1 #include	<u.h>
2 #include	<libc.h>
3 #include	<fcall.h>
4 
5 int
6 statcheck(uchar *buf, uint nbuf)
7 {
8 	uchar *ebuf;
9 	int i, nstr;
10 
11 	ebuf = buf + nbuf;
12 
13 	if(nbuf < STATFIXLEN || nbuf != BIT16SZ + GBIT16(buf))
14 		return -1;
15 
16 	buf += STATFIXLEN - 4 * BIT16SZ;
17 
18 	nstr = 4;
19 	for(i = 0; i < nstr; i++){
20 		if(buf + BIT16SZ > ebuf)
21 			return -1;
22 		buf += BIT16SZ + GBIT16(buf);
23 	}
24 
25 	if(buf != ebuf)
26 		return -1;
27 
28 	return 0;
29 }
30 
31 static char nullstring[] = "";
32 
33 uint
34 convM2D(uchar *buf, uint nbuf, Dir *d, char *strs)
35 {
36 	uchar *p, *ebuf;
37 	char *sv[5];
38 	int i, ns, nstr;
39 
40 	if(nbuf < STATFIXLEN)
41 		return 0;
42 
43 	p = buf;
44 	ebuf = buf + nbuf;
45 
46 	p += BIT16SZ;	/* ignore size */
47 	d->type = GBIT16(p);
48 	p += BIT16SZ;
49 	d->dev = GBIT32(p);
50 	p += BIT32SZ;
51 	d->qid.type = GBIT8(p);
52 	p += BIT8SZ;
53 	d->qid.vers = GBIT32(p);
54 	p += BIT32SZ;
55 	d->qid.path = GBIT64(p);
56 	p += BIT64SZ;
57 	d->mode = GBIT32(p);
58 	p += BIT32SZ;
59 	d->atime = GBIT32(p);
60 	p += BIT32SZ;
61 	d->mtime = GBIT32(p);
62 	p += BIT32SZ;
63 	d->length = GBIT64(p);
64 	p += BIT64SZ;
65 
66 	nstr = 4;
67 	for(i = 0; i < nstr; i++){
68 		if(p + BIT16SZ > ebuf)
69 			return 0;
70 		ns = GBIT16(p);
71 		p += BIT16SZ;
72 		if(p + ns > ebuf)
73 			return 0;
74 		if(strs){
75 			sv[i] = strs;
76 			memmove(strs, p, ns);
77 			strs += ns;
78 			*strs++ = '\0';
79 		}
80 		p += ns;
81 	}
82 
83 	if(strs){
84 		d->name = sv[0];
85 		d->uid = sv[1];
86 		d->gid = sv[2];
87 		d->muid = sv[3];
88 		d->ext = nullstring;
89 	}else{
90 		d->name = nullstring;
91 		d->uid = nullstring;
92 		d->gid = nullstring;
93 		d->muid = nullstring;
94 		d->ext = nullstring;
95 	}
96 
97 	return p - buf;
98 }