Implement read_dir_entry () VFS op, CE add ls command

include/dir_entry.h

@@ -0,0 +1,10 @@
+#ifndef _DIR_ENTRY_H
+#define _DIR_ENTRY_H
+
+#include <path_defs.h>
+
+struct dir_entry {
+  char path[PATH_MAX];
+};
+
+#endif // _DIR_ENTRY_H

include/status.h

@@ -16,5 +16,7 @@
 #define ST_EXEC_ERROR        12
 #define ST_MOUNT_ERROR       13
 #define ST_TRY_AGAIN         14
+#define ST_NOT_DIR           15
+#define ST_DIR_NO_ENTRIES    16
 
 #endif // _M_STATUS_H

include/syscall_defs.h

@@ -22,5 +22,6 @@
 #define SYS_MAIL_RECEIVE  19
 #define SYS_GET_PROCGROUP 20
 #define SYS_GET_EXEC_PID  21
+#define SYS_READ_DIR_ENTRY 22
 
 #endif // _M_SYSCALL_DEFS_H