Improved logging.

log.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"bytes"
+	"os"
+	"sync"
+)
+
+type logTarget struct {
+	mu       sync.Mutex
+	logfn    string
+	file     *os.File
+	memLog   *bytes.Buffer
+}
+
+var LogTarget logTarget
+
+func (target *logTarget) Write(in []byte) (int, error) {
+	target.mu.Lock()
+	defer target.mu.Unlock()
+
+	return target.file.Write(in)
+}
+
+// Open a log file for writing.
+// This method will open the file in append-only mode.
+func (target *logTarget) OpenFile(fn string) (err error) {
+	target.logfn = fn
+	target.file, err = os.OpenFile(target.logfn, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0650)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Perform a log rotation
+func (target *logTarget) Rotate() error {
+	target.mu.Lock()
+	defer target.mu.Unlock()
+
+	// Close the existing log file
+	err := target.file.Close()
+	if err != nil {
+		return err
+	}
+
+	target.file, err = os.OpenFile(target.logfn, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0650)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}