bits

Print the bits of hexadecimal integers.

bits takes one or more hexadecimal numbers, groups them into integers, and prints each bit. Non-flag arguments are processed as a byte array rather than converted to uint, thus you are not limited to your host machine's uint size with this tool and can print bits from arbitrary-length integers.

This is useful for analyzing hardware register values such as raw hex coming out of lspci -x or ipmitool, protocol fields, or any other bit-packed data. It fits somewhere between a calculator and a specialized/context-aware decoder.

Building

go build -o bits .

or install directly:

go install github.com/dhendrix/bits@latest

Examples

Print bits in a given range:

$ bits.go -s 2 aa bb -r 11:4
BE 0xaabb:
bit[11]: 1
bit[10]: 0
bit[ 9]: 1
bit[ 8]: 0
bit[ 7]: 1
bit[ 6]: 0
bit[ 5]: 1
bit[ 4]: 1

Print the value of a range you care about:

$ bits.go -s 2 ab cd -r 11:4 -v
BE 0xabcd[11:4]: 0xbc

Print value from raw hex, e.g. from lspci -x:

$ bits.go -s 2 -v -a -el 86 80 0d 46 
LE 0x8680[15:0]: 0x8086
LE 0x0d46[15:0]: 0x460d

Extract byte values from a 32-bit integer:

$ bits -r 7:0 -v 11223344
BE 0x0000000011223344[7:0]: 0x44

$ bits -r 15:8 -v 11223344
BE 0x0000000011223344[15:8]: 0x33

$ bits -a -r 15:0 -v 11223344
BE 0x0000000011223344[15:0]: 0x3344

bits will automatically zero-extend integers when necessary:

$ bits.go -s 1 0a b
BE 0x0a:
bit[ 3]: 1
bit[ 2]: 0
bit[ 1]: 1
bit[ 0]: 0

BE 0x0b:
bit[ 3]: 1
bit[ 2]: 0
bit[ 1]: 1
bit[ 0]: 1

Options

  -a, --all                Print all bits, including leading zeroes (suppressed by default)

  -e, --endianness l\|b    Endianness of input: `l/little` = LE, b/big = BE (default)

  -r, --range high:low     Inclusive range of bits to print; bit 0 is the least significant

  -s, --size <n>           Size of an integer in bytes (default: size of an int)

  -v, --value              Print hex value instead of individual bits (use with -r)

  -h, --help               Show flag help

Tests

$ go test .

License

BSD-3-Clause; see the copyright headers in the source files.