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#include "HTUtils.h"
#include "tcp.h" /* for standard io */
#include "HTHistory.h"
#include "LYLeaks.h"
static HTList * history; /* List of visited anchors */
/* Navigation
** ==========
*/
/* Record the jump to an anchor
** ----------------------------
*/
void HTHistory_record
ARGS1 (HTAnchor *,destination)
{
if (destination) {
if (! history)
history = HTList_new();
HTList_addObject (history, destination);
}
}
/* Go back in history (find the last visited node)
** ------------------
*/
HTAnchor * HTHistory_backtrack
NOARGS /* FIXME: Should we add a `sticky' option ? */
{
if (HTHistory_canBacktrack())
HTList_removeLastObject(history);
return(HTAnchor *)HTList_lastObject(history); /* is Home if can't backtrack */
}
BOOL HTHistory_canBacktrack
NOARGS
{
return (HTList_objectAt (history, 1) != NULL);
}
/* Browse through references in the same parent node
** -------------------------------------------------
**
** Take the n-th child's link after or before the one we took to get here.
** Positive offset means go towards most recently added children.
*/
HTAnchor * HTHistory_moveBy
ARGS1 (int,offset)
{
HTAnchor * last = (HTAnchor *)HTList_objectAt (history, 1);
if (! last)
return NULL; /* No last visited node */
if (last != (HTAnchor *) last->parent) { /* Was a child */
HTList * kids = last->parent->children;
int i = HTList_indexOf (kids, last);
HTAnchor * nextOne = (HTAnchor *)HTList_objectAt (kids, i - offset);
if (nextOne) {
HTAnchor * destination = HTAnchor_followMainLink (nextOne);
if (destination) {
HTList_removeLastObject (history);
HTList_removeLastObject (history);
HTList_addObject (history, nextOne);
HTList_addObject (history, destination);
}
return destination;
} else {
if (TRACE) fprintf(stderr,
"HTHistory_moveBy: offset by %+d goes out of list %p.\n",
offset, (void*)kids);
return NULL;
}
} else { /* Was a parent */
return NULL; /* FIXME we could possibly follow the next link... */
}
}
BOOL HTHistory_canMoveBy
ARGS1 (int,offset)
{
HTAnchor * last = (HTAnchor *)HTList_objectAt (history, 1);
if (! last)
return NO; /* No last visited node */
if (last != (HTAnchor *) last->parent) { /* Was a child */
HTList * kids = last->parent->children;
int i = HTList_indexOf (kids, last);
return (HTList_objectAt (kids, i - offset) != NULL);
} else { /* Was a parent */
return NO; /* FIXME we could possibly follow the next link... */
}
}
/* Retrieval
** =========
*/
/* Read numbered visited anchor (1 is the oldest)
** ----------------------------
*/
HTAnchor * HTHistory_read
ARGS1 (int,number)
{
return (HTAnchor *)HTList_objectAt(history, HTList_count (history) - number);
}
/* Recall numbered visited anchor (1 is the oldest)
** ------------------------------
** This reads the anchor and stores it again in the list, except if last.
*/
HTAnchor * HTHistory_recall
ARGS1 (int,number)
{
HTAnchor * destination =
(HTAnchor *)HTList_objectAt (history, HTList_count (history) - number);
if (destination && destination != (HTAnchor *)HTList_lastObject (history))
HTList_addObject (history, destination);
return destination;
}
/* Number of Anchors stored
** ------------------------
**
** This is needed in order to check the validity of certain commands
** for menus, etc.
(not needed for now. Use canBacktrack, etc.)
int HTHistory_count
NOARGS
{
return HTList_count (history);
}
*/
/* Change last history entry
** -------------------------
**
** Sometimes we load a node by one anchor but leave by a different
** one, and it is the one we left from which we want to remember.
*/
void HTHistory_leavingFrom
ARGS1 (HTAnchor *,anchor)
{
if (HTList_removeLastObject (history))
HTList_addObject (history, anchor);
else
if (TRACE) fprintf(stderr, "HTHistory_leavingFrom: empty history !\n");
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.