Swiftpack.co - Package - nst/BinUtils

BinUtils

Swift functions to ease working with binary formats

Installation

Either copy BinUtils.swift into your project, or use Swift Package Manager by adding the following dependency to your Package.swift:

dependencies: [
    .Package(url: "https://github.com/nst/BinUtils.git", majorVersion: 0, minor: 1),
]

hexlify(data)

let data = "Hello".dataUsingEncoding(.utf8)!
assert(hexlify(data) == "48656C6C6F")

unhexlify(hexstr)

let s = String(data: unhexlify("48656C6C6F")!, encoding: .utf8)
assert(s == "Hello")

pack(fmt, [v1, v2, ...])

let d = pack("<h2I3sf", [1, 2, 3, "asd", 0.5])
assert(d == unhexlify("0100 02000000 03000000 617364 0000003f"))

unpack(fmt, string)

let a = unpack(">hBsf", unhexlify("0500 01 41 3fc00000")!)
assert(a[0] as? Int == 1280)
assert(a[1] as? Int == 1)
assert(a[2] as? String == "A")
assert(a[3] as? Double == 1.5)
let f = FileHandle(forReadingAtPath: "/bin/ls")!
let b = unpack("<2H", f.readDataOfLength(4))
f.closeFile()
assert(b[0] as? Int == 64207)
assert(b[1] as? Int == 65261)

caveats

pack() and unpack() should behave as Python's struct module https://docs.python.org/2/library/struct.html BUT:

  • native size and alignment @ is not supported
  • as a consequence, the byte order specifier character is mandatory and must be among =<>!
  • native byte order = assumes a little-endian system (eg. Intel x86)
  • Pascal strings p and native pointers P are not supported

Byte Order Format

| Character | Byte Order | |---|---| | = | little-endian | | < | little-endian | | > | big-endian | | ! | network (big-endian) |

Format Characters

| Format | C Type | Swift Type | Size | |---|---|---|---| | x | pad byte | - | 1 | | c | char | String of length 1 | 1 | | b | signed char | Int8 | 1 | | B | unsigned char | UInt8 | 1 | | ? | _Bool | Bool | 1 | | h | short | Int16 | 2 | | H | unsigned short | UInt16 | 2 | | i | int | Int32 | 4 | | I | unsigned int | UInt32 | 4 | | l | long | Int32 | 4 | | L | unsigned long | UInt32 | 4 | | q | long long | Int64 | 8 | | Q | unsigned long long | Int64 | 8 | | f | float | Float32 | 4 | | d | double | Float64 | 8 | | s | char[] | String | |

Github

link
Stars: 35
Help us keep the lights on

Dependencies

Used By

Total: 0