) {
|
|
var len = buf[offset]
|
|
var to = offset + 1 + len
|
|
var b = buf.slice(offset + 1, to > buf.length ? buf.length : to)
|
|
decodeBlock.bytes = len + 1
|
|
return b
|
|
}
|