mirror of
https://github.com/VictoriaMetrics/VictoriaMetrics.git
synced 2024-11-23 20:37:12 +01:00
131 lines
3.6 KiB
Go
131 lines
3.6 KiB
Go
// Go support for leveled logs, analogous to https://code.google.com/p/google-glog/
|
|
//
|
|
// Copyright 2013 Google Inc. All Rights Reserved.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
// File I/O for logs.
|
|
|
|
package klog
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"os"
|
|
"path/filepath"
|
|
"strings"
|
|
"sync"
|
|
"time"
|
|
)
|
|
|
|
// MaxSize is the maximum size of a log file in bytes.
|
|
var MaxSize uint64 = 1024 * 1024 * 1800
|
|
|
|
// logDirs lists the candidate directories for new log files.
|
|
var logDirs []string
|
|
|
|
func createLogDirs() {
|
|
if logging.logDir != "" {
|
|
logDirs = append(logDirs, logging.logDir)
|
|
}
|
|
logDirs = append(logDirs, os.TempDir())
|
|
}
|
|
|
|
var (
|
|
pid = os.Getpid()
|
|
program = filepath.Base(os.Args[0])
|
|
host = "unknownhost"
|
|
userName = "unknownuser"
|
|
userNameOnce sync.Once
|
|
)
|
|
|
|
func init() {
|
|
if h, err := os.Hostname(); err == nil {
|
|
host = shortHostname(h)
|
|
}
|
|
}
|
|
|
|
// shortHostname returns its argument, truncating at the first period.
|
|
// For instance, given "www.google.com" it returns "www".
|
|
func shortHostname(hostname string) string {
|
|
if i := strings.Index(hostname, "."); i >= 0 {
|
|
return hostname[:i]
|
|
}
|
|
return hostname
|
|
}
|
|
|
|
// logName returns a new log file name containing tag, with start time t, and
|
|
// the name for the symlink for tag.
|
|
func logName(tag string, t time.Time) (name, link string) {
|
|
name = fmt.Sprintf("%s.%s.%s.log.%s.%04d%02d%02d-%02d%02d%02d.%d",
|
|
program,
|
|
host,
|
|
getUserName(),
|
|
tag,
|
|
t.Year(),
|
|
t.Month(),
|
|
t.Day(),
|
|
t.Hour(),
|
|
t.Minute(),
|
|
t.Second(),
|
|
pid)
|
|
return name, program + "." + tag
|
|
}
|
|
|
|
var onceLogDirs sync.Once
|
|
|
|
// create creates a new log file and returns the file and its filename, which
|
|
// contains tag ("INFO", "FATAL", etc.) and t. If the file is created
|
|
// successfully, create also attempts to update the symlink for that tag, ignoring
|
|
// errors.
|
|
// The startup argument indicates whether this is the initial startup of klog.
|
|
// If startup is true, existing files are opened for appending instead of truncated.
|
|
func create(tag string, t time.Time, startup bool) (f *os.File, filename string, err error) {
|
|
if logging.logFile != "" {
|
|
f, err := openOrCreate(logging.logFile, startup)
|
|
if err == nil {
|
|
return f, logging.logFile, nil
|
|
}
|
|
return nil, "", fmt.Errorf("log: unable to create log: %v", err)
|
|
}
|
|
onceLogDirs.Do(createLogDirs)
|
|
if len(logDirs) == 0 {
|
|
return nil, "", errors.New("log: no log dirs")
|
|
}
|
|
name, link := logName(tag, t)
|
|
var lastErr error
|
|
for _, dir := range logDirs {
|
|
fname := filepath.Join(dir, name)
|
|
f, err := openOrCreate(fname, startup)
|
|
if err == nil {
|
|
symlink := filepath.Join(dir, link)
|
|
_ = os.Remove(symlink) // ignore err
|
|
_ = os.Symlink(name, symlink) // ignore err
|
|
return f, fname, nil
|
|
}
|
|
lastErr = err
|
|
}
|
|
return nil, "", fmt.Errorf("log: cannot create log: %v", lastErr)
|
|
}
|
|
|
|
// The startup argument indicates whether this is the initial startup of klog.
|
|
// If startup is true, existing files are opened for appending instead of truncated.
|
|
func openOrCreate(name string, startup bool) (*os.File, error) {
|
|
if startup {
|
|
f, err := os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
|
|
return f, err
|
|
}
|
|
f, err := os.Create(name)
|
|
return f, err
|
|
}
|