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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-12-23 02:01:55 +00:00

Trie index: Finding the node relative from other node; storing the path.

Will be useful for filter trie conversion
This commit is contained in:
Maria Matejka 2019-04-17 15:34:39 +02:00
parent b7bf5c5b8d
commit 12377d33a5
3 changed files with 57 additions and 6 deletions

View File

@ -648,7 +648,7 @@ tindex_renumber(union tindex_data *idata, const struct tindex_info *tinfo, u64 o
#define TINDEX_ALLOC_IDX ({ u64 out = idm_alloc(&(ti->idm)); if (!out) goto noidx; out; }) #define TINDEX_ALLOC_IDX ({ u64 out = idm_alloc(&(ti->idm)); if (!out) goto noidx; out; })
u64 u64
tindex_find(struct tindex *ti, const uTDB *bits_in, const uint blen, const u64 create) tindex_find_rel_path(struct tindex *ti, const u64 sidx, const uTDB *bits_in, const uint blen, uint bpos, u64 *path, const u64 create)
{ {
if (blen > ti->bdepth) if (blen > ti->bdepth)
if (create) if (create)
@ -659,6 +659,8 @@ tindex_find(struct tindex *ti, const uTDB *bits_in, const uint blen, const u64 c
union tindex_data *idata = ti->index_data; union tindex_data *idata = ti->index_data;
const struct tindex_info stinfo = tindex_get_info(ti), *tinfo = &stinfo; const struct tindex_info stinfo = tindex_get_info(ti), *tinfo = &stinfo;
ASSERT(sidx > 0);
ASSERT(sidx <= tinfo->addrmask);
/* Validate unit size */ /* Validate unit size */
switch (tinfo->usize) { switch (tinfo->usize) {
@ -669,10 +671,16 @@ tindex_find(struct tindex *ti, const uTDB *bits_in, const uint blen, const u64 c
default: bug("This shall never happen"); default: bug("This shall never happen");
} }
u64 idx = 1; /* The root node is always 1 */ /* Here we begin */
u64 uidx = 0; /* Parent node is 0 on beginning */ u64 idx = sidx;
u64 uidx = tindex_up(idata, tinfo, idx);
uint bpos = 0; if (path)
memset(&(path[bpos]), 0, (blen - bpos) * sizeof(u64));
/* Shortcut for zero-length query */
if (blen == bpos)
return tindex_exists(ti->exists, idx) ? idx : 0;
while (1) { while (1) {
/* Get data from trie */ /* Get data from trie */
@ -713,6 +721,10 @@ tindex_find(struct tindex *ti, const uTDB *bits_in, const uint blen, const u64 c
return 0; return 0;
} }
/* This is not final for sure, store the path node */
if (path && tindex_exists(ti->exists, idx))
path[bpos] = idx;
/* Just one bit, to be sure */ /* Just one bit, to be sure */
ASSERT(bits < 2); ASSERT(bits < 2);
ASSERT(ilen == 1); ASSERT(ilen == 1);

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@ -20,6 +20,41 @@ struct tindex* tindex_new(pool *p);
#define TINDEX_CREATE (~(0ULL)) #define TINDEX_CREATE (~(0ULL))
#define TINDEX_FIND 0 #define TINDEX_FIND 0
/**
* Get the whole path to the indexed node at once
* @ti: the index to look into
* @sidx: index where to start
* @bits_in: data
* @blen: number of bits to extract from @bits_in.
* If @blen is not multiple of 64, the LSB's of the last u64 are ignored.
* @bpos: number of bits to ignore from @bits_in.
* @path: preallocated array of @blen of u64's to store the path.
* @create: TINDEX_FIND to find existing, TINDEX_CREATE to create new records,
* every other value is for internal use
*
* Return value: 0 for not found; nonzero = the index
*/
u64 tindex_find_rel_path(struct tindex *ti, const u64 sidx, const u32 *bits_in, const uint blen, const uint bpos, u64 *path, const u64 create);
/**
* Find an index beginning somewhere else
* @ti: the index to look into
* @sidx: index where to start
* @bits_in: data
* @blen: number of bits to extract from @bits_in.
* If @blen is not multiple of 64, the LSB's of the last u64 are ignored.
* @bpos: number of bits to ignore from @bits_in.
* @create: TINDEX_FIND to find existing, TINDEX_CREATE to create new records,
* every other value is for internal use
*
* Return value: 0 for not found; nonzero = the index
*/
static inline u64 tindex_find_rel(struct tindex *ti, const u64 sidx, const u32 *bits_in, const uint blen, uint bpos, const u64 create)
{ return tindex_find_rel_path(ti, sidx, bits_in, blen, bpos, NULL, create); }
/** /**
* Find an index * Find an index
* @ti: the tindex to look into * @ti: the tindex to look into
@ -32,7 +67,8 @@ struct tindex* tindex_new(pool *p);
* Return value: 0 for not found; nonzero = the index * Return value: 0 for not found; nonzero = the index
*/ */
u64 tindex_find(struct tindex *ti, const u32 *bits_in, const uint blen, const u64 create); static inline u64 tindex_find(struct tindex *ti, const u32 *bits_in, const uint blen, const u64 create)
{ return tindex_find_rel(ti, 1, bits_in, blen, 0, create); }
/** /**
* Delete an index. * Delete an index.

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@ -38,9 +38,12 @@ static inline void test_trie_add(struct test_trie *tt, u64 data) {
static inline void test_trie_get(struct test_trie *tt, u64 data, u64 cnt) { static inline void test_trie_get(struct test_trie *tt, u64 data, u64 cnt) {
u64 out = 0; u64 out = 0;
u32 dtb[2] = { data >> 32, data }; u32 dtb[2] = { data >> 32, data };
u64 idx = tindex_find(tt->ti, dtb, 64, TINDEX_FIND); u64 path[64] = {};
u64 idx = tindex_find_rel_path(tt->ti, 1, dtb, 64, 0, path, TINDEX_FIND);
if (idx) out = tt->data[idx]; if (idx) out = tt->data[idx];
bt_assert_msg(out == cnt, "Index %lu shall be in trie %lu times, is %lu times.", data, cnt, out); bt_assert_msg(out == cnt, "Index %lu shall be in trie %lu times, is %lu times.", data, cnt, out);
for (int i=0; i<64; i++)
bt_assert(path[i] == 0);
} }
/* /*