static void LinkBarrierElement (TRI_barrier_t* element,
TRI_barrier_list_t* container) {
assert(container != NULL);
element->_container = container;
TRI_LockSpin(&container->_lock);
// empty list
if (container->_end == NULL) {
element->_next = NULL;
element->_prev = NULL;
container->_begin = element;
container->_end = element;
}
// add to the end
else {
element->_next = NULL;
element->_prev = container->_end;
container->_end->_next = element;
container->_end = element;
}
if (element->_type == TRI_BARRIER_ELEMENT) {
// increase counter for barrier elements
++container->_numBarrierElements;
}
TRI_UnlockSpin(&container->_lock);
}
static void LinkBarrierElement (TRI_barrier_t* element, TRI_barrier_list_t* container) {
element->_container = container;
TRI_LockSpin(&container->_lock);
// empty list
if (container->_end == NULL) {
element->_next = NULL;
element->_prev = NULL;
container->_begin = element;
container->_end = element;
}
// add to the end
else {
element->_next = NULL;
element->_prev = container->_end;
container->_end->_next = element;
container->_end = element;
}
TRI_UnlockSpin(&container->_lock);
}
bool TRI_ContainsBarrierList (TRI_barrier_list_t* container,
TRI_barrier_type_e type) {
TRI_LockSpin(&container->_lock);
if (type == TRI_BARRIER_ELEMENT) {
// shortcut
bool hasBarriers = (container->_numBarrierElements > 0);
TRI_UnlockSpin(&container->_lock);
return hasBarriers;
}
TRI_barrier_t* ptr = container->_begin;
while (ptr != NULL) {
if (ptr->_type == type) {
TRI_UnlockSpin(&container->_lock);
return true;
}
ptr = ptr->_next;
}
TRI_UnlockSpin(&container->_lock);
return false;
}
void TRI_FreeBarrier (TRI_barrier_t* element) {
TRI_barrier_list_t* container;
container = element->_container;
TRI_LockSpin(&container->_lock);
// element is at the beginning of the chain
if (element->_prev == NULL) {
container->_begin = element->_next;
}
else {
element->_prev->_next = element->_next;
}
// element is at the end of the chain
if (element->_next == NULL) {
container->_end = element->_prev;
}
else {
element->_next->_prev = element->_prev;
}
TRI_UnlockSpin(&container->_lock);
// free data contained in the element
// currently, only barriers of type ELEMENT contain data that needs freeing
FreeDataBarrier(element);
// free the element
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
}
void TRI_FreeBarrier (TRI_barrier_t* element) {
TRI_barrier_list_t* container;
assert(element != NULL);
container = element->_container;
assert(container != NULL);
TRI_LockSpin(&container->_lock);
// element is at the beginning of the chain
if (element->_prev == NULL) {
container->_begin = element->_next;
}
else {
element->_prev->_next = element->_next;
}
// element is at the end of the chain
if (element->_next == NULL) {
container->_end = element->_prev;
}
else {
element->_next->_prev = element->_prev;
}
if (element->_type == TRI_BARRIER_ELEMENT) {
// decrease counter for barrier elements
--container->_numBarrierElements;
}
TRI_UnlockSpin(&container->_lock);
// free the element
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
}
static bool CheckTerminateFlag (TRI_replication_applier_t* applier) {
TRI_LockSpin(&applier->_threadLock);
bool result = applier->_terminateThread;
TRI_UnlockSpin(&applier->_threadLock);
return result;
}
void TRI_FreeBarrier (TRI_barrier_t* element) {
TRI_barrier_list_t* container;
container = element->_container;
TRI_LockSpin(&container->_lock);
// element is at the beginning of the chain
if (element->_prev == NULL) {
container->_begin = element->_next;
}
else {
element->_prev->_next = element->_next;
}
// element is at the end of the chain
if (element->_next == NULL) {
container->_end = element->_prev;
}
else {
element->_next->_prev = element->_prev;
}
TRI_UnlockSpin(&container->_lock);
// free the element
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
}
void TRI_ReleaseGeneralCursor (TRI_general_cursor_t* cursor) {
TRI_general_cursor_store_t* store = cursor->_store;
TRI_LockSpin(&store->_lock);
cursor = static_cast<TRI_general_cursor_t*>(TRI_LookupByKeyAssociativePointer(&store->_ids, &cursor->_id));
if (cursor != NULL) {
--cursor->_usage._refCount;
}
TRI_UnlockSpin(&store->_lock);
}
TRI_voc_tick_t TRI_NewTickVocBase () {
uint64_t tick = ServerIdentifier;
TRI_LockSpin(&TickLock);
tick |= (++CurrentTick) << 16;
TRI_UnlockSpin(&TickLock);
return tick;
}
TRI_general_cursor_t* TRI_FindGeneralCursor (TRI_vocbase_t* vocbase,
TRI_voc_tick_t id) {
TRI_general_cursor_store_t* store = vocbase->_cursors;
TRI_LockSpin(&store->_lock);
TRI_general_cursor_t* cursor = static_cast<TRI_general_cursor_t*>(TRI_LookupByKeyAssociativePointer(&store->_ids, &id));
if (cursor == NULL || cursor->_usage._isDeleted) {
cursor = NULL;
}
TRI_UnlockSpin(&store->_lock);
return cursor;
}
TRI_general_cursor_t* TRI_CreateGeneralCursor (TRI_vocbase_t* vocbase,
TRI_general_cursor_result_t* result,
const bool doCount,
const TRI_general_cursor_length_t batchSize,
TRI_json_t* extra) {
TRI_general_cursor_t* cursor;
TRI_ASSERT(vocbase != NULL);
cursor = (TRI_general_cursor_t*) TRI_Allocate(TRI_UNKNOWN_MEM_ZONE, sizeof(TRI_general_cursor_t), false);
if (cursor == NULL) {
return NULL;
}
cursor->_vocbase = vocbase;
cursor->_store = vocbase->_cursors;
cursor->_result = result;
cursor->_extra = extra; // might be NULL
cursor->_expires = TRI_microtime() + 3600; // default lifetime: 1h
cursor->_id = TRI_NewTickServer();
// state
cursor->_currentRow = 0;
cursor->_length = result->getLength(result);
cursor->_hasCount = doCount;
cursor->_batchSize = batchSize;
cursor->_usage._refCount = 0;
cursor->_usage._isDeleted = false;
// assign functions
cursor->next = NextGeneralCursor;
cursor->hasNext = HasNextGeneralCursor;
cursor->hasCount = HasCountGeneralCursor;
cursor->getBatchSize = GetBatchSizeGeneralCursor;
cursor->getExtra = GetExtraGeneralCursor;
cursor->free = TRI_FreeGeneralCursor;
TRI_InitSpin(&cursor->_lock);
TRI_LockSpin(&vocbase->_cursors->_lock);
// TODO: check for errors here
TRI_InsertKeyAssociativePointer(&vocbase->_cursors->_ids, &cursor->_id, cursor, true);
TRI_UnlockSpin(&vocbase->_cursors->_lock);
LOG_TRACE("created general cursor");
return cursor;
}
bool TRI_RemoveGeneralCursor (TRI_vocbase_t* vocbase,
TRI_voc_tick_t id) {
TRI_general_cursor_store_t* store = vocbase->_cursors;
bool result;
TRI_LockSpin(&store->_lock);
TRI_general_cursor_t* cursor = static_cast<TRI_general_cursor_t*>(TRI_LookupByKeyAssociativePointer(&store->_ids, &id));
if (cursor == NULL || cursor->_usage._isDeleted) {
result = false;
}
else {
cursor->_usage._isDeleted = true;
result = true;
}
TRI_UnlockSpin(&store->_lock);
return result;
}
bool TRI_DropGeneralCursor (TRI_general_cursor_t* cursor) {
TRI_general_cursor_store_t* store = cursor->_store;
bool result;
TRI_LockSpin(&store->_lock);
cursor = static_cast<TRI_general_cursor_t*>(TRI_LookupByKeyAssociativePointer(&store->_ids, &cursor->_id));
if (cursor != NULL && ! cursor->_usage._isDeleted) {
cursor->_usage._isDeleted = true;
result = true;
}
else {
result = false;
}
TRI_UnlockSpin(&store->_lock);
return result;
}
TRI_general_cursor_t* TRI_UseGeneralCursor (TRI_general_cursor_t* cursor) {
TRI_general_cursor_store_t* store = cursor->_store;
TRI_LockSpin(&store->_lock);
cursor = static_cast<TRI_general_cursor_t*>(TRI_LookupByKeyAssociativePointer(&store->_ids, &cursor->_id));
if (cursor != NULL) {
if (cursor->_usage._isDeleted) {
cursor = NULL;
}
else {
++cursor->_usage._refCount;
}
}
TRI_UnlockSpin(&store->_lock);
return cursor;
}
bool TRI_ContainsBarrierList (TRI_barrier_list_t* container, TRI_barrier_type_e type) {
TRI_barrier_t* ptr;
TRI_LockSpin(&container->_lock);
ptr = container->_begin;
while (ptr != NULL) {
if (ptr->_type == type) {
TRI_UnlockSpin(&container->_lock);
return true;
}
ptr = ptr->_next;
}
TRI_UnlockSpin(&container->_lock);
return false;
}
static void CleanupSimCollection (TRI_sim_collection_t* sim) {
// loop until done
while (true) {
TRI_barrier_list_t* container;
TRI_barrier_t* element;
bool hasUnloaded = false;
container = &sim->base._barrierList;
element = NULL;
// check and remove a callback elements at the beginning of the list
TRI_LockSpin(&container->_lock);
if (container->_begin == NULL || container->_begin->_type == TRI_BARRIER_ELEMENT) {
// did not find anything on top of the barrier list or found an element marker
// this means we must exit
TRI_UnlockSpin(&container->_lock);
return;
}
element = container->_begin;
assert(element);
// found an element to go on with
container->_begin = element->_next;
if (element->_next == NULL) {
container->_end = NULL;
}
else {
element->_next->_prev = NULL;
}
TRI_UnlockSpin(&container->_lock);
// execute callback, sone of the callbacks might delete or free our collection
if (element->_type == TRI_BARRIER_DATAFILE_CALLBACK) {
TRI_barrier_datafile_cb_t* de;
de = (TRI_barrier_datafile_cb_t*) element;
de->callback(de->_datafile, de->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
// next iteration
}
else if (element->_type == TRI_BARRIER_COLLECTION_UNLOAD_CALLBACK) {
// collection is unloaded
TRI_barrier_collection_cb_t* ce;
ce = (TRI_barrier_collection_cb_t*) element;
hasUnloaded = ce->callback(ce->_collection, ce->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
if (hasUnloaded) {
// this has unloaded and freed the collection
return;
}
}
else if (element->_type == TRI_BARRIER_COLLECTION_DROP_CALLBACK) {
// collection is dropped
TRI_barrier_collection_cb_t* ce;
ce = (TRI_barrier_collection_cb_t*) element;
hasUnloaded = ce->callback(ce->_collection, ce->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
if (hasUnloaded) {
// this has dropped the collection
return;
}
}
else {
// unknown type
LOG_FATAL("unknown barrier type '%d'", (int) element->_type);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
}
// next iteration
}
}
void TRI_CleanupGeneralCursor (TRI_general_cursor_store_t* store,
bool force) {
double compareStamp = TRI_microtime();
size_t deleteCount = 0;
// we need an exclusive lock on the index
TRI_LockSpin(&store->_lock);
if (store->_ids._nrUsed == 0) {
// store is empty, nothing to do!
TRI_UnlockSpin(&store->_lock);
return;
}
LOG_TRACE("cleaning shadows. in store: %ld", (unsigned long) store->_ids._nrUsed);
// loop until there's nothing to delete or
// we have deleted CURSOR_MAX_DELETE elements
while (deleteCount++ < CURSOR_MAX_DELETE || force) {
bool deleted = false;
size_t i;
for (i = 0; i < store->_ids._nrAlloc; i++) {
// enum all cursors
TRI_general_cursor_t* cursor = (TRI_general_cursor_t*) store->_ids._table[i];
if (cursor == NULL) {
continue;
}
TRI_LockSpin(&cursor->_lock);
if (force ||
(cursor->_usage._refCount == 0 &&
(cursor->_usage._isDeleted || cursor->_expires < compareStamp))) {
LOG_TRACE("cleaning cursor %p, id: %llu, rc: %d, expires: %d, deleted: %d",
cursor,
(unsigned long long) cursor->_id,
(int) cursor->_usage._refCount,
(int) cursor->_expires,
(int) cursor->_usage._isDeleted);
TRI_RemoveKeyAssociativePointer(&store->_ids, &cursor->_id);
TRI_UnlockSpin(&cursor->_lock);
TRI_FreeGeneralCursor(cursor);
deleted = true;
// the remove might reposition elements in the container.
// therefore break here and start iteration anew
break;
}
TRI_UnlockSpin(&cursor->_lock);
}
if (! deleted) {
// we did not find anything to delete, so give up
break;
}
}
// release lock
TRI_UnlockSpin(&store->_lock);
}
void TRI_LockGeneralCursor (TRI_general_cursor_t* const cursor) {
TRI_LockSpin(&cursor->_lock);
}
static void CleanupDocumentCollection (TRI_document_collection_t* document) {
// loop until done
while (true) {
TRI_barrier_list_t* container;
TRI_barrier_t* element;
bool hasUnloaded = false;
container = &document->base._barrierList;
element = NULL;
// check and remove all callback elements at the beginning of the list
TRI_LockSpin(&container->_lock);
// check the element on top of the barrier list
// if it is a TRI_BARRIER_ELEMENT, it means that there is still a reference held
// to document data in a datafile. We must then not unload or remove a file
if (container->_begin == NULL ||
container->_begin->_type == TRI_BARRIER_ELEMENT ||
container->_begin->_type == TRI_BARRIER_COLLECTION_REPLICATION ||
container->_begin->_type == TRI_BARRIER_COLLECTION_COMPACTION) {
// did not find anything at the head of the barrier list or found an element marker
// this means we must exit and cannot throw away datafiles and can unload collections
TRI_UnlockSpin(&container->_lock);
return;
}
// no TRI_BARRIER_ELEMENT at the head of the barrier list. This means that there is
// some other action we can perform (i.e. unloading a datafile or a collection)
// note that there is no need to check the entire list for a TRI_BARRIER_ELEMENT as
// the list is filled up in chronological order. New barriers are always added to the
// tail of the list, and if we have the following list
// HEAD -> TRI_BARRIER_DATAFILE_CALLBACK -> TRI_BARRIER_ELEMENT
// then it is still safe to execute the datafile callback operation, even if there
// is a TRI_BARRIER_ELEMENT after it.
// This is the case because the TRI_BARRIER_DATAFILE_CALLBACK is only put into the
// barrier list after changing the pointers in all headers. After the pointers are
// changed, it is safe to unload/remove an old datafile (that noone points to). And
// any newer TRI_BARRIER_ELEMENTS will always reference data inside other datafiles.
element = container->_begin;
assert(element);
// found an element to go on with
container->_begin = element->_next;
if (element->_next == NULL) {
container->_end = NULL;
}
else {
element->_next->_prev = NULL;
}
// yes, we can release the lock here
TRI_UnlockSpin(&container->_lock);
// someone else might now insert a new TRI_BARRIER_ELEMENT here, but it will
// always refer to a different datafile than the one that we will now unload
// execute callback, sone of the callbacks might delete or free our collection
if (element->_type == TRI_BARRIER_DATAFILE_DROP_CALLBACK) {
TRI_barrier_datafile_drop_cb_t* de;
de = (TRI_barrier_datafile_drop_cb_t*) element;
de->callback(de->_datafile, de->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
// next iteration
}
else if (element->_type == TRI_BARRIER_DATAFILE_RENAME_CALLBACK) {
TRI_barrier_datafile_rename_cb_t* de;
de = (TRI_barrier_datafile_rename_cb_t*) element;
de->callback(de->_datafile, de->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
// next iteration
}
else if (element->_type == TRI_BARRIER_COLLECTION_UNLOAD_CALLBACK) {
// collection is unloaded
TRI_barrier_collection_cb_t* ce;
ce = (TRI_barrier_collection_cb_t*) element;
hasUnloaded = ce->callback(ce->_collection, ce->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
if (hasUnloaded) {
// this has unloaded and freed the collection
return;
}
}
else if (element->_type == TRI_BARRIER_COLLECTION_DROP_CALLBACK) {
// collection is dropped
TRI_barrier_collection_cb_t* ce;
ce = (TRI_barrier_collection_cb_t*) element;
hasUnloaded = ce->callback(ce->_collection, ce->_data);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, element);
if (hasUnloaded) {
// this has dropped the collection
return;
}
}
else {
// unknown type
LOG_FATAL_AND_EXIT("unknown barrier type '%d'", (int) element->_type);
}
// next iteration
}
}
