add result

lib/isc/include/isc/result.h

@@ -0,0 +1,15 @@
+
+#ifndef ISC_RESULT_H
+#define ISC_RESULT_H 1
+
+typedef unsigned int isc_result;
+
+#define ISC_R_SUCCESS			0
+#define ISC_R_NOMEMORY			1
+#define ISC_R_UNEXPECTED		0xFFFFFFFFL
+
+#define isc_result_to_text		__isc_result_to_text
+
+char *					isc_result_to_text(isc_result);
+
+#endif /* ISC_RESULT_H */

lib/isc/result.c

@@ -0,0 +1,18 @@
+
+#include <isc/result.h>
+
+#define LAST_ENTRY	ISC_R_NOMEMORY
+
+static char *text_table[LAST_ENTRY+1] = {
+	"success",
+	"out of memory"
+};
+
+char *
+isc_result_to_text(isc_result result) {
+	if (result == ISC_R_UNEXPECTED)
+		return ("unexpected error");
+	if (result > LAST_ENTRY)
+		return ("unknown result code");
+	return (text_table[result]);
+}