1 files changed, 164 insertions, 0 deletions
diff --git a/pkg/k8s.io/klog/klog_file.go b/pkg/k8s.io/klog/klog_file.go
new file mode 100644
index 000000000..de830d922
--- /dev/null
+++ b/pkg/k8s.io/klog/klog_file.go
@@ -0,0 +1,164 @@
+// 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"
+	"os/user"
+	"path/filepath"
+	"runtime"
+	"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)
+	}
+}
+
+func getUserName() string {
+	userNameOnce.Do(func() {
+		// On Windows, the Go 'user' package requires netapi32.dll.
+		// This affects Windows Nano Server:
+		//   https://github.com/golang/go/issues/21867
+		// Fallback to using environment variables.
+		if runtime.GOOS == "windows" {
+			u := os.Getenv("USERNAME")
+			if len(u) == 0 {
+				return
+			}
+			// Sanitize the USERNAME since it may contain filepath separators.
+			u = strings.Replace(u, `\`, "_", -1)
+
+			// user.Current().Username normally produces something like 'USERDOMAIN\USERNAME'
+			d := os.Getenv("USERDOMAIN")
+			if len(d) != 0 {
+				userName = d + "_" + u
+			} else {
+				userName = u
+			}
+		} else {
+			current, err := user.Current()
+			if err == nil {
+				userName = current.Username
+			}
+		}
+	})
+
+	return userName
+}
+
+// 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
+}