ref: c3ba64f6935322f09b6de5c2285544fd471c605d
dir: /sys/src/cmd/execnet/client.c/
#include <u.h>
#include <libc.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include "dat.h"
int nclient;
Client **client;
#define Zmsg ((Msg*)~0)
char nocmd[] = "";
static void readthread(void*);
static void writethread(void*);
static void kickwriter(Client*);
int
newclient(void)
{
int i;
Client *c;
for(i=0; i<nclient; i++)
if(client[i]->ref==0 && !client[i]->moribund)
return i;
c = emalloc(sizeof(Client));
c->writerkick = chancreate(sizeof(void*), 1);
c->execpid = chancreate(sizeof(ulong), 0);
c->cmd = nocmd;
c->readerproc = ioproc();
c->writerproc = ioproc();
c->num = nclient;
if(nclient%16 == 0)
client = erealloc(client, (nclient+16)*sizeof(client[0]));
client[nclient++] = c;
return nclient-1;
}
void
die(Client *c)
{
Msg *m, *next;
Req *r, *rnext;
c->moribund = 1;
kickwriter(c);
iointerrupt(c->readerproc);
iointerrupt(c->writerproc);
if(--c->activethread == 0){
if(c->cmd != nocmd){
free(c->cmd);
c->cmd = nocmd;
}
c->pid = 0;
c->moribund = 0;
c->status = Closed;
for(m=c->mq; m && m != Zmsg; m=next){
next = m->link;
free(m);
}
c->mq = nil;
if(c->rq != nil){
for(r=c->rq; r; r=rnext){
rnext = r->aux;
respond(r, "hangup");
}
c->rq = nil;
}
if(c->wq != nil){
for(r=c->wq; r; r=rnext){
rnext = r->aux;
respond(r, "hangup");
}
c->wq = nil;
}
c->rq = nil;
c->wq = nil;
c->emq = nil;
c->erq = nil;
c->ewq = nil;
}
}
void
closeclient(Client *c)
{
if(--c->ref == 0){
if(c->pid > 0)
postnote(PNPROC, c->pid, "kill");
c->status = Hangup;
close(c->fd[0]);
c->fd[0] = c->fd[1] = -1;
c->moribund = 1;
kickwriter(c);
iointerrupt(c->readerproc);
iointerrupt(c->writerproc);
c->activethread++;
die(c);
}
}
void
queuerdreq(Client *c, Req *r)
{
if(c->rq==nil)
c->erq = &c->rq;
*c->erq = r;
r->aux = nil;
c->erq = (Req**)&r->aux;
}
void
queuewrreq(Client *c, Req *r)
{
if(c->wq==nil)
c->ewq = &c->wq;
*c->ewq = r;
r->aux = nil;
c->ewq = (Req**)&r->aux;
}
void
queuemsg(Client *c, Msg *m)
{
if(c->mq==nil)
c->emq = &c->mq;
*c->emq = m;
if(m != Zmsg){
m->link = nil;
c->emq = (Msg**)&m->link;
}else
c->emq = nil;
}
void
matchmsgs(Client *c)
{
Req *r;
Msg *m;
int n, rm;
while(c->rq && c->mq){
r = c->rq;
c->rq = r->aux;
rm = 0;
m = c->mq;
if(m == Zmsg){
respond(r, "execnet: no more data");
break;
}
n = r->ifcall.count;
if(n >= m->ep - m->rp){
n = m->ep - m->rp;
c->mq = m->link;
rm = 1;
}
if(n)
memmove(r->ofcall.data, m->rp, n);
if(rm)
free(m);
else
m->rp += n;
r->ofcall.count = n;
respond(r, nil);
}
}
void
findrdreq(Client *c, Req *r)
{
Req **l;
for(l=&c->rq; *l; l=(Req**)&(*l)->aux){
if(*l == r){
*l = r->aux;
if(*l == nil)
c->erq = l;
respond(r, "interrupted");
break;
}
}
}
void
findwrreq(Client *c, Req *r)
{
Req **l;
for(l=&c->wq; *l; l=(Req**)&(*l)->aux){
if(*l == r){
*l = r->aux;
if(*l == nil)
c->ewq = l;
respond(r, "interrupted");
return;
}
}
}
void
dataread(Req *r, Client *c)
{
queuerdreq(c, r);
matchmsgs(c);
}
static void
readthread(void *a)
{
uchar *buf;
int n;
Client *c;
Ioproc *io;
Msg *m;
c = a;
threadsetname("read%d", c->num);
buf = emalloc(8192);
io = c->readerproc;
while((n = ioread(io, c->fd[0], buf, 8192)) >= 0){
m = emalloc(sizeof(Msg)+n);
m->rp = (uchar*)&m[1];
m->ep = m->rp + n;
if(n)
memmove(m->rp, buf, n);
queuemsg(c, m);
matchmsgs(c);
}
queuemsg(c, Zmsg);
free(buf);
die(c);
}
static void
kickwriter(Client *c)
{
nbsendp(c->writerkick, nil);
}
void
clientflush(Req *or, Client *c)
{
if(or->ifcall.type == Tread)
findrdreq(c, or);
else{
if(c->execreq == or){
c->execreq = nil;
iointerrupt(c->writerproc);
ioflush(c->writerproc);
}
findwrreq(c, or);
if(c->curw == or){
c->curw = nil;
iointerrupt(c->writerproc);
kickwriter(c);
}
}
}
void
datawrite(Req *r, Client *c)
{
queuewrreq(c, r);
kickwriter(c);
}
static void
writethread(void *a)
{
char e[ERRMAX];
uchar *buf;
int n;
Ioproc *io;
Req *r;
Client *c;
c = a;
threadsetname("write%d", c->num);
buf = emalloc(8192);
io = c->writerproc;
for(;;){
while(c->wq == nil){
if(c->moribund)
goto Out;
recvp(c->writerkick);
if(c->moribund)
goto Out;
}
r = c->wq;
c->wq = r->aux;
c->curw = r;
n = iowrite(io, c->fd[1], r->ifcall.data, r->ifcall.count);
c->curw = nil;
if(chatty9p)
fprint(2, "io->write returns %d\n", n);
if(n >= 0){
r->ofcall.count = n;
respond(r, nil);
}else{
rerrstr(e, sizeof e);
respond(r, e);
}
}
Out:
free(buf);
die(c);
}
static void
execproc(void *a)
{
int i, fd;
Client *c;
c = a;
threadsetname("execproc%d", c->num);
if(pipe(c->fd) < 0){
rerrstr(c->err, sizeof c->err);
sendul(c->execpid, -1);
return;
}
rfork(RFFDG);
fd = c->fd[1];
close(c->fd[0]);
dup(fd, 0);
dup(fd, 1);
for(i=3; i<100; i++) /* should do better */
close(i);
strcpy(c->err, "exec failed");
procexecl(c->execpid, "/bin/rc", "rc", "-c", c->cmd, nil);
}
static void
execthread(void *a)
{
Client *c;
int p;
c = a;
threadsetname("exec%d", c->num);
c->execpid = chancreate(sizeof(ulong), 0);
proccreate(execproc, c, STACK);
p = recvul(c->execpid);
chanfree(c->execpid);
c->execpid = nil;
close(c->fd[1]);
c->fd[1] = c->fd[0];
if(p != -1){
c->pid = p;
c->activethread = 2;
threadcreate(readthread, c, STACK);
threadcreate(writethread, c, STACK);
if(c->execreq)
respond(c->execreq, nil);
}else{
if(c->execreq)
respond(c->execreq, c->err);
}
}
void
ctlwrite(Req *r, Client *c)
{
char *f[3], *s, *p;
int nf;
s = emalloc(r->ifcall.count+1);
memmove(s, r->ifcall.data, r->ifcall.count);
s[r->ifcall.count] = '\0';
f[0] = s;
p = strchr(s, ' ');
if(p == nil)
nf = 1;
else{
*p++ = '\0';
f[1] = p;
nf = 2;
}
if(f[0][0] == '\0'){
free(s);
respond(r, nil);
return;
}
r->ofcall.count = r->ifcall.count;
if(strcmp(f[0], "hangup") == 0){
if(c->pid == 0){
respond(r, "connection already hung up");
goto Out;
}
postnote(PNPROC, c->pid, "kill");
respond(r, nil);
goto Out;
}
if(strcmp(f[0], "connect") == 0){
if(c->cmd != nocmd){
respond(r, "already have connection");
goto Out;
}
if(nf == 1){
respond(r, "need argument to connect");
goto Out;
}
c->status = Exec;
if(p = strrchr(f[1], '!'))
*p = '\0';
c->cmd = emalloc(4+1+strlen(f[1])+1);
strcpy(c->cmd, "exec ");
strcat(c->cmd, f[1]);
c->execreq = r;
threadcreate(execthread, c, STACK);
goto Out;
}
respond(r, "bad or inappropriate control message");
Out:
free(s);
}