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Diffstat (limited to 'libdimension/dimension/base/array.h')
| -rw-r--r-- | libdimension/dimension/base/array.h | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/libdimension/dimension/base/array.h b/libdimension/dimension/base/array.h new file mode 100644 index 0000000..a54d0e5 --- /dev/null +++ b/libdimension/dimension/base/array.h @@ -0,0 +1,361 @@ +/************************************************************************* + * Copyright (C) 2009-2014 Tavian Barnes <tavianator@tavianator.com> * + * * + * This file is part of The Dimension Library. * + * * + * The Dimension Library is free software; you can redistribute it and/ * + * or modify it under the terms of the GNU Lesser General Public License * + * as published by the Free Software Foundation; either version 3 of the * + * License, or (at your option) any later version. * + * * + * The Dimension Library 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 * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with this program. If not, see * + * <http://www.gnu.org/licenses/>. * + *************************************************************************/ + +/** + * @file + * Simple dynamic arrays. + */ + +#ifndef DMNSN_BASE_H +#error "Please include <dimension/base.h> instead of this header directly." +#endif + +#include <stddef.h> /* For size_t */ +#include <stdlib.h> /* For qsort() */ +#include <string.h> /* For memcpy() */ + +/** Dynamic array type. */ +typedef struct dmnsn_array { + void *ptr; /**< @internal The actual memory. */ + size_t obj_size; /**< @internal The size of each object. */ + size_t length; /**< @internal The current size of the array. */ + size_t capacity; /**< @internal The size of the allocated space. */ +} dmnsn_array; + +/** + * @internal + * Initialize a new array. + * @param[out] array The array to initialize. + * @param[in] obj_size The size of the objects to store in the array. + */ +DMNSN_INLINE void +dmnsn_init_array(dmnsn_array *array, size_t obj_size) +{ + array->obj_size = obj_size; + array->length = 0; + array->capacity = 2; /* Start with capacity of 2 */ + + /* Allocate the memory */ + array->ptr = dmnsn_malloc(array->capacity*array->obj_size); +} + +/** + * Allocate an array. + * @param[in] obj_size The size of the objects to store in the array. + * @return An empty array. + */ +DMNSN_INLINE dmnsn_array * +dmnsn_new_array(size_t obj_size) +{ + dmnsn_array *array = DMNSN_MALLOC(dmnsn_array); + dmnsn_init_array(array, obj_size); + return array; +} + +/** + * Allocate an array. + * @param[in] type Type type of element to store in the array. + * @return An empty array. + */ +#define DMNSN_NEW_ARRAY(type) (dmnsn_new_array(sizeof(type))) + +/** + * Delete an array. + * @param[in,out] array The array to delete. + */ +DMNSN_INLINE void +dmnsn_delete_array(dmnsn_array *array) +{ + if (array) { + dmnsn_free(array->ptr); + dmnsn_free(array); + } +} + +/** + * @internal + * Free a pool-allocated array. + * @param[in,out] ptr The array to clean up. + */ +void dmnsn_array_cleanup(void *ptr); + +/** + * Allocate an array from a pool. + * @param[in] pool The memory pool to allocate from. + * @param[in] obj_size The size of the objects to store in the array. + * @return An empty array. + */ +DMNSN_INLINE dmnsn_array * +dmnsn_palloc_array(dmnsn_pool *pool, size_t obj_size) +{ + dmnsn_array *array = DMNSN_PALLOC_TIDY(pool, dmnsn_array, dmnsn_array_cleanup); + dmnsn_init_array(array, obj_size); + return array; +} + +/** + * Allocate an array from a pool. + * @param[in] pool The memory pool to allocate from. + * @param[in] type Type type of element to store in the array. + * @return An empty array. + */ +#define DMNSN_PALLOC_ARRAY(pool, type) (dmnsn_palloc_array(pool, sizeof(type))) + +/** + * Get the size of the array. + * @param[in] array The array in question. + * @return The number of elements in the array. + */ +DMNSN_INLINE size_t +dmnsn_array_size(const dmnsn_array *array) +{ + return array->length; +} + +/** + * Set the size of the array. + * @param[in,out] array The array to resize. + * @param[in] length The new length of the array. + */ +DMNSN_INLINE void +dmnsn_array_resize(dmnsn_array *array, size_t length) +{ + if (length > array->capacity) { + /* Resize if we don't have enough capacity */ + array->capacity = length*2; /* We are greedy */ + array->ptr = dmnsn_realloc(array->ptr, array->obj_size*array->capacity); + } + + array->length = length; +} + +/** + * Copy an array. + * @param[in] array The array to copy. + * @return A copy of the array. + */ +DMNSN_INLINE dmnsn_array * +dmnsn_array_copy(const dmnsn_array *array) +{ + dmnsn_array *copy = dmnsn_new_array(array->obj_size); + dmnsn_array_resize(copy, dmnsn_array_size(array)); + memcpy(copy->ptr, array->ptr, dmnsn_array_size(array)*array->obj_size); + return copy; +} + +/** + * Split an array in half. + * @param[in,out] array The array to split. + * @return The second half of the array. + */ +DMNSN_INLINE dmnsn_array * +dmnsn_array_split(dmnsn_array *array) +{ + dmnsn_array *half = dmnsn_new_array(array->obj_size); + size_t new_size = dmnsn_array_size(array)/2; + size_t old_size = dmnsn_array_size(array) - new_size; + dmnsn_array_resize(half, new_size); + memcpy(half->ptr, (char *)array->ptr + old_size*array->obj_size, + new_size*array->obj_size); + dmnsn_array_resize(array, old_size); + return half; +} + +/** + * Get the i'th element. + * @param[in] array The array to access. + * @param[in] i The index of the element to extract. + * @param[out] obj The location to store the extracted object. + */ +DMNSN_INLINE void +dmnsn_array_get(const dmnsn_array *array, size_t i, void *obj) +{ + dmnsn_assert(i < dmnsn_array_size(array), "Array index out of bounds."); + memcpy(obj, (char *)array->ptr + array->obj_size*i, array->obj_size); +} + +/** + * Set the i'th object, expanding the array if necessary. + * @param[in,out] array The array to modify. + * @param[in] i The index to update. + * @param[in] obj The location of the object to copy into the array. + */ +DMNSN_INLINE void +dmnsn_array_set(dmnsn_array *array, size_t i, const void *obj) +{ + if (i >= dmnsn_array_size(array)) { + /* Resize if i is out of range */ + dmnsn_array_resize(array, i + 1); + } + memcpy((char *)array->ptr + array->obj_size*i, obj, array->obj_size); +} + +/** + * First element. + * @param[in] array The array to index. + * @return The address of the first element of the array. + */ +DMNSN_INLINE void * +dmnsn_array_first(const dmnsn_array *array) +{ + return array->ptr; +} + +/** + * Last element. + * @param[in] array The array to index. + * @return The address of the last element of the array. + */ +DMNSN_INLINE void * +dmnsn_array_last(const dmnsn_array *array) +{ + return (char *)array->ptr + array->obj_size*(array->length - 1); +} + +/** + * Arbitrary element access. + * @param[in] array The array to index. + * @param[in] i The index to access. + * @return The address of the i'th element of the array. + */ +DMNSN_INLINE void * +dmnsn_array_at(const dmnsn_array *array, size_t i) +{ + dmnsn_assert(i < dmnsn_array_size(array), "Array index out of bounds."); + return (char *)array->ptr + array->obj_size*i; +} + +/** + * Push an object to the end of the array. + * @param[in,out] array The array to append to. + * @param[in] obj The location of the object to push. + */ +DMNSN_INLINE void +dmnsn_array_push(dmnsn_array *array, const void *obj) +{ + dmnsn_array_set(array, dmnsn_array_size(array), obj); +} + +/** + * Pop an object from the end of the array. + * @param[in,out] array The array to pop from. + * @param[out] obj The location to store the extracted object. + */ +DMNSN_INLINE void +dmnsn_array_pop(dmnsn_array *array, void *obj) +{ + size_t size = dmnsn_array_size(array); + dmnsn_assert(size > 0, "Array is empty."); + dmnsn_array_get(array, size - 1, obj); /* Copy the object */ + dmnsn_array_resize(array, size - 1); /* Shrink the array */ +} + +/** + * Insert an item into the middle of the array. This is O(n). + * @param[in,out] array The array to insert to. + * @param[in] i The index at which to insert. + * @param[in] obj The object to insert. + */ +DMNSN_INLINE void +dmnsn_array_insert(dmnsn_array *array, size_t i, const void *obj) +{ + size_t size = dmnsn_array_size(array) + 1; + if (i >= size) + size = i + 1; + dmnsn_array_resize(array, size); + + /* Move the elements at and after `i' 1 to the right */ + memmove((char *)array->ptr + array->obj_size*(i + 1), + (char *)array->ptr + array->obj_size*i, + array->obj_size*(size - i - 1)); + /* Insert `obj' at `i' */ + memcpy((char *)array->ptr + array->obj_size*i, obj, array->obj_size); +} + +/** + * Remove an item from the middle of the array. This is O(n). + * @param[in,out] array The array to remove from. + * @param[in] i The index to remove. + */ +DMNSN_INLINE void +dmnsn_array_remove(dmnsn_array *array, size_t i) +{ + size_t size = dmnsn_array_size(array); + dmnsn_assert(i < size, "Array index out of bounds."); + /* Move the array elements after `i' 1 to the left */ + memmove((char *)array->ptr + array->obj_size*i, + (char *)array->ptr + array->obj_size*(i + 1), + array->obj_size*(size - i - 1)); + /* Decrease the size by 1 */ + dmnsn_array_resize(array, size - 1); +} + +/** + * Apply a callback to each element of an array. + * @param[in,out] array The array. + * @param[in] callback The callback to apply to the elements. + */ +DMNSN_INLINE void +dmnsn_array_apply(dmnsn_array *array, dmnsn_callback_fn *callback) +{ + char *i, *last = (char *)dmnsn_array_last(array); + for (i = (char *)dmnsn_array_first(array); i <= last; i += array->obj_size) { + callback((void *)i); + } +} + +/** + * Callback type for array sorting. + * @param[in] a The first element. + * @param[in] b The second element. + * @return A negative value iff a < b, zero iff a == b, and a positive value iff + * a > b. + */ +typedef int dmnsn_array_comparator_fn(const void *a, const void *b); + +/** + * Sort an array. + * @param[in,out] array The array to sort. + * @param[in] comparator The sorting comparator to use. + */ +DMNSN_INLINE void +dmnsn_array_sort(dmnsn_array *array, dmnsn_array_comparator_fn *comparator) +{ + qsort(array->ptr, dmnsn_array_size(array), array->obj_size, comparator); +} + +/* Macros to shorten array iteration */ + +/** + * Iterate over an array. For example, + * @code + * DMNSN_ARRAY_FOREACH (int *, i, array) { + * printf("%d\n", *i); + * } + * @endcode + * + * @param type The (pointer) type to use as an iterator. + * @param i The name of the iterator within the loop body. + * @param[in] array The array to loop over. + */ +#define DMNSN_ARRAY_FOREACH(type, i, array) \ + for (type i = dmnsn_array_first(array); \ + (size_t)(i - (type)dmnsn_array_first(array)) < dmnsn_array_size(array); \ + ++i) |