CSV.swift/Sources/BinaryReader.swift

148 lines
3.8 KiB
Swift

//
// BinaryReader.swift
// CSV
//
// Created by Yasuhiro Hatta on 2016/06/20.
// Copyright © 2016 yaslab. All rights reserved.
//
import Foundation
class BinaryReader {
enum Endian {
case big
case little
}
let stream: InputStream
let endian: Endian
let closeOnDeinit: Bool
init(stream: InputStream, endian: Endian = .big, closeOnDeinit: Bool = true) {
self.stream = stream
self.endian = endian
self.closeOnDeinit = closeOnDeinit
if stream.streamStatus == .notOpen {
stream.open()
}
}
deinit {
if closeOnDeinit && stream.streamStatus == .open {
stream.close()
}
}
func readUInt8() throws -> UInt8 {
// if stream.streamStatus == .Closed {
// // ObjectDisposedException
// throw NSError(domain: "", code: 0, userInfo: nil)
// }
// if stream.streamStatus == .AtEnd {
// // EndOfStreamException
// throw NSError(domain: "", code: 0, userInfo: nil)
// }
let bufferSize = 1
var buffer = [UInt8](repeating: 0, count: bufferSize)
let length = stream.read(&buffer, maxLength: bufferSize)
if length < 0 {
// IOException
throw NSError(domain: "", code: 0, userInfo: nil)
}
if length != bufferSize {
// EndOfStreamException
throw NSError(domain: "", code: 0, userInfo: nil)
}
return buffer[0]
}
func readUInt16() throws -> UInt16 {
let bufferSize = 2
var buffer = [UInt8](repeating: 0, count: bufferSize)
let length = stream.read(&buffer, maxLength: bufferSize)
if length < 0 {
// IOException
throw NSError(domain: "", code: 0, userInfo: nil)
}
if length != bufferSize {
// EndOfStreamException
throw NSError(domain: "", code: 0, userInfo: nil)
}
let tmp = UnsafeMutablePointer<UInt16>(buffer)
switch endian {
case .big:
return CFSwapInt16BigToHost(tmp[0])
case .little:
return CFSwapInt16LittleToHost(tmp[0])
}
}
func readUInt32() throws -> UInt32 {
let bufferSize = 4
var buffer = [UInt8](repeating: 0, count: bufferSize)
let length = stream.read(&buffer, maxLength: bufferSize)
if length < 0 {
// IOException
throw NSError(domain: "", code: 0, userInfo: nil)
}
if length != 4 {
// EndOfStreamException
throw NSError(domain: "", code: 0, userInfo: nil)
}
let tmp = UnsafeMutablePointer<UInt32>(buffer)
switch endian {
case .big:
return CFSwapInt32BigToHost(tmp[0])
case .little:
return CFSwapInt32LittleToHost(tmp[0])
}
}
}
extension BinaryReader {
struct UInt8Iterator: Sequence, IteratorProtocol {
let reader: BinaryReader
private init(reader: BinaryReader) {
self.reader = reader
}
mutating func next() -> UInt8? {
return try? reader.readUInt8()
}
}
func makeUInt8Iterator() -> UInt8Iterator {
return UInt8Iterator(reader: self)
}
}
extension BinaryReader {
struct UInt16Iterator: IteratorProtocol {
let reader: BinaryReader
private init(reader: BinaryReader) {
self.reader = reader
}
mutating func next() -> UInt16? {
return try? reader.readUInt16()
}
}
func makeUInt16Iterator() -> UInt16Iterator {
return UInt16Iterator(reader: self)
}
}