1 #include	"lib9.h"
2 #include	<bio.h>
3 
4 long
5 Bread(Biobuf *bp, void *ap, long count)
6 {
7 	long c;
8 	unsigned char *p;
9 	int i, n, ic;
10 
11 	p = ap;
12 	c = count;
13 	ic = bp->icount;
14 
15 	while(c > 0) {
16 		n = -ic;
17 		if(n > c)
18 			n = c;
19 		if(n == 0) {
20 			if(bp->state != Bractive)
21 				break;
22 			i = read(bp->fid, bp->bbuf, bp->bsize);
23 			if(i <= 0) {
24 				bp->state = Bracteof;
25 				if(i < 0)
26 					bp->state = Binactive;
27 				break;
28 			}
29 			bp->gbuf = bp->bbuf;
30 			bp->offset += i;
31 			if(i < bp->bsize) {
32 				memmove(bp->ebuf-i, bp->bbuf, i);
33 				bp->gbuf = bp->ebuf-i;
34 			}
35 			ic = -i;
36 			continue;
37 		}
38 		memmove(p, bp->ebuf+ic, n);
39 		c -= n;
40 		ic += n;
41 		p += n;
42 	}
43 	bp->icount = ic;
44 	return count-c;
45 }