+++ /dev/null
-/* Copyright (C) 2015-2017 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 <https://www.gnu.org/licenses/>.
- */
-
-/**
- *
- * @file array.h
- * @brief A set of simple macros to make working with dynamic arrays easier.
- *
- * @note The C has no generics, so it is implemented mostly using macros.
- * Be aware of that, as direct usage of the macros in the evaluating macros
- * may lead to different expectations:
- *
- * @code{.c}
- * MIN(array_push(arr, val), other)
- * @endcode
- *
- * May evaluate the code twice, leading to unexpected behaviour.
- * This is a price to pay for the absence of proper generics.
- *
- * # Example usage:
- *
- * @code{.c}
- * array_t(const char*) arr;
- * array_init(arr);
- *
- * // Reserve memory in advance
- * if (array_reserve(arr, 2) < 0) {
- * return ENOMEM;
- * }
- *
- * // Already reserved, cannot fail
- * array_push(arr, "princess");
- * array_push(arr, "leia");
- *
- * // Not reserved, may fail
- * if (array_push(arr, "han") < 0) {
- * return ENOMEM;
- * }
- *
- * // It does not hide what it really is
- * for (size_t i = 0; i < arr.len; ++i) {
- * printf("%s\n", arr.at[i]);
- * }
- *
- * // Random delete
- * array_del(arr, 0);
- * @endcode
- * \addtogroup generics
- * @{
- */
-
-#pragma once
-#include <stdlib.h>
-
-/** Simplified Qt containers growth strategy. */
-static inline size_t array_next_count(size_t want)
-{
- if (want < 2048) {
- return (want < 20) ? want + 4 : want * 2;
- } else {
- return want + 2048;
- }
-}
-
-/** @internal Incremental memory reservation */
-static inline int array_std_reserve(void *baton, char **mem, size_t elm_size, size_t want, size_t *have)
-{
- if (*have >= want) {
- return 0;
- }
- /* Simplified Qt containers growth strategy */
- size_t next_size = array_next_count(want);
- void *mem_new = realloc(*mem, next_size * elm_size);
- if (mem_new != NULL) {
- *mem = mem_new;
- *have = next_size;
- return 0;
- }
- return -1;
-}
-
-/** @internal Wrapper for stdlib free. */
-static inline void array_std_free(void *baton, void *p)
-{
- free(p);
-}
-
-/** Declare an array structure. */
-#define array_t(type) struct {type * at; size_t len; size_t cap; }
-
-/** Zero-initialize the array. */
-#define array_init(array) ((array).at = NULL, (array).len = (array).cap = 0)
-
-/** Free and zero-initialize the array (plain malloc/free). */
-#define array_clear(array) \
- array_clear_mm(array, array_std_free, NULL)
-
-/** Make the array empty and free pointed-to memory.
- * Mempool usage: pass mm_free and a knot_mm_t* . */
-#define array_clear_mm(array, free, baton) \
- (free)((baton), (array).at), array_init(array)
-
-/** Reserve capacity for at least n elements.
- * @return 0 if success, <0 on failure */
-#define array_reserve(array, n) \
- array_reserve_mm(array, n, array_std_reserve, NULL)
-
-/** Reserve capacity for at least n elements.
- * Mempool usage: pass kr_memreserve and a knot_mm_t* .
- * @return 0 if success, <0 on failure */
-#define array_reserve_mm(array, n, reserve, baton) \
- (reserve)((baton), (char **) &(array).at, sizeof((array).at[0]), (n), &(array).cap)
-
-/**
- * Push value at the end of the array, resize it if necessary.
- * Mempool usage: pass kr_memreserve and a knot_mm_t* .
- * @note May fail if the capacity is not reserved.
- * @return element index on success, <0 on failure
- */
-#define array_push_mm(array, val, reserve, baton) \
- (int)((array).len < (array).cap ? ((array).at[(array).len] = val, (array).len++) \
- : (array_reserve_mm(array, ((array).cap + 1), reserve, baton) < 0 ? -1 \
- : ((array).at[(array).len] = val, (array).len++)))
-
-/**
- * Push value at the end of the array, resize it if necessary (plain malloc/free).
- * @note May fail if the capacity is not reserved.
- * @return element index on success, <0 on failure
- */
-#define array_push(array, val) \
- array_push_mm(array, val, array_std_reserve, NULL)
-
-/**
- * Pop value from the end of the array.
- */
-#define array_pop(array) \
- (array).len -= 1
-
-/**
- * Remove value at given index.
- * @return 0 on success, <0 on failure
- */
-#define array_del(array, i) \
- (int)((i) < (array).len ? ((array).len -= 1,(array).at[i] = (array).at[(array).len], 0) : -1)
-
-/**
- * Return last element of the array.
- * @warning Undefined if the array is empty.
- */
-#define array_tail(array) \
- (array).at[(array).len - 1]
-
-/** @} */
projects / thirdparty / knot-resolver.git / commitdiff
