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mirror of https://gitlab.nic.cz/labs/bird.git synced 2025-01-03 15:41:54 +00:00
bird/lib/hash.h
Igor Putovny f42c118aa7 Basic route aggregation
Add a new protocol offering route aggregation.

User can specify list of route attributes in the configuration file and
run route aggregation on the export side of the pipe protocol. Routes are
sorted and for every group of equivalent routes new route is created and
exported to the routing table. It is also possible to specify filter
which will run for every route before aggregation.

Furthermore, it will be possible to set attributes of new routes
according to attributes of the aggregated routes.

This is a work in progress.

Original work by Igor Putovny, subsequent cleanups and finalization by
Maria Matejka.

This is a split-commit of the neighboring aggregator branch
with a bit improved lvalue handling, to have easier merge into v3.
2023-10-31 16:40:46 +01:00

255 lines
6.5 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)
static inline void
mem_hash_init(u64 *h)
{
*h = 0x001047d54778bcafULL;
}
static inline void
mem_hash_mix(u64 *h, const void *p, uint s)
{
const u64 multiplier = 0xb38bc09a61202731ULL;
const char *pp = p;
uint i;
for (i=0; i<s/4; i++)
*h = *h * multiplier + ((const u32 *)pp)[i];
for (i=s & ~0x3; i<s; i++)
*h = *h * multiplier + pp[i];
}
static inline void
mem_hash_mix_str(u64 *h, const char *s)
{
const u64 multiplier = 0xb38bc09a61202731ULL;
while (s)
*h = *h * multiplier + *s++;
}
static inline void
mem_hash_mix_num(u64 *h, u64 val)
{
mem_hash_mix(h, &val, sizeof(val));
}
static inline uint
mem_hash_value(u64 *h)
{
return ((*h >> 32) ^ (*h & 0xffffffff));
}
static inline uint
mem_hash(const void *p, uint s)
{
static u64 h;
mem_hash_init(&h);
mem_hash_mix(&h, p, s);
return mem_hash_value(&h);
}
static inline uint
ptr_hash(const void *ptr)
{
uintptr_t p = (uintptr_t) ptr;
return p ^ (p << 8) ^ (p >> 16);
}
#endif