new nushell commands

bytes_and_bits.md

Introducing the bytes and the bits command.

Commands specifically made for finding and manipulating binary data. Since naming is hard, we may end up changing the name. :)

the bytes command

potential crates for bytes

• https://docs.rs/bytes/latest/bytes/
• https://github.com/cronosun/abin/
• https://github.com/Mackirac/binary_byte
• https://github.com/gmantaos/file-utils

• bytes query the bytes of a buffer

• bytes at maybe thought of like str sub-string?

  • returns the byte at a specified offset in decimal 10 or hex 0x10
  • returns the bytes in a range if specified like 1..10

• bytes index-of aka bytes contains

  • finds the index of a specified hex byte 0x10
  • finds the index of a specified byte buffer

• bytes to-str - point to decode utf-8

  • returns specified bytes as a utf-8 string

• bytes build

  • kind of like buildstring but for bytes

• bytes size aka bytes length

  • return the size of something in bytes

• bytes collect

  • collect bytes like str collect

• bytes ends-with

  • returns bool of whether a buffer ends with specified byte(s)

• bytes find-replace aka bytes replace

  • find and replace specified bytes

• bytes add

  • add specified bytes to the --start, --end, --index

• bytes remove

  • remove specified bytes from --start, --end, --index

• bytes reverse

  • reverse a buffer of bytes

• bytes starts-with

  • returns bool of whether a buffer starts with specified byte(s)

the bits command

protentional crates for bits

• https://github.com/kkayal/bitlab
• https://github.com/RustyNixieTube/bit_op
• https://github.com/niconii/twiddle
• https://github.com/gnzlbg/bitwise

• bits shl aka shift --left aka << -bitwise shift left moves bits left

• bits shr aka shift --right aka >> -bitwise shift right moves bits right

• bits rol aka rotate --left

  • bitwise shift left move a bit left and adds it to the right

• bits ror aka rotate --right

  • bitwise shift right move a bit right and adds it to the left

• bits and aka &

  • bitwise and performas logical and operation on each pair of bits

• bits or aka |

  • bitwise or performs logical or operation on each pair of bits

• bits xor aka ^

  • bitwise xor perofrms logical exclusive or operation on each pair of bits

• bits not aka ~ aka complement

  • performs logical negation on each bit

TBD - we could add later or make params or leave out and there are many more we could add

• sal - shift arithmatic left
• sar - shift arithmatic right
• rcl - rotate carry left
• rcr - rotate carry right
• shld - shift left number of bits
• shrd - shift right number of bits

I was wondering if we should use pseudo-opcodes. Maybe it's just me, but I tend to think in them :D

bits shl, bits shr, bits rol, bits ror

these are the only ones i've ever really used <<, >>, &, |, ^, and ~.

How would we define the word size/wrapping condition/endianness for the bit twiddling commands?

@sholderbach Regarding endianness, we did something like this in the nushell into binary command

fn int_to_endian(n: i64) -> Vec<u8> {
    if cfg!(target_endian = "little") {
        n.to_le_bytes().to_vec()
    } else {
        n.to_be_bytes().to_vec()
    }
}

but there's also a sort-of-wrapper also that is to_ne_bytes(). I'm hopeful that this would work.