tools: lxc-attach: replace converting standard identifiers of namespaces to api

src/lxc/tools/lxc_attach.c

@@ -100,8 +100,6 @@ static int add_to_simple_array(char ***array, ssize_t *capacity, char *value)
 
 static int my_parser(struct lxc_arguments *args, int c, char *arg)
 {
-	char **it;
-	char *del;
 	int ret;
 
 	switch (c) {
@@ -121,32 +119,13 @@ static int my_parser(struct lxc_arguments *args, int c, char *arg)
 	case 's':
 		namespace_flags = 0;
 
-		/* The identifiers for namespaces used with lxc-attach as given
-		 * on the manpage do not align with the standard identifiers.
-		 * This affects network, mount, and uts namespaces. The standard
-		 * identifiers are: "mnt", "uts", and "net" whereas lxc-attach
-		 * uses "MOUNT", "UTSNAME", and "NETWORK". So let's use some
-		 * cheap memmove()s to replace them by their standard
-		 * identifiers. Let's illustrate this with an example:
-		 * Assume the string:
-		 *
-		 *	"IPC|MOUNT|PID"
-		 *
-		 * then we memmove()
-		 *
-		 *	dest: del + 1 == OUNT|PID
-		 *	src:  del + 3 == NT|PID
-		 */
-		while ((del = strstr(arg, "MOUNT")))
-			memmove(del + 1, del + 3, strlen(del) - 2);
-
-		for (it = (char *[]){"NETWORK", "UTSNAME", NULL}; it && *it; it++)
-			while ((del = strstr(arg, *it)))
-				memmove(del + 3, del + 7, strlen(del) - 6);
+		if (lxc_namespace_2_std_identifiers(arg) < 0)
+			return -1;
 
 		ret = lxc_fill_namespace_flags(arg, &namespace_flags);
 		if (ret)
 			return -1;
+
 		/* -s implies -e */
 		lxc_fill_elevated_privileges(NULL, &elevated_privileges);
 		break;