haproxy/include/common/xref.h
Thierry FOURNIER 3c65b7a916 MINOR: xref: Add a new xref system
xref is used to create a relation between two elements.
Once an element is released, it breaks the relation. If the
relation is already broken, it frees the xref struct.
The pointer between two elements is a sort of refcount with
max value 1. The relation is only between two elements.
The pointer and the type of element a and b are conventional.

Note that xref is initialised from Lua files because Lua is
the only one user.
2017-09-11 18:59:40 +02:00

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C

#ifndef __XREF_H__
#define __XREF_H__
/* xref is used to create relation between two elements.
* Once an element is released, it breaks the relation. If the
* relation is already broken, it frees the xref struct.
* The pointer between two elements is sort of a refcount with
* max value 1. The relation is only between two elements.
* The pointer and the type of elements a and b are conventional.
*/
struct xref {
struct xref *peer;
};
static inline void xref_create(struct xref *xref_a, struct xref *xref_b)
{
xref_a->peer = xref_b;
xref_b->peer = xref_a;
}
static inline struct xref *xref_get_peer(struct xref *xref)
{
if (!xref->peer)
return NULL;
return xref->peer;
}
static inline void xref_disconnect(struct xref *xref)
{
if (!xref->peer)
return;
xref->peer->peer = NULL;
xref->peer = NULL;
}
#endif /* __XREF_H__ */