/**
* \param obj the objet to remove from the swag
* \param swag a swag
* \return \a obj if it was in the \a swag and NULL otherwise
*
* removes \a obj from \a swag
*/
XBT_INLINE void *xbt_swag_remove(void *obj, xbt_swag_t swag)
{
if (!obj)
return NULL;
size_t offset = swag->offset;
void* prev = xbt_swag_getPrev(obj, offset);
void* next = xbt_swag_getNext(obj, offset);
if (prev) {
xbt_swag_getNext(prev, offset) = next;
xbt_swag_getPrev(obj, offset) = NULL;
if (next) {
xbt_swag_getPrev(next, offset) = prev;
xbt_swag_getNext(obj, offset) = NULL;
}
else {
swag->tail = prev;
}
swag->count--;
}
else if (next) {
xbt_swag_getPrev(next, offset) = NULL;
xbt_swag_getNext(obj, offset) = NULL;
swag->head = next;
swag->count--;
}
else if (obj == swag->head) {
swag->head = swag->tail = NULL;
swag->count--;
}
return obj;
}
//if we modify the swag between calls, normal version may loop forever
//this safe version ensures that we browse the swag elements only once
lmm_variable_t lmm_get_var_from_cnst_safe(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem,
lmm_element_t * nextelem, int * numelem)
{
if (!(*elem)){
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->enabled_element_set));
*numelem = xbt_swag_size(&(cnst->enabled_element_set))+xbt_swag_size(&(cnst->disabled_element_set))-1;
if (!(*elem))
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
}else{
*elem = *nextelem;
if(*numelem>0){
(*numelem) --;
}else
return NULL;
}
if (*elem){
//elem is not null, so we carry on
if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
//Look at enabled_element_set, and jump to disabled_element_set when finished
*nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
if (!(*nextelem))
*nextelem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
} else {
*nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);
}
return (*elem)->variable;
}else
return NULL;
}
/**
* \param obj the objet to insert in the swag
* \param swag a swag
*
* insert (at the tail... you probably had a very good reason to do
* that, I hope you know what you're doing) \a obj in \a swag
*/
XBT_INLINE void xbt_swag_insert_at_tail(void *obj, xbt_swag_t swag)
{
xbt_assert(!xbt_swag_belongs(obj, swag) || swag->tail,
"This object belongs to an empty swag! Did you correctly initialize the object's hookup?");
if (!swag->head) {
xbt_assert(!(swag->tail), "Inconsistent swag.");
swag->head = obj;
swag->tail = obj;
swag->count++;
}
else if (obj != swag->tail && !xbt_swag_getNext(obj, swag->offset)) {
xbt_swag_getPrev(obj, swag->offset) = swag->tail;
xbt_swag_getNext(swag->tail, swag->offset) = obj;
swag->tail = obj;
swag->count++;
}
}
/**
* \param swag a swag
* \return an object from the \a swag
*/
void *xbt_swag_extract(xbt_swag_t swag)
{
if (!swag->head)
return NULL;
size_t offset = swag->offset;
void* obj = swag->head;
if (obj == swag->tail) { /* special case */
swag->head = swag->tail = NULL;
} else {
swag->head = xbt_swag_getNext(obj, offset);
xbt_swag_getPrev(swag->head, offset) = NULL;
xbt_swag_getNext(obj, offset) = NULL;
}
(swag->count)--;
return obj;
}
lmm_variable_t lmm_get_var_from_cnst(lmm_system_t /*sys*/,
lmm_constraint_t cnst,
lmm_element_t * elem)
{
if (!(*elem))
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->element_set));
else
*elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->element_set.offset);
if (*elem)
return (*elem)->variable;
else
return NULL;
}
lmm_variable_t lmm_get_var_from_cnst(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem)
{
if (!(*elem)) {
// That is the first call, pick the first element among enabled_element_set (or disabled_element_set if
// enabled_element_set is empty)
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->enabled_element_set));
if (!(*elem))
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
} else {
//elem is not null, so we carry on
if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
//Look at enabled_element_set, and jump to disabled_element_set when finished
*elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
if (!(*elem))
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
} else {
*elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);
}
}
if (*elem)
return (*elem)->variable;
else
return NULL;
}
