1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/vendor/github.com/RackSec/srslog/writer.go
Alexander Morozov f2614f2107 project: use vndr for vendoring
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
2016-11-03 15:31:46 -07:00

164 lines
4.2 KiB
Go

package srslog
import (
"crypto/tls"
"strings"
"sync"
)
// A Writer is a connection to a syslog server.
type Writer struct {
sync.Mutex // guards conn
priority Priority
tag string
hostname string
network string
raddr string
tlsConfig *tls.Config
framer Framer
formatter Formatter
conn serverConn
}
// connect makes a connection to the syslog server.
// It must be called with w.mu held.
func (w *Writer) connect() (err error) {
if w.conn != nil {
// ignore err from close, it makes sense to continue anyway
w.conn.close()
w.conn = nil
}
var conn serverConn
var hostname string
dialer := w.getDialer()
conn, hostname, err = dialer.Call()
if err == nil {
w.conn = conn
w.hostname = hostname
}
return
}
// SetFormatter changes the formatter function for subsequent messages.
func (w *Writer) SetFormatter(f Formatter) {
w.formatter = f
}
// SetFramer changes the framer function for subsequent messages.
func (w *Writer) SetFramer(f Framer) {
w.framer = f
}
// Write sends a log message to the syslog daemon using the default priority
// passed into `srslog.New` or the `srslog.Dial*` functions.
func (w *Writer) Write(b []byte) (int, error) {
return w.writeAndRetry(w.priority, string(b))
}
// Close closes a connection to the syslog daemon.
func (w *Writer) Close() error {
w.Lock()
defer w.Unlock()
if w.conn != nil {
err := w.conn.close()
w.conn = nil
return err
}
return nil
}
// Emerg logs a message with severity LOG_EMERG; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Emerg(m string) (err error) {
_, err = w.writeAndRetry(LOG_EMERG, m)
return err
}
// Alert logs a message with severity LOG_ALERT; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Alert(m string) (err error) {
_, err = w.writeAndRetry(LOG_ALERT, m)
return err
}
// Crit logs a message with severity LOG_CRIT; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Crit(m string) (err error) {
_, err = w.writeAndRetry(LOG_CRIT, m)
return err
}
// Err logs a message with severity LOG_ERR; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Err(m string) (err error) {
_, err = w.writeAndRetry(LOG_ERR, m)
return err
}
// Warning logs a message with severity LOG_WARNING; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Warning(m string) (err error) {
_, err = w.writeAndRetry(LOG_WARNING, m)
return err
}
// Notice logs a message with severity LOG_NOTICE; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Notice(m string) (err error) {
_, err = w.writeAndRetry(LOG_NOTICE, m)
return err
}
// Info logs a message with severity LOG_INFO; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Info(m string) (err error) {
_, err = w.writeAndRetry(LOG_INFO, m)
return err
}
// Debug logs a message with severity LOG_DEBUG; this overrides the default
// priority passed to `srslog.New` and the `srslog.Dial*` functions.
func (w *Writer) Debug(m string) (err error) {
_, err = w.writeAndRetry(LOG_DEBUG, m)
return err
}
func (w *Writer) writeAndRetry(p Priority, s string) (int, error) {
pr := (w.priority & facilityMask) | (p & severityMask)
w.Lock()
defer w.Unlock()
if w.conn != nil {
if n, err := w.write(pr, s); err == nil {
return n, err
}
}
if err := w.connect(); err != nil {
return 0, err
}
return w.write(pr, s)
}
// write generates and writes a syslog formatted string. It formats the
// message based on the current Formatter and Framer.
func (w *Writer) write(p Priority, msg string) (int, error) {
// ensure it ends in a \n
if !strings.HasSuffix(msg, "\n") {
msg += "\n"
}
err := w.conn.writeString(w.framer, w.formatter, p, w.hostname, w.tag, msg)
if err != nil {
return 0, err
}
// Note: return the length of the input, not the number of
// bytes printed by Fprintf, because this must behave like
// an io.Writer.
return len(msg), nil
}