Fix mkcol on existing directory (#36)

Author: leoleoasd

rap.c

@@ -867,9 +867,10 @@ static ssize_t mkcol(Message * requestMessage) {
 		case ENOSPC:
 		case EDQUOT:
 			return writeErrorResponse(RAP_RESPOND_INSUFFICIENT_STORAGE, strerror(e), NULL, fileName);
+        case EEXIST:
+            return writeErrorResponse(RAP_RESPOND_METHOD_NOT_ALLOWED, strerror(e), NULL, fileName);
 		case ENOENT:
 		case EPERM:
-		case EEXIST:
 		case ENOTDIR:
 		default:
 			return writeErrorResponse(RAP_RESPOND_CONFLICT, strerror(e), NULL, fileName);

shared.h

@@ -43,6 +43,7 @@ typedef enum RapConstant {
 	RAP_RESPOND_AUTH_FAILLED = 401,
 	RAP_RESPOND_ACCESS_DENIED = 403,
 	RAP_RESPOND_NOT_FOUND = 404,
+    RAP_RESPOND_METHOD_NOT_ALLOWED = 405,
 	RAP_RESPOND_CONFLICT = 409,
 	RAP_RESPOND_URI_TOO_LARGE = 414,
 	RAP_RESPOND_LOCKED = 423,