mirror of https://github.com/nealey/spongy
88 lines
1.4 KiB
Go
88 lines
1.4 KiB
Go
package logfile
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"time"
|
|
)
|
|
|
|
type Logfile struct {
|
|
file *os.File
|
|
name string
|
|
nlines int
|
|
maxlines int
|
|
}
|
|
|
|
func NewLogfile(maxlines int) (*Logfile) {
|
|
return &Logfile{nil, "", 0, maxlines}
|
|
}
|
|
|
|
func (lf *Logfile) Close() {
|
|
if lf.file != nil {
|
|
lf.writeln("EXIT")
|
|
lf.file.Close()
|
|
}
|
|
}
|
|
|
|
func (lf *Logfile) writeln(s string) error {
|
|
_, err := fmt.Fprintf(lf.file, "%d %s\n", time.Now().Unix(), s)
|
|
if err == nil {
|
|
lf.nlines += 1
|
|
}
|
|
return err
|
|
}
|
|
|
|
func (lf *Logfile) rotate() error {
|
|
fn := fmt.Sprintf("%s.log", time.Now().UTC().Format(time.RFC3339))
|
|
newf, err := os.OpenFile(fn, os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0666)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if lf.file == nil {
|
|
// Set lf.file just so we can write out NEXTLOG.
|
|
// If this fails, that's okay
|
|
lf.file, _ = os.OpenFile("current", os.O_WRONLY|os.O_APPEND, 0666)
|
|
}
|
|
|
|
if lf.file != nil {
|
|
// Note location of new log
|
|
logmsg := fmt.Sprintf(". NEXTLOG %s", fn)
|
|
lf.writeln(logmsg)
|
|
|
|
// All done with the current log
|
|
lf.file.Close()
|
|
}
|
|
|
|
// Point to new log file
|
|
lf.file = newf
|
|
|
|
// Record symlink to new log
|
|
os.Remove("current")
|
|
os.Symlink(fn, "current")
|
|
|
|
logmsg := fmt.Sprintf(". PREVLOG %s", lf.name)
|
|
lf.writeln(logmsg)
|
|
|
|
lf.name = fn
|
|
|
|
return nil
|
|
}
|
|
|
|
func (lf *Logfile) Log(s string) error {
|
|
if lf.file == nil {
|
|
lf.rotate()
|
|
}
|
|
|
|
err := lf.writeln(s)
|
|
if err == nil {
|
|
return err
|
|
}
|
|
|
|
if lf.nlines >= lf.maxlines {
|
|
return lf.rotate()
|
|
}
|
|
|
|
return nil
|
|
}
|