1
0
Fork 0
arangodb/arangod/CapConstraint/cap-constraint.c

343 lines
11 KiB
C

////////////////////////////////////////////////////////////////////////////////
/// @brief cap constraint
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2004-2013 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is triAGENS GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
/// @author Copyright 2013, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "cap-constraint.h"
#include "BasicsC/logging.h"
#include "BasicsC/tri-strings.h"
#include "VocBase/document-collection.h"
#include "VocBase/headers.h"
#include "VocBase/server-id.h"
// -----------------------------------------------------------------------------
// --SECTION-- CAP CONSTRAINT
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- private functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup VocBase
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief apply the cap constraint for the collection
////////////////////////////////////////////////////////////////////////////////
static int ApplyCap (TRI_cap_constraint_t* cap,
TRI_primary_collection_t* primary,
TRI_transaction_collection_t* trxCollection) {
TRI_document_collection_t* document;
TRI_headers_t* headers;
int64_t currentSize;
size_t currentCount;
int res;
document = (TRI_document_collection_t*) primary;
headers = document->_headers;
currentCount = headers->count(headers);
currentSize = headers->size(headers);
res = TRI_ERROR_NO_ERROR;
// delete while at least one of the constraints is violated
while ((cap->_count > 0 && currentCount > cap->_count) ||
(cap->_size > 0 && currentSize > cap->_size)) {
TRI_doc_mptr_t* oldest = headers->front(headers);
if (oldest != NULL) {
size_t oldSize;
assert(oldest->_data != NULL);
oldSize = ((TRI_df_marker_t*) (oldest->_data))->_size;
assert(oldSize > 0);
if (trxCollection != NULL) {
res = TRI_DeleteDocumentDocumentCollection(trxCollection, NULL, oldest);
if (res != TRI_ERROR_NO_ERROR) {
LOG_WARNING("cannot cap collection: %s", TRI_errno_string(res));
break;
}
}
else {
headers->unlink(headers, oldest);
}
currentCount--;
currentSize -= (int64_t) oldSize;
}
else {
// we should not get here
LOG_WARNING("logic error in %s", __FUNCTION__);
break;
}
}
return res;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief initialise the cap constraint
////////////////////////////////////////////////////////////////////////////////
static int InitialiseCap (TRI_cap_constraint_t* cap,
TRI_primary_collection_t* primary) {
TRI_document_collection_t* document;
TRI_headers_t* headers;
size_t currentCount;
int64_t currentSize;
TRI_ASSERT_MAINTAINER(cap->_count > 0 || cap->_size > 0);
document = (TRI_document_collection_t*) primary;
headers = document->_headers;
currentCount = headers->count(headers);
currentSize = headers->size(headers);
if ((cap->_count >0 && currentCount <= cap->_count) &&
(cap->_size > 0 && currentSize <= cap->_size)) {
// nothing to do
return TRI_ERROR_NO_ERROR;
}
else {
TRI_vocbase_t* vocbase;
TRI_transaction_t* trx;
TRI_voc_cid_t cid;
int res;
vocbase = primary->base._vocbase;
cid = primary->base._info._cid;
trx = TRI_CreateTransaction(vocbase->_transactionContext, TRI_GetServerId(), true, 0.0, false);
if (trx == NULL) {
return TRI_ERROR_OUT_OF_MEMORY;
}
res = TRI_AddCollectionTransaction(trx, cid, TRI_TRANSACTION_WRITE, TRI_TRANSACTION_TOP_LEVEL);
if (res == TRI_ERROR_NO_ERROR) {
TRI_transaction_collection_t* trxCollection;
trxCollection = TRI_GetCollectionTransaction(trx, cid, TRI_TRANSACTION_WRITE);
if (trxCollection != NULL) {
res = TRI_BeginTransaction(trx, (TRI_transaction_hint_t) TRI_TRANSACTION_HINT_LOCK_NEVER, TRI_TRANSACTION_TOP_LEVEL);
if (res == TRI_ERROR_NO_ERROR) {
res = ApplyCap(cap, primary, trxCollection);
if (res == TRI_ERROR_NO_ERROR) {
res = TRI_CommitTransaction(trx, TRI_TRANSACTION_TOP_LEVEL);
}
else {
TRI_AbortTransaction(trx, TRI_TRANSACTION_TOP_LEVEL);
}
}
}
else {
res = TRI_ERROR_INTERNAL;
}
}
TRI_FreeTransaction(trx);
return res;
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief return the index type name
////////////////////////////////////////////////////////////////////////////////
static const char* TypeNameCapConstraint (TRI_index_t const* idx) {
return "cap";
}
////////////////////////////////////////////////////////////////////////////////
/// @brief describes a cap constraint as a json object
////////////////////////////////////////////////////////////////////////////////
static TRI_json_t* JsonCapConstraint (TRI_index_t* idx,
TRI_primary_collection_t const* primary) {
TRI_json_t* json;
TRI_cap_constraint_t* cap;
// recast as a cap constraint
cap = (TRI_cap_constraint_t*) idx;
// create json object and fill it
json = TRI_JsonIndex(TRI_CORE_MEM_ZONE, idx);
TRI_Insert3ArrayJson(TRI_CORE_MEM_ZONE, json, "size", TRI_CreateNumberJson(TRI_CORE_MEM_ZONE, cap->_count));
TRI_Insert3ArrayJson(TRI_CORE_MEM_ZONE, json, "byteSize", TRI_CreateNumberJson(TRI_CORE_MEM_ZONE, cap->_size));
return json;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes a cap constraint from collection
////////////////////////////////////////////////////////////////////////////////
static void RemoveIndexCapConstraint (TRI_index_t* idx,
TRI_primary_collection_t* primary) {
primary->_capConstraint = NULL;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief inserts a document
////////////////////////////////////////////////////////////////////////////////
static int InsertCapConstraint (TRI_index_t* idx,
TRI_doc_mptr_t const* doc,
const bool isRollback) {
TRI_cap_constraint_t* cap;
cap = (TRI_cap_constraint_t*) idx;
if (cap->_size > 0) {
// there is a size restriction
TRI_df_marker_t* marker;
marker = (TRI_df_marker_t*) doc->_data;
// check if the document would be too big
if ((int64_t) marker->_size > (int64_t) cap->_size) {
return TRI_ERROR_ARANGO_DOCUMENT_TOO_LARGE;
}
}
return TRI_ERROR_NO_ERROR;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief post processing of insert
////////////////////////////////////////////////////////////////////////////////
static int PostInsertCapConstraint (TRI_transaction_collection_t* trxCollection,
TRI_index_t* idx,
TRI_doc_mptr_t const* doc) {
TRI_cap_constraint_t* cap;
cap = (TRI_cap_constraint_t*) idx;
TRI_ASSERT_MAINTAINER(cap->_count > 0 || cap->_size > 0);
return ApplyCap(cap, trxCollection->_collection->_collection, trxCollection);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes a document
////////////////////////////////////////////////////////////////////////////////
static int RemoveCapConstraint (TRI_index_t* idx,
TRI_doc_mptr_t const* doc,
const bool isRollback) {
return TRI_ERROR_NO_ERROR;
}
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup VocBase
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a cap constraint
////////////////////////////////////////////////////////////////////////////////
TRI_index_t* TRI_CreateCapConstraint (struct TRI_primary_collection_s* primary,
size_t count,
int64_t size) {
TRI_cap_constraint_t* cap;
TRI_index_t* idx;
cap = TRI_Allocate(TRI_CORE_MEM_ZONE, sizeof(TRI_cap_constraint_t), false);
if (cap == NULL) {
return NULL;
}
idx = &cap->base;
idx->typeName = TypeNameCapConstraint;
TRI_InitIndex(idx, TRI_IDX_TYPE_CAP_CONSTRAINT, primary, false, true);
idx->json = JsonCapConstraint;
idx->removeIndex = RemoveIndexCapConstraint;
idx->insert = InsertCapConstraint;
idx->postInsert = PostInsertCapConstraint;
idx->remove = RemoveCapConstraint;
cap->_count = count;
cap->_size = size;
InitialiseCap(cap, primary);
return idx;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief frees the memory allocated, but does not free the pointer
////////////////////////////////////////////////////////////////////////////////
void TRI_DestroyCapConstraint (TRI_index_t* idx) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief frees the memory allocated and frees the pointer
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeCapConstraint (TRI_index_t* idx) {
TRI_DestroyCapConstraint(idx);
TRI_Free(TRI_CORE_MEM_ZONE, idx);
}
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- END-OF-FILE
// -----------------------------------------------------------------------------
// Local Variables:
// mode: outline-minor
// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|/// @page\\|// --SECTION--\\|/// @\\}"
// End: