/**
* scaffolding for send a signal from ouside the VMhost
*
* <b>Examples (from test suite):</b>
* @snippet spec/vmhost_spec.h testVMHostActivateReceptor
*/
void _v_send(VMHost *v,ReceptorAddress from,ReceptorAddress to,Aspect aspect,Symbol carrier,T *contents) {
T *s = __r_make_signal(from,to,aspect,carrier,contents,0,0);
T *x = _r_send(v->r,s);
_t_free(x);
}
/**
* reduce system level processes in a run tree. Assumes that the children have already been
* reduced and all parameters have been filled in
*
* these system level processes are the equivalent of the instruction set of the ceptr virtual machine
*/
Error __p_reduce_sys_proc(R *context,Symbol s,T *code) {
int b,c;
char *str;
Symbol sy;
T *x,*t,*match_results,*match_tree;
Error err = noReductionErr;
switch(s.id) {
case NOOP_ID:
// noop simply replaces itself with it's own child
x = _t_detach_by_idx(code,1);
break;
case IF_ID:
t = _t_child(code,1);
b = (*(int *)_t_surface(t)) ? 2 : 3;
x = _t_detach_by_idx(code,b);
break;
case ADD_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = c+*((int *)&x->contents.surface);
break;
case SUB_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)-c;
break;
case MULT_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)*c;
break;
case DIV_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
if (!c) {
_t_free(x);
return divideByZeroReductionErr;
}
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)/c;
break;
case MOD_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
if (!c) {
_t_free(x);
return divideByZeroReductionErr;
}
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)%c;
break;
case EQ_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)==c;
x->contents.symbol = BOOLEAN;
break;
case LT_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)<c;
x->contents.symbol = BOOLEAN;
break;
case GT_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)>c;
x->contents.symbol = BOOLEAN;
break;
case LTE_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)<=c;
x->contents.symbol = BOOLEAN;
break;
case GTE_INT_ID:
x = _t_detach_by_idx(code,1);
c = *(int *)_t_surface(_t_child(code,1));
*((int *)&x->contents.surface) = *((int *)&x->contents.surface)>=c;
x->contents.symbol = BOOLEAN;
break;
case CONCAT_STR_ID:
// if the first parameter is a RESULT SYMBOL then we use that as the symbol type for the result tree.
x = _t_detach_by_idx(code,1);
sy = _t_symbol(x);
if (semeq(RESULT_SYMBOL,sy)) {
sy = *(Symbol *)_t_surface(x);
_t_free(x);
x = _t_detach_by_idx(code,1);
}
//@todo, add a bunch of sanity checking here to make sure the
// parameters are all CSTRINGS
c = _t_children(code);
// make sure the surface was allocated and if not, converted to an alloced surface
if (c > 0) {
if (!(x->context.flags & TFLAG_ALLOCATED)) {
int v = *((int *)&x->contents.surface); // copy the string as an integer
str = (char *)&v; // calculate the length
int size = strlen(str)+1;
x->contents.surface = malloc(size);
memcpy(x->contents.surface,str,size);
t->context.flags = TFLAG_ALLOCATED;
}
}
// @todo this would probably be faster with just one total realloc for all children
for(b=1;b<=c;b++) {
str = (char *)_t_surface(_t_child(code,b));
int size = strlen(str);
x->contents.surface = realloc(x->contents.surface,x->contents.size+size);
memcpy(x->contents.surface+x->contents.size-1,str,size);
x->contents.size+=size;
*( (char *)x->contents.surface + x->contents.size -1) = 0;
}
x->contents.symbol = sy;
break;
case RESPOND_ID:
{
T *signal = _t_parent(context->run_tree);
if (!signal || !semeq(_t_symbol(signal),SIGNAL))
return notInSignalContextReductionError;
T *response_contents = _t_detach_by_idx(code,1);
T *envelope = _t_child(signal,1);
Xaddr to = *(Xaddr *)_t_surface(_t_child(envelope,1)); // reverse the from and to
Xaddr from = *(Xaddr *)_t_surface(_t_child(envelope,2));
Aspect a = *(Aspect *)_t_surface(_t_child(envelope,3));
// add the response signal into the outgoing signals list of the root
// run-tree (which is always the last child)
R *root = context;
while (context->caller) root = context->caller;
int kids = _t_children(root->run_tree);
T *signals;
if (kids == 1 || (!semeq(SIGNALS,_t_symbol(signals = _t_child(root->run_tree,kids)))))
signals = _t_newr(root->run_tree,SIGNALS); // make signals list if it's not there
T *response = __r_make_signal(from,to,a,response_contents);
_t_add(signals,response);
x = _t_newi(0,TEST_INT_SYMBOL,0);
}
// @todo figure what RESPOND should return, since really it's a side-effect instruction
// perhaps some kind of signal context symbol or something. Right now using TEST_INT_SYMBOL
// as a bogus placeholder.
break;
case QUOTE_ID:
x = _t_detach_by_idx(code,1);
break;
case EXPECT_ACT_ID:
// detach the carrier and expectation and construction params, and enqueue the expectation and action
// on the carrier
{
T *carrier_param = _t_detach_by_idx(code,1);
T *carrier = *(T **)_t_surface(carrier_param);
_t_free(carrier_param);
T *ex = _t_detach_by_idx(code,1);
T *expectation = _t_new_root(EXPECTATION);
_t_add(expectation,ex);
T *params = _t_detach_by_idx(code,1);
//@todo: this is a fake way to add an expectation to a carrier (as a c pointer
// out of the params)
// we probably actually need a system representation for carriers and an API
// that will also make this thread safe. For example, in the case of carrier being
// a receptor's aspect/flux then we should be using _r_add_listener here, but
// unfortunately we don't want to have to know about receptors this far down in the
// stack... But it's not clear yet how we do know about the listening context as
// I don't think it should be copied into every execution context (the R struct)
_t_add(carrier,expectation);
_t_add(carrier,params);
// the action is a pointer back to this context for now were using a EXPECT_ACT
// with the c pointer as the surface because I don't know what else to do... @fixme
// perhaps this should be a BLOCKED_EXPECT_ACTION process or something...
_t_new(carrier,EXPECT_ACT,&context,sizeof(context));
}
rt_cur_child(code) = 1; // reset the current child count on the code
x = _t_detach_by_idx(code,1);
// the actually blocking happens in redcueq which can remove the process from the
// round-robin
err = Block;
break;
case SEND_ID:
{
T *t = _t_detach_by_idx(code,1);
Xaddr to = *(Xaddr *)_t_surface(t);
_t_free(t);
T* signal_contents = _t_detach_by_idx(code,1);
Xaddr from = {RECEPTOR_XADDR,0}; //@todo how do we say SELF??
x = __r_make_signal(from,to,DEFAULT_ASPECT,signal_contents);
}
err = Send;
break;
case INTERPOLATE_FROM_MATCH_ID:
match_results = _t_child(code,2);
match_tree = _t_child(code,3);
x = _t_detach_by_idx(code,1);
// @todo interpolation errors?
_p_interpolate_from_match(x,match_results,match_tree);
break;
case RAISE_ID:
return raiseReductionErr;
break;
case READ_STREAM_ID:
{
T *s = _t_detach_by_idx(code,1);
FILE *stream =*(FILE**)_t_surface(s);
_t_free(s);
s = _t_detach_by_idx(code,1);
sy = _t_symbol(s);
if (semeq(RESULT_SYMBOL,sy)) {
sy = *(Symbol *)_t_surface(s);
_t_free(s);
int ch;
char buf[1000]; //@todo handle buffer dynamically
int i = 0;
while ((ch = fgetc (stream)) != EOF && ch != '\n' && i < 1000)
buf[i++] = ch;
if (i>=1000) {raise_error0("buffer overrun in READ_STREAM");}
buf[i++]=0;
x = _t_new(0,sy,buf,i);
}
else {raise_error0("expecting RESULT_SYMBOL");}
}
break;
default:
raise_error("unknown sys-process id: %d",s.id);
}
// any remaining children of 'code' are the parameters which have all now been "used up"
// so we can call the low-level __t_free the clean them up and then replace the contents of
// the 'code' node with the contents of the 'x' node that was either detached or produced
// by the the process that just ran
__t_free(code);
code->structure.child_count = x->structure.child_count;
code->structure.children = x->structure.children;
code->contents = x->contents;
code->context = x->context;
free(x);
return err;
}
