ref: fe594760ebddac23e673d189d2152062ef75d8b8
dir: /sys/src/libsunrpc/client.c/
/*
* Sun RPC client.
*/
#include <u.h>
#include <libc.h>
#include <thread.h>
#include <sunrpc.h>
typedef struct Out Out;
struct Out
{
char err[ERRMAX]; /* error string */
Channel *creply; /* send to finish rpc */
uchar *p; /* pending request packet */
int n; /* size of request */
ulong tag; /* flush tag of pending request */
ulong xid; /* xid of pending request */
ulong st; /* first send time */
ulong t; /* resend time */
int nresend; /* number of resends */
SunRpc rpc; /* response rpc */
};
static void
udpThread(void *v)
{
uchar *p, *buf;
Ioproc *io;
int n;
SunClient *cli;
enum { BufSize = 65536 };
cli = v;
buf = emalloc(BufSize);
io = ioproc();
p = nil;
for(;;){
n = ioread(io, cli->fd, buf, BufSize);
if(n <= 0)
break;
p = emalloc(4+n);
memmove(p+4, buf, n);
p[0] = n>>24;
p[1] = n>>16;
p[2] = n>>8;
p[3] = n;
if(sendp(cli->readchan, p) == 0)
break;
p = nil;
}
free(p);
closeioproc(io);
while(send(cli->dying, nil) == -1)
;
}
static void
netThread(void *v)
{
uchar *p, buf[4];
Ioproc *io;
uint n, tot;
int done;
SunClient *cli;
cli = v;
io = ioproc();
tot = 0;
p = nil;
for(;;){
n = ioreadn(io, cli->fd, buf, 4);
if(n != 4)
break;
n = (buf[0]<<24)|(buf[1]<<16)|(buf[2]<<8)|buf[3];
if(cli->chatty)
fprint(2, "%.8ux...", n);
done = n&0x80000000;
n &= ~0x80000000;
if(tot == 0){
p = emalloc(4+n);
tot = 4;
}else
p = erealloc(p, tot+n);
if(ioreadn(io, cli->fd, p+tot, n) != n)
break;
tot += n;
if(done){
p[0] = tot>>24;
p[1] = tot>>16;
p[2] = tot>>8;
p[3] = tot;
if(sendp(cli->readchan, p) == 0)
break;
p = nil;
tot = 0;
}
}
free(p);
closeioproc(io);
while(send(cli->dying, 0) == -1)
;
}
static void
timerThread(void *v)
{
Ioproc *io;
SunClient *cli;
cli = v;
io = ioproc();
for(;;){
if(iosleep(io, 200) < 0)
break;
if(sendul(cli->timerchan, 0) == 0)
break;
}
closeioproc(io);
while(send(cli->dying, 0) == -1)
;
}
static ulong
msec(void)
{
return nsec()/1000000;
}
static ulong
twait(ulong rtt, int nresend)
{
ulong t;
t = rtt;
if(nresend <= 1)
{}
else if(nresend <= 3)
t *= 2;
else if(nresend <= 18)
t <<= nresend-2;
else
t = 60*1000;
if(t > 60*1000)
t = 60*1000;
return t;
}
static void
rpcMuxThread(void *v)
{
uchar *buf, *p, *ep;
int i, n, nout, mout;
ulong t, xidgen, tag;
Alt a[5];
Out *o, **out;
SunRpc rpc;
SunClient *cli;
cli = v;
mout = 16;
nout = 0;
out = emalloc(mout*sizeof(out[0]));
xidgen = truerand();
a[0].op = CHANRCV;
a[0].c = cli->rpcchan;
a[0].v = &o;
a[1].op = CHANNOP;
a[1].c = cli->timerchan;
a[1].v = nil;
a[2].op = CHANRCV;
a[2].c = cli->flushchan;
a[2].v = &tag;
a[3].op = CHANRCV;
a[3].c = cli->readchan;
a[3].v = &buf;
a[4].op = CHANEND;
for(;;){
switch(alt(a)){
case 0: /* o = <-rpcchan */
if(o == nil)
goto Done;
cli->nsend++;
/* set xid */
o->xid = ++xidgen;
if(cli->needcount)
p = o->p+4;
else
p = o->p;
p[0] = xidgen>>24;
p[1] = xidgen>>16;
p[2] = xidgen>>8;
p[3] = xidgen;
if(write(cli->fd, o->p, o->n) != o->n){
free(o->p);
o->p = nil;
snprint(o->err, sizeof o->err, "write: %r");
sendp(o->creply, 0);
break;
}
if(nout >= mout){
mout *= 2;
out = erealloc(out, mout*sizeof(out[0]));
}
o->st = msec();
o->nresend = 0;
o->t = o->st + twait(cli->rtt.avg, 0);
if(cli->chatty) fprint(2, "send %lux %lud %lud\n", o->xid, o->st, o->t);
out[nout++] = o;
a[1].op = CHANRCV;
break;
case 1: /* <-timerchan */
t = msec();
for(i=0; i<nout; i++){
o = out[i];
if((int)(t - o->t) > 0){
if(cli->chatty) fprint(2, "resend %lux %lud %lud\n", o->xid, t, o->t);
if(cli->maxwait && t - o->st >= cli->maxwait){
free(o->p);
o->p = nil;
strcpy(o->err, "timeout");
sendp(o->creply, 0);
out[i--] = out[--nout];
continue;
}
cli->nresend++;
o->nresend++;
o->t = t + twait(cli->rtt.avg, o->nresend);
if(write(cli->fd, o->p, o->n) != o->n){
free(o->p);
o->p = nil;
snprint(o->err, sizeof o->err, "rewrite: %r");
sendp(o->creply, 0);
out[i--] = out[--nout];
continue;
}
}
}
/* stop ticking if no work; rpcchan will turn it back on */
if(nout == 0)
a[1].op = CHANNOP;
break;
case 2: /* tag = <-flushchan */
for(i=0; i<nout; i++){
o = out[i];
if(o->tag == tag){
out[i--] = out[--nout];
strcpy(o->err, "flushed");
free(o->p);
o->p = nil;
sendp(o->creply, 0);
}
}
break;
case 3: /* buf = <-readchan */
p = buf;
n = (p[0]<<24)|(p[1]<<16)|(p[2]<<8)|p[3];
p += 4;
ep = p+n;
if(sunRpcUnpack(p, ep, &p, &rpc) < 0){
fprint(2, "in: %.*H unpack failed\n", n, buf+4);
free(buf);
break;
}
if(cli->chatty)
fprint(2, "in: %B\n", &rpc);
if(rpc.iscall){
fprint(2, "did not get reply\n");
free(buf);
break;
}
o = nil;
for(i=0; i<nout; i++){
o = out[i];
if(o->xid == rpc.xid)
break;
}
if(i==nout){
if(cli->chatty) fprint(2, "did not find waiting request\n");
free(buf);
break;
}
out[i] = out[--nout];
free(o->p);
o->p = nil;
if(rpc.status == SunSuccess){
o->p = buf;
o->rpc = rpc;
}else{
o->p = nil;
free(buf);
sunErrstr(rpc.status);
rerrstr(o->err, sizeof o->err);
}
sendp(o->creply, 0);
break;
}
}
Done:
free(out);
sendp(cli->dying, 0);
}
SunClient*
sunDial(char *address)
{
int fd;
SunClient *cli;
if((fd = dial(address, 0, 0, 0)) < 0)
return nil;
cli = emalloc(sizeof(SunClient));
cli->fd = fd;
cli->maxwait = 15000;
cli->rtt.avg = 1000;
cli->dying = chancreate(sizeof(void*), 0);
cli->rpcchan = chancreate(sizeof(Out*), 0);
cli->timerchan = chancreate(sizeof(ulong), 0);
cli->flushchan = chancreate(sizeof(ulong), 0);
cli->readchan = chancreate(sizeof(uchar*), 0);
if(strstr(address, "udp!")){
cli->needcount = 0;
cli->nettid = threadcreate(udpThread, cli, SunStackSize);
cli->timertid = threadcreate(timerThread, cli, SunStackSize);
}else{
cli->needcount = 1;
cli->nettid = threadcreate(netThread, cli, SunStackSize);
/* assume reliable: don't need timer */
/* BUG: netThread should know how to redial */
}
threadcreate(rpcMuxThread, cli, SunStackSize);
return cli;
}
void
sunClientClose(SunClient *cli)
{
int n;
/*
* Threadints get you out of any stuck system calls
* or thread rendezvouses, but do nothing if the thread
* is in the ready state. Keep interrupting until it takes.
*/
n = 0;
if(!cli->timertid)
n++;
while(n < 2){
threadint(cli->nettid);
if(cli->timertid)
threadint(cli->timertid);
yield();
while(nbrecv(cli->dying, nil) == 1)
n++;
}
sendp(cli->rpcchan, 0);
recvp(cli->dying);
/* everyone's gone: clean up */
close(cli->fd);
chanfree(cli->flushchan);
chanfree(cli->readchan);
chanfree(cli->timerchan);
free(cli);
}
void
sunClientFlushRpc(SunClient *cli, ulong tag)
{
sendul(cli->flushchan, tag);
}
void
sunClientProg(SunClient *cli, SunProg *p)
{
if(cli->nprog%16 == 0)
cli->prog = erealloc(cli->prog, (cli->nprog+16)*sizeof(cli->prog[0]));
cli->prog[cli->nprog++] = p;
}
int
sunClientRpc(SunClient *cli, ulong tag, SunCall *tx, SunCall *rx, uchar **tofree)
{
uchar *bp, *p, *ep;
int i, n1, n2, n, nn;
Out o;
SunProg *prog;
SunStatus ok;
for(i=0; i<cli->nprog; i++)
if(cli->prog[i]->prog == tx->rpc.prog && cli->prog[i]->vers == tx->rpc.vers)
break;
if(i==cli->nprog){
werrstr("unknown sun rpc program %d version %d", tx->rpc.prog, tx->rpc.vers);
return -1;
}
prog = cli->prog[i];
if(cli->chatty){
fprint(2, "out: %B\n", &tx->rpc);
fprint(2, "\t%C\n", tx);
}
n1 = sunRpcSize(&tx->rpc);
n2 = sunCallSize(prog, tx);
n = n1+n2;
if(cli->needcount)
n += 4;
bp = emalloc(n);
ep = bp+n;
p = bp;
if(cli->needcount){
nn = n-4;
p[0] = (nn>>24)|0x80;
p[1] = nn>>16;
p[2] = nn>>8;
p[3] = nn;
p += 4;
}
if((ok = sunRpcPack(p, ep, &p, &tx->rpc)) != SunSuccess
|| (ok = sunCallPack(prog, p, ep, &p, tx)) != SunSuccess){
sunErrstr(ok);
free(bp);
return -1;
}
if(p != ep){
werrstr("rpc: packet size mismatch");
free(bp);
return -1;
}
memset(&o, 0, sizeof o);
o.creply = chancreate(sizeof(void*), 0);
o.tag = tag;
o.p = bp;
o.n = n;
sendp(cli->rpcchan, &o);
recvp(o.creply);
chanfree(o.creply);
if(o.p == nil){
werrstr("%s", o.err);
return -1;
}
p = o.rpc.data;
ep = p+o.rpc.ndata;
rx->rpc = o.rpc;
rx->rpc.proc = tx->rpc.proc;
rx->rpc.prog = tx->rpc.prog;
rx->rpc.vers = tx->rpc.vers;
rx->type = (rx->rpc.proc<<1)|1;
if((ok = sunCallUnpack(prog, p, ep, &p, rx)) != SunSuccess){
sunErrstr(ok);
werrstr("unpack: %r");
free(o.p);
return -1;
}
if(cli->chatty){
fprint(2, "in: %B\n", &rx->rpc);
fprint(2, "in:\t%C\n", rx);
}
if(tofree)
*tofree = o.p;
else
free(o.p);
return 0;
}