selection.c

来自「用于nano-x的xlib」· C语言 代码 · 共 82 行

/* Copyright 2003, Jordan Crouse ([e-mail]) */

#include "nxlib.h"

/* Het another dummy storage area.  We hold onto the value and
   return them when XGetSelectionOwner says so

   It seems that selections live forever - I don't see any way to
   remove them.  That's odd to me, but oh, well......
*/

struct sstruct {
	Atom selection;
	Window owner;
	Time time;
	struct ssstruct *next;
};

static struct sstruct *select_list = 0;

int XSetSelectionOwner(Display *display, Atom selection, Window owner, Time t) {
	
	struct sstruct *select = select_list;
	struct sstruct *prev = 0;
	
	for( ; select; prev = select, select = select->next) 
		if (select->selection == selection) {
			if (t > select->time) { 
				select->owner = owner;   /* Note:  SelectionClear event should get generated here */
				select->time = (t == CurrentTime) ? time(0) : t;
			}
			
			return 0;
		}
	
	select = (struct sstruct *) malloc(sizeof(struct sstruct));
	select->selection = selection;
	select->owner = owner;
	select->time = (t == CurrentTime) ? time(0) : t;
	select->next = 0;

	if (!prev) select_list = select;
	else prev->next = select;

	return 0;
}

static struct sstruct *find_selection(Atom selection) {
	struct sstruct *select = select_list;
	
	for (; select; select = select->next) 
		if (select->selection == selection) return select;
	return 0;
}

Window XGetSelectionOwner(Display *display, Atom selection) {
	struct sstruct *select = find_selection(selection);
	return (select) ? select->owner : None;
}

/* Move selection to target.  There are lots of events that might be generated here, but for now we won't
   worry about those. 
*/

int XConvertSelection(Display *display, Atom selection, Atom target, Atom property, Window requestor, Time t) {
	struct sstruct *select = find_selection(selection);
	
	select->selection = target;
	select->time = (t == CurrentTime) ? time(0) : t;

	/* We should generate a SelectionRequest event to the owner in this 
	   situation, or if there is no owner, then a SelectionNotify 
	   to the requestor 
	*/

	return 0;
}