1 #ifndef _IPXE_JUMPSCROLL_H
2 #define _IPXE_JUMPSCROLL_H
3 
4 /** @file
5  *
6  * Jump scrolling
7  *
8  */
9 
10 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
11 
12 /** A jump scroller */
13 struct jump_scroller {
14 	/** Maximum number of visible rows */
15 	unsigned int rows;
16 	/** Total number of items */
17 	unsigned int count;
18 	/** Currently selected item */
19 	unsigned int current;
20 	/** First visible item */
21 	unsigned int first;
22 };
23 
24 /**
25  * Check if jump scroller is currently on first page
26  *
27  * @v scroll		Jump scroller
28  * @ret is_first	Scroller is currently on first page
29  */
jump_scroll_is_first(struct jump_scroller * scroll)30 static inline int jump_scroll_is_first ( struct jump_scroller *scroll ) {
31 
32 	return ( scroll->first == 0 );
33 }
34 
35 /**
36  * Check if jump scroller is currently on last page
37  *
38  * @v scroll		Jump scroller
39  * @ret is_last		Scroller is currently on last page
40  */
jump_scroll_is_last(struct jump_scroller * scroll)41 static inline int jump_scroll_is_last ( struct jump_scroller *scroll ) {
42 
43 	return ( ( scroll->first + scroll->rows ) >= scroll->count );
44 }
45 
46 extern int jump_scroll_key ( struct jump_scroller *scroll, int key );
47 extern int jump_scroll_move ( struct jump_scroller *scroll, int move );
48 extern int jump_scroll ( struct jump_scroller *scroll );
49 
50 #endif /* _IPXE_JUMPSCROLL_H */
51