new venti library.
diff --git a/src/libventi/client.c b/src/libventi/client.c
new file mode 100644
index 0000000..c16fe48
--- /dev/null
+++ b/src/libventi/client.c
@@ -0,0 +1,151 @@
+#include <u.h>
+#include <libc.h>
+#include <venti.h>
+
+static int
+vtfcallrpc(VtConn *z, VtFcall *ou, VtFcall *in)
+{
+ Packet *p;
+
+ p = vtfcallpack(ou);
+ if(p == nil)
+ return -1;
+ if((p = vtrpc(z, p)) == nil)
+ return -1;
+ if(vtfcallunpack(in, p) < 0){
+ packetfree(p);
+ return -1;
+ }
+ if(in->type == VtRerror){
+ werrstr(in->error);
+ vtfcallclear(in);
+ packetfree(p);
+ return -1;
+ }
+ if(in->type != ou->type+1){
+ werrstr("type mismatch: sent %c%d got %c%d",
+ "TR"[ou->type&1], ou->type>>1,
+ "TR"[in->type&1], in->type>>1);
+ vtfcallclear(in);
+ packetfree(p);
+ return -1;
+ }
+ packetfree(p);
+ return 0;
+}
+
+int
+vthello(VtConn *z)
+{
+ VtFcall tx, rx;
+
+ memset(&tx, 0, sizeof tx);
+ tx.type = VtThello;
+ tx.version = z->version;
+ tx.uid = z->uid;
+ if(tx.uid == nil)
+ tx.uid = "anonymous";
+ if(vtfcallrpc(z, &tx, &rx) < 0)
+ return -1;
+ z->sid = rx.sid;
+ rx.sid = 0;
+ vtfcallclear(&rx);
+ return 0;
+}
+
+Packet*
+vtreadpacket(VtConn *z, uchar score[VtScoreSize], uint type, int n)
+{
+ VtFcall tx, rx;
+
+ memset(&tx, 0, sizeof tx);
+ tx.type = VtTread;
+ tx.dtype = type;
+ tx.count = n;
+ memmove(tx.score, score, VtScoreSize);
+ if(vtfcallrpc(z, &tx, &rx) < 0)
+ return nil;
+ if(packetsize(rx.data) > n){
+ werrstr("read returned too much data");
+ packetfree(rx.data);
+ return nil;
+ }
+ packetsha1(rx.data, tx.score);
+ if(memcmp(score, tx.score, VtScoreSize) != 0){
+ werrstr("read asked for %V got %V", score, tx.score);
+ packetfree(rx.data);
+ return nil;
+ }
+
+ return rx.data;
+}
+
+int
+vtread(VtConn *z, uchar score[VtScoreSize], uint type, uchar *buf, int n)
+{
+ int nn;
+ Packet *p;
+
+ if((p = vtreadpacket(z, score, type, n)) == nil)
+ return -1;
+ nn = packetsize(p);
+ if(packetconsume(p, buf, nn) < 0)
+ abort();
+ return nn;
+}
+
+int
+vtwritepacket(VtConn *z, uchar score[VtScoreSize], uint type, Packet *p)
+{
+ VtFcall tx, rx;
+
+ tx.type = VtTwrite;
+ tx.dtype = type;
+ tx.data = p;
+ packetsha1(p, score);
+ if(vtfcallrpc(z, &tx, &rx) < 0)
+ return -1;
+ if(memcmp(score, rx.score, VtScoreSize) != 0){
+ werrstr("sha1 hash mismatch: want %V got %V", score, rx.score);
+ return -1;
+ }
+ return 0;
+}
+
+int
+vtwrite(VtConn *z, uchar score[VtScoreSize], uint type, uchar *buf, int n)
+{
+ Packet *p;
+
+ p = packetforeign(buf, n, nil, nil);
+ return vtwritepacket(z, score, type, p);
+}
+
+int
+vtsync(VtConn *z)
+{
+ VtFcall tx, rx;
+
+ tx.type = VtTsync;
+ return vtfcallrpc(z, &tx, &rx);
+}
+
+int
+vtping(VtConn *z)
+{
+ VtFcall tx, rx;
+
+ tx.type = VtTping;
+ return vtfcallrpc(z, &tx, &rx);
+}
+
+int
+vtconnect(VtConn *z)
+{
+ if(vtversion(z) < 0)
+ return -1;
+ if(vthello(z) < 0)
+ return -1;
+ return 0;
+}
+
