Import of https://github.com/ciena/voltctl at commit 40d61fbf3f910ed4017cf67c9c79e8e1f82a33a5
Change-Id: I8464c59e60d76cb8612891db3303878975b5416c
diff --git a/vendor/github.com/golang/glog/glog_file.go b/vendor/github.com/golang/glog/glog_file.go
new file mode 100644
index 0000000..65075d2
--- /dev/null
+++ b/vendor/github.com/golang/glog/glog_file.go
@@ -0,0 +1,124 @@
+// 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 glog
+
+import (
+ "errors"
+ "flag"
+ "fmt"
+ "os"
+ "os/user"
+ "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
+
+// If non-empty, overrides the choice of directory in which to write logs.
+// See createLogDirs for the full list of possible destinations.
+var logDir = flag.String("log_dir", "", "If non-empty, write log files in this directory")
+
+func createLogDirs() {
+ if *logDir != "" {
+ logDirs = append(logDirs, *logDir)
+ }
+ logDirs = append(logDirs, os.TempDir())
+}
+
+var (
+ pid = os.Getpid()
+ program = filepath.Base(os.Args[0])
+ host = "unknownhost"
+ userName = "unknownuser"
+)
+
+func init() {
+ h, err := os.Hostname()
+ if err == nil {
+ host = shortHostname(h)
+ }
+
+ current, err := user.Current()
+ if err == nil {
+ userName = current.Username
+ }
+
+ // Sanitize userName since it may contain filepath separators on Windows.
+ userName = strings.Replace(userName, `\`, "_", -1)
+}
+
+// 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,
+ userName,
+ 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.
+func create(tag string, t time.Time) (f *os.File, filename string, err error) {
+ 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 := os.Create(fname)
+ 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)
+}