`--block-fd` does not work

I'm having issues getting --block-fd to work. It's not actually blocking the sandbox in any way I've tried.
Minimal example:

bwrap --ro-bind / / --block-fd 9999 /usr/bin/sh # fd 9999 does not exist

The expectation is that the sandbox blocks, but it does not.

I do not really know C but I think the issue is in the TEMP_FAILURE_RETRY macro.
It seems to only loop when the given expression (read in this case) exits with EINTR, which seems inappropiate here.

bubblewrap/bubblewrap.c

Lines 47 to 54 in 8e51677

    
           #ifndef TEMP_FAILURE_RETRY 
        
           #define TEMP_FAILURE_RETRY(expression) \ 
        
             (__extension__                                                              \ 
        
               ({ long int __result;                                                     \ 
        
                  do __result = (long int) (expression);                                 \ 
        
                  while (__result == -1L && errno == EINTR);                             \ 
        
                  __result; })) 
        
           #endif

bubblewrap/bubblewrap.c

Lines 3261 to 3266 in 8e51677

    
           if (opt_block_fd != -1) 
        
             { 
        
               char b[1]; 
        
               (void) TEMP_FAILURE_RETRY (read (opt_block_fd, b, 1)); 
        
               close (opt_block_fd); 
        
             }

nvm fixed it

	#ifndef TEMP_FAILURE_RETRY
	#define TEMP_FAILURE_RETRY(expression) \
	(__extension__ \
	({ long int __result; \
	do __result = (long int) (expression); \
	while (__result == -1L && errno == EINTR); \
	__result; }))
	#endif

	if (opt_block_fd != -1)
	{
	char b[1];
	(void) TEMP_FAILURE_RETRY (read (opt_block_fd, b, 1));
	close (opt_block_fd);
	}