add log module

common/log/lua.go

@@ -0,0 +1,44 @@
+package log
+
+import (
+	"strings"
+
+	lua "github.com/yuin/gopher-lua"
+)
+
+// RegisterLua makes xray.log available to require in an LState.
+// Logging functions concatenate arguments using Lua's tostring semantics,
+// except Go errors in userdata use Error(). Messages go through the current
+// log handler.
+func RegisterLua(L *lua.LState) {
+	L.PreloadModule("xray.log", func(L *lua.LState) int {
+		module := L.NewTable()
+		for name, severity := range map[string]Severity{
+			"debug":   Severity_Debug,
+			"info":    Severity_Info,
+			"warning": Severity_Warning,
+			"error":   Severity_Error,
+		} {
+			module.RawSetString(name, L.NewFunction(func(L *lua.LState) int {
+				var content strings.Builder
+				for i := 1; i <= L.GetTop(); i++ {
+					value := L.Get(i)
+					if ud, ok := value.(*lua.LUserData); ok {
+						if err, ok := ud.Value.(error); ok {
+							content.WriteString(err.Error())
+							continue
+						}
+					}
+					content.WriteString(L.ToStringMeta(value).String())
+				}
+				Record(&GeneralMessage{
+					Severity: severity,
+					Content:  content.String(),
+				})
+				return 0
+			}))
+		}
+		L.Push(module)
+		return 1
+	})
+}