//////////////////////////////////////////////////////////////////////////////// /// @brief AST query declarations /// /// @file /// /// DISCLAIMER /// /// Copyright 2010-2012 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 Jan Steemann /// @author Copyright 2012, triagens GmbH, Cologne, Germany //////////////////////////////////////////////////////////////////////////////// #include "QL/ast-query.h" // ----------------------------------------------------------------------------- // --SECTION-- private functions // ----------------------------------------------------------------------------- //////////////////////////////////////////////////////////////////////////////// /// @addtogroup QL /// @{ //////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////// /// @brief Hash function used to hash collection aliases //////////////////////////////////////////////////////////////////////////////// static uint64_t HashKey (TRI_associative_pointer_t* array, void const* key) { char const* k = (char const*) key; return TRI_FnvHashString(k); } //////////////////////////////////////////////////////////////////////////////// /// @brief Hash function used to hash elements in the collection //////////////////////////////////////////////////////////////////////////////// static uint64_t HashElement (TRI_associative_pointer_t* array, void const* element) { QL_ast_query_collection_t *collection = (QL_ast_query_collection_t*) element; return TRI_FnvHashString(collection->_alias); } //////////////////////////////////////////////////////////////////////////////// /// @brief Comparison function used to determine hash key equality //////////////////////////////////////////////////////////////////////////////// static bool EqualKeyElement (TRI_associative_pointer_t* array, void const* key, void const* element) { char const* k = (char const*) key; QL_ast_query_collection_t *collection = (QL_ast_query_collection_t*) element; return TRI_EqualString(k, collection->_alias); } //////////////////////////////////////////////////////////////////////////////// /// @} //////////////////////////////////////////////////////////////////////////////// // ----------------------------------------------------------------------------- // --SECTION-- public functions // ----------------------------------------------------------------------------- //////////////////////////////////////////////////////////////////////////////// /// @addtogroup QL /// @{ //////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////// /// @brief Initialize data structures for a query //////////////////////////////////////////////////////////////////////////////// void QLAstQueryInit (const TRI_vocbase_t* vocbase, QL_ast_query_t* query) { query->_vocbase = vocbase; query->_type = QLQueryTypeUndefined; query->_from._base = 0; query->_where._base = 0; query->_order._base = 0; query->_limit._isUsed = false; TRI_InitAssociativePointer(&query->_from._collections, HashKey, HashElement, EqualKeyElement, 0); } //////////////////////////////////////////////////////////////////////////////// /// @brief De-allocate data structures for a query //////////////////////////////////////////////////////////////////////////////// void QLAstQueryFree (QL_ast_query_t* query) { size_t i; void* ptr; // destroy all elements in collection array for (i = 0; i < query->_from._collections._nrAlloc; i++) { ptr = query->_from._collections._table[i]; if (ptr != 0) { TRI_Free(ptr); } } // destroy array itself TRI_DestroyAssociativePointer(&query->_from._collections); } //////////////////////////////////////////////////////////////////////////////// /// @brief get the ref count for a collection //////////////////////////////////////////////////////////////////////////////// size_t QLAstQueryGetRefCount (QL_ast_query_t* query, const char* alias) { QL_ast_query_collection_t* collection = (QL_ast_query_collection_t*) TRI_LookupByKeyAssociativePointer(&query->_from._collections, alias); if (collection != 0) { return collection->_refCount; } // return a number > 0 if collection not found so nothing happens with it return 1; } //////////////////////////////////////////////////////////////////////////////// /// @brief Increment ref count for a collection //////////////////////////////////////////////////////////////////////////////// void QLAstQueryAddRefCount (QL_ast_query_t* query, const char* alias) { QL_ast_query_collection_t* collection = (QL_ast_query_collection_t*) TRI_LookupByKeyAssociativePointer(&query->_from._collections, alias); if (collection != 0) { ++collection->_refCount; } } //////////////////////////////////////////////////////////////////////////////// /// @brief Check if a collection was defined in a query //////////////////////////////////////////////////////////////////////////////// bool QLAstQueryIsValidAlias (QL_ast_query_t* query, const char* alias) { return (0 != TRI_LookupByKeyAssociativePointer(&query->_from._collections, alias)); } //////////////////////////////////////////////////////////////////////////////// /// @brief Return the collection name for its alias //////////////////////////////////////////////////////////////////////////////// char* QLAstQueryGetCollectionNameForAlias (QL_ast_query_t* query, const char* alias) { QL_ast_query_collection_t* collection; collection = (QL_ast_query_collection_t*) TRI_LookupByKeyAssociativePointer(&query->_from._collections, alias); if (!collection) { return NULL; } return collection->_name; } //////////////////////////////////////////////////////////////////////////////// /// @brief Add a collection to the query //////////////////////////////////////////////////////////////////////////////// bool QLAstQueryAddCollection (QL_ast_query_t* query, const char* name, const char* alias) { QL_ast_query_collection_t* collection; QL_ast_query_collection_t* previous; previous = (QL_ast_query_collection_t*) TRI_LookupByKeyAssociativePointer (&query->_from._collections, alias); if (previous != 0) { // element is already present - return an error return false; } collection = (QL_ast_query_collection_t *) TRI_Allocate(sizeof(QL_ast_query_collection_t)); if (collection == 0) { return false; } collection->_name = (char*) name; collection->_alias = (char*) alias; // first collection added is always the primary collection collection->_isPrimary = (&query->_from._collections._nrUsed == 0); collection->_refCount = 0; // will be used later when optimizing joins TRI_InsertKeyAssociativePointer(&query->_from._collections, collection->_alias, collection, true); return true; } //////////////////////////////////////////////////////////////////////////////// /// @brief get the alias of the primary collection used in the query //////////////////////////////////////////////////////////////////////////////// char* QLAstQueryGetPrimaryAlias (const QL_ast_query_t* query) { size_t i; QL_ast_query_collection_t *collection; for (i = 0; i < query->_from._collections._nrAlloc; i++) { collection = query->_from._collections._table[i]; if (collection != 0 && collection->_isPrimary) { return collection->_alias; } } return 0; } //////////////////////////////////////////////////////////////////////////////// /// @} //////////////////////////////////////////////////////////////////////////////// // Local Variables: // mode: outline-minor // outline-regexp: "^\\(/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|// --SECTION--\\|/// @\\}\\)" // End: