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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-12-23 10:11:53 +00:00
bird/lib/hash.h
Ondrej Zajicek (work) ed1a908e53 BGP: Fix memory leak in graceful restart code
Prefix and bucket tables are initialized when entering established state
but not explicitly freed when leaving it (that is handled by protocol
restart). With graceful restart, BGP may enter and leave established
state multiple times without hard protocol restart causing memory leak.
2016-11-25 11:51:38 +01:00

198 lines
5.6 KiB
C

/*
* BIRD Library -- Generic Hash Table
*
* (c) 2013 Ondrej Zajicek <santiago@crfreenet.org>
* (c) 2013 CZ.NIC z.s.p.o.
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_HASH_H_
#define _BIRD_HASH_H_
#define HASH(type) struct { type **data; uint count, order; }
#define HASH_TYPE(v) typeof(** (v).data)
#define HASH_SIZE(v) (1U << (v).order)
#define HASH_EQ(v,id,k1,k2...) (id##_EQ(k1, k2))
#define HASH_FN(v,id,key...) ((u32) (id##_FN(key)) >> (32 - (v).order))
#define HASH_INIT(v,pool,init_order) \
({ \
(v).count = 0; \
(v).order = (init_order); \
(v).data = mb_allocz(pool, HASH_SIZE(v) * sizeof(* (v).data)); \
})
#define HASH_FREE(v) \
({ \
mb_free((v).data); \
(v) = (typeof(v)){ }; \
})
#define HASH_FIND(v,id,key...) \
({ \
u32 _h = HASH_FN(v, id, key); \
HASH_TYPE(v) *_n = (v).data[_h]; \
while (_n && !HASH_EQ(v, id, id##_KEY(_n), key)) \
_n = id##_NEXT(_n); \
_n; \
})
#define HASH_INSERT(v,id,node) \
({ \
u32 _h = HASH_FN(v, id, id##_KEY((node))); \
HASH_TYPE(v) **_nn = (v).data + _h; \
id##_NEXT(node) = *_nn; \
*_nn = node; \
(v).count++; \
})
#define HASH_DO_REMOVE(v,id,_nn) \
({ \
*_nn = id##_NEXT((*_nn)); \
(v).count--; \
})
#define HASH_DELETE(v,id,key...) \
({ \
u32 _h = HASH_FN(v, id, key); \
HASH_TYPE(v) *_n, **_nn = (v).data + _h; \
\
while ((*_nn) && !HASH_EQ(v, id, id##_KEY((*_nn)), key)) \
_nn = &(id##_NEXT((*_nn))); \
\
if (_n = *_nn) \
HASH_DO_REMOVE(v,id,_nn); \
_n; \
})
#define HASH_REMOVE(v,id,node) \
({ \
u32 _h = HASH_FN(v, id, id##_KEY((node))); \
HASH_TYPE(v) *_n, **_nn = (v).data + _h; \
\
while ((*_nn) && (*_nn != (node))) \
_nn = &(id##_NEXT((*_nn))); \
\
if (_n = *_nn) \
HASH_DO_REMOVE(v,id,_nn); \
_n; \
})
#define HASH_REHASH(v,id,pool,step) \
({ \
HASH_TYPE(v) *_n, *_n2, **_od; \
uint _i, _os; \
\
_os = HASH_SIZE(v); \
_od = (v).data; \
(v).count = 0; \
(v).order += (step); \
(v).data = mb_allocz(pool, HASH_SIZE(v) * sizeof(* (v).data)); \
\
for (_i = 0; _i < _os; _i++) \
for (_n = _od[_i]; _n && (_n2 = id##_NEXT(_n), 1); _n = _n2) \
HASH_INSERT(v, id, _n); \
\
mb_free(_od); \
})
#define REHASH_LO_MARK(a,b,c,d,e,f) a
#define REHASH_HI_MARK(a,b,c,d,e,f) b
#define REHASH_LO_STEP(a,b,c,d,e,f) c
#define REHASH_HI_STEP(a,b,c,d,e,f) d
#define REHASH_LO_BOUND(a,b,c,d,e,f) e
#define REHASH_HI_BOUND(a,b,c,d,e,f) f
#define HASH_DEFINE_REHASH_FN(id,type) \
static void id##_REHASH(void *v, pool *p, int step) \
{ HASH_REHASH(* (HASH(type) *) v, id, p, step); }
#define HASH_MAY_STEP_UP(v,id,pool) HASH_MAY_STEP_UP_(v,pool, id##_REHASH, id##_PARAMS)
#define HASH_MAY_STEP_DOWN(v,id,pool) HASH_MAY_STEP_DOWN_(v,pool, id##_REHASH, id##_PARAMS)
#define HASH_MAY_RESIZE_DOWN(v,id,pool) HASH_MAY_RESIZE_DOWN_(v,pool, id##_REHASH, id##_PARAMS)
#define HASH_MAY_STEP_UP_(v,pool,rehash_fn,args) \
({ \
if (((v).count > (HASH_SIZE(v) REHASH_HI_MARK(args))) && \
((v).order < (REHASH_HI_BOUND(args)))) \
rehash_fn(&(v), pool, REHASH_HI_STEP(args)); \
})
#define HASH_MAY_STEP_DOWN_(v,pool,rehash_fn,args) \
({ \
if (((v).count < (HASH_SIZE(v) REHASH_LO_MARK(args))) && \
((v).order > (REHASH_LO_BOUND(args)))) \
rehash_fn(&(v), pool, -(REHASH_LO_STEP(args))); \
})
#define HASH_MAY_RESIZE_DOWN_(v,pool,rehash_fn,args) \
({ \
uint _o = (v).order; \
while (((v).count < ((1U << _o) REHASH_LO_MARK(args))) && \
(_o > (REHASH_LO_BOUND(args)))) \
_o -= (REHASH_LO_STEP(args)); \
if (_o < (v).order) \
rehash_fn(&(v), pool, _o - (v).order); \
})
#define HASH_INSERT2(v,id,pool,node) \
({ \
HASH_INSERT(v, id, node); \
HASH_MAY_STEP_UP(v, id, pool); \
})
#define HASH_DELETE2(v,id,pool,key...) \
({ \
HASH_TYPE(v) *_n = HASH_DELETE(v, id, key); \
if (_n) HASH_MAY_STEP_DOWN(v, id, pool); \
_n; \
})
#define HASH_REMOVE2(v,id,pool,node) \
({ \
HASH_TYPE(v) *_n = HASH_REMOVE(v, id, node); \
if (_n) HASH_MAY_STEP_DOWN(v, id, pool); \
_n; \
})
#define HASH_WALK(v,next,n) \
do { \
HASH_TYPE(v) *n; \
uint _i; \
uint _s = HASH_SIZE(v); \
for (_i = 0; _i < _s; _i++) \
for (n = (v).data[_i]; n; n = n->next)
#define HASH_WALK_END } while (0)
#define HASH_WALK_DELSAFE(v,next,n) \
do { \
HASH_TYPE(v) *n, *_next; \
uint _i; \
uint _s = HASH_SIZE(v); \
for (_i = 0; _i < _s; _i++) \
for (n = (v).data[_i]; n && (_next = n->next, 1); n = _next)
#define HASH_WALK_DELSAFE_END } while (0)
#define HASH_WALK_FILTER(v,next,n,nn) \
do { \
HASH_TYPE(v) *n, **nn; \
uint _i; \
uint _s = HASH_SIZE(v); \
for (_i = 0; _i < _s; _i++) \
for (nn = (v).data + _i; n = *nn; (*nn == n) ? (nn = &n->next) : NULL)
#define HASH_WALK_FILTER_END } while (0)
#endif