[add] DFS file system supports device types

components/dfs/filesystems/devfs/devfs.c

@@ -186,6 +186,7 @@ int dfs_device_fs_open(struct dfs_fd *file)
             result = file->fops->open(file);
             if (result == RT_EOK || result == -RT_ENOSYS)
             {
+                file->type = FT_DEVICE;
                 return 0;
             }
         }
@@ -197,6 +198,7 @@ int dfs_device_fs_open(struct dfs_fd *file)
         if (result == RT_EOK || result == -RT_ENOSYS)
         {
             file->data = device;
+            file->type = FT_DEVICE;
             return RT_EOK;
         }
     }

components/dfs/include/dfs.h

@@ -55,6 +55,7 @@
 #define FT_SOCKET                1   /* socket file  */
 #define FT_DIRECTORY             2   /* directory    */
 #define FT_USER                  3   /* user defined */
+#define FT_DEVICE                4   /* device */
 
 /* File flags */
 #define DFS_F_OPEN              0x01000000

components/dfs/src/dfs.c

@@ -542,6 +542,7 @@ int list_fd(void)
             else if (fd->type == FT_REGULAR) rt_kprintf("%-7.7s ", "file");
             else if (fd->type == FT_SOCKET)  rt_kprintf("%-7.7s ", "socket");
             else if (fd->type == FT_USER)    rt_kprintf("%-7.7s ", "user");
+            else if (fd->type == FT_DEVICE)   rt_kprintf("%-7.7s ", "device");
             else rt_kprintf("%-8.8s ", "unknown");
             rt_kprintf("%3d ", fd->ref_count);
             rt_kprintf("%04x  ", fd->magic);