fs Add mkd subcommand for creating directories

user/fs/main.c

@@ -2,8 +2,8 @@
 #include <stddef.h>
 #include <ulib.h>
 
-extern void fs_fetch(void);
-extern void fs_mkf(void);
+#define CMDS(X) \
+  X(fetch) X(mkf) X(mkd)
 
 void main(void) {
   if (argslen() == 0) {
@@ -12,11 +12,13 @@ void main(void) {
 
   char *cmd = args()[0];
 
-  if (string_strcmp(cmd, "fetch") == 0) {
-    fs_fetch();
-  } else if (string_strcmp(cmd, "mkf") == 0) {
-    fs_mkf();
-  } else {
-    uprintf("fs: unknown command %s\n", cmd);
+  #define X(name) if (string_strcmp(cmd, #name) == 0) { \
+    extern void fs_ ## name(void); \
+    fs_ ## name(); \
+    return; \
   }
+  CMDS(X)
+  #undef X
+
+  uprintf("fs: unknown command %s\n", cmd);
 }