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Diffstat (limited to 'src/libknot/rdataset.h')
| -rw-r--r-- | src/libknot/rdataset.h | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/src/libknot/rdataset.h b/src/libknot/rdataset.h new file mode 100644 index 0000000..6d98086 --- /dev/null +++ b/src/libknot/rdataset.h @@ -0,0 +1,218 @@ +/* Copyright (C) 2022 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 <https://www.gnu.org/licenses/>. + */ + +/*! + * \file + * + * \brief API for manipulating RR arrays. + * + * \addtogroup rr + * @{ + */ + +#pragma once + +#include <assert.h> +#include <stddef.h> +#include <stdint.h> +#include <stdbool.h> + +#include "libknot/errcode.h" +#include "libknot/mm_ctx.h" +#include "libknot/rdata.h" + +/*!< \brief Set of RRs. */ +typedef struct { + uint16_t count; /*!< \brief Count of RRs stored in the structure. */ + uint32_t size; /*!< \brief Size of the rdata array. */ + knot_rdata_t *rdata; /*!< \brief Serialized rdata, canonically sorted. */ +} knot_rdataset_t; + +/*! + * \brief Initializes RRS structure. + * + * \param rrs Structure to be initialized. + */ +inline static void knot_rdataset_init(knot_rdataset_t *rrs) +{ + if (rrs != NULL) { + rrs->count = 0; + rrs->size = 0; + rrs->rdata = NULL; + } +} + +/*! + * \brief Advance to the next rdata in a rdataset. + * + * Useful for iteration. + * + * \note Ensure that this operation makes sense! + * + * \param rr Current RR. + * + * \return Next RR. + */ +static inline knot_rdata_t *knot_rdataset_next(knot_rdata_t *rr) +{ + assert(rr); + return (knot_rdata_t *)((uint8_t *)rr + knot_rdata_size(rr->len)); +} + +/*! + * \brief Frees data initialized by RRS structure, but not the structure itself. + * + * \param rrs Structure to be cleared. + * \param mm Memory context used to create allocations. + */ +void knot_rdataset_clear(knot_rdataset_t *rrs, knot_mm_t *mm); + +/*! + * \brief Deep copies RRS structure. All data are duplicated. + * + * \param dst Copy destination. + * \param src Copy source. + * \param mm Memory context. + * + * \return KNOT_E* + */ +int knot_rdataset_copy(knot_rdataset_t *dst, const knot_rdataset_t *src, knot_mm_t *mm); + +/*! + * \brief Gets RR from RRS structure, using given position. + * + * \param rrs RRS structure to get RR from. + * \param pos Position to use (counted from 0). + * + * \return Pointer to RR at \a pos position. + */ +knot_rdata_t *knot_rdataset_at(const knot_rdataset_t *rrs, uint16_t pos); + +/*! + * \brief Adds single RR into RRS structure. All data are copied. + * + * \param rrs RRS structure to add RR into. + * \param rr RR to add. + * \param mm Memory context. + * + * \return KNOT_E* + */ +int knot_rdataset_add(knot_rdataset_t *rrs, const knot_rdata_t *rr, knot_mm_t *mm); + +/*! + * \brief RRS equality check. + * + * \param rrs1 First RRS to be compared. + * \param rrs2 Second RRS to be compared. + * + * \retval true if rrs1 == rrs2. + * \retval false if rrs1 != rrs2. + */ +bool knot_rdataset_eq(const knot_rdataset_t *rrs1, const knot_rdataset_t *rrs2); + +/*! + * \brief Returns true if \a rr is present in \a rrs, false otherwise. + * + * \param rrs RRS to search in. + * \param rr RR to compare with. + * + * \retval true if \a rr is present in \a rrs. + * \retval false if \a rr is not present in \a rrs. + */ +bool knot_rdataset_member(const knot_rdataset_t *rrs, const knot_rdata_t *rr); + +/*! + * \brief Returns true if \a subset is a sub-set of \a of, false otherwise. + * + * \param subset RRS to check. + * \param of RRS to search in. + * + * \retval true if \a subset is a sub-set of \a of. + * \retval false if \a subset is not a sub-set of \a of. + */ +bool knot_rdataset_subset(const knot_rdataset_t *subset, const knot_rdataset_t *of); + +/*! + * \brief Merges two RRS into the first one. Second RRS is left intact. + * Canonical order is preserved. + * + * \param rrs1 Destination RRS (merge here). + * \param rrs2 RRS to be merged (merge from). + * \param mm Memory context. + * + * \return KNOT_E* + */ +int knot_rdataset_merge(knot_rdataset_t *rrs1, const knot_rdataset_t *rrs2, + knot_mm_t *mm); + +/*! + * \brief RRS set-like intersection. Full compare is done. + * + * \param rrs1 First RRS to intersect. + * \param rrs2 Second RRS to intersect. + * \param out Output RRS with intersection, RDATA are created anew. + * \param mm Memory context. Will be used to create new RDATA. + * + * \return KNOT_E* + */ +int knot_rdataset_intersect(const knot_rdataset_t *rrs1, const knot_rdataset_t *rrs2, + knot_rdataset_t *out, knot_mm_t *mm); + +/*! + * \brief Does set-like RRS intersection. \a from RRS is changed. + * + * \param from RRS to be modified by intersection. + * \param what RRS to intersect. + * \param mm Memory context use to reallocated \a from data. + * + * \return KNOT_E* + */ +int knot_rdataset_intersect2(knot_rdataset_t *from, const knot_rdataset_t *what, + knot_mm_t *mm); + +/*! + * \brief Does set-like RRS subtraction. \a from RRS is changed. + * + * \param from RRS to subtract from. + * \param what RRS to subtract. + * \param mm Memory context use to reallocated \a from data. + * + * \return KNOT_E* + */ +int knot_rdataset_subtract(knot_rdataset_t *from, const knot_rdataset_t *what, + knot_mm_t *mm); + +/*! + * \brief Removes single RR from RRS structure. + * + * \param rrs RRS structure to remove RR from. + * \param rr RR to remove. + * \param mm Memory context. + * + * \return KNOT_E* + */ +inline static int knot_rdataset_remove(knot_rdataset_t *rrs, const knot_rdata_t *rr, + knot_mm_t *mm) +{ + if (rr == NULL) { + return KNOT_EINVAL; + } + + knot_rdataset_t rrs_rm = { 1, knot_rdata_size(rr->len), (knot_rdata_t *)rr }; + return knot_rdataset_subtract(rrs, &rrs_rm, mm); +} + +/*! @} */ |