Merge branch 'sp/maint-fd-limit' into maint

* sp/maint-fd-limit:
  sha1_file.c: Don't retain open fds on small packs
  mingw: add minimum getrlimit() compatibility stub
  Limit file descriptors used by packs

fast-import.c

@@ -857,6 +857,7 @@ static void start_packfile(void)
 	p = xcalloc(1, sizeof(*p) + strlen(tmpfile) + 2);
 	strcpy(p->pack_name, tmpfile);
 	p->pack_fd = pack_fd;
+	p->do_not_close = 1;
 	pack_file = sha1fd(pack_fd, p->pack_name);
 
 	hdr.hdr_signature = htonl(PACK_SIGNATURE);