vendor: add buildkit

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/github.com/tonistiigi/units/bytes.go

@@ -0,0 +1,125 @@
+/*
+	Simple byte size formatting.
+
+	This package implements types that can be used in stdlib formatting functions
+	like `fmt.Printf` to control the output of the expected printed string.
+
+
+	Floating point flags %f and %g print the value in using the correct unit
+	suffix. Decimal units are default, # switches to binary units. If a value is
+	best represented as full bytes, integer bytes are printed instead.
+
+		Examples:
+			fmt.Printf("%.2f", 123 * B)   => "123B"
+			fmt.Printf("%.2f", 1234 * B)  => "1.23kB"
+			fmt.Printf("%g", 1200 * B)    => "1.2kB"
+			fmt.Printf("%#g", 1024 * B)   => "1KiB"
+
+
+	Integer flag %d always prints the value in bytes. # flag adds an unit prefix.
+
+		Examples:
+			fmt.Printf("%d", 1234 * B)    => "1234"
+			fmt.Printf("%#d", 1234 * B)   => "1234B"
+
+	%v is equal to %g
+
+*/
+package units
+
+import (
+	"fmt"
+	"io"
+	"math"
+	"math/big"
+)
+
+type Bytes int64
+
+const (
+	B Bytes = 1 << (10 * iota)
+	KiB
+	MiB
+	GiB
+	TiB
+	PiB
+	EiB
+
+	KB = 1e3 * B
+	MB = 1e3 * KB
+	GB = 1e3 * MB
+	TB = 1e3 * GB
+	PB = 1e3 * TB
+	EB = 1e3 * PB
+)
+
+var units = map[bool][]string{
+	false: []string{
+		"B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB",
+	},
+	true: []string{
+		"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB",
+	},
+}
+
+func (b Bytes) Format(f fmt.State, c rune) {
+	switch c {
+	case 'f', 'g':
+		fv, unit, ok := b.floatValue(f.Flag('#'))
+		if !ok {
+			b.formatInt(&noPrecision{f}, 'd', true)
+			return
+		}
+		big.NewFloat(fv).Format(f, c)
+		io.WriteString(f, unit)
+	case 'd':
+		b.formatInt(f, c, f.Flag('#'))
+	default:
+		if f.Flag('#') {
+			fmt.Fprintf(f, "bytes(%d)", int64(b))
+		} else {
+			fmt.Fprintf(f, "%g", b)
+		}
+	}
+}
+
+func (b Bytes) formatInt(f fmt.State, c rune, withUnit bool) {
+	big.NewInt(int64(b)).Format(f, c)
+	if withUnit {
+		io.WriteString(f, "B")
+	}
+}
+
+func (b Bytes) floatValue(binary bool) (float64, string, bool) {
+	i := 0
+	var baseUnit Bytes = 1
+	if b < 0 {
+		baseUnit *= -1
+	}
+	for {
+		next := baseUnit
+		if binary {
+			next *= 1 << 10
+		} else {
+			next *= 1e3
+		}
+		if (baseUnit > 0 && b >= next) || (baseUnit < 0 && b <= next) {
+			i++
+			baseUnit = next
+			continue
+		}
+		if i == 0 {
+			return 0, "", false
+		}
+
+		return float64(b) / math.Abs(float64(baseUnit)), units[binary][i], true
+	}
+}
+
+type noPrecision struct {
+	fmt.State
+}
+
+func (*noPrecision) Precision() (prec int, ok bool) {
+	return 0, false
+}