Multiple enhancements

README.md

@@ -34,7 +34,8 @@ Code:
 ```go
 log.SetOutput(&lumberjack.Logger{
     Filename:   "/var/log/myapp/foo.log",
-    MaxSize:    500, // megabytes
+    MaxSize:    500, // megabytes (Deprecated)
+    MaxBytes:   500, // bytes
     MaxBackups: 3,
     MaxAge:     28, //days
     Compress:   true, // disabled by default
@@ -53,8 +54,13 @@ type Logger struct {
 
     // MaxSize is the maximum size in megabytes of the log file before it gets
     // rotated. It defaults to 100 megabytes.
+	// Deprecated: use MaxBytes instead.
     MaxSize int `json:"maxsize" yaml:"maxsize"`
 
+    // MaxBytes is the maximum size in bytes of the log file before it gets
+    // rotated. It defaults to 104857600 (100 megabytes).
+    MaxBytes int64 `json:"maxbytes" yaml:"maxbytes"`
+
     // MaxAge is the maximum number of days to retain old log files based on the
     // timestamp encoded in their filename.  Note that a day is defined as 24
     // hours and may not exactly correspond to calendar days due to daylight
@@ -81,13 +87,13 @@ type Logger struct {
 Logger is an io.WriteCloser that writes to the specified filename.
 
 Logger opens or creates the logfile on first Write.  If the file exists and
-is less than MaxSize megabytes, lumberjack will open and append to that file.
-If the file exists and its size is >= MaxSize megabytes, the file is renamed
+is less than MaxBytes, lumberjack will open and append to that file.
+If the file exists and its size is >= MaxBytes, the file is renamed
 by putting the current time in a timestamp in the name immediately before the
 file's extension (or the end of the filename if there's no extension). A new
 log file is then created using original filename.
 
-Whenever a write would cause the current log file exceed MaxSize megabytes,
+Whenever a write would cause the current log file exceed MaxBytes,
 the current file is closed, renamed, and a new log file created with the
 original name. Thus, the filename you give Logger is always the "current" log
 file.
@@ -163,9 +169,9 @@ go func() {
 func (l *Logger) Write(p []byte) (n int, err error)
 ```
 Write implements io.Writer.  If a write would cause the log file to be larger
-than MaxSize, the file is closed, renamed to include a timestamp of the
+than MaxBytes, the file is closed, renamed to include a timestamp of the
 current time, and a new log file is created using the original log file name.
-If the length of the write is greater than MaxSize, an error is returned.
+If the length of the write is greater than MaxBytes, an error is returned.
 
 
 

chown.go

@@ -1,3 +1,4 @@
+//go:build !linux
 // +build !linux
 
 package lumberjack

example_test.go

@@ -9,7 +9,7 @@ import (
 func Example() {
 	log.SetOutput(&Logger{
 		Filename:   "/var/log/myapp/foo.log",
-		MaxSize:    500, // megabytes
+		MaxBytes:   500, // bytes
 		MaxBackups: 3,
 		MaxAge:     28,   // days
 		Compress:   true, // disabled by default

go.mod

@@ -1,8 +1,8 @@
 module github.com/natefinch/lumberjack
 
 require (
-	github.com/BurntSushi/toml v0.3.1
-	gopkg.in/yaml.v2 v2.2.2
+	github.com/BurntSushi/toml v1.1.0
+	gopkg.in/yaml.v2 v2.4.0
 )
 
-go 1.13
+go 1.17

go.sum

@@ -1,6 +1,6 @@
-github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
-github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/BurntSushi/toml v1.1.0 h1:ksErzDEI1khOiGPgpwuI7x2ebx/uXQNw7xJpn9Eq1+I=
+github.com/BurntSushi/toml v1.1.0/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
-gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=

linux_test.go

@@ -1,3 +1,4 @@
+//go:build linux
 // +build linux
 
 package lumberjack

lumberjack.go

@@ -47,13 +47,13 @@ var _ io.WriteCloser = (*Logger)(nil)
 // Logger is an io.WriteCloser that writes to the specified filename.
 //
 // Logger opens or creates the logfile on first Write.  If the file exists and
-// is less than MaxSize megabytes, lumberjack will open and append to that file.
-// If the file exists and its size is >= MaxSize megabytes, the file is renamed
+// is less than MaxBytes, lumberjack will open and append to that file.
+// If the file exists and its size is >= MaxBytes, the file is renamed
 // by putting the current time in a timestamp in the name immediately before the
 // file's extension (or the end of the filename if there's no extension). A new
 // log file is then created using original filename.
 //
-// Whenever a write would cause the current log file exceed MaxSize megabytes,
+// Whenever a write would cause the current log file exceed MaxBytes,
 // the current file is closed, renamed, and a new log file created with the
 // original name. Thus, the filename you give Logger is always the "current" log
 // file.
@@ -82,6 +82,12 @@ type Logger struct {
 	// os.TempDir() if empty.
 	Filename string `json:"filename" yaml:"filename"`
 
+	// MaxBytes is the maximum size in bytes of the log file before it gets
+	// rotated. It defaults to 104857600 (100 megabytes).
+	MaxBytes int64 `json:"maxbytes" yaml:"maxbytes"`
+
+	// Deprecated: use MaxBytes instead.
+	// This field is mutually exclusive with the “MaxBytes” field.
 	// MaxSize is the maximum size in megabytes of the log file before it gets
 	// rotated. It defaults to 100 megabytes.
 	MaxSize int `json:"maxsize" yaml:"maxsize"`
@@ -129,17 +135,18 @@ var (
 )
 
 // Write implements io.Writer.  If a write would cause the log file to be larger
-// than MaxSize, the file is closed, renamed to include a timestamp of the
+// than MaxBytes, the file is closed, renamed to include a timestamp of the
 // current time, and a new log file is created using the original log file name.
-// If the length of the write is greater than MaxSize, an error is returned.
+// If the length of the write is greater than MaxBytes, an error is returned.
 func (l *Logger) Write(p []byte) (n int, err error) {
 	l.mu.Lock()
 	defer l.mu.Unlock()
 
 	writeLen := int64(len(p))
-	if writeLen > l.max() {
+
+	if writeLen > l.max(writeLen) {
 		return 0, fmt.Errorf(
-			"write length %d exceeds maximum file size %d", writeLen, l.max(),
+			"write length %d exceeds maximum file size %d", writeLen, l.max(writeLen),
 		)
 	}
 
@@ -149,7 +156,7 @@ func (l *Logger) Write(p []byte) (n int, err error) {
 		}
 	}
 
-	if l.size+writeLen > l.max() {
+	if l.size+writeLen > l.max(writeLen) {
 		if err := l.rotate(); err != nil {
 			return 0, err
 		}
@@ -259,8 +266,8 @@ func backupName(name string, local bool) string {
 }
 
 // openExistingOrNew opens the logfile if it exists and if the current write
-// would not put it over MaxSize.  If there is no such file or the write would
-// put it over the MaxSize, a new file is created.
+// would not put it over MaxBytes.  If there is no such file or the write would
+// put it over the MaxBytes, a new file is created.
 func (l *Logger) openExistingOrNew(writeLen int) error {
 	l.mill()
 
@@ -273,7 +280,7 @@ func (l *Logger) openExistingOrNew(writeLen int) error {
 		return fmt.Errorf("error getting log file info: %s", err)
 	}
 
-	if info.Size()+int64(writeLen) >= l.max() {
+	if info.Size()+int64(writeLen) >= l.max(int64(writeLen)) {
 		return l.rotate()
 	}
 
@@ -442,7 +449,13 @@ func (l *Logger) timeFromName(filename, prefix, ext string) (time.Time, error) {
 }
 
 // max returns the maximum size in bytes of log files before rolling.
-func (l *Logger) max() int64 {
+func (l *Logger) max(writeLen int64) int64 {
+	if l.MaxBytes != 0 {
+		if l.MaxBytes == -1 {
+			return writeLen + l.size + 1
+		}
+		return l.MaxBytes
+	}
 	if l.MaxSize == 0 {
 		return int64(defaultMaxSize * megabyte)
 	}

lumberjack_test.go

@@ -76,20 +76,19 @@ func TestOpenExisting(t *testing.T) {
 
 func TestWriteTooLong(t *testing.T) {
 	currentTime = fakeTime
-	megabyte = 1
 	dir := makeTempDir("TestWriteTooLong", t)
 	defer os.RemoveAll(dir)
 	l := &Logger{
 		Filename: logFile(dir),
-		MaxSize:  5,
+		MaxBytes: 5,
 	}
 	defer l.Close()
 	b := []byte("booooooooooooooo!")
 	n, err := l.Write(b)
 	notNil(err, t)
 	equals(0, n, t)
 	equals(err.Error(),
-		fmt.Sprintf("write length %d exceeds maximum file size %d", len(b), l.MaxSize), t)
+		fmt.Sprintf("write length %d exceeds maximum file size %d", len(b), l.MaxBytes), t)
 	_, err = os.Stat(logFile(dir))
 	assert(os.IsNotExist(err), t, "File exists, but should not have been created")
 }
@@ -137,7 +136,7 @@ func TestAutoRotate(t *testing.T) {
 	filename := logFile(dir)
 	l := &Logger{
 		Filename: filename,
-		MaxSize:  10,
+		MaxBytes: 10,
 	}
 	defer l.Close()
 	b := []byte("boo!")
@@ -174,7 +173,7 @@ func TestFirstWriteRotate(t *testing.T) {
 	filename := logFile(dir)
 	l := &Logger{
 		Filename: filename,
-		MaxSize:  10,
+		MaxBytes: 10,
 	}
 	defer l.Close()
 
@@ -205,7 +204,7 @@ func TestMaxBackups(t *testing.T) {
 	filename := logFile(dir)
 	l := &Logger{
 		Filename:   filename,
-		MaxSize:    10,
+		MaxBytes:   10,
 		MaxBackups: 1,
 	}
 	defer l.Close()
@@ -357,7 +356,7 @@ func TestCleanupExistingBackups(t *testing.T) {
 
 	l := &Logger{
 		Filename:   filename,
-		MaxSize:    10,
+		MaxBytes:   10,
 		MaxBackups: 1,
 	}
 	defer l.Close()
@@ -387,7 +386,7 @@ func TestMaxAge(t *testing.T) {
 	filename := logFile(dir)
 	l := &Logger{
 		Filename: filename,
-		MaxSize:  10,
+		MaxBytes: 10,
 		MaxAge:   1,
 	}
 	defer l.Close()
@@ -515,7 +514,7 @@ func TestLocalTime(t *testing.T) {
 
 	l := &Logger{
 		Filename:  logFile(dir),
-		MaxSize:   10,
+		MaxBytes:  10,
 		LocalTime: true,
 	}
 	defer l.Close()
@@ -543,7 +542,7 @@ func TestRotate(t *testing.T) {
 	l := &Logger{
 		Filename:   filename,
 		MaxBackups: 1,
-		MaxSize:    100, // megabytes
+		MaxBytes:   100, // megabytes
 	}
 	defer l.Close()
 	b := []byte("boo!")
@@ -601,7 +600,7 @@ func TestCompressOnRotate(t *testing.T) {
 	l := &Logger{
 		Compress: true,
 		Filename: filename,
-		MaxSize:  10,
+		MaxBytes: 10,
 	}
 	defer l.Close()
 	b := []byte("boo!")
@@ -650,7 +649,7 @@ func TestCompressOnResume(t *testing.T) {
 	l := &Logger{
 		Compress: true,
 		Filename: filename,
-		MaxSize:  10,
+		MaxBytes: 10,
 	}
 	defer l.Close()
 
@@ -692,7 +691,7 @@ func TestJson(t *testing.T) {
 	data := []byte(`
 {
 	"filename": "foo",
-	"maxsize": 5,
+	"MaxBytes": 5,
 	"maxage": 10,
 	"maxbackups": 3,
 	"localtime": true,
@@ -703,7 +702,7 @@ func TestJson(t *testing.T) {
 	err := json.Unmarshal(data, &l)
 	isNil(err, t)
 	equals("foo", l.Filename, t)
-	equals(5, l.MaxSize, t)
+	equals(int64(5), l.MaxBytes, t)
 	equals(10, l.MaxAge, t)
 	equals(3, l.MaxBackups, t)
 	equals(true, l.LocalTime, t)
@@ -713,7 +712,7 @@ func TestJson(t *testing.T) {
 func TestYaml(t *testing.T) {
 	data := []byte(`
 filename: foo
-maxsize: 5
+maxbytes: 5
 maxage: 10
 maxbackups: 3
 localtime: true
@@ -723,7 +722,7 @@ compress: true`[1:])
 	err := yaml.Unmarshal(data, &l)
 	isNil(err, t)
 	equals("foo", l.Filename, t)
-	equals(5, l.MaxSize, t)
+	equals(int64(5), l.MaxBytes, t)
 	equals(10, l.MaxAge, t)
 	equals(3, l.MaxBackups, t)
 	equals(true, l.LocalTime, t)
@@ -733,7 +732,7 @@ compress: true`[1:])
 func TestToml(t *testing.T) {
 	data := `
 filename = "foo"
-maxsize = 5
+MaxBytes = 5
 maxage = 10
 maxbackups = 3
 localtime = true
@@ -743,7 +742,7 @@ compress = true`[1:]
 	md, err := toml.Decode(data, &l)
 	isNil(err, t)
 	equals("foo", l.Filename, t)
-	equals(5, l.MaxSize, t)
+	equals(int64(5), l.MaxBytes, t)
 	equals(10, l.MaxAge, t)
 	equals(3, l.MaxBackups, t)
 	equals(true, l.LocalTime, t)

rotate_test.go

@@ -1,3 +1,4 @@
+//go:build linux
 // +build linux
 
 package lumberjack