You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
180 lines
3.3 KiB
180 lines
3.3 KiB
package autofile
|
|
|
|
import (
|
|
"os"
|
|
"os/signal"
|
|
"sync"
|
|
"syscall"
|
|
"time"
|
|
|
|
cmn "github.com/tendermint/tendermint/libs/common"
|
|
"github.com/tendermint/tendermint/libs/errors"
|
|
)
|
|
|
|
/* AutoFile usage
|
|
|
|
// Create/Append to ./autofile_test
|
|
af, err := OpenAutoFile("autofile_test")
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
// Stream of writes.
|
|
// During this time, the file may be moved e.g. by logRotate.
|
|
for i := 0; i < 60; i++ {
|
|
af.Write([]byte(Fmt("LOOP(%v)", i)))
|
|
time.Sleep(time.Second)
|
|
}
|
|
|
|
// Close the AutoFile
|
|
err = af.Close()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
*/
|
|
|
|
const (
|
|
autoFileClosePeriod = 1000 * time.Millisecond
|
|
autoFilePerms = os.FileMode(0600)
|
|
)
|
|
|
|
// AutoFile automatically closes and re-opens file for writing. The file is
|
|
// automatically setup to close itself every 1s and upon receiving SIGHUP.
|
|
//
|
|
// This is useful for using a log file with the logrotate tool.
|
|
type AutoFile struct {
|
|
ID string
|
|
Path string
|
|
|
|
closeTicker *time.Ticker
|
|
closeTickerStopc chan struct{} // closed when closeTicker is stopped
|
|
hupc chan os.Signal
|
|
|
|
mtx sync.Mutex
|
|
file *os.File
|
|
}
|
|
|
|
// OpenAutoFile creates an AutoFile in the path (with random ID). If there is
|
|
// an error, it will be of type *PathError or *ErrPermissionsChanged (if file's
|
|
// permissions got changed (should be 0600)).
|
|
func OpenAutoFile(path string) (*AutoFile, error) {
|
|
af := &AutoFile{
|
|
ID: cmn.RandStr(12) + ":" + path,
|
|
Path: path,
|
|
closeTicker: time.NewTicker(autoFileClosePeriod),
|
|
closeTickerStopc: make(chan struct{}),
|
|
}
|
|
if err := af.openFile(); err != nil {
|
|
af.Close()
|
|
return nil, err
|
|
}
|
|
|
|
// Close file on SIGHUP.
|
|
af.hupc = make(chan os.Signal, 1)
|
|
signal.Notify(af.hupc, syscall.SIGHUP)
|
|
go func() {
|
|
for range af.hupc {
|
|
af.closeFile()
|
|
}
|
|
}()
|
|
|
|
go af.closeFileRoutine()
|
|
|
|
return af, nil
|
|
}
|
|
|
|
func (af *AutoFile) Close() error {
|
|
af.closeTicker.Stop()
|
|
close(af.closeTickerStopc)
|
|
if af.hupc != nil {
|
|
close(af.hupc)
|
|
}
|
|
return af.closeFile()
|
|
}
|
|
|
|
func (af *AutoFile) closeFileRoutine() {
|
|
for {
|
|
select {
|
|
case <-af.closeTicker.C:
|
|
af.closeFile()
|
|
case <-af.closeTickerStopc:
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func (af *AutoFile) closeFile() (err error) {
|
|
af.mtx.Lock()
|
|
defer af.mtx.Unlock()
|
|
|
|
file := af.file
|
|
if file == nil {
|
|
return nil
|
|
}
|
|
|
|
af.file = nil
|
|
return file.Close()
|
|
}
|
|
|
|
func (af *AutoFile) Write(b []byte) (n int, err error) {
|
|
af.mtx.Lock()
|
|
defer af.mtx.Unlock()
|
|
|
|
if af.file == nil {
|
|
if err = af.openFile(); err != nil {
|
|
return
|
|
}
|
|
}
|
|
|
|
n, err = af.file.Write(b)
|
|
return
|
|
}
|
|
|
|
func (af *AutoFile) Sync() error {
|
|
af.mtx.Lock()
|
|
defer af.mtx.Unlock()
|
|
|
|
if af.file == nil {
|
|
if err := af.openFile(); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return af.file.Sync()
|
|
}
|
|
|
|
func (af *AutoFile) openFile() error {
|
|
file, err := os.OpenFile(af.Path, os.O_RDWR|os.O_CREATE|os.O_APPEND, autoFilePerms)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
fileInfo, err := file.Stat()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if fileInfo.Mode() != autoFilePerms {
|
|
return errors.NewErrPermissionsChanged(file.Name(), fileInfo.Mode(), autoFilePerms)
|
|
}
|
|
af.file = file
|
|
return nil
|
|
}
|
|
|
|
func (af *AutoFile) Size() (int64, error) {
|
|
af.mtx.Lock()
|
|
defer af.mtx.Unlock()
|
|
|
|
if af.file == nil {
|
|
err := af.openFile()
|
|
if err != nil {
|
|
if err == os.ErrNotExist {
|
|
return 0, nil
|
|
}
|
|
return -1, err
|
|
}
|
|
}
|
|
stat, err := af.file.Stat()
|
|
if err != nil {
|
|
return -1, err
|
|
}
|
|
return stat.Size(), nil
|
|
|
|
}
|