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authorKali Kaneko (leap communications) <kali@leap.se>2019-01-12 18:39:45 +0100
committerRuben Pollan <meskio@sindominio.net>2019-01-17 12:30:32 +0100
commitb1247d2d0d51108c910a73891ff3116e5f032ab1 (patch)
treee9948964f0bfb1ad2df3bc7bad02aa1f41ccfbd8 /vendor/github.com/getlantern/golog/golog.go
parentefcb8312e31b5c2261b1a1e95ace55b322cfcc27 (diff)
[pkg] all your deps are vendored to us
Diffstat (limited to 'vendor/github.com/getlantern/golog/golog.go')
-rw-r--r--vendor/github.com/getlantern/golog/golog.go458
1 files changed, 458 insertions, 0 deletions
diff --git a/vendor/github.com/getlantern/golog/golog.go b/vendor/github.com/getlantern/golog/golog.go
new file mode 100644
index 0000000..143e904
--- /dev/null
+++ b/vendor/github.com/getlantern/golog/golog.go
@@ -0,0 +1,458 @@
+// Package golog implements logging functions that log errors to stderr and
+// debug messages to stdout. Trace logging is also supported.
+// Trace logs go to stdout as well, but they are only written if the program
+// is run with environment variable "TRACE=true".
+// A stack dump will be printed after the message if "PRINT_STACK=true".
+package golog
+
+import (
+ "bufio"
+ "bytes"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "log"
+ "os"
+ "path/filepath"
+ "runtime"
+ "sort"
+ "strconv"
+ "strings"
+ "sync"
+ "sync/atomic"
+
+ "github.com/getlantern/errors"
+ "github.com/getlantern/hidden"
+ "github.com/getlantern/ops"
+ "github.com/oxtoacart/bpool"
+)
+
+const (
+ // ERROR is an error Severity
+ ERROR = 500
+
+ // FATAL is an error Severity
+ FATAL = 600
+)
+
+var (
+ outs atomic.Value
+ reporters []ErrorReporter
+ reportersMutex sync.RWMutex
+
+ bufferPool = bpool.NewBufferPool(200)
+
+ onFatal atomic.Value
+)
+
+// Severity is a level of error (higher values are more severe)
+type Severity int
+
+func (s Severity) String() string {
+ switch s {
+ case ERROR:
+ return "ERROR"
+ case FATAL:
+ return "FATAL"
+ default:
+ return "UNKNOWN"
+ }
+}
+
+func init() {
+ DefaultOnFatal()
+ ResetOutputs()
+}
+
+func SetOutputs(errorOut io.Writer, debugOut io.Writer) {
+ outs.Store(&outputs{
+ ErrorOut: errorOut,
+ DebugOut: debugOut,
+ })
+}
+
+func ResetOutputs() {
+ SetOutputs(os.Stderr, os.Stdout)
+}
+
+func GetOutputs() *outputs {
+ return outs.Load().(*outputs)
+}
+
+// RegisterReporter registers the given ErrorReporter. All logged Errors are
+// sent to this reporter.
+func RegisterReporter(reporter ErrorReporter) {
+ reportersMutex.Lock()
+ reporters = append(reporters, reporter)
+ reportersMutex.Unlock()
+}
+
+// OnFatal configures golog to call the given function on any FATAL error. By
+// default, golog calls os.Exit(1) on any FATAL error.
+func OnFatal(fn func(err error)) {
+ onFatal.Store(fn)
+}
+
+// DefaultOnFatal enables the default behavior for OnFatal
+func DefaultOnFatal() {
+ onFatal.Store(func(err error) {
+ os.Exit(1)
+ })
+}
+
+type outputs struct {
+ ErrorOut io.Writer
+ DebugOut io.Writer
+}
+
+// MultiLine is an interface for arguments that support multi-line output.
+type MultiLine interface {
+ // MultiLinePrinter returns a function that can be used to print the
+ // multi-line output. The returned function writes one line to the buffer and
+ // returns true if there are more lines to write. This function does not need
+ // to take care of trailing carriage returns, golog handles that
+ // automatically.
+ MultiLinePrinter() func(buf *bytes.Buffer) bool
+}
+
+// ErrorReporter is a function to which the logger will report errors.
+// It the given error and corresponding message along with associated ops
+// context. This should return quickly as it executes on the critical code
+// path. The recommended approach is to buffer as much as possible and discard
+// new reports if the buffer becomes saturated.
+type ErrorReporter func(err error, linePrefix string, severity Severity, ctx map[string]interface{})
+
+type Logger interface {
+ // Debug logs to stdout
+ Debug(arg interface{})
+ // Debugf logs to stdout
+ Debugf(message string, args ...interface{})
+
+ // Error logs to stderr
+ Error(arg interface{}) error
+ // Errorf logs to stderr. It returns the first argument that's an error, or
+ // a new error built using fmt.Errorf if none of the arguments are errors.
+ Errorf(message string, args ...interface{}) error
+
+ // Fatal logs to stderr and then exits with status 1
+ Fatal(arg interface{})
+ // Fatalf logs to stderr and then exits with status 1
+ Fatalf(message string, args ...interface{})
+
+ // Trace logs to stderr only if TRACE=true
+ Trace(arg interface{})
+ // Tracef logs to stderr only if TRACE=true
+ Tracef(message string, args ...interface{})
+
+ // TraceOut provides access to an io.Writer to which trace information can
+ // be streamed. If running with environment variable "TRACE=true", TraceOut
+ // will point to os.Stderr, otherwise it will point to a ioutil.Discared.
+ // Each line of trace information will be prefixed with this Logger's
+ // prefix.
+ TraceOut() io.Writer
+
+ // IsTraceEnabled() indicates whether or not tracing is enabled for this
+ // logger.
+ IsTraceEnabled() bool
+
+ // AsStdLogger returns an standard logger
+ AsStdLogger() *log.Logger
+}
+
+func LoggerFor(prefix string) Logger {
+ l := &logger{
+ prefix: prefix + ": ",
+ pc: make([]uintptr, 10),
+ }
+
+ trace := os.Getenv("TRACE")
+ l.traceOn, _ = strconv.ParseBool(trace)
+ if !l.traceOn {
+ prefixes := strings.Split(trace, ",")
+ for _, p := range prefixes {
+ if prefix == strings.Trim(p, " ") {
+ l.traceOn = true
+ break
+ }
+ }
+ }
+ if l.traceOn {
+ l.traceOut = l.newTraceWriter()
+ } else {
+ l.traceOut = ioutil.Discard
+ }
+
+ printStack := os.Getenv("PRINT_STACK")
+ l.printStack, _ = strconv.ParseBool(printStack)
+
+ return l
+}
+
+type logger struct {
+ prefix string
+ traceOn bool
+ traceOut io.Writer
+ printStack bool
+ outs atomic.Value
+ pc []uintptr
+ funcForPc *runtime.Func
+}
+
+// attaches the file and line number corresponding to
+// the log message
+func (l *logger) linePrefix(skipFrames int) string {
+ runtime.Callers(skipFrames, l.pc)
+ funcForPc := runtime.FuncForPC(l.pc[0])
+ file, line := funcForPc.FileLine(l.pc[0] - 1)
+ return fmt.Sprintf("%s%s:%d ", l.prefix, filepath.Base(file), line)
+}
+
+func (l *logger) print(out io.Writer, skipFrames int, severity string, arg interface{}) string {
+ buf := bufferPool.Get()
+ defer bufferPool.Put(buf)
+
+ linePrefix := l.linePrefix(skipFrames)
+ writeHeader := func() {
+ buf.WriteString(severity)
+ buf.WriteString(" ")
+ buf.WriteString(linePrefix)
+ }
+ if arg != nil {
+ ml, isMultiline := arg.(MultiLine)
+ if !isMultiline {
+ writeHeader()
+ fmt.Fprintf(buf, "%v", arg)
+ printContext(buf, arg)
+ buf.WriteByte('\n')
+ } else {
+ mlp := ml.MultiLinePrinter()
+ first := true
+ for {
+ writeHeader()
+ more := mlp(buf)
+ if first {
+ printContext(buf, arg)
+ first = false
+ }
+ buf.WriteByte('\n')
+ if !more {
+ break
+ }
+ }
+ }
+ }
+ b := []byte(hidden.Clean(buf.String()))
+ _, err := out.Write(b)
+ if err != nil {
+ errorOnLogging(err)
+ }
+ if l.printStack {
+ l.doPrintStack()
+ }
+
+ return linePrefix
+}
+
+func (l *logger) printf(out io.Writer, skipFrames int, severity string, err error, message string, args ...interface{}) string {
+ buf := bufferPool.Get()
+ defer bufferPool.Put(buf)
+
+ linePrefix := l.linePrefix(skipFrames)
+ buf.WriteString(severity)
+ buf.WriteString(" ")
+ buf.WriteString(linePrefix)
+ fmt.Fprintf(buf, message, args...)
+ printContext(buf, err)
+ buf.WriteByte('\n')
+ b := []byte(hidden.Clean(buf.String()))
+ _, err2 := out.Write(b)
+ if err2 != nil {
+ errorOnLogging(err)
+ }
+ if l.printStack {
+ l.doPrintStack()
+ }
+ return linePrefix
+}
+
+func (l *logger) Debug(arg interface{}) {
+ l.print(GetOutputs().DebugOut, 4, "DEBUG", arg)
+}
+
+func (l *logger) Debugf(message string, args ...interface{}) {
+ l.printf(GetOutputs().DebugOut, 4, "DEBUG", nil, message, args...)
+}
+
+func (l *logger) Error(arg interface{}) error {
+ return l.errorSkipFrames(arg, 1, ERROR)
+}
+
+func (l *logger) Errorf(message string, args ...interface{}) error {
+ return l.errorSkipFrames(errors.NewOffset(1, message, args...), 1, ERROR)
+}
+
+func (l *logger) Fatal(arg interface{}) {
+ fatal(l.errorSkipFrames(arg, 1, FATAL))
+}
+
+func (l *logger) Fatalf(message string, args ...interface{}) {
+ fatal(l.errorSkipFrames(errors.NewOffset(1, message, args...), 1, FATAL))
+}
+
+func fatal(err error) {
+ fn := onFatal.Load().(func(err error))
+ fn(err)
+}
+
+func (l *logger) errorSkipFrames(arg interface{}, skipFrames int, severity Severity) error {
+ var err error
+ switch e := arg.(type) {
+ case error:
+ err = e
+ default:
+ err = fmt.Errorf("%v", e)
+ }
+ linePrefix := l.print(GetOutputs().ErrorOut, skipFrames+4, severity.String(), err)
+ return report(err, linePrefix, severity)
+}
+
+func (l *logger) Trace(arg interface{}) {
+ if l.traceOn {
+ l.print(GetOutputs().DebugOut, 4, "TRACE", arg)
+ }
+}
+
+func (l *logger) Tracef(message string, args ...interface{}) {
+ if l.traceOn {
+ l.printf(GetOutputs().DebugOut, 4, "TRACE", nil, message, args...)
+ }
+}
+
+func (l *logger) TraceOut() io.Writer {
+ return l.traceOut
+}
+
+func (l *logger) IsTraceEnabled() bool {
+ return l.traceOn
+}
+
+func (l *logger) newTraceWriter() io.Writer {
+ pr, pw := io.Pipe()
+ br := bufio.NewReader(pr)
+
+ if !l.traceOn {
+ return pw
+ }
+ go func() {
+ defer func() {
+ if err := pr.Close(); err != nil {
+ errorOnLogging(err)
+ }
+ }()
+ defer func() {
+ if err := pw.Close(); err != nil {
+ errorOnLogging(err)
+ }
+ }()
+
+ for {
+ line, err := br.ReadString('\n')
+ if err == nil {
+ // Log the line (minus the trailing newline)
+ l.print(GetOutputs().DebugOut, 6, "TRACE", line[:len(line)-1])
+ } else {
+ l.printf(GetOutputs().DebugOut, 6, "TRACE", nil, "TraceWriter closed due to unexpected error: %v", err)
+ return
+ }
+ }
+ }()
+
+ return pw
+}
+
+type errorWriter struct {
+ l *logger
+}
+
+// Write implements method of io.Writer, due to different call depth,
+// it will not log correct file and line prefix
+func (w *errorWriter) Write(p []byte) (n int, err error) {
+ s := string(p)
+ if s[len(s)-1] == '\n' {
+ s = s[:len(s)-1]
+ }
+ w.l.print(GetOutputs().ErrorOut, 6, "ERROR", s)
+ return len(p), nil
+}
+
+func (l *logger) AsStdLogger() *log.Logger {
+ return log.New(&errorWriter{l}, "", 0)
+}
+
+func (l *logger) doPrintStack() {
+ var b []byte
+ buf := bytes.NewBuffer(b)
+ for _, pc := range l.pc {
+ funcForPc := runtime.FuncForPC(pc)
+ if funcForPc == nil {
+ break
+ }
+ name := funcForPc.Name()
+ if strings.HasPrefix(name, "runtime.") {
+ break
+ }
+ file, line := funcForPc.FileLine(pc)
+ fmt.Fprintf(buf, "\t%s\t%s: %d\n", name, file, line)
+ }
+ if _, err := buf.WriteTo(os.Stderr); err != nil {
+ errorOnLogging(err)
+ }
+}
+
+func errorOnLogging(err error) {
+ fmt.Fprintf(os.Stderr, "Unable to log: %v\n", err)
+}
+
+func printContext(buf *bytes.Buffer, err interface{}) {
+ // Note - we don't include globals when printing in order to avoid polluting the text log
+ values := ops.AsMap(err, false)
+ if len(values) == 0 {
+ return
+ }
+ buf.WriteString(" [")
+ var keys []string
+ for key := range values {
+ keys = append(keys, key)
+ }
+ sort.Strings(keys)
+ for i, key := range keys {
+ value := values[key]
+ if i > 0 {
+ buf.WriteString(" ")
+ }
+ buf.WriteString(key)
+ buf.WriteString("=")
+ fmt.Fprintf(buf, "%v", value)
+ }
+ buf.WriteByte(']')
+}
+
+func report(err error, linePrefix string, severity Severity) error {
+ var reportersCopy []ErrorReporter
+ reportersMutex.RLock()
+ if len(reporters) > 0 {
+ reportersCopy = make([]ErrorReporter, len(reporters))
+ copy(reportersCopy, reporters)
+ }
+ reportersMutex.RUnlock()
+
+ if len(reportersCopy) > 0 {
+ ctx := ops.AsMap(err, true)
+ ctx["severity"] = severity.String()
+ for _, reporter := range reportersCopy {
+ // We include globals when reporting
+ reporter(err, linePrefix, severity, ctx)
+ }
+ }
+ return err
+}