src/cx/list.h

Wed, 08 Feb 2023 20:26:09 +0100

author
Mike Becker <universe@uap-core.de>
date
Wed, 08 Feb 2023 20:26:09 +0100
changeset 647
2e6e9d9f2159
parent 641
d402fead3386
child 655
7340c4255f1f
permissions
-rw-r--r--

implement swap function for list elements - fixes #218

     1 /*
     2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
     3  *
     4  * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
     5  *
     6  * Redistribution and use in source and binary forms, with or without
     7  * modification, are permitted provided that the following conditions are met:
     8  *
     9  *   1. Redistributions of source code must retain the above copyright
    10  *      notice, this list of conditions and the following disclaimer.
    11  *
    12  *   2. Redistributions in binary form must reproduce the above copyright
    13  *      notice, this list of conditions and the following disclaimer in the
    14  *      documentation and/or other materials provided with the distribution.
    15  *
    16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
    20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    26  * POSSIBILITY OF SUCH DAMAGE.
    27  */
    28 /**
    29  * \file list.h
    30  * \brief Interface for list implementations.
    31  * \author Mike Becker
    32  * \author Olaf Wintermann
    33  * \version 3.0
    34  * \copyright 2-Clause BSD License
    35  */
    37 #ifndef UCX_LIST_H
    38 #define UCX_LIST_H
    40 #include "common.h"
    41 #include "allocator.h"
    42 #include "iterator.h"
    44 #ifdef __cplusplus
    45 extern "C" {
    46 #endif
    48 /**
    49  * A comparator function comparing two list elements.
    50  */
    51 typedef int(*CxListComparator)(
    52         void const *left,
    53         void const *right
    54 );
    56 /**
    57  * List class type.
    58  */
    59 typedef struct cx_list_class_s cx_list_class;
    61 /**
    62  * Structure for holding the base data of a list.
    63  */
    64 struct cx_list_s {
    65     /**
    66      * The list class definition.
    67      */
    68     cx_list_class const *cl;
    69     /**
    70      * The actual implementation in case the list class is delegating.
    71      */
    72     cx_list_class const *climpl;
    73     /**
    74      * The allocator to use.
    75      */
    76     CxAllocator const *allocator;
    77     /**
    78      * The comparator function for the elements.
    79      */
    80     CxListComparator cmpfunc;
    81     /**
    82      * The size of each element (payload only).
    83      */
    84     size_t itemsize;
    85     /**
    86      * The size of the list (number of currently stored elements).
    87      */
    88     size_t size;
    89     /**
    90      * The capacity of the list (maximum number of elements).
    91      */
    92     size_t capacity;
    93     union {
    94         /**
    95          * An optional simple destructor for the list contents that admits the free() interface.
    96          *
    97          * @remark Set content_destructor_type to #CX_DESTRUCTOR_SIMPLE.
    98          *
    99          * @attention Read the documentation of the particular list implementation
   100          * whether this destructor shall only destroy the contents or also free the memory.
   101          */
   102         cx_destructor_func simple_destructor;
   103         /**
   104          * An optional advanced destructor for the list contents providing additional data.
   105          *
   106          * @remark Set content_destructor_type to #CX_DESTRUCTOR_ADVANCED.
   107          *
   108          * @attention Read the documentation of the particular list implementation
   109          * whether this destructor shall only destroy the contents or also free the memory.
   110          */
   111         cx_advanced_destructor advanced_destructor;
   112     };
   113     /**
   114      * The type of destructor to use.
   115      */
   116     enum cx_destructor_type content_destructor_type;
   117 };
   119 /**
   120  * The class definition for arbitrary lists.
   121  */
   122 struct cx_list_class_s {
   123     /**
   124      * Destructor function.
   125      */
   126     void (*destructor)(struct cx_list_s *list);
   128     /**
   129      * Member function for inserting a single elements.
   130      * Implementors SHOULD see to performant implementations for corner cases.
   131      */
   132     int (*insert_element)(
   133             struct cx_list_s *list,
   134             size_t index,
   135             void const *data
   136     );
   138     /**
   139      * Member function for inserting multiple elements.
   140      * Implementors SHOULD see to performant implementations for corner cases.
   141      */
   142     size_t (*insert_array)(
   143             struct cx_list_s *list,
   144             size_t index,
   145             void const *data,
   146             size_t n
   147     );
   149     /**
   150      * Member function for inserting an element relative to an iterator position.
   151      */
   152     int (*insert_iter)(
   153             struct cx_mut_iterator_s *iter,
   154             void const *elem,
   155             int prepend
   156     );
   158     /**
   159      * Member function for removing an element.
   160      */
   161     int (*remove)(
   162             struct cx_list_s *list,
   163             size_t index
   164     );
   166     /**
   167      * Member function for swapping two elements.
   168      */
   169     int (*swap)(
   170             struct cx_list_s *list,
   171             size_t i,
   172             size_t j
   173     );
   175     /**
   176      * Member function for element lookup.
   177      */
   178     void *(*at)(
   179             struct cx_list_s const *list,
   180             size_t index
   181     );
   183     /**
   184      * Member function for finding an element.
   185      */
   186     size_t (*find)(
   187             struct cx_list_s const *list,
   188             void const *elem
   189     );
   191     /**
   192      * Member function for sorting the list in place.
   193      */
   194     void (*sort)(struct cx_list_s *list);
   196     /**
   197      * Member function for comparing this list to another list of the same type.
   198      */
   199     int (*compare)(
   200             struct cx_list_s const *list,
   201             struct cx_list_s const *other
   202     );
   204     /**
   205      * Member function for reversing the order of the items.
   206      */
   207     void (*reverse)(struct cx_list_s *list);
   209     /**
   210      * Member function for returning an iterator pointing to the specified index.
   211      */
   212     struct cx_iterator_s (*iterator)(
   213             struct cx_list_s const *list,
   214             size_t index
   215     );
   216 };
   218 /**
   219  * Common type for all list implementations.
   220  */
   221 typedef struct cx_list_s CxList;
   223 /**
   224  * Advises the list to store copies of the objects (default mode of operation).
   225  *
   226  * Retrieving objects from this list will yield pointers to the copies stored
   227  * within this list.
   228  *
   229  * @param list the list
   230  * @see cxListStorePointers()
   231  */
   232 __attribute__((__nonnull__))
   233 void cxListStoreObjects(CxList *list);
   235 /**
   236  * Advises the list to only store pointers to the objects.
   237  *
   238  * Retrieving objects from this list will yield the original pointers stored.
   239  *
   240  * @note This function forcibly sets the element size to the size of a pointer.
   241  * Invoking this function on a non-empty list that already stores copies of
   242  * objects is undefined.
   243  *
   244  * @param list the list
   245  * @see cxListStoreObjects()
   246  */
   247 __attribute__((__nonnull__))
   248 void cxListStorePointers(CxList *list);
   250 /**
   251  * Returns true, if this list is storing pointers instead of the actual data.
   252  *
   253  * @param list
   254  * @return
   255  * @see cxListStorePointers()
   256  */
   257 __attribute__((__nonnull__))
   258 bool cxListIsStoringPointers(CxList *list);
   260 /**
   261  * Adds an item to the end of the list.
   262  *
   263  * @param list the list
   264  * @param elem a pointer to the element to add
   265  * @return zero on success, non-zero on memory allocation failure
   266  * @see cxListAddArray()
   267  */
   268 __attribute__((__nonnull__))
   269 static inline int cxListAdd(
   270         CxList *list,
   271         void const *elem
   272 ) {
   273     return list->cl->insert_element(list, list->size, elem);
   274 }
   276 /**
   277  * Adds multiple items to the end of the list.
   278  *
   279  * This method is more efficient than invoking cxListAdd() multiple times.
   280  *
   281  * If there is not enough memory to add all elements, the returned value is
   282  * less than \p n.
   283  *
   284  * If this list is storing pointers instead of objects \p array is expected to
   285  * be an array of pointers.
   286  *
   287  * @param list the list
   288  * @param array a pointer to the elements to add
   289  * @param n the number of elements to add
   290  * @return the number of added elements
   291  */
   292 __attribute__((__nonnull__))
   293 static inline size_t cxListAddArray(
   294         CxList *list,
   295         void const *array,
   296         size_t n
   297 ) {
   298     return list->cl->insert_array(list, list->size, array, n);
   299 }
   301 /**
   302  * Inserts an item at the specified index.
   303  *
   304  * If \p index equals the list \c size, this is effectively cxListAdd().
   305  *
   306  * @param list the list
   307  * @param index the index the element shall have
   308  * @param elem a pointer to the element to add
   309  * @return zero on success, non-zero on memory allocation failure
   310  * or when the index is out of bounds
   311  * @see cxListInsertAfter()
   312  * @see cxListInsertBefore()
   313  */
   314 __attribute__((__nonnull__))
   315 static inline int cxListInsert(
   316         CxList *list,
   317         size_t index,
   318         void const *elem
   319 ) {
   320     return list->cl->insert_element(list, index, elem);
   321 }
   323 /**
   324  * Inserts multiple items to the list at the specified index.
   325  * If \p index equals the list size, this is effectively cxListAddArray().
   326  *
   327  * This method is usually more efficient than invoking cxListInsert()
   328  * multiple times.
   329  *
   330  * If there is not enough memory to add all elements, the returned value is
   331  * less than \p n.
   332  *
   333  * If this list is storing pointers instead of objects \p array is expected to
   334  * be an array of pointers.
   335  *
   336  * @param list the list
   337  * @param index the index where to add the elements
   338  * @param array a pointer to the elements to add
   339  * @param n the number of elements to add
   340  * @return the number of added elements
   341  */
   342 __attribute__((__nonnull__))
   343 static inline size_t cxListInsertArray(
   344         CxList *list,
   345         size_t index,
   346         void const *array,
   347         size_t n
   348 ) {
   349     return list->cl->insert_array(list, index, array, n);
   350 }
   352 /**
   353  * Inserts an element after the current location of the specified iterator.
   354  *
   355  * The used iterator remains operational, but all other active iterators should
   356  * be considered invalidated.
   357  *
   358  * If \p iter is not a list iterator, the behavior is undefined.
   359  * If \p iter is a past-the-end iterator, the new element gets appended to the list.
   360  *
   361  * @param iter an iterator
   362  * @param elem the element to insert
   363  * @return zero on success, non-zero on memory allocation failure
   364  * @see cxListInsert()
   365  * @see cxListInsertBefore()
   366  */
   367 __attribute__((__nonnull__))
   368 static inline int cxListInsertAfter(
   369         CxMutIterator *iter,
   370         void const *elem
   371 ) {
   372     return ((struct cx_list_s *) iter->src_handle)->cl->insert_iter(iter, elem, 0);
   373 }
   375 /**
   376  * Inserts an element before the current location of the specified iterator.
   377  *
   378  * The used iterator remains operational, but all other active iterators should
   379  * be considered invalidated.
   380  *
   381  * If \p iter is not a list iterator, the behavior is undefined.
   382  * If \p iter is a past-the-end iterator, the new element gets appended to the list.
   383  *
   384  * @param iter an iterator
   385  * @param elem the element to insert
   386  * @return zero on success, non-zero on memory allocation failure
   387  * @see cxListInsert()
   388  * @see cxListInsertAfter()
   389  */
   390 __attribute__((__nonnull__))
   391 static inline int cxListInsertBefore(
   392         CxMutIterator *iter,
   393         void const *elem
   394 ) {
   395     return ((struct cx_list_s *) iter->src_handle)->cl->insert_iter(iter, elem, 1);
   396 }
   398 /**
   399  * Removes the element at the specified index.
   400  * @param list the list
   401  * @param index the index of the element
   402  * @return zero on success, non-zero if the index is out of bounds
   403  */
   404 __attribute__((__nonnull__))
   405 static inline int cxListRemove(
   406         CxList *list,
   407         size_t index
   408 ) {
   409     return list->cl->remove(list, index);
   410 }
   412 /**
   413  * Swaps two items in the list.
   414  *
   415  * Implementations should only allocate temporary memory for the swap, if
   416  * it is necessary.
   417  *
   418  * @param list the list
   419  * @param i the index of the first element
   420  * @param j the index of the second element
   421  * @return zero on success, non-zero if one of the indices is out of bounds
   422  */
   423 __attribute__((__nonnull__))
   424 static inline int cxListSwap(
   425         CxList *list,
   426         size_t i,
   427         size_t j
   428 ) {
   429     return list->cl->swap(list, i, j);
   430 }
   432 /**
   433  * Returns a pointer to the element at the specified index.
   434  *
   435  * @param list the list
   436  * @param index the index of the element
   437  * @return a pointer to the element or \c NULL if the index is out of bounds
   438  */
   439 __attribute__((__nonnull__))
   440 static inline void *cxListAt(
   441         CxList *list,
   442         size_t index
   443 ) {
   444     return list->cl->at(list, index);
   445 }
   447 /**
   448  * Returns an iterator pointing to the item at the specified index.
   449  *
   450  * The returned iterator is position-aware.
   451  *
   452  * If the index is out of range, a past-the-end iterator will be returned.
   453  *
   454  * @param list the list
   455  * @param index the index where the iterator shall point at
   456  * @return a new iterator
   457  */
   458 __attribute__((__nonnull__, __warn_unused_result__))
   459 static inline CxIterator cxListIterator(
   460         CxList const *list,
   461         size_t index
   462 ) {
   463     return list->cl->iterator(list, index);
   464 }
   466 /**
   467  * Returns a mutating iterator pointing to the item at the specified index.
   468  *
   469  * The returned iterator is position-aware.
   470  *
   471  * If the index is out of range, a past-the-end iterator will be returned.
   472  *
   473  * @param list the list
   474  * @param index the index where the iterator shall point at
   475  * @return a new iterator
   476  */
   477 __attribute__((__nonnull__, __warn_unused_result__))
   478 CxMutIterator cxListMutIterator(
   479         CxList *list,
   480         size_t index
   481 );
   483 /**
   484  * Returns an iterator pointing to the first item of the list.
   485  *
   486  * The returned iterator is position-aware.
   487  *
   488  * If the list is empty, a past-the-end iterator will be returned.
   489  *
   490  * @param list the list
   491  * @return a new iterator
   492  */
   493 __attribute__((__nonnull__, __warn_unused_result__))
   494 static inline CxIterator cxListBegin(CxList const *list) {
   495     return list->cl->iterator(list, 0);
   496 }
   498 /**
   499  * Returns a mutating iterator pointing to the first item of the list.
   500  *
   501  * The returned iterator is position-aware.
   502  *
   503  * If the list is empty, a past-the-end iterator will be returned.
   504  *
   505  * @param list the list
   506  * @return a new iterator
   507  */
   508 __attribute__((__nonnull__, __warn_unused_result__))
   509 static inline CxMutIterator cxListBeginMut(CxList *list) {
   510     return cxListMutIterator(list, 0);
   511 }
   513 /**
   514  * Returns the index of the first element that equals \p elem.
   515  *
   516  * Determining equality is performed by the list's comparator function.
   517  *
   518  * @param list the list
   519  * @param elem the element to find
   520  * @return the index of the element or \c (size+1) if the element is not found
   521  */
   522 __attribute__((__nonnull__))
   523 static inline size_t cxListFind(
   524         CxList const *list,
   525         void const *elem
   526 ) {
   527     return list->cl->find(list, elem);
   528 }
   530 /**
   531  * Sorts the list in place.
   532  *
   533  * \remark The underlying sort algorithm is implementation defined.
   534  *
   535  * @param list the list
   536  */
   537 __attribute__((__nonnull__))
   538 static inline void cxListSort(CxList *list) {
   539     list->cl->sort(list);
   540 }
   542 /**
   543  * Reverses the order of the items.
   544  *
   545  * @param list the list
   546  */
   547 __attribute__((__nonnull__))
   548 static inline void cxListReverse(CxList *list) {
   549     list->cl->reverse(list);
   550 }
   552 /**
   553  * Compares a list to another list of the same type.
   554  *
   555  * First, the list sizes are compared.
   556  * If they match, the lists are compared element-wise.
   557  *
   558  * @param list the list
   559  * @param other the list to compare to
   560  * @return zero, if both lists are equal element wise,
   561  * negative if the first list is smaller, positive if the first list is larger
   562  */
   563 __attribute__((__nonnull__))
   564 int cxListCompare(
   565         CxList const *list,
   566         CxList const *other
   567 );
   569 /**
   570  * Deallocates the memory of the specified list structure.
   571  *
   572  * Also calls content a destructor function, depending on the configuration
   573  * in CxList.content_destructor_type.
   574  *
   575  * This function itself is a destructor function for the CxList.
   576  *
   577  * @param list the list which shall be destroyed
   578  */
   579 __attribute__((__nonnull__))
   580 void cxListDestroy(CxList *list);
   582 #ifdef __cplusplus
   583 } // extern "C"
   584 #endif
   586 #endif // UCX_LIST_H

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