/**
* @abstract add a new link instance to the AthenaTransportLinkAdapter instance list
* @discussion
*
* When athenaTransportLinkAdapter_Open is called on a link specific module, the module instantiates
* the link and then creates a new AthenaTransportLink to interface with the AthenaTransportLinkAdapter.
* The AthenaTransportLinkModule passes the new AthenaTransportLink to the AthenaTransportLinkAdapter by
* calling AthenaTransportLinkAdapter_AddLink with the new link AthenaTransportLink data. The AthenaTransportLinkAdapter
* then places the new link instance on its internal instance list in a pending state until it has been verified and ensures
* that the new link doesn't collide (i.e. by name) with any currently registered link before returning success.
*
* New routable links are placed into instanceList slots that have previously been vacated before being added
* to the end of the instanceList. This is in order to keep bit vectors that are based on the instanceList as
* small as is necessary.
*
* @param [in] athenaTransportLinkAdapter link adapter instance
* @param [in] linkInstance instance structure created by the link specific module
* @return 0 on success, -1 with errno set to indicate the error
*
* Example:
* @code
* {
* }
* @endcode
*/
static int
_athenaTransportLinkAdapter_AddLink(AthenaTransportLinkAdapter *athenaTransportLinkAdapter, AthenaTransportLink *newTransportLink)
{
int linkId = -1;
// Check for existing linkName in listenerList
if (athenaTransportLinkAdapter->listenerList) {
for (int index = 0; index < parcArrayList_Size(athenaTransportLinkAdapter->listenerList); index++) {
AthenaTransportLink *athenaTransportLink = parcArrayList_Get(athenaTransportLinkAdapter->listenerList, index);
if (strcmp(athenaTransportLink_GetName(athenaTransportLink), athenaTransportLink_GetName(newTransportLink)) == 0) {
errno = EADDRINUSE; // name is already in listenerList
return -1;
}
}
}
// Check for existing linkName in the instanceList
if (athenaTransportLinkAdapter->instanceList) {
for (int index = 0; index < parcArrayList_Size(athenaTransportLinkAdapter->instanceList); index++) {
AthenaTransportLink *athenaTransportLink = parcArrayList_Get(athenaTransportLinkAdapter->instanceList, index);
if (athenaTransportLink) {
if (strcmp(athenaTransportLink_GetName(athenaTransportLink), athenaTransportLink_GetName(newTransportLink)) == 0) {
errno = EADDRINUSE; // name is already in instanceList
return -1;
}
} else {
// remember the first available index found along the way
if (linkId == -1) {
linkId = index;
}
}
}
}
// Add to listenerList or instanceList
athenaTransportLink_Acquire(newTransportLink);
if (athenaTransportLink_IsNotRoutable(newTransportLink)) { // listener
bool result = parcArrayList_Add(athenaTransportLinkAdapter->listenerList, newTransportLink);
assertTrue(result, "parcArrayList_Add failed to add new listener");
} else { // routable link, add to instances using the last available id if one was seen
if (linkId != -1) {
parcArrayList_Set(athenaTransportLinkAdapter->instanceList, linkId, newTransportLink);
} else {
bool result = parcArrayList_Add(athenaTransportLinkAdapter->instanceList, newTransportLink);
assertTrue(result, "parcArrayList_Add failed to add new link instance");
}
}
// If any transport link has a registered file descriptor add it to the general polling list.
int eventFd = athenaTransportLink_GetEventFd(newTransportLink);
if (eventFd != -1) {
_add_to_pollfdList(athenaTransportLinkAdapter, newTransportLink, eventFd);
}
return 0;
}
/**
* @abstract called from below the link adapter to coordinate termination of a link instance
* @discussion
*
* This is called exclusively from the Transport Link Module to instigate the removal of
* an active link. The link has been flagged closing by the originator. This method
* must ensure that all references to the link have been removed and then call the
* instance close method to finish the operation.
*
* @param [in] athenaTransportLinkAdapter link adapter instance
* @param [in] athenaTransportLink link instance to remove
*
* Example:
* @code
* {
*
* }
* @endcode
*/
static void
_athenaTransportLinkAdapter_RemoveLink(AthenaTransportLinkAdapter *athenaTransportLinkAdapter, AthenaTransportLink *athenaTransportLink)
{
int linkId = -1;
// if this is a listener it can simply be removed
if (athenaTransportLink_IsNotRoutable(athenaTransportLink)) {
if (athenaTransportLinkAdapter->listenerList) {
for (int index = 0; index < parcArrayList_Size(athenaTransportLinkAdapter->listenerList); index++) {
AthenaTransportLink *transportLink = parcArrayList_Get(athenaTransportLinkAdapter->listenerList, index);
if (athenaTransportLink == transportLink) {
parcArrayList_RemoveAtIndex(athenaTransportLinkAdapter->listenerList, index);
_remove_from_pollfdList(athenaTransportLinkAdapter, athenaTransportLink);
parcLog_Debug(athenaTransportLinkAdapter_GetLogger(athenaTransportLinkAdapter), "listener removed: %s",
athenaTransportLink_GetName(athenaTransportLink));
athenaTransportLink_Release(&athenaTransportLink);
return;
}
}
}
}
// Remove from our internal instance list.
// The index entry remains to be reused by links that are added in the future.
if (athenaTransportLinkAdapter->instanceList) {
for (int index = 0; index < parcArrayList_Size(athenaTransportLinkAdapter->instanceList); index++) {
AthenaTransportLink *transportLink = parcArrayList_Get(athenaTransportLinkAdapter->instanceList, index);
if (athenaTransportLink == transportLink) {
parcArrayList_Set(athenaTransportLinkAdapter->instanceList, index, NULL);
_remove_from_pollfdList(athenaTransportLinkAdapter, athenaTransportLink);
linkId = index;
break;
}
}
}
assertFalse(linkId == -1, "Attempt to remove link not found in link adapter lists");
// Callback to notify that the link has been removed and references need to be dropped.
PARCBitVector *linkVector = parcBitVector_Create();
parcBitVector_Set(linkVector, linkId);
athenaTransportLinkAdapter->removeLink(athenaTransportLinkAdapter->removeLinkContext, linkVector);
parcBitVector_Release(&linkVector);
// we assume all references to the linkId associated with this instance have been
// cleared from the PIT and FIB when removeLink returns.
parcLog_Debug(athenaTransportLinkAdapter_GetLogger(athenaTransportLinkAdapter),
"link removed: %s", athenaTransportLink_GetName(athenaTransportLink));
athenaTransportLink_Release(&athenaTransportLink);
}