ucx: src/cx/linked_list.h@741a2040fa33 (annotated)

src/cx/linked_list.h@741a2040fa33 (annotated)

src/cx/linked_list.h

Mon, 18 Dec 2023 16:14:07 +0100

author: Mike Becker <universe@uap-core.de>
date: Mon, 18 Dec 2023 16:14:07 +0100
changeset 763: 741a2040fa33
parent 759: 475335643af4
child 764: ccbdbd088455
permissions: -rw-r--r--

make cx_cmp_ptr default comparator for pointer lists - relates to #340

 /*
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
  *
  * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *   1. Redistributions of source code must retain the above copyright
  *      notice, this list of conditions and the following disclaimer.
  *
  *   2. Redistributions in binary form must reproduce the above copyright
  *      notice, this list of conditions and the following disclaimer in the
  *      documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */
 /**
  * \file linked_list.h
  * \brief Linked list implementation.
  * \details Also provides several low-level functions for custom linked list implementations.
  * \author Mike Becker
  * \author Olaf Wintermann
  * \copyright 2-Clause BSD License
  */
 #ifndef UCX_LINKED_LIST_H
 #define UCX_LINKED_LIST_H
 #include "common.h"
 #include "list.h"
 #ifdef __cplusplus
 extern "C" {
 #endif
 /**
  * Set this flag to true, if you want to disable the use of SBO for
  * linked list swap operations.
  */
 extern bool CX_DISABLE_LINKED_LIST_SWAP_SBO;
 /**
  * Allocates a linked list for storing elements with \p item_size bytes each.
  *
  * If \p item_size is CX_STORE_POINTERS, the created list will be created as if
  * cxListStorePointers() was called immediately after creation and the compare
  * function will be automatically set to cx_cmp_ptr(), if none is given.
  *
  * @param allocator the allocator for allocating the list nodes
  * (if \c NULL the cxDefaultAllocator will be used)
  * @param comparator the comparator for the elements
  * (if \c NULL, and the list is not storing pointers, sort and find
  * functions will not work)
  * @param item_size the size of each element in bytes
  * @return the created list
  */
 CxList *cxLinkedListCreate(
         CxAllocator const *allocator,
         cx_compare_func comparator,
         size_t item_size
 );
 /**
  * Allocates a linked list for storing elements with \p item_size bytes each.
  *
  * The list will use cxDefaultAllocator and no comparator function. If you want
  * to call functions that need a comparator, you must either set one immediately
  * after list creation or use cxLinkedListCreate().
  *
  * If \p item_size is CX_STORE_POINTERS, the created list will be created as if
  * cxListStorePointers() was called immediately after creation and the compare
  * function will be automatically set to cx_cmp_ptr().
  *
  * @param item_size the size of each element in bytes
  * @return the created list
  */
 #define cxLinkedListCreateSimple(item_size) \
     cxLinkedListCreate(NULL, NULL, item_size)
 /**
  * Finds the node at a certain index.
  *
  * This function can be used to start at an arbitrary position within the list.
  * If the search index is large than the start index, \p loc_advance must denote
  * the location of some sort of \c next pointer (i.e. a pointer to the next node).
  * But it is also possible that the search index is smaller than the start index
  * (e.g. in cases where traversing a list backwards is faster) in which case
  * \p loc_advance must denote the location of some sort of \c prev pointer
  * (i.e. a pointer to the previous node).
  *
  * @param start a pointer to the start node
  * @param start_index the start index
  * @param loc_advance the location of the pointer to advance
  * @param index the search index
  * @return the node found at the specified index
  */
 void *cx_linked_list_at(
         void const *start,
         size_t start_index,
         ptrdiff_t loc_advance,
         size_t index
 ) __attribute__((__nonnull__));
 /**
  * Finds the index of an element within a linked list.
  *
  * @param start a pointer to the start node
  * @param loc_advance the location of the pointer to advance
  * @param loc_data the location of the \c data pointer within your node struct
  * @param cmp_func a compare function to compare \p elem against the node data
  * @param elem a pointer to the element to find
  * @return the index of the element or a negative value if it could not be found
  */
 ssize_t cx_linked_list_find(
         void const *start,
         ptrdiff_t loc_advance,
         ptrdiff_t loc_data,
         cx_compare_func cmp_func,
         void const *elem
 ) __attribute__((__nonnull__));
 /**
  * Finds the first node in a linked list.
  *
  * The function starts with the pointer denoted by \p node and traverses the list
  * along a prev pointer whose location within the node struct is
  * denoted by \p loc_prev.
  *
  * @param node a pointer to a node in the list
  * @param loc_prev the location of the \c prev pointer
  * @return a pointer to the first node
  */
 void *cx_linked_list_first(
         void const *node,
         ptrdiff_t loc_prev
 ) __attribute__((__nonnull__));
 /**
  * Finds the last node in a linked list.
  *
  * The function starts with the pointer denoted by \p node and traverses the list
  * along a next pointer whose location within the node struct is
  * denoted by \p loc_next.
  *
  * @param node a pointer to a node in the list
  * @param loc_next the location of the \c next pointer
  * @return a pointer to the last node
  */
 void *cx_linked_list_last(
         void const *node,
         ptrdiff_t loc_next
 ) __attribute__((__nonnull__));
 /**
  * Finds the predecessor of a node in case it is not linked.
  *
  * \remark If \p node is not contained in the list starting with \p begin, the behavior is undefined.
  *
  * @param begin the node where to start the search
  * @param loc_next the location of the \c next pointer
  * @param node the successor of the node to find
  * @return the node or \c NULL if \p node has no predecessor
  */
 void *cx_linked_list_prev(
         void const *begin,
         ptrdiff_t loc_next,
         void const *node
 ) __attribute__((__nonnull__));
 /**
  * Adds a new node to a linked list.
  * The node must not be part of any list already.
  *
  * \remark One of the pointers \p begin or \p end may be \c NULL, but not both.
  *
  * @param begin a pointer to the begin node pointer (if your list has one)
  * @param end a pointer to the end node pointer (if your list has one)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  * @param new_node a pointer to the node that shall be appended
  */
 void cx_linked_list_add(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next,
         void *new_node
 ) __attribute__((__nonnull__(5)));
 /**
  * Prepends a new node to a linked list.
  * The node must not be part of any list already.
  *
  * \remark One of the pointers \p begin or \p end may be \c NULL, but not both.
  *
  * @param begin a pointer to the begin node pointer (if your list has one)
  * @param end a pointer to the end node pointer (if your list has one)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  * @param new_node a pointer to the node that shall be prepended
  */
 void cx_linked_list_prepend(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next,
         void *new_node
 ) __attribute__((__nonnull__(5)));
 /**
  * Links two nodes.
  *
  * @param left the new predecessor of \p right
  * @param right the new successor of \p left
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  */
 void cx_linked_list_link(
         void *left,
         void *right,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next
 ) __attribute__((__nonnull__));
 /**
  * Unlinks two nodes.
  *
  * If right is not the successor of left, the behavior is undefined.
  *
  * @param left the predecessor of \p right
  * @param right the successor of \p left
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  */
 void cx_linked_list_unlink(
         void *left,
         void *right,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next
 ) __attribute__((__nonnull__));
 /**
  * Inserts a new node after a given node of a linked list.
  * The new node must not be part of any list already.
  *
  * \note If you specify \c NULL as the \p node to insert after, this function needs either the \p begin or
  * the \p end pointer to determine the start of the list. Then the new node will be prepended to the list.
  *
  * @param begin a pointer to the begin node pointer (if your list has one)
  * @param end a pointer to the end node pointer (if your list has one)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  * @param node the node after which to insert (\c NULL if you want to prepend the node to the list)
  * @param new_node a pointer to the node that shall be prepended
  */
 void cx_linked_list_insert(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next,
         void *node,
         void *new_node
 ) __attribute__((__nonnull__(6)));
 /**
  * Inserts a chain of nodes after a given node of a linked list.
  * The chain must not be part of any list already.
  *
  * If you do not explicitly specify the end of the chain, it will be determined by traversing
  * the \c next pointer.
  *
  * \note If you specify \c NULL as the \p node to insert after, this function needs either the \p begin or
  * the \p end pointer to determine the start of the list. If only the \p end pointer is specified, you also need
  * to provide a valid \p loc_prev location.
  * Then the chain will be prepended to the list.
  *
  * @param begin a pointer to the begin node pointer (if your list has one)
  * @param end a pointer to the end node pointer (if your list has one)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  * @param node the node after which to insert (\c NULL to prepend the chain to the list)
  * @param insert_begin a pointer to the first node of the chain that shall be inserted
  * @param insert_end a pointer to the last node of the chain (or NULL if the last node shall be determined)
  */
 void cx_linked_list_insert_chain(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next,
         void *node,
         void *insert_begin,
         void *insert_end
 ) __attribute__((__nonnull__(6)));
 /**
  * Removes a node from the linked list.
  *
  * If the node to remove is the begin (resp. end) node of the list and if \p begin (resp. \p end)
  * addresses are provided, the pointers are adjusted accordingly.
  *
  * The following combinations of arguments are valid (more arguments are optional):
  * \li \p loc_next and \p loc_prev (ancestor node is determined by using the prev pointer, overall O(1) performance)
  * \li \p loc_next and \p begin (ancestor node is determined by list traversal, overall O(n) performance)
  *
  * \remark The \c next and \c prev pointers of the removed node are not cleared by this function and may still be used
  * to traverse to a former adjacent node in the list.
  *
  * @param begin a pointer to the begin node pointer (optional)
  * @param end a pointer to the end node pointer (optional)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  * @param node the node to remove
  */
 void cx_linked_list_remove(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next,
         void *node
 ) __attribute__((__nonnull__(5)));
 /**
  * Determines the size of a linked list starting with \p node.
  * @param node the first node
  * @param loc_next the location of the \c next pointer within the node struct
  * @return the size of the list or zero if \p node is \c NULL
  */
 size_t cx_linked_list_size(
         void const *node,
         ptrdiff_t loc_next
 );
 /**
  * Sorts a linked list based on a comparison function.
  *
  * This function can work with linked lists of the following structure:
  * \code
  * typedef struct node node;
  * struct node {
  *   node* prev;
  *   node* next;
  *   my_payload data;
  * }
  * \endcode
  *
  * @note This is a recursive function with at most logarithmic recursion depth.
  *
  * @param begin a pointer to the begin node pointer (required)
  * @param end a pointer to the end node pointer (optional)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if not present)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  * @param loc_data the location of the \c data pointer within your node struct
  * @param cmp_func the compare function defining the sort order
  */
 void cx_linked_list_sort(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next,
         ptrdiff_t loc_data,
         cx_compare_func cmp_func
 ) __attribute__((__nonnull__(1, 6)));
 /**
  * Compares two lists element wise.
  *
  * \note Both list must have the same structure.
  *
  * @param begin_left the begin of the left list (\c NULL denotes an empty list)
  * @param begin_right the begin of the right list  (\c NULL denotes an empty list)
  * @param loc_advance the location of the pointer to advance
  * @param loc_data the location of the \c data pointer within your node struct
  * @param cmp_func the function to compare the elements
  * @return the first non-zero result of invoking \p cmp_func or: negative if the left list is smaller than the
  * right list, positive if the left list is larger than the right list, zero if both lists are equal.
  */
 int cx_linked_list_compare(
         void const *begin_left,
         void const *begin_right,
         ptrdiff_t loc_advance,
         ptrdiff_t loc_data,
         cx_compare_func cmp_func
 ) __attribute__((__nonnull__(5)));
 /**
  * Reverses the order of the nodes in a linked list.
  *
  * @param begin a pointer to the begin node pointer (required)
  * @param end a pointer to the end node pointer (optional)
  * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
  * @param loc_next the location of a \c next pointer within your node struct (required)
  */
 void cx_linked_list_reverse(
         void **begin,
         void **end,
         ptrdiff_t loc_prev,
         ptrdiff_t loc_next
 ) __attribute__((__nonnull__(1)));
 #ifdef __cplusplus
 } // extern "C"
 #endif
 #endif // UCX_LINKED_LIST_H

Mercurial > hg > ucx / annotate

src/cx/linked_list.h@741a2040fa33 (annotated)

src/cx/linked_list.h