cLinkedList.c

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#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include "../include/cLinkedList.h"
#include "../include/macrodef.h"
 
#ifdef __cplusplus 
extern "C" {
#endif 
 
/********************************/
/* Linked list status functions */
/********************************/
 
unsigned long cListLength (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListLength): WARNING - Quashed attempt to access NULL pointer.\n");
        return 0;
    }
    return myList->num_elem;
}
 
int cListEmpty (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListEmpty): WARNING - Quashed attempt to access NULL pointer.\n");
        return FALSE;
    }else if (myList->num_elem > 0) {
        return FALSE;
    }
    return TRUE;
}
 
 
/******************************/
/* Linked list read functions */
/******************************/
cListElem * cListFirstElem (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListFirstElem): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    return myList->anchor.nextElem;
}
 
cListElem * cListLastElem (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListLastElem): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    return myList->anchor.prevElem;
}
 
cListElem * cListNextElem (cLinkedList *myList, cListElem *myElem)
{
    if (myList == NULL || myElem == NULL) {
        if (myList == NULL)
            fprintf(ERRSTREAM, "cLinkedList (cListNextElem): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    } else if ((myList->num_elem == 0) || (myList->anchor.prevElem == myElem)) {
        return NULL;
    }
    return myElem->nextElem;
}
 
cListElem * cListPrevElem (cLinkedList *myList, cListElem *myElem)
{
    if (myList == NULL || myElem == NULL) {
        if(myList == NULL)
            fprintf(ERRSTREAM, "cLinkedList (cListPrevElem): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    } else if ((myList->num_elem == 0) || (myList->anchor.nextElem == myElem)) {
        return NULL;
    }
    return myElem->prevElem;
}
 
cListElem * cListFindElem (cLinkedList *myList, void *myData)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListFindElem): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    cListElem *myElem = NULL;
    for (myElem = cListFirstElem(myList); myElem != NULL ; myElem = cListNextElem(myList, myElem)) {
        if (myElem->obj == myData) {
            return myElem;
        }
    }
    return myElem;
}
 
void * cListFindData (cLinkedList *myList, void *myData)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListFindData): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    cListElem *elem = cListFindElem(myList, myData);
    if (elem == NULL)
        return NULL;
    else
        return elem->obj;
}
 
void * cListFirstData (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListFirstData): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    cListElem *elem = (cListFirstElem(myList));
    if (elem == NULL)
        return NULL;
    else
        return elem->obj;
}
 
void * cListLastData (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListLastData): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    cListElem *elem = (cListLastElem(myList));
    if (elem == NULL)
        return NULL;
    else
        return elem->obj;
}
 
void * cListNextData (cLinkedList *myList, void *myData)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListNextData): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    cListElem *elem = cListNextElem(myList, cListFindElem(myList, myData));
    if (elem == NULL)
        return NULL;
    else
        return elem->obj;
}
 
void * cListPrevData(cLinkedList *myList, void *myData)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListPrevData): WARNING - Quashed attempt to access NULL pointer.\n");
        return NULL;
    }
    cListElem *elem = cListPrevElem(myList, cListFindElem(myList, myData));
    if (elem == NULL)
        return NULL;
    else
        return elem->obj;
}
 
 
/**********************************/
/* Linked list creation functions */
/**********************************/
int cListInit (cLinkedList *myList)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListInit): WARNING - Quashed attempt to access NULL pointer.\n");
        return 0;
    }
 
    myList->num_elem        = 0;
 
    myList->anchor.prevElem = NULL;
    myList->anchor.nextElem = NULL;
    myList->anchor.obj      = NULL;
 
    return 1;
}
 
int cListInsertAfter (cLinkedList *myList, void *newData, cListElem *elem)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListInsertAfter): WARNING - Quashed attempt to access NULL pointer.\n");
        return 0;
    }
    cListElem *newElem = (cListElem *)malloc(sizeof(cListElem));
    if (cListEmpty(myList)) {
        myList->anchor.prevElem = newElem;
        myList->anchor.nextElem = newElem;
        newElem->prevElem       = newElem;
        newElem->nextElem       = &(myList->anchor);
    } else {
        newElem->prevElem           = elem;
        newElem->nextElem           = elem->nextElem;
        (elem->nextElem)->prevElem  = newElem;
         elem->nextElem             = newElem;
    }
    newElem->obj      = newData;
    myList->num_elem += 1;
    return 1;
}
 
int cListInsertBefore (cLinkedList *myList, void *newData, cListElem *elem)
{
    if (myList == NULL) {
        fprintf(ERRSTREAM, "cLinkedList (cListInsertAfter): WARNING - Quashed attempt to access NULL pointer.\n");
        return 0;
    }
    cListElem *newElem = (cListElem *)malloc(sizeof(cListElem));
    if (cListEmpty(myList)) {
        myList->anchor.prevElem = newElem;
        myList->anchor.nextElem = newElem;
        newElem->prevElem       = newElem;
        newElem->nextElem       = &(myList->anchor);
    } else {
        newElem->prevElem           = elem->prevElem;
        newElem->nextElem           = elem;
        (elem->prevElem)->nextElem  = newElem;
        elem->prevElem              = newElem;
    }
    newElem->obj      = newData;
    myList->num_elem += 1;
    return 1;
}
 
int cListAppend (cLinkedList *myList, void *newData)
{
    return cListInsertAfter(myList, newData, myList->anchor.prevElem);
}
 
int cListPrepend (cLinkedList *myList, void *newData) {
    return cListInsertBefore(myList, newData, myList->anchor.nextElem);
}
 
/********************************/
/* Linked list unlink functions */
/********************************/
 void cListUnlinkElem (cLinkedList *myList, cListElem *delElem)
{
    if (myList->num_elem > 0 && delElem != NULL) {
        (delElem->prevElem)->nextElem = delElem->nextElem;
        (delElem->nextElem)->prevElem = delElem->prevElem;
        myList->num_elem -= 1;
 
        free(delElem);
        delElem = NULL;
    } else if (delElem == NULL) {
        fprintf(ERRSTREAM, "cListUnlinkElem (cLinkedList): WARNING - Quashed attempt to de-reference a NULL pointer!\n");
    } else {
        fprintf(ERRSTREAM, "cListUnlinkElem (cLinkedList): WARNING - Quashed attempt to access empty linked list.\n");
    }
 
    if (cListEmpty(myList)) {
        cListInit(myList);
    }
}
 
void cListUnlinkAll (cLinkedList *myList)
{
    cListElem *elem = cListFirstElem(myList);
    cListElem *nextElem = cListNextElem(myList, elem);
 
    while (elem != NULL) {
        cListUnlinkElem(myList, elem);
        elem = nextElem;
        nextElem = cListNextElem(myList, elem);
    }
}
 
void cListUnlinkData (cLinkedList *delList, void *delData)
{
    cListUnlinkElem(delList, cListFindElem(delList, delData));
}
 
#ifdef __cplusplus 
}
#endif