goutils/lib/lib.go

106 lines
2.6 KiB
Go
Raw Permalink Normal View History

// Package lib contains functions useful for most programs.
package lib
import (
"fmt"
"os"
"path/filepath"
"time"
)
var progname = filepath.Base(os.Args[0])
2015-10-26 23:37:44 +00:00
// ProgName returns what lib thinks the program name is, namely the
// basename of of argv0.
//
// It is similar to the Linux __progname function.
2015-10-26 23:37:44 +00:00
func ProgName() string {
return progname
}
// Warnx displays a formatted error message to standard error, à la
// warnx(3).
func Warnx(format string, a ...interface{}) (int, error) {
format = fmt.Sprintf("[%s] %s", progname, format)
format += "\n"
return fmt.Fprintf(os.Stderr, format, a...)
}
// Warn displays a formatted error message to standard output,
// appending the error string, à la warn(3).
func Warn(err error, format string, a ...interface{}) (int, error) {
format = fmt.Sprintf("[%s] %s", progname, format)
format += ": %v\n"
a = append(a, err)
return fmt.Fprintf(os.Stderr, format, a...)
}
// Errx displays a formatted error message to standard error and exits
// with the status code from `exit`, à la errx(3).
func Errx(exit int, format string, a ...interface{}) {
format = fmt.Sprintf("[%s] %s", progname, format)
format += "\n"
fmt.Fprintf(os.Stderr, format, a...)
os.Exit(exit)
}
// Err displays a formatting error message to standard error,
// appending the error string, and exits with the status code from
// `exit`, à la err(3).
func Err(exit int, err error, format string, a ...interface{}) {
format = fmt.Sprintf("[%s] %s", progname, format)
format += ": %v\n"
a = append(a, err)
fmt.Fprintf(os.Stderr, format, a...)
os.Exit(exit)
}
2015-09-22 18:25:54 +00:00
2015-09-23 05:58:58 +00:00
// Itoa provides cheap integer to fixed-width decimal ASCII. Give a
// negative width to avoid zero-padding. Adapted from the 'itoa'
// function in the log/log.go file in the standard library.
func Itoa(i int, wid int) string {
// Assemble decimal in reverse order.
var b [20]byte
bp := len(b) - 1
for i >= 10 || wid > 1 {
wid--
q := i / 10
b[bp] = byte('0' + i - q*10)
bp--
i = q
}
// i < 10
b[bp] = byte('0' + i)
return string(b[bp:])
}
var (
dayDuration = 24 * time.Hour
yearDuration = (365 * dayDuration) + (6 * time.Hour)
)
2017-10-20 19:18:41 +00:00
// Duration returns a prettier string for time.Durations.
func Duration(d time.Duration) string {
var s string
if d >= yearDuration {
years := d / yearDuration
s += fmt.Sprintf("%dy", years)
2023-05-05 06:21:07 +00:00
d -= years * yearDuration
}
if d >= dayDuration {
days := d / dayDuration
s += fmt.Sprintf("%dd", days)
}
if s != "" {
return s
}
d %= 1 * time.Second
hours := d / time.Hour
2023-05-05 06:21:07 +00:00
d -= hours * time.Hour
s += fmt.Sprintf("%dh%s", hours, d)
return s
}