1 d957951b 2005-02-11 devnull #include <u.h>
 2 d957951b 2005-02-11 devnull #include <libc.h>
 3 d957951b 2005-02-11 devnull #include <bio.h>
 4 d957951b 2005-02-11 devnull #include <ndb.h>
 5 d957951b 2005-02-11 devnull 
 6 d957951b 2005-02-11 devnull /*
 7 d957951b 2005-02-11 devnull  *  reorder the tuple to put x's line first in the entry and x fitst in its line
 8 d957951b 2005-02-11 devnull  */
 9 d957951b 2005-02-11 devnull Ndbtuple*
10 d957951b 2005-02-11 devnull ndbreorder(Ndbtuple *t, Ndbtuple *x)
11 d957951b 2005-02-11 devnull {
12 d957951b 2005-02-11 devnull 	Ndbtuple *nt;
13 d957951b 2005-02-11 devnull 	Ndbtuple *last, *prev;
14 d957951b 2005-02-11 devnull 
15 d957951b 2005-02-11 devnull 	/* if x is first, we're done */
16 d957951b 2005-02-11 devnull 	if(x == t)
17 d957951b 2005-02-11 devnull 		return t;
18 d957951b 2005-02-11 devnull 
19 d957951b 2005-02-11 devnull 	/* find end of x's line */
20 d957951b 2005-02-11 devnull 	for(last = x; last->line == last->entry; last = last->line)
21 d957951b 2005-02-11 devnull 		;
22 d957951b 2005-02-11 devnull 
23 d957951b 2005-02-11 devnull 	/* rotate to make this line first */
24 d957951b 2005-02-11 devnull 	if(last->line != t){
25 d957951b 2005-02-11 devnull 
26 d957951b 2005-02-11 devnull 		/* detach this line and everything after it from the entry */
27 d957951b 2005-02-11 devnull 		for(nt = t; nt->entry != last->line; nt = nt->entry)
28 d957951b 2005-02-11 devnull 			;
29 d957951b 2005-02-11 devnull 		nt->entry = nil;
30 fa325e9b 2020-01-10 cross 
31 d957951b 2005-02-11 devnull 		/* switch */
32 d957951b 2005-02-11 devnull 		for(nt = last; nt->entry != nil; nt = nt->entry)
33 d957951b 2005-02-11 devnull 			;
34 d957951b 2005-02-11 devnull 		nt->entry = t;
35 d957951b 2005-02-11 devnull 	}
36 d957951b 2005-02-11 devnull 
37 d957951b 2005-02-11 devnull 	/* rotate line to make x first */
38 d957951b 2005-02-11 devnull 	if(x != last->line){
39 d957951b 2005-02-11 devnull 
40 d957951b 2005-02-11 devnull 		/* find entry before x */
41 6c7443a6 2014-10-21 0intro 		for(prev = last; prev->line != x; prev = prev->line)
42 d957951b 2005-02-11 devnull 			;
43 d957951b 2005-02-11 devnull 
44 d957951b 2005-02-11 devnull 		/* detach line */
45 d957951b 2005-02-11 devnull 		nt = last->entry;
46 d957951b 2005-02-11 devnull 		last->entry = last->line;
47 d957951b 2005-02-11 devnull 
48 d957951b 2005-02-11 devnull 		/* reattach */
49 d957951b 2005-02-11 devnull 		prev->entry = nt;
50 d957951b 2005-02-11 devnull 	}
51 d957951b 2005-02-11 devnull 
52 d957951b 2005-02-11 devnull 	return x;
53 d957951b 2005-02-11 devnull }