1 #include <u.h>
2 #include <libc.h>
3 #include <venti.h>
4 
5 static int
6 vtfcallrpc(VtConn *z, VtFcall *ou, VtFcall *in)
7 {
8 	Packet *p;
9 
10 	p = vtfcallpack(ou);
11 	if(p == nil)
12 		return -1;
13 	if((p = vtrpc(z, p)) == nil)
14 		return -1;
15 	if(vtfcallunpack(in, p) < 0){
16 		packetfree(p);
17 		return -1;
18 	}
19 	if(in->type == VtRerror){
20 		werrstr(in->error);
21 		vtfcallclear(in);
22 		packetfree(p);
23 		return -1;
24 	}
25 	if(in->type != ou->type+1){
26 		werrstr("type mismatch: sent %c%d got %c%d",
27 			"TR"[ou->type&1], ou->type>>1,
28 			"TR"[in->type&1], in->type>>1);
29 		vtfcallclear(in);
30 		packetfree(p);
31 		return -1;
32 	}
33 	packetfree(p);
34 	return 0;
35 }
36 
37 int
38 vthello(VtConn *z)
39 {
40 	VtFcall tx, rx;
41 
42 	memset(&tx, 0, sizeof tx);
43 	tx.type = VtThello;
44 	tx.version = z->version;
45 	tx.uid = z->uid;
46 	if(tx.uid == nil)
47 		tx.uid = "anonymous";
48 	if(vtfcallrpc(z, &tx, &rx) < 0)
49 		return -1;
50 	z->sid = rx.sid;
51 	rx.sid = 0;
52 	vtfcallclear(&rx);
53 	return 0;
54 }
55 
56 Packet*
57 vtreadpacket(VtConn *z, uchar score[VtScoreSize], uint type, int n)
58 {
59 	VtFcall tx, rx;
60 
61 	memset(&tx, 0, sizeof tx);
62 	tx.type = VtTread;
63 	tx.dtype = type;
64 	tx.count = n;
65 	memmove(tx.score, score, VtScoreSize);
66 	if(vtfcallrpc(z, &tx, &rx) < 0)
67 		return nil;
68 	if(packetsize(rx.data) > n){
69 		werrstr("read returned too much data");
70 		packetfree(rx.data);
71 		return nil;
72 	}
73 	packetsha1(rx.data, tx.score);
74 	if(memcmp(score, tx.score, VtScoreSize) != 0){
75 		werrstr("read asked for %V got %V", score, tx.score);
76 		packetfree(rx.data);
77 		return nil;
78 	}
79 
80 	return rx.data;
81 }
82 
83 int
84 vtread(VtConn *z, uchar score[VtScoreSize], uint type, uchar *buf, int n)
85 {
86 	int nn;
87 	Packet *p;
88 
89 	if((p = vtreadpacket(z, score, type, n)) == nil)
90 		return -1;
91 	nn = packetsize(p);
92 	if(packetconsume(p, buf, nn) < 0)
93 		abort();
94 	return nn;
95 }
96 
97 int
98 vtwritepacket(VtConn *z, uchar score[VtScoreSize], uint type, Packet *p)
99 {
100 	VtFcall tx, rx;
101 
102 	tx.type = VtTwrite;
103 	tx.dtype = type;
104 	tx.data = p;
105 	packetsha1(p, score);
106 	if(vtfcallrpc(z, &tx, &rx) < 0)
107 		return -1;
108 	if(memcmp(score, rx.score, VtScoreSize) != 0){
109 		werrstr("sha1 hash mismatch: want %V got %V", score, rx.score);
110 		return -1;
111 	}
112 	return 0;
113 }
114 
115 int
116 vtwrite(VtConn *z, uchar score[VtScoreSize], uint type, uchar *buf, int n)
117 {
118 	Packet *p;
119 
120 	p = packetforeign(buf, n, nil, nil);
121 	return vtwritepacket(z, score, type, p);
122 }
123 
124 int
125 vtsync(VtConn *z)
126 {
127 	VtFcall tx, rx;
128 
129 	tx.type = VtTsync;
130 	return vtfcallrpc(z, &tx, &rx);
131 }
132 
133 int
134 vtping(VtConn *z)
135 {
136 	VtFcall tx, rx;
137 
138 	tx.type = VtTping;
139 	return vtfcallrpc(z, &tx, &rx);
140 }
141 
142 int
143 vtconnect(VtConn *z)
144 {
145 	if(vtversion(z) < 0)
146 		return -1;
147 	if(vthello(z) < 0)
148 		return -1;
149 	return 0;
150 }
151