vendor mint

vendor/github.com/bifurcation/mint/log.go

@@ -0,0 +1,55 @@
+package mint
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strings"
+)
+
+// We use this environment variable to control logging.  It should be a
+// comma-separated list of log tags (see below) or "*" to enable all logging.
+const logConfigVar = "MINT_LOG"
+
+// Pre-defined log types
+const (
+	logTypeCrypto      = "crypto"
+	logTypeHandshake   = "handshake"
+	logTypeNegotiation = "negotiation"
+	logTypeIO          = "io"
+	logTypeFrameReader = "frame"
+	logTypeVerbose     = "verbose"
+)
+
+var (
+	logFunction = log.Printf
+	logAll      = false
+	logSettings = map[string]bool{}
+)
+
+func init() {
+	parseLogEnv(os.Environ())
+}
+
+func parseLogEnv(env []string) {
+	for _, stmt := range env {
+		if strings.HasPrefix(stmt, logConfigVar+"=") {
+			val := stmt[len(logConfigVar)+1:]
+
+			if val == "*" {
+				logAll = true
+			} else {
+				for _, t := range strings.Split(val, ",") {
+					logSettings[t] = true
+				}
+			}
+		}
+	}
+}
+
+func logf(tag string, format string, args ...interface{}) {
+	if logAll || logSettings[tag] {
+		fullFormat := fmt.Sprintf("[%s] %s", tag, format)
+		logFunction(fullFormat, args...)
+	}
+}