utils.go

package main

import (
	"fmt"
	"os"
)

// getenv is not currently used.

func getenv(key, fallback string) string {
	value := os.Getenv(key)
	if len(value) == 0 {
		return fallback
	}
	return value
}

func fnMap(vs []string, f func(string) string) []string {
	vsm := make([]string, len(vs))
	for i, v := range vs {
		vsm[i] = f(v)
	}
	return vsm
}

func quoteIdentifier(identifier string) string {
	return fmt.Sprintf("`%s`", identifier)
}

func quoteString(source string) string {
	var j int
	if len(source) == 0 {
		return ""
	}
	tempStr := source[:]
	desc := make([]byte, len(tempStr)*2)
	for i := 0; i < len(tempStr); i++ {
		flag := false
		var escape byte
		switch tempStr[i] {
		case '\r':
			flag = true
			escape = '\r'
			break
		case '\n':
			flag = true
			escape = '\n'
			break
		case '\\':
			flag = true
			escape = '\\'
			break
		case '\'':
			flag = true
			escape = '\''
			break
		case '"':
			flag = true
			escape = '"'
			break
		case '\032':
			flag = true
			escape = 'Z'
			break
		default:
		}
		if flag {
			desc[j] = '\\'
			desc[j+1] = escape
			j = j + 2
		} else {
			desc[j] = tempStr[i]
			j = j + 1
		}
	}
	return string(desc[0:j])
}

func byteCountBinary(b int64) string {
	const unit = 1024
	if b < unit {
		return fmt.Sprintf("%d B", b)
	}
	div, exp := int64(unit), 0
	for n := b / unit; n >= unit; n /= unit {
		div *= unit
		exp++
	}
	return fmt.Sprintf("%.1f %ciB", float64(b)/float64(div), "KMGTPE"[exp])
}