diff options
Diffstat (limited to 'lib/fmtutil/bitfield.go')
-rw-r--r-- | lib/fmtutil/bitfield.go | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/lib/fmtutil/bitfield.go b/lib/fmtutil/bitfield.go new file mode 100644 index 0000000..b3dbe0a --- /dev/null +++ b/lib/fmtutil/bitfield.go @@ -0,0 +1,54 @@ +// Copyright (C) 2022 Luke Shumaker <lukeshu@lukeshu.com> +// +// SPDX-License-Identifier: GPL-2.0-or-later + +package util + +import ( + "fmt" + "strings" +) + +type BitfieldFormat uint8 + +const ( + HexNone = BitfieldFormat(iota) + HexLower + HexUpper +) + +func BitfieldString[T ~uint8 | ~uint16 | ~uint32 | ~uint64](bitfield T, bitnames []string, cfg BitfieldFormat) string { + var out strings.Builder + switch cfg { + case HexNone: + // do nothing + case HexLower: + fmt.Fprintf(&out, "0x%0x(", uint64(bitfield)) + case HexUpper: + fmt.Fprintf(&out, "0x%0X(", uint64(bitfield)) + } + if bitfield == 0 { + out.WriteString("none") + } else { + rest := bitfield + first := true + for i := 0; rest != 0; i++ { + if rest&(1<<i) != 0 { + if !first { + out.WriteRune('|') + } + if i < len(bitnames) { + out.WriteString(bitnames[i]) + } else { + fmt.Fprintf(&out, "(1<<%v)", i) + } + first = false + } + rest &^= 1 << i + } + } + if cfg != HexNone { + out.WriteRune(')') + } + return out.String() +} |