MFC r197752:

Better glibc compatibility for getline/getdelim:

  - Tolerate applications that pass a NULL pointer for the buffer and
    claim that the capacity of the buffer is nonzero.

  - If an application passes in a non-NULL buffer pointer and claims the
    buffer has zero capacity, we should free (well, realloc) it
    anyway. It could have been obtained from malloc(0), so failing to
    free it would be a small memory leak.

lib/libc/stdio/getdelim.c

@@ -120,8 +120,8 @@ getdelim(char ** __restrict linep, size_t * __restrict linecapp, int delim,
 		goto error;
 	}
 
-	if (*linecapp == 0)
-		*linep = NULL;
+	if (*linep == NULL)
+		*linecapp = 0;
 
 	if (fp->_r <= 0 && __srefill(fp)) {
 		/* If fp is at EOF already, we just need space for the NUL. */