/*
* Determine the variables being used and clear non-used onces.
*/
void
MSresetVariables(Client cntxt, MalBlkPtr mb, MalStkPtr glb, int start)
{
int i;
bit *used = GDKzalloc(mb->vtop * sizeof(bit));
if( used == NULL){
GDKerror("MSresetVariables" MAL_MALLOC_FAIL);
return;
}
for (i = 0; i < start && start < mb->vtop; i++)
used[i] = 1;
if (mb->errors == 0)
for (i = start; i < mb->vtop; i++) {
if (used[i] || !isTmpVar(mb, i)) {
assert(!mb->var[i]->value.vtype || isVarConstant(mb, i));
used[i] = 1;
}
if (glb && !used[i]) {
if (isVarConstant(mb, i))
garbageElement(cntxt, &glb->stk[i]);
/* clean stack entry */
glb->stk[i].vtype = TYPE_int;
glb->stk[i].len = 0;
glb->stk[i].val.pval = 0;
}
}
if (mb->errors == 0)
trimMalVariables_(mb, used, glb);
GDKfree(used);
}
/*
* Execution of the SQL program is delegated to the MALengine.
* Different cases should be distinguished. The default is to
* hand over the MAL block derived by the parser for execution.
* However, when we received an Execute call, we make a shortcut
* and prepare the stack for immediate execution
*/
str
SQLexecutePrepared(Client c, backend *be, cq *q)
{
mvc *m = be->mvc;
int argc, parc;
ValPtr *argv, argvbuffer[MAXARG], v;
ValRecord *argrec, argrecbuffer[MAXARG];
MalBlkPtr mb;
MalStkPtr glb;
InstrPtr pci;
int i;
str ret;
Symbol qcode = q->code;
if (!qcode || qcode->def->errors) {
if (!qcode && *m->errstr)
return createException(PARSE, "SQLparser", "%s", m->errstr);
throw(SQL, "SQLengine", "39000!program contains errors");
}
mb = qcode->def;
pci = getInstrPtr(mb, 0);
if (pci->argc >= MAXARG)
argv = (ValPtr *) GDKmalloc(sizeof(ValPtr) * pci->argc);
else
argv = argvbuffer;
if (pci->retc >= MAXARG)
argrec = (ValRecord *) GDKmalloc(sizeof(ValRecord) * pci->retc);
else
argrec = argrecbuffer;
/* prepare the target variables */
for (i = 0; i < pci->retc; i++) {
argv[i] = argrec + i;
argv[i]->vtype = getVarGDKType(mb, i);
}
argc = m->argc;
parc = q->paramlen;
if (argc != parc) {
if (pci->argc >= MAXARG)
GDKfree(argv);
if (pci->retc >= MAXARG)
GDKfree(argrec);
throw(SQL, "sql.prepare", "07001!EXEC: wrong number of arguments for prepared statement: %d, expected %d", argc, parc);
} else {
for (i = 0; i < m->argc; i++) {
atom *arg = m->args[i];
sql_subtype *pt = q->params + i;
if (!atom_cast(arg, pt)) {
/*sql_error(c, 003, buf); */
if (pci->argc >= MAXARG)
GDKfree(argv);
if (pci->retc >= MAXARG)
GDKfree(argrec);
throw(SQL, "sql.prepare", "07001!EXEC: wrong type for argument %d of " "prepared statement: %s, expected %s", i + 1, atom_type(arg)->type->sqlname, pt->type->sqlname);
}
argv[pci->retc + i] = &arg->data;
}
}
glb = (MalStkPtr) (q->stk);
ret = callMAL(c, mb, &glb, argv, (m->emod & mod_debug ? 'n' : 0));
/* cleanup the arguments */
for (i = pci->retc; i < pci->argc; i++) {
garbageElement(c, v = &glb->stk[pci->argv[i]]);
v->vtype = TYPE_int;
v->val.ival = int_nil;
}
if (glb && ret) /* error */
garbageCollector(c, mb, glb, glb != 0);
q->stk = (backend_stack) glb;
if (glb && SQLdebug & 1)
printStack(GDKstdout, mb, glb);
if (pci->argc >= MAXARG)
GDKfree(argv);
if (pci->retc >= MAXARG)
GDKfree(argrec);
return ret;
}
