str
runFactory(Client cntxt, MalBlkPtr mb, MalBlkPtr mbcaller, MalStkPtr stk, InstrPtr pci)
{
Plant pl=0;
int firstcall= TRUE, i, k;
InstrPtr psig = getInstrPtr(mb, 0);
ValPtr lhs, rhs;
char cmd;
str msg;
#ifdef DEBUG_MAL_FACTORY
fprintf(stderr, "#factoryMgr called\n");
#endif
/* the lookup can be largely avoided by handing out the index
upon factory definition. todo
Alternative is to move them to the front
*/
for(i=0; i< lastPlant; i++)
if( plants[i].factory == mb){
if(i > 0 && i< lastPlant ){
PlantRecord prec= plants[i-1];
plants[i-1] = plants[i];
plants[i]= prec;
i--;
}
pl= plants+i;
firstcall= FALSE;
break;
}
if (pl == 0) {
/* compress the plant table*/
for(k=i=0;i<=lastPlant; i++)
if( plants[i].inuse)
plants[k++]= plants[i];
lastPlant = k;
/* initialize a new plant using the owner policy */
pl = newPlant(mb);
if (pl == NULL)
throw(MAL, "factory.new", SQLSTATE(HY001) MAL_MALLOC_FAIL);
}
/*
* We have found a factory to process the request.
* Let's call it as a synchronous action, without concern on parallelism.
*/
/* remember context */
pl->client = cntxt;
pl->caller = mbcaller;
pl->env = stk;
pl->pci = pci;
pl->inuse = 1;
/* inherit debugging */
cmd = stk->cmd;
if ( pl->stk == NULL)
throw(MAL, "factory.new", "internal error, stack frame missing");
/* copy the calling arguments onto the stack
of the factory */
i = psig->retc;
for (k = pci->retc; i < pci->argc; i++, k++) {
lhs = &pl->stk->stk[psig->argv[k]];
/* variable arguments ? */
if (k == psig->argc - 1)
k--;
rhs = &pl->env->stk[getArg(pci, i)];
if (VALcopy(lhs, rhs) == NULL)
throw(MAL, "factory.call", SQLSTATE(HY001) MAL_MALLOC_FAIL);
if( lhs->vtype == TYPE_bat )
BBPretain(lhs->val.bval);
}
if (mb->errors)
throw(MAL, "factory.call", PROGRAM_GENERAL);
if (firstcall ){
/* initialize the stack */
for(i= psig->argc; i< mb->vtop; i++) {
lhs = &pl->stk->stk[i];
if( isVarConstant(mb,i) > 0 ){
if( !isVarDisabled(mb,i)){
rhs = &getVarConstant(mb,i);
if (VALcopy(lhs,rhs) == NULL)
throw(MAL, "factory.call", SQLSTATE(HY001) MAL_MALLOC_FAIL);
}
} else{
lhs->vtype = getVarGDKType(mb,i);
lhs->val.pval = 0;
lhs->len = 0;
}
}
pl->stk->stkbot= mb->vtop; /* stack already initialized */
msg = runMAL(cntxt, mb, 0, pl->stk);
} else {
msg = reenterMAL(cntxt, mb, pl->pc, -1, pl->stk);
}
/* propagate change in debugging status */
if (cmd && pl->stk && pl->stk->cmd != cmd && cmd != 'x')
for (; stk; stk = stk->up)
stk->cmd = pl->stk->cmd;
return msg;
}
int
OPTpushrangesImplementation(Client cntxt, MalBlkPtr mb, MalStkPtr stk, InstrPtr pci)
{
int i,j, limit,actions=0;
InstrPtr p, *old;
int x,y,z;
Range range;
if( mb->errors)
return 0;
range= (Range) GDKzalloc(mb->vtop * sizeof(RangeRec));
if (range == NULL)
return 0;
OPTDEBUGpushranges
mnstr_printf(cntxt->fdout,"#Range select optimizer started\n");
(void) stk;
(void) pci;
limit = mb->stop;
old = mb->stmt;
/*
* In phase I we collect information about constants
*/
for (i = 0; i < limit; i++) {
p = old[i];
if( p->barrier)
break; /* end of optimizer */
for(j=p->retc; j< p->argc; j++)
range[getArg(p,j)].used++;
for(j=0; j<p->retc; j++){
range[getArg(p,j)].lastupdate= i;
if( range[getArg(p,j)].lastrange == 0)
range[getArg(p,j)].lastrange= i;
}
if( getModuleId(p)== algebraRef &&
( getFunctionId(p)== selectRef || getFunctionId(p)== uselectRef) ){
/*
* The operation X:= algebra.select(Y,L,H,Li,Hi) is analysed.
* First, we attempt to propagate the range known for Y onto the
* requested range of X. This may lead to smaller range of
* even the conclusion that X is necessarily empty.
* Of course, only under the condition that Y has not been changed by a
* side-effect since it was bound to X.
*/
x= getArg(p,1);
y= getArg(p,2);
if( range[x].lcst && isVarConstant(mb,y) ){
/* merge lowerbound */
if( ATOMcmp( getVarGDKType(mb,y),
VALptr( &getVarConstant(mb,range[x].lcst)),
VALptr( &getVarConstant(mb,y)) ) > 0){
getArg(p,2)= range[x].lcst;
z= range[x].srcvar;
if( getArg(p,1) == x &&
range[z].lastupdate == range[z].lastrange){
getArg(p,1) = z;
actions++;
}
}
y= getArg(p,3);
/* merge higherbound */
if( ATOMcmp( getVarGDKType(mb,y),
VALptr( &getVarConstant(mb,range[x].hcst)),
VALptr( &getVarConstant(mb,y)) ) < 0 ||
ATOMcmp( getVarGDKType(mb,y),
VALptr( &getVarConstant(mb,y)),
ATOMnilptr(getVarType(mb,y)) ) == 0){
getArg(p,3)= range[x].hcst;
z= range[x].srcvar;
if( getArg(p,1) == x && range[z].lastupdate == range[z].lastrange){
getArg(p,1) = z;
actions++;
}
}
}
/*
* The second step is to assign the result of this exercise to the
* result variable.
*/
x= getArg(p,0);
if( isVarConstant(mb, getArg(p,2)) ){
range[x].lcst = getArg(p,2);
range[x].srcvar= getArg(p,1);
range[x].lastupdate= range[x].lastrange = i;
}
if( isVarConstant(mb, getArg(p,3)) ){
range[x].hcst = getArg(p,3);
range[x].srcvar= getArg(p,1);
range[x].lastupdate= range[x].lastrange = i;
}
/*
* If both range bounds are constant, we can also detect empty results.
* It is empty if L> H or when L=H and the bounds are !(true,true).
*/
x= getArg(p,2);
y= getArg(p,3);
if( isVarConstant(mb, x) &&
isVarConstant(mb, y) ){
z =ATOMcmp( getVarGDKType(mb,y),
VALptr( &getVarConstant(mb,x)),
VALptr( &getVarConstant(mb,y)));
x= p->argc > 4;
x= x && isVarConstant(mb,getArg(p,4));
x= x && isVarConstant(mb,getArg(p,5));
x= x && getVarConstant(mb,getArg(p,4)).val.btval;
x= x && getVarConstant(mb,getArg(p,5)).val.btval;
if( z > 0 || (z==0 && p->argc>4 && !x)) {
int var = getArg(p, 0);
wrd zero = 0;
ValRecord v, *vp;
vp = VALset(&v, TYPE_wrd, &zero);
varSetProp(mb, var, rowsProp, op_eq, vp);
/* create an empty replacement */
x = getArgType(mb, p, 1);
p->argc=1;
getModuleId(p)= batRef;
getFunctionId(p)= newRef;
p= pushArgument(mb,p, newTypeVariable(mb, getHeadType(x)));
(void) pushArgument(mb,p, newTypeVariable(mb, getTailType(x)));
actions++;
}
}
}
}
OPTDEBUGpushranges
for(j=0; j< mb->vtop; j++)
if( range[j].used )
printRange(cntxt, mb,range,j);
/*
* Phase II, if we succeeded in pushing constants around and
* changing instructions, we might as well try once more to perform
* aliasRemoval, constantExpression, and pushranges.
*/
GDKfree(range);
return actions;
}
/*
* The shortcut operator for factory calls assumes that the user is
* not interested in the results produced.
*/
str
callFactory(Client cntxt, MalBlkPtr mb, ValPtr argv[], char flag){
Plant pl;
InstrPtr psig = getInstrPtr(mb, 0);
int i;
ValPtr lhs,rhs;
MalStkPtr stk;
str ret;
i= findPlant(mb);
if( i< 0) {
/* first call? prepare the factory */
pl = newPlant(mb);
if (pl == NULL)
throw(MAL, "factory.call", SQLSTATE(HY001) MAL_MALLOC_FAIL);
/* remember context, which does not exist. */
pl->client = cntxt;
pl->caller = 0;
pl->env = 0;
pl->pci = 0;
pl->inuse = 1;
stk = pl->stk;
/* initialize the stack */
stk->stktop= mb->vtop;
stk->stksize= mb->vsize;
stk->blk= mb;
stk->up = 0;
stk->cmd= flag;
/* initialize the stack */
for(i= psig->argc; i< mb->vtop; i++)
if( isVarConstant(mb,i) > 0 ){
lhs = &stk->stk[i];
rhs = &getVarConstant(mb,i);
if (VALcopy(lhs,rhs) == NULL)
throw(MAL, "factory.call", SQLSTATE(HY001) MAL_MALLOC_FAIL);
} else {
lhs = &stk->stk[i];
lhs->vtype = getVarGDKType(mb,i);
}
pl->stk= stk;
} else {
pl= plants+i;
/*
* When you re-enter the factory the old arguments should be
* released to make room for the new ones.
*/
for (i = psig->retc; i < psig->argc; i++) {
lhs = &pl->stk->stk[psig->argv[i]];
if( lhs->vtype == TYPE_bat )
BBPrelease(lhs->val.bval);
}
}
/* copy the calling arguments onto the stack of the factory */
i = psig->retc;
for (i = psig->retc; i < psig->argc; i++) {
lhs = &pl->stk->stk[psig->argv[i]];
if (VALcopy(lhs, argv[i]) == NULL)
throw(MAL, "factory.call", SQLSTATE(HY001) MAL_MALLOC_FAIL);
if( lhs->vtype == TYPE_bat )
BBPretain(lhs->val.bval);
}
ret= reenterMAL(cntxt, mb, pl->pc, -1, pl->stk);
/* garbage collect the string arguments, these positions
will simply be overwritten the next time.
for (i = psig->retc; i < psig->argc; i++)
garbageElement(lhs = &pl->stk->stk[psig->argv[i]]);
*/
return ret;
}
/*
* 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;
}
