Variable forcing now uses limited list and buffer instead of systematical instance tree traversal and in-tree "fvalue" to keep track of forced value for pointed variables (external, located). Pointer swapping is performed when forcing externals and located, with backup being restored when forcing is reset. Match Beremiz commit 93ad018fb602.
(*
* (c) 2011 Edouard Tisserant
*
* Fake semaphore support, for non preemptive implementation.
*
*)
FUNCTION_BLOCK SEMA
VAR_INPUT
CLAIM : BOOL;
RELEASE : BOOL;
END_VAR
VAR_OUTPUT
BUSY : BOOL;
END_VAR
VAR
Q_INTERNAL : BOOL;
END_VAR
Q_INTERNAL := CLAIM OR ( Q_INTERNAL AND (NOT RELEASE));
BUSY := Q_INTERNAL;
END_FUNCTION_BLOCK