1
0
Fork 0
arangodb/VocBase/query-base.h

313 lines
13 KiB
C

////////////////////////////////////////////////////////////////////////////////
/// @brief Basic query data structures
///
/// @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
////////////////////////////////////////////////////////////////////////////////
#ifndef TRIAGENS_DURHAM_VOC_BASE_QUERY_BASE_H
#define TRIAGENS_DURHAM_VOC_BASE_QUERY_BASE_H 1
#include <BasicsC/common.h>
#include <BasicsC/vector.h>
#include <BasicsC/associative.h>
#include <BasicsC/strings.h>
#include <BasicsC/hashes.h>
#include <BasicsC/json.h>
#include <BasicsC/voc-errors.h>
#include "VocBase/vocbase.h"
#include "VocBase/query-node.h"
#include "QL/parser.h"
#include "QL/ast-query.h"
#ifdef __cplusplus
extern "C" {
#endif
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup VocBase
/// @{
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- query errors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief query error structure
///
/// This struct is used to hold information about errors that happen during
/// query execution. The data will be passed to the end user.
////////////////////////////////////////////////////////////////////////////////
typedef struct TRI_query_error_s {
int _code;
char* _message;
char* _data;
}
TRI_query_error_t;
// -----------------------------------------------------------------------------
// --SECTION-- locks
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- bind parameters
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief Query bind parameter
////////////////////////////////////////////////////////////////////////////////
typedef struct TRI_bind_parameter_s {
char* _name;
TRI_json_t* _data;
}
TRI_bind_parameter_t;
////////////////////////////////////////////////////////////////////////////////
/// @brief Get the names of all bind parameters
////////////////////////////////////////////////////////////////////////////////
TRI_vector_string_t TRI_GetNamesBindParameter (TRI_associative_pointer_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Free a bind parameter
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeBindParameter (TRI_bind_parameter_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Create a bind parameter
////////////////////////////////////////////////////////////////////////////////
TRI_bind_parameter_t* TRI_CreateBindParameter (const char*, const TRI_json_t*);
// -----------------------------------------------------------------------------
// --SECTION-- query template
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief lexer state
///
/// This struct contains the current lexer / scanner state. It contains
/// positioning information (pointer into query string, remaining length)
/// because flex processes strings in chunks of 8k by default.
///
/// Each lexer instance will have its own struct instance to support reentrancy.
////////////////////////////////////////////////////////////////////////////////
typedef struct TRI_query_parser_s {
void* _scanner;
char* _buffer;
int _length;
}
TRI_query_parser_t;
////////////////////////////////////////////////////////////////////////////////
/// @brief query template structure
///
/// A query template is a blueprint for a query execution. It is abstract in the
/// sense that it does not contain any bind parameter values and no result set.
/// A query instance (@ref TRI_query_instance_t) can be created from a query
/// template.
///
/// The template contains vectors that contain locations of allocated memory.
/// This is especially important because in case of parse errors, bison / flex
/// will not automatically free any allocated memory.
/// This has to be done manually, and that is what the vectors are used for.
/// There is a vector for AST nodes and a vector for strings
/// (used to keep track of string literals used in the query). There are also
/// two vectors to keep track of list elements (arrays / objects) in queries.
////////////////////////////////////////////////////////////////////////////////
typedef struct TRI_query_template_s {
TRI_vocbase_t* _vocbase;
char* _queryString;
QL_ast_query_t* _query;
TRI_query_parser_t* _parser;
TRI_mutex_t _lock;
bool _deleted;
struct {
TRI_vector_pointer_t _nodes; // memory locations of allocated AST nodes
TRI_vector_pointer_t _strings; // memory locations of allocated strings
TRI_vector_pointer_t _listHeads; // start of lists
TRI_vector_pointer_t _listTails; // end of lists
} _memory;
TRI_query_error_t _error;
TRI_associative_pointer_t _bindParameters;
}
TRI_query_template_t;
////////////////////////////////////////////////////////////////////////////////
/// @brief Initialize the structs contained in a query template and perform
/// some basic optimizations and type detections
////////////////////////////////////////////////////////////////////////////////
bool TRI_InitQueryTemplate (TRI_query_template_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Add a bind parameter to a query template
////////////////////////////////////////////////////////////////////////////////
bool TRI_AddBindParameterQueryTemplate (TRI_query_template_t* const,
const TRI_bind_parameter_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Create a query template
////////////////////////////////////////////////////////////////////////////////
TRI_query_template_t* TRI_CreateQueryTemplate (const char*,
const TRI_vocbase_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Free a query template
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeQueryTemplate (TRI_query_template_t*);
// -----------------------------------------------------------------------------
// --SECTION-- query instance
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief query instance structure
///
/// A query instance is a concrete query that has specific bind parameter values
/// and a specific result set
/// This struct is used to hold information about errors that happen during
/// query execution. The data will be passed to the end user.
////////////////////////////////////////////////////////////////////////////////
typedef struct TRI_query_instance_s {
TRI_query_template_t* _template;
bool _wasKilled;
bool _doAbort;
TRI_query_error_t _error;
TRI_associative_pointer_t _bindParameters;
QL_ast_query_t _query;
TRI_vector_pointer_t _join;
TRI_vector_pointer_t* _locks;
struct {
TRI_vector_pointer_t _nodes; // memory locations of allocated AST nodes
TRI_vector_pointer_t _strings; // memory locations of allocated strings
} _memory;
}
TRI_query_instance_t;
////////////////////////////////////////////////////////////////////////////////
/// @brief Set the value of a bind parameter
////////////////////////////////////////////////////////////////////////////////
bool TRI_AddBindParameterQueryInstance (TRI_query_instance_t* const,
const TRI_bind_parameter_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Free a query instance
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeQueryInstance (TRI_query_instance_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Create a query instance with bind parameters (may be empty)
////////////////////////////////////////////////////////////////////////////////
TRI_query_instance_t* TRI_CreateQueryInstance (const TRI_query_template_t* const,
const TRI_json_t*);
////////////////////////////////////////////////////////////////////////////////
/// @brief Kill a query instance
///
/// This will set a killed flag and register an error. It will not free the
/// query instance. This will be done by the query executor
////////////////////////////////////////////////////////////////////////////////
void TRI_KillQueryInstance (TRI_query_instance_t* const instance);
////////////////////////////////////////////////////////////////////////////////
/// @brief Register an error during query execution
////////////////////////////////////////////////////////////////////////////////
bool TRI_RegisterErrorQueryInstance (TRI_query_instance_t* const,
const int,
const char*);
////////////////////////////////////////////////////////////////////////////////
/// @brief Copy a part of the query's AST and insert bind parameter values on
/// the fly
////////////////////////////////////////////////////////////////////////////////
TRI_query_node_t* TRI_CopyQueryPartQueryInstance (TRI_query_instance_t* const,
const TRI_query_node_t* const);
// -----------------------------------------------------------------------------
// --SECTION-- errors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief Register an error
////////////////////////////////////////////////////////////////////////////////
void TRI_SetQueryError (TRI_query_error_t* const, const int, const char*);
////////////////////////////////////////////////////////////////////////////////
/// @brief Get the error code registered last
////////////////////////////////////////////////////////////////////////////////
int TRI_GetCodeQueryError (const TRI_query_error_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief Get the error string registered last
////////////////////////////////////////////////////////////////////////////////
char* TRI_GetStringQueryError (const TRI_query_error_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief initialize an error structure
////////////////////////////////////////////////////////////////////////////////
void TRI_InitQueryError (TRI_query_error_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @brief free an error structure
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeQueryError (TRI_query_error_t* const);
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
#ifdef __cplusplus
}
#endif
#endif
// Local Variables:
// mode: outline-minor
// outline-regexp: "^\\(/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|// --SECTION--\\|/// @\\}\\)"
// End: