--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ucx/cx/linked_list.h Sun Nov 06 15:53:32 2022 +0100
@@ -0,0 +1,450 @@
+/*
+ * 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
+ * \version 3.0
+ * \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
+
+/**
+ * Allocates a linked list for storing elements with \p item_size bytes each.
+ *
+ * @remark Elements added to the list are copied, therefore a possible destructor
+ * MUST NOT free the memory pointed to by its argument.
+ *
+ * @param allocator the allocator for allocating the list nodes
+ * @param comparator the comparator for the elements
+ * @param item_size the size of each element in bytes
+ * @return the created list
+ */
+CxList *cxLinkedListCreate(
+ CxAllocator const *allocator,
+ CxListComparator comparator,
+ size_t item_size
+) __attribute__((__nonnull__));
+
+/**
+ * Allocates a linked list for storing pointers.
+ *
+ * If you want to store the elements directly in this list, use cxLinkedListCreate().
+ *
+ * @remark Since only pointers are stored in this list, a possible destructor
+ * MAY free the memory pointed to by its argument in order to prevent memory leaks.
+ *
+ * @param allocator the allocator for allocating the list nodes
+ * @param comparator the comparator for the elements
+ * @return the created list
+ */
+CxList *cxPointerLinkedListCreate(
+ CxAllocator const *allocator,
+ CxListComparator comparator
+) __attribute__((__nonnull__));
+
+/**
+ * Creates a linked list using the data from an array.
+ *
+ * @remark Elements added to the list are copied, therefore a possible destructor
+ * MUST NOT free the memory pointed to by its argument.
+ *
+ * @param allocator the allocator for allocating the list nodes
+ * @param comparator the comparator for the elements
+ * @param item_size the size of one item in the array
+ * @param num_items the number of items
+ * @param array the array data
+ * @return the created list
+ */
+CxList *cxLinkedListFromArray(
+ CxAllocator const *allocator,
+ CxListComparator comparator,
+ size_t item_size,
+ size_t num_items,
+ void const *array
+) __attribute__((__nonnull__));
+
+/**
+ * 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 follow_ptr \c false if the pointer denoted by \p loc_data shall be passed to the \p cmp_func.
+ * If \c true, the data at \p loc_data is assumed to be a pointer, dereferenced, and then passed to \p cmp_func.
+ * @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 past-one index if the element could not be found
+ */
+size_t cx_linked_list_find(
+ void const *start,
+ ptrdiff_t loc_advance,
+ ptrdiff_t loc_data,
+ bool follow_ptr,
+ CxListComparator 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 structures:
+ * \code
+ * typedef struct node node;
+ * struct node {
+ * node* prev;
+ * node* next;
+ * my_payload data; // in this case set follow_ptr = 0
+ * }
+ *
+ * typedef struct ptr_node ptr_node;
+ * struct ptr_node {
+ * ptr_node* prev;
+ * ptr_node* next;
+ * my_payload* data; // in this case set follow_ptr = 1
+ * }
+ * \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 follow_ptr \c false if the pointer denoted by \p loc_data shall be passed to the \p cmp_func.
+ * If \c true, the data at \p loc_data is assumed to be a pointer, dereferenced, and then passed to \p cmp_func.
+ * @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,
+ bool follow_ptr,
+ CxListComparator cmp_func
+) __attribute__((__nonnull__(1, 7)));
+
+
+/**
+ * Compares two lists element wise.
+ *
+ * The \c follow_ptr flags have the following meaning: if \c false, the pointer denoted by \p loc_data shall
+ * directly be passed to the \p cmp_func.
+ * If \c true, the data at \p loc_data is assumed to be a pointer, dereferenced, and then passed to \p cmp_func.
+ *
+ * \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 follow_ptr_left indicates whether pointers in the left list shall be dereferenced
+ * @param follow_ptr_right indicates whether pointers in the right list shall be dereferenced
+ * @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,
+ bool follow_ptr_left,
+ bool follow_ptr_right,
+ CxListComparator cmp_func
+) __attribute__((__nonnull__(7)));
+
+/**
+ * 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 */