var Stream = require("stream")
|
var writeMethods = ["write", "end", "destroy"]
|
var readMethods = ["resume", "pause"]
|
var readEvents = ["data", "close"]
|
var slice = Array.prototype.slice
|
|
module.exports = duplex
|
|
function forEach (arr, fn) {
|
if (arr.forEach) {
|
return arr.forEach(fn)
|
}
|
|
for (var i = 0; i < arr.length; i++) {
|
fn(arr[i], i)
|
}
|
}
|
|
function duplex(writer, reader) {
|
var stream = new Stream()
|
var ended = false
|
|
forEach(writeMethods, proxyWriter)
|
|
forEach(readMethods, proxyReader)
|
|
forEach(readEvents, proxyStream)
|
|
reader.on("end", handleEnd)
|
|
writer.on("drain", function() {
|
stream.emit("drain")
|
})
|
|
writer.on("error", reemit)
|
reader.on("error", reemit)
|
|
stream.writable = writer.writable
|
stream.readable = reader.readable
|
|
return stream
|
|
function proxyWriter(methodName) {
|
stream[methodName] = method
|
|
function method() {
|
return writer[methodName].apply(writer, arguments)
|
}
|
}
|
|
function proxyReader(methodName) {
|
stream[methodName] = method
|
|
function method() {
|
stream.emit(methodName)
|
var func = reader[methodName]
|
if (func) {
|
return func.apply(reader, arguments)
|
}
|
reader.emit(methodName)
|
}
|
}
|
|
function proxyStream(methodName) {
|
reader.on(methodName, reemit)
|
|
function reemit() {
|
var args = slice.call(arguments)
|
args.unshift(methodName)
|
stream.emit.apply(stream, args)
|
}
|
}
|
|
function handleEnd() {
|
if (ended) {
|
return
|
}
|
ended = true
|
var args = slice.call(arguments)
|
args.unshift("end")
|
stream.emit.apply(stream, args)
|
}
|
|
function reemit(err) {
|
stream.emit("error", err)
|
}
|
}
|
