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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 00:53:35 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 00:53:35 +0000 |
commit | 69c6a41ffb878ef98c9378ed4b1634a404cfaa7f (patch) | |
tree | b2a4f704565d62fbb129ab9dc3b35977c50e6e7f /src/contrib/qp-trie/trie.h | |
parent | Initial commit. (diff) | |
download | knot-upstream.tar.xz knot-upstream.zip |
Adding upstream version 2.7.6.upstream/2.7.6upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/contrib/qp-trie/trie.h')
-rw-r--r-- | src/contrib/qp-trie/trie.h | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/src/contrib/qp-trie/trie.h b/src/contrib/qp-trie/trie.h new file mode 100644 index 0000000..28ea571 --- /dev/null +++ b/src/contrib/qp-trie/trie.h @@ -0,0 +1,112 @@ +/* Copyright (C) 2017 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#pragma once + +#include <stdbool.h> +#include <stdint.h> + +#include "libknot/mm_ctx.h" + +/*! + * \brief Native API of QP-tries: + * + * - keys are char strings, not necessarily zero-terminated, + * the structure copies the contents of the passed keys + * - values are void* pointers, typically you get an ephemeral pointer to it + * - key lengths are limited by 2^32-1 ATM + */ + +/*! \brief Element value. */ +typedef void* trie_val_t; + +/*! \brief Opaque structure holding a QP-trie. */ +typedef struct trie trie_t; + +/*! \brief Opaque type for holding a QP-trie iterator. */ +typedef struct trie_it trie_it_t; + +/*! \brief Create a trie instance. */ +trie_t* trie_create(knot_mm_t *mm); + +/*! \brief Free a trie instance. */ +void trie_free(trie_t *tbl); + +/*! \brief Clear a trie instance (make it empty). */ +void trie_clear(trie_t *tbl); + +/*! \brief Return the number of keys in the trie. */ +size_t trie_weight(const trie_t *tbl); + +/*! \brief Search the trie, returning NULL on failure. */ +trie_val_t* trie_get_try(trie_t *tbl, const char *key, uint32_t len); + +/*! \brief Search the trie, inserting NULL trie_val_t on failure. */ +trie_val_t* trie_get_ins(trie_t *tbl, const char *key, uint32_t len); + +/*! + * \brief Search for less-or-equal element. + * + * \param tbl Trie. + * \param key Searched key. + * \param len Key length. + * \param val Must be valid; it will be set to NULL if not found or errored. + * \return KNOT_EOK for exact match, 1 for previous, KNOT_ENOENT for not-found, + * or KNOT_E*. + */ +int trie_get_leq(trie_t *tbl, const char *key, uint32_t len, trie_val_t **val); + +/*! + * \brief Apply a function to every trie_val_t, in order. + * + * \return KNOT_EOK if success or KNOT_E* if error. + */ +int trie_apply(trie_t *tbl, int (*f)(trie_val_t *, void *), void *d); + +/*! + * \brief Remove an item, returning KNOT_EOK if succeeded or KNOT_ENOENT if not found. + * + * If val!=NULL and deletion succeeded, the deleted value is set. + */ +int trie_del(trie_t *tbl, const char *key, uint32_t len, trie_val_t *val); + +/*! \brief Create a new iterator pointing to the first element (if any). */ +trie_it_t* trie_it_begin(trie_t *tbl); + +/*! + * \brief Advance the iterator to the next element. + * + * Iteration is in ascending lexicographical order. + * In particular, the empty string would be considered as the very first. + */ +void trie_it_next(trie_it_t *it); + +/*! \brief Test if the iterator has gone past the last element. */ +bool trie_it_finished(trie_it_t *it); + +/*! \brief Free any resources of the iterator. It's OK to call it on NULL. */ +void trie_it_free(trie_it_t *it); + +/*! + * \brief Return pointer to the key of the current element. + * + * \note The len is uint32_t internally but size_t is better for our usage + * as it is without an additional type conversion. + */ +const char* trie_it_key(trie_it_t *it, size_t *len); + +/*! \brief Return pointer to the value of the current element (writable). */ +trie_val_t* trie_it_val(trie_it_t *it); |