3 files changed, 132 insertions, 0 deletions
diff --git a/internal/tlog/log.go b/internal/tlog/log.go
new file mode 100644
index 0000000..254a207
--- /dev/null
+++ b/internal/tlog/log.go
@@ -0,0 +1,103 @@
+package tlog
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"os"
+
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+const (
+	ProgramName = "gocryptfs"
+	wpanicMsg   = "-wpanic turns this warning into a panic: "
+)
+
+// Escape sequences for terminal colors. These will be empty strings if stdout
+// is not a terminal.
+var ColorReset, ColorGrey, ColorRed, ColorGreen, ColorYellow string
+
+func JSONDump(obj interface{}) string {
+	b, err := json.MarshalIndent(obj, "", "\t")
+	if err != nil {
+		return err.Error()
+	} else {
+		return string(b)
+	}
+}
+
+// toggledLogger - a Logger than can be enabled and disabled
+type toggledLogger struct {
+	// Enable or disable output
+	Enabled bool
+	// Panic after logging a message, useful in regression tests
+	Wpanic bool
+	// Private prefix and postfix are used for coloring
+	prefix  string
+	postfix string
+
+	*log.Logger
+}
+
+func (l *toggledLogger) Printf(format string, v ...interface{}) {
+	if !l.Enabled {
+		return
+	}
+	l.Logger.Printf(l.prefix + fmt.Sprintf(format, v...) + l.postfix)
+	if l.Wpanic {
+		l.Logger.Panic(wpanicMsg + fmt.Sprintf(format, v...))
+	}
+}
+func (l *toggledLogger) Println(v ...interface{}) {
+	if !l.Enabled {
+		return
+	}
+	l.Logger.Println(l.prefix + fmt.Sprint(v...) + l.postfix)
+	if l.Wpanic {
+		l.Logger.Panic(wpanicMsg + fmt.Sprint(v...))
+	}
+}
+
+// Debug messages
+// Can be enabled by passing "-d"
+var Debug *toggledLogger
+
+// Informational message
+// Can be disabled by passing "-q"
+var Info *toggledLogger
+
+// A warning, meaning nothing serious by itself but might indicate problems.
+// Passing "-wpanic" will make this function panic after printing the message.
+var Warn *toggledLogger
+
+// Fatal error, we are about to exit
+var Fatal *toggledLogger
+
+func init() {
+	if terminal.IsTerminal(int(os.Stdout.Fd())) {
+		ColorReset = "\033[0m"
+		ColorGrey = "\033[2m"
+		ColorRed = "\033[31m"
+		ColorGreen = "\033[32m"
+		ColorYellow = "\033[33m"
+	}
+
+	Debug = &toggledLogger{
+		Logger: log.New(os.Stdout, "", 0),
+	}
+	Info = &toggledLogger{
+		Enabled: true,
+		Logger:  log.New(os.Stdout, "", 0),
+	}
+	Warn = &toggledLogger{
+		Enabled: true,
+		Logger:  log.New(os.Stderr, "", 0),
+	}
+	Fatal = &toggledLogger{
+		Enabled: true,
+		Logger:  log.New(os.Stderr, "", 0),
+		prefix:  ColorRed,
+		postfix: ColorReset,
+	}
+}
diff --git a/internal/tlog/log_go1.4.go b/internal/tlog/log_go1.4.go
new file mode 100644
index 0000000..fae0e9b
--- /dev/null
+++ b/internal/tlog/log_go1.4.go
@@ -0,0 +1,12 @@
+// +build !go1.5
+// = go 1.4 or lower
+
+package tlog
+
+import (
+	"log/syslog"
+)
+
+func (l *toggledLogger) SwitchToSyslog(p syslog.Priority) {
+	Debug.Printf("Cannot switch to syslog - need Go 1.5 or higher")
+}
diff --git a/internal/tlog/log_go1.5.go b/internal/tlog/log_go1.5.go
new file mode 100644
index 0000000..755f623
--- /dev/null
+++ b/internal/tlog/log_go1.5.go
@@ -0,0 +1,17 @@
+// +build go1.5
+// = go 1.5 or higher
+
+package tlog
+
+import (
+	"log/syslog"
+)
+
+func (l *toggledLogger) SwitchToSyslog(p syslog.Priority) {
+	w, err := syslog.New(p, ProgramName)
+	if err != nil {
+		Warn.Printf("Cannot switch 0x%02x to syslog: %v", p, err)
+	} else {
+		l.SetOutput(w)
+	}
+}