/* * list.c: lists handling implementation * * Copyright (C) 2000 Gary Pennington and Daniel Veillard. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE AUTHORS AND * CONTRIBUTORS ACCEPT NO RESPONSIBILITY IN ANY CONCEIVABLE MANNER. * * Author: Gary.Pennington@uk.sun.com */ #define IN_LIBXML #include "libxml.h" #include <stdlib.h> #include <string.h> #include <libxml/xmlmemory.h> #include <libxml/list.h> #include <libxml/globals.h> /* * Type definition are kept internal */ struct _xmlLink { struct _xmlLink *next; struct _xmlLink *prev; void *data; }; struct _xmlList { xmlLinkPtr sentinel; void (*linkDeallocator)(xmlLinkPtr ); int (*linkCompare)(const void *, const void*); }; /************************************************************************ * * * Interfaces * * * ************************************************************************/ /** * xmlLinkDeallocator: * @l: a list * @lk: a link * * Unlink and deallocate @lk from list @l */ static void xmlLinkDeallocator(xmlListPtr l, xmlLinkPtr lk) { (lk->prev)->next = lk->next; (lk->next)->prev = lk->prev; if(l->linkDeallocator) l->linkDeallocator(lk); xmlFree(lk); } /** * xmlLinkCompare: * @data0: first data * @data1: second data * * Compares two arbitrary data * * Returns -1, 0 or 1 depending on whether data1 is greater equal or smaller * than data0 */ static int xmlLinkCompare(const void *data0, const void *data1) { if (data0 < data1) return (-1); else if (data0 == data1) return (0); return (1); } /** * xmlListLowerSearch: * @l: a list * @data: a data * * Search data in the ordered list walking from the beginning * * Returns the link containing the data or NULL */ static xmlLinkPtr xmlListLowerSearch(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(NULL); for(lk = l->sentinel->next;lk != l->sentinel && l->linkCompare(lk->data, data) <0 ;lk = lk->next); return lk; } /** * xmlListHigherSearch: * @l: a list * @data: a data * * Search data in the ordered list walking backward from the end * * Returns the link containing the data or NULL */ static xmlLinkPtr xmlListHigherSearch(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(NULL); for(lk = l->sentinel->prev;lk != l->sentinel && l->linkCompare(lk->data, data) >0 ;lk = lk->prev); return lk; } /** * xmlListSearch: * @l: a list * @data: a data * * Search data in the list * * Returns the link containing the data or NULL */ static xmlLinkPtr xmlListLinkSearch(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(NULL); lk = xmlListLowerSearch(l, data); if (lk == l->sentinel) return NULL; else { if (l->linkCompare(lk->data, data) ==0) return lk; return NULL; } } /** * xmlListLinkReverseSearch: * @l: a list * @data: a data * * Search data in the list processing backward * * Returns the link containing the data or NULL */ static xmlLinkPtr xmlListLinkReverseSearch(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(NULL); lk = xmlListHigherSearch(l, data); if (lk == l->sentinel) return NULL; else { if (l->linkCompare(lk->data, data) ==0) return lk; return NULL; } } /** * xmlListCreate: * @deallocator: an optional deallocator function * @compare: an optional comparison function * * Create a new list * * Returns the new list or NULL in case of error */ xmlListPtr xmlListCreate(xmlListDeallocator deallocator, xmlListDataCompare compare) { xmlListPtr l; if (NULL == (l = (xmlListPtr )xmlMalloc( sizeof(xmlList)))) { xmlGenericError(xmlGenericErrorContext, "Cannot initialize memory for list"); return (NULL); } /* Initialize the list to NULL */ memset(l, 0, sizeof(xmlList)); /* Add the sentinel */ if (NULL ==(l->sentinel = (xmlLinkPtr )xmlMalloc(sizeof(xmlLink)))) { xmlGenericError(xmlGenericErrorContext, "Cannot initialize memory for sentinel"); xmlFree(l); return (NULL); } l->sentinel->next = l->sentinel; l->sentinel->prev = l->sentinel; l->sentinel->data = NULL; /* If there is a link deallocator, use it */ if (deallocator != NULL) l->linkDeallocator = deallocator; /* If there is a link comparator, use it */ if (compare != NULL) l->linkCompare = compare; else /* Use our own */ l->linkCompare = xmlLinkCompare; return l; } /** * xmlListSearch: * @l: a list * @data: a search value * * Search the list for an existing value of @data * * Returns the value associated to @data or NULL in case of error */ void * xmlListSearch(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(NULL); lk = xmlListLinkSearch(l, data); if (lk) return (lk->data); return NULL; } /** * xmlListReverseSearch: * @l: a list * @data: a search value * * Search the list in reverse order for an existing value of @data * * Returns the value associated to @data or NULL in case of error */ void * xmlListReverseSearch(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(NULL); lk = xmlListLinkReverseSearch(l, data); if (lk) return (lk->data); return NULL; } /** * xmlListInsert: * @l: a list * @data: the data * * Insert data in the ordered list at the beginning for this value * * Returns 0 in case of success, 1 in case of failure */ int xmlListInsert(xmlListPtr l, void *data) { xmlLinkPtr lkPlace, lkNew; if (l == NULL) return(1); lkPlace = xmlListLowerSearch(l, data); /* Add the new link */ lkNew = (xmlLinkPtr) xmlMalloc(sizeof(xmlLink)); if (lkNew == NULL) { xmlGenericError(xmlGenericErrorContext, "Cannot initialize memory for new link"); return (1); } lkNew->data = data; lkPlace = lkPlace->prev; lkNew->next = lkPlace->next; (lkPlace->next)->prev = lkNew; lkPlace->next = lkNew; lkNew->prev = lkPlace; return 0; } /** * xmlListAppend: * @l: a list * @data: the data * * Insert data in the ordered list at the end for this value * * Returns 0 in case of success, 1 in case of failure */ int xmlListAppend(xmlListPtr l, void *data) { xmlLinkPtr lkPlace, lkNew; if (l == NULL) return(1); lkPlace = xmlListHigherSearch(l, data); /* Add the new link */ lkNew = (xmlLinkPtr) xmlMalloc(sizeof(xmlLink)); if (lkNew == NULL) { xmlGenericError(xmlGenericErrorContext, "Cannot initialize memory for new link"); return (1); } lkNew->data = data; lkNew->next = lkPlace->next; (lkPlace->next)->prev = lkNew; lkPlace->next = lkNew; lkNew->prev = lkPlace; return 0; } /** * xmlListDelete: * @l: a list * * Deletes the list and its associated data */ void xmlListDelete(xmlListPtr l) { if (l == NULL) return; xmlListClear(l); xmlFree(l->sentinel); xmlFree(l); } /** * xmlListRemoveFirst: * @l: a list * @data: list data * * Remove the first instance associated to data in the list * * Returns 1 if a deallocation occured, or 0 if not found */ int xmlListRemoveFirst(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(0); /*Find the first instance of this data */ lk = xmlListLinkSearch(l, data); if (lk != NULL) { xmlLinkDeallocator(l, lk); return 1; } return 0; } /** * xmlListRemoveLast: * @l: a list * @data: list data * * Remove the last instance associated to data in the list * * Returns 1 if a deallocation occured, or 0 if not found */ int xmlListRemoveLast(xmlListPtr l, void *data) { xmlLinkPtr lk; if (l == NULL) return(0); /*Find the last instance of this data */ lk = xmlListLinkReverseSearch(l, data); if (lk != NULL) { xmlLinkDeallocator(l, lk); return 1; } return 0; } /** * xmlListRemoveAll: * @l: a list * @data: list data * * Remove the all instance associated to data in the list * * Returns the number of deallocation, or 0 if not found */ int xmlListRemoveAll(xmlListPtr l, void *data) { int count=0; if (l == NULL) return(0); while(xmlListRemoveFirst(l, data)) count++; return count; } /** * xmlListClear: * @l: a list * * Remove the all data in the list */ void xmlListClear(xmlListPtr l) { xmlLinkPtr lk; if (l == NULL) return; lk = l->sentinel->next; while(lk != l->sentinel) { xmlLinkPtr next = lk->next; xmlLinkDeallocator(l, lk); lk = next; } } /** * xmlListEmpty: * @l: a list * * Is the list empty ? * * Returns 1 if the list is empty, 0 if not empty and -1 in case of error */ int xmlListEmpty(xmlListPtr l) { if (l == NULL) return(-1); return (l->sentinel->next == l->sentinel); } /** * xmlListFront: * @l: a list * * Get the first element in the list * * Returns the first element in the list, or NULL */ xmlLinkPtr xmlListFront(xmlListPtr l) { if (l == NULL) return(NULL); return (l->sentinel->next); } /** * xmlListEnd: * @l: a list * * Get the last element in the list * * Returns the last element in the list, or NULL */ xmlLinkPtr xmlListEnd(xmlListPtr l) { if (l == NULL) return(NULL); return (l->sentinel->prev); } /** * xmlListSize: * @l: a list * * Get the number of elements in the list * * Returns the number of elements in the list or -1 in case of error */ int xmlListSize(xmlListPtr l) { xmlLinkPtr lk; int count=0; if (l == NULL) return(-1); /* TODO: keep a counter in xmlList instead */ for(lk = l->sentinel->next; lk != l->sentinel; lk = lk->next, count++); return count; } /** * xmlListPopFront: * @l: a list * * Removes the first element in the list */ void xmlListPopFront(xmlListPtr l) { if(!xmlListEmpty(l)) xmlLinkDeallocator(l, l->sentinel->next); } /** * xmlListPopBack: * @l: a list * * Removes the last element in the list */ void xmlListPopBack(xmlListPtr l) { if(!xmlListEmpty(l)) xmlLinkDeallocator(l, l->sentinel->prev); } /** * xmlListPushFront: * @l: a list * @data: new data * * add the new data at the beginning of the list * * Returns 1 if successful, 0 otherwise */ int xmlListPushFront(xmlListPtr l, void *data) { xmlLinkPtr lkPlace, lkNew; if (l == NULL) return(0); lkPlace = l->sentinel; /* Add the new link */ lkNew = (xmlLinkPtr) xmlMalloc(sizeof(xmlLink)); if (lkNew == NULL) { xmlGenericError(xmlGenericErrorContext, "Cannot initialize memory for new link"); return (0); } lkNew->data = data; lkNew->next = lkPlace->next; (lkPlace->next)->prev = lkNew; lkPlace->next = lkNew; lkNew->prev = lkPlace; return 1; } /** * xmlListPushBack: * @l: a list * @data: new data * * add the new data at the end of the list * * Returns 1 if successful, 0 otherwise */ int xmlListPushBack(xmlListPtr l, void *data) { xmlLinkPtr lkPlace, lkNew; if (l == NULL) return(0); lkPlace = l->sentinel->prev; /* Add the new link */ if (NULL ==(lkNew = (xmlLinkPtr )xmlMalloc(sizeof(xmlLink)))) { xmlGenericError(xmlGenericErrorContext, "Cannot initialize memory for new link"); return (0); } lkNew->data = data; lkNew->next = lkPlace->next; (lkPlace->next)->prev = lkNew; lkPlace->next = lkNew; lkNew->prev = lkPlace; return 1; } /** * xmlLinkGetData: * @lk: a link * * See Returns. * * Returns a pointer to the data referenced from this link */ void * xmlLinkGetData(xmlLinkPtr lk) { if (lk == NULL) return(NULL); return lk->data; } /** * xmlListReverse: * @l: a list * * Reverse the order of the elements in the list */ void xmlListReverse(xmlListPtr l) { xmlLinkPtr lk; xmlLinkPtr lkPrev; if (l == NULL) return; lkPrev = l->sentinel; for (lk = l->sentinel->next; lk != l->sentinel; lk = lk->next) { lkPrev->next = lkPrev->prev; lkPrev->prev = lk; lkPrev = lk; } /* Fix up the last node */ lkPrev->next = lkPrev->prev; lkPrev->prev = lk; } /** * xmlListSort: * @l: a list * * Sort all the elements in the list */ void xmlListSort(xmlListPtr l) { xmlListPtr lTemp; if (l == NULL) return; if(xmlListEmpty(l)) return; /* I think that the real answer is to implement quicksort, the * alternative is to implement some list copying procedure which * would be based on a list copy followed by a clear followed by * an insert. This is slow... */ if (NULL ==(lTemp = xmlListDup(l))) return; xmlListClear(l); xmlListMerge(l, lTemp); xmlListDelete(lTemp); return; } /** * xmlListWalk: * @l: a list * @walker: a processing function * @user: a user parameter passed to the walker function * * Walk all the element of the first from first to last and * apply the walker function to it */ void xmlListWalk(xmlListPtr l, xmlListWalker walker, const void *user) { xmlLinkPtr lk; if ((l == NULL) || (walker == NULL)) return; for(lk = l->sentinel->next; lk != l->sentinel; lk = lk->next) { if((walker(lk->data, user)) == 0) break; } } /** * xmlListReverseWalk: * @l: a list * @walker: a processing function * @user: a user parameter passed to the walker function * * Walk all the element of the list in reverse order and * apply the walker function to it */ void xmlListReverseWalk(xmlListPtr l, xmlListWalker walker, const void *user) { xmlLinkPtr lk; if ((l == NULL) || (walker == NULL)) return; for(lk = l->sentinel->prev; lk != l->sentinel; lk = lk->prev) { if((walker(lk->data, user)) == 0) break; } } /** * xmlListMerge: * @l1: the original list * @l2: the new list * * include all the elements of the second list in the first one and * clear the second list */ void xmlListMerge(xmlListPtr l1, xmlListPtr l2) { xmlListCopy(l1, l2); xmlListClear(l2); } /** * xmlListDup: * @old: the list * * Duplicate the list * * Returns a new copy of the list or NULL in case of error */ xmlListPtr xmlListDup(const xmlListPtr old) { xmlListPtr cur; if (old == NULL) return(NULL); /* Hmmm, how to best deal with allocation issues when copying * lists. If there is a de-allocator, should responsibility lie with * the new list or the old list. Surely not both. I'll arbitrarily * set it to be the old list for the time being whilst I work out * the answer */ if (NULL ==(cur = xmlListCreate(NULL, old->linkCompare))) return (NULL); if (0 != xmlListCopy(cur, old)) return NULL; return cur; } /** * xmlListCopy: * @cur: the new list * @old: the old list * * Move all the element from the old list in the new list * * Returns 0 in case of success 1 in case of error */ int xmlListCopy(xmlListPtr cur, const xmlListPtr old) { /* Walk the old tree and insert the data into the new one */ xmlLinkPtr lk; if ((old == NULL) || (cur == NULL)) return(1); for(lk = old->sentinel->next; lk != old->sentinel; lk = lk->next) { if (0 !=xmlListInsert(cur, lk->data)) { xmlListDelete(cur); return (1); } } return (0); } /* xmlListUnique() */ /* xmlListSwap */ #define bottom_list #include "elfgcchack.h"