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/* A small List class HTList.c
** ==================
**
** A list is represented as a sequence of linked nodes of type HTList.
** The first node is a header which contains no object.
** New nodes are inserted between the header and the rest of the list.
*/
#include "HTUtils.h"
#include "HTList.h"
/*#include <stdio.h> included by HTUtils.h -- FM *//* joe@athena, TBL 921019 */
#include "LYLeaks.h"
#define FREE(x) if (x) {free(x); x = NULL;}
/* Create list.
*/
PUBLIC HTList * HTList_new NOARGS
{
HTList *newList;
if ((newList = (HTList *)calloc(1, sizeof(HTList))) == NULL)
outofmem(__FILE__, "HTList_new");
newList->object = NULL;
newList->next = NULL;
return newList;
}
/* Delete list.
*/
PUBLIC void HTList_delete ARGS1(
HTList *, me)
{
HTList *current;
while ((current = me)) {
me = me->next;
FREE (current);
}
return;
}
/* Add object to START of list (so it is pointed to by the head).
*/
PUBLIC void HTList_addObject ARGS2(
HTList *, me,
void *, newObject)
{
HTList *newNode;
if (me) {
if ((newNode = (HTList *)calloc(1, sizeof(HTList))) == NULL)
outofmem(__FILE__, "HTList_addObject");
newNode->object = newObject;
newNode->next = me->next;
me->next = newNode;
} else if (TRACE) {
fprintf(stderr,
"HTList: Trying to add object %p to a nonexisting list\n",
newObject);
}
return;
}
/* Append object to END of list (furthest from the head).
*/
PUBLIC void HTList_appendObject ARGS2(
HTList *, me,
void *, newObject)
{
HTList *temp = me;
if (temp && newObject) {
while (temp->next)
temp = temp->next;
HTList_addObject(temp, newObject);
}
return;
}
/* Insert an object into the list at a specified position.
** If position is 0, this places the object at the head of the list
** and is equivalent to HTList_addObject().
*/
PUBLIC void HTList_insertObjectAt ARGS3(
HTList *, me,
void *, newObject,
int, pos)
{
HTList * newNode;
HTList * temp = me;
HTList * prevNode;
int Pos = pos;
if (!temp) {
if (TRACE) {
fprintf(stderr,
"HTList: Trying to add object %p to a nonexisting list\n",
newObject);
}
return;
}
if (Pos < 0) {
Pos = 0;
if (TRACE) {
fprintf(stderr,
"HTList: Treating negative object position %d as %d.\n",
pos, Pos);
}
}
prevNode = temp;
while ((temp = temp->next)) {
if (Pos == 0) {
if ((newNode = (HTList *)calloc(1, sizeof(HTList))) == NULL)
outofmem(__FILE__, "HTList_addObjectAt");
newNode->object = newObject;
newNode->next = temp;
if (prevNode)
prevNode->next = newNode;
return;
}
prevNode = temp;
Pos--;
}
if (Pos >= 0)
HTList_addObject(prevNode, newObject);
return;
}
/* Remove specified object from list.
*/
PUBLIC BOOL HTList_removeObject ARGS2(
HTList *, me,
void *, oldObject)
{
HTList *temp = me;
HTList *prevNode;
if (temp && oldObject) {
while (temp->next) {
prevNode = temp;
temp = temp->next;
if (temp->object == oldObject) {
prevNode->next = temp->next;
FREE (temp);
return YES; /* Success */
}
}
}
return NO; /* object not found or NULL list */
}
/* Remove object at a given position in the list, where 0 is the
** object pointed to by the head (returns a pointer to the element
** (->object) for the object, and NULL if the list is empty, or
** if it doesn't exist - Yuk!).
*/
PUBLIC void * HTList_removeObjectAt ARGS2(
HTList *, me,
int, position)
{
HTList * temp = me;
HTList * prevNode;
int pos = position;
if (!temp || pos < 0)
return NULL;
prevNode = temp;
while ((temp = temp->next)) {
if (pos == 0) {
prevNode->next = temp->next;
prevNode = temp;
FREE(temp);
return prevNode->object;
}
prevNode = temp;
pos--;
}
return NULL; /* Reached the end of the list */
}
/* Remove object from START of list (the Last one inserted
** via HTList_addObject(), and pointed to by the head).
*/
PUBLIC void * HTList_removeLastObject ARGS1(
HTList *, me)
{
HTList * lastNode;
void * lastObject;
if (me && me->next) {
lastNode = me->next;
lastObject = lastNode->object;
me->next = lastNode->next;
FREE (lastNode);
return lastObject;
} else { /* Empty list */
return NULL;
}
}
/* Remove object from END of list (the First one inserted
** via HTList_addObject(), and furthest from the head).
*/
PUBLIC void * HTList_removeFirstObject ARGS1(
HTList *, me)
{
HTList * temp = me;
HTList * prevNode;
void *firstObject;
if (!temp)
return NULL;
prevNode = temp;
if (temp->next) {
while (temp->next) {
prevNode = temp;
temp = temp->next;
}
firstObject = temp->object;
prevNode->next = NULL;
FREE (temp);
return firstObject;
} else { /* Empty list */
return NULL;
}
}
/* Determine total number of objects in the list,
** not counting the head.
*/
PUBLIC int HTList_count ARGS1(
HTList *, me)
{
HTList * temp = me;
int count = 0;
if (temp)
while ((temp = temp->next))
count++;
return count;
}
/* Determine position of an object in the list (a value of 0
** means it is pointed to by the head; returns -1 if not found).
*/
PUBLIC int HTList_indexOf ARGS2(
HTList *, me,
void *, object)
{
HTList * temp = me;
int position = 0;
if (temp) {
while ((temp = temp->next)) {
if (temp->object == object)
return position;
position++;
}
}
return -1; /* Object not in the list */
}
/* Return pointer to the object at a specified position in the list,
** where 0 is the object pointed to by the head (returns NULL if
** the list is empty, or if it doesn't exist - Yuk!).
*/
PUBLIC void * HTList_objectAt ARGS2(
HTList *, me,
int, position)
{
HTList * temp = me;
int pos = position;
if (!temp || pos < 0)
return NULL;
while ((temp = temp->next)) {
if (pos == 0)
return temp->object;
pos--;
}
return NULL; /* Reached the end of the list */
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.