/*
* When a client needs to be terminated then the file descriptors for
* its input/output are simply closed. This leads to a graceful
* degradation, but may take some time when the client is busy. A more
* forcefull method is to kill the client thread, but this may leave
* locks and semaphores in an undesirable state.
*
* The routine freeClient ends a single client session, but through side
* effects of sharing IO descriptors, also its children. Conversely, a
* child can not close a parent.
*/
void
MCfreeClient(Client c)
{
c->mode = FINISHCLIENT;
#ifdef MAL_CLIENT_DEBUG
fprintf(stderr,"# Free client %d\n", c->idx);
#endif
MCexitClient(c);
/* scope list and curprg can not be removed, because the client may
* reside in a quit() command. Therefore the scopelist is re-used.
*/
c->scenario = NULL;
if (c->prompt)
GDKfree(c->prompt);
c->prompt = NULL;
c->promptlength = -1;
if (c->errbuf) {
/* no client threads in embedded mode */
#ifndef HAVE_EMBEDDED
GDKsetbuf(0);
#endif
if (c->father == NULL)
GDKfree(c->errbuf);
c->errbuf = 0;
}
if (c->usermodule)
freeModule(c->usermodule);
c->usermodule = c->curmodule = 0;
c->father = 0;
c->login = c->lastcmd = 0;
//c->active = 0;
c->qtimeout = 0;
c->stimeout = 0;
c->user = oid_nil;
if( c->username){
GDKfree(c->username);
c->username = 0;
}
c->mythread = 0;
if (c->glb) {
freeStack(c->glb);
c->glb = NULL;
}
if( c->error_row){
BBPrelease(c->error_row->batCacheid);
BBPrelease(c->error_fld->batCacheid);
BBPrelease(c->error_msg->batCacheid);
BBPrelease(c->error_input->batCacheid);
c->error_row = c->error_fld = c->error_msg = c->error_input = NULL;
}
if( c->wlc)
freeMalBlk(c->wlc);
c->wlc_kind = 0;
c->wlc = NULL;
MT_sema_destroy(&c->s);
c->mode = MCshutdowninprogress()? BLOCKCLIENT: FREECLIENT;
}
/*
* Every client has a 'main' function to collect the statements. Once
* the END instruction has been found, it is added to the symbol table
* and a fresh container is being constructed. Note, this scheme makes
* testing for recursive function calls a little more difficult.
* Therefore, type checking should be performed afterwards.
*
* In interactive mode, the closing statement is never reached. The
* 'main' procedure is typically cleaned between successive external
* messages except for its variables, which are considerd global. This
* storage container is re-used when during the previous call nothing
* was added. At the end of the session we have to garbage collect the
* BATs introduced.
*/
static void
MSresetClientPrg(Client cntxt)
{
MalBlkPtr mb;
InstrPtr p;
cntxt->itrace = 0; /* turn off any debugging */
mb = cntxt->curprg->def;
mb->typefixed = 0;
mb->flowfixed = 0;
mb->stop = 1;
mb->errors = 0;
p = mb->stmt[0];
p->gc = 0;
p->retc = 1;
p->argc = 1;
/* remove any MAL history */
if (mb->history) {
freeMalBlk(mb->history);
mb->history = 0;
}
}
/*
* This is a phtread started function. Here we start the client. We
* need to initialize and allocate space for the global variables.
* Thereafter it is up to the scenario interpreter to process input.
*/
void
MSserveClient(void *dummy)
{
MalBlkPtr mb;
Client c = (Client) dummy;
str msg = 0;
if (!isAdministrator(c) && MCinitClientThread(c) < 0) {
MCcloseClient(c);
return;
}
/*
* A stack frame is initialized to keep track of global variables.
* The scenarios are run until we finally close the last one.
*/
mb = c->curprg->def;
if (c->glb == NULL)
c->glb = newGlobalStack(MAXGLOBALS + mb->vsize);
if (c->glb == NULL) {
showException(c->fdout, MAL, "serveClient", MAL_MALLOC_FAIL);
c->mode = FINISHCLIENT + 1; /* == RUNCLIENT */
} else {
c->glb->stktop = mb->vtop;
c->glb->blk = mb;
}
if (c->scenario == 0)
msg = defaultScenario(c);
if (msg) {
showException(c->fdout, MAL, "serveClient", "could not initialize default scenario");
c->mode = FINISHCLIENT + 1; /* == RUNCLIENT */
GDKfree(msg);
} else {
do {
do {
runScenario(c);
if (c->mode == FINISHCLIENT)
break;
resetScenario(c);
} while (c->scenario && !GDKexiting());
} while (c->scenario && c->mode != FINISHCLIENT && !GDKexiting());
}
/* pre announce our exiting: cleaning up may take a while and we
* don't want to get killed during that time for fear of
* deadlocks */
MT_exiting_thread();
/*
* At this stage we should clean out the MAL block
*/
freeMalBlk(c->curprg->def);
c->curprg->def = 0;
if (c->mode > FINISHCLIENT) {
if (isAdministrator(c) /* && moreClients(0)==0 */) {
if (c->scenario) {
exitScenario(c);
}
}
}
if (!isAdministrator(c))
MCcloseClient(c);
}
