DarkflameServer/thirdparty/raknet/Source/DS_Table.h

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#ifndef __TABLE_H
#define __TABLE_H
#ifdef _MSC_VER
#pragma warning( push )
#endif
#include "DS_List.h"
#include "DS_BPlusTree.h"
#include "RakMemoryOverride.h"
#include "Export.h"
#include "RakString.h"
#define _TABLE_BPLUS_TREE_ORDER 16
#define _TABLE_MAX_COLUMN_NAME_LENGTH 32
/// The namespace DataStructures was only added to avoid compiler errors for commonly named data structures
/// As these data structures are stand-alone, you can use them outside of RakNet for your own projects if you wish.
namespace DataStructures
{
/// \brief Holds a set of columns, a set of rows, and rows times columns cells.
/// The table data structure is useful if you want to store a set of structures and perform queries on those structures
/// This is a relatively simple and fast implementation of the types of tables commonly used in databases
/// See TableSerializer to serialize data members of the table
/// See LightweightDatabaseClient and LightweightDatabaseServer to transmit the table over the network.
class RAK_DLL_EXPORT Table : public RakNet::RakMemoryOverride
{
public:
enum ColumnType
{
// Cell::i used
NUMERIC,
// Cell::c used to hold a null terminated string.
STRING,
// Cell::c holds data. Cell::i holds data length of c in bytes.
BINARY,
// Cell::c holds data. Not deallocated. Set manually by assigning ptr.
POINTER,
};
/// Holds the actual data in the table
struct RAK_DLL_EXPORT Cell
{
Cell();
~Cell();
Cell(int intValue, char *charValue, void *ptr, ColumnType type);
void Clear(void);
/// Numeric
void Set(int input);
/// String
void Set(const char *input);
/// Binary
void Set(const char *input, int inputLength);
/// Pointer
void SetPtr(void* p);
/// Numeric
void Get(int *output);
/// String
void Get(char *output);
/// Binary
void Get(char *output, int *outputLength);
RakNet::RakString ToString(ColumnType columnType);
// assignment operator and copy constructor
Cell& operator = ( const Cell& input );
Cell( const Cell & input);
bool isEmpty;
int i;
char *c;
void *ptr;
};
/// Stores the name and type of the column
/// \internal
struct RAK_DLL_EXPORT ColumnDescriptor
{
ColumnDescriptor();
~ColumnDescriptor();
ColumnDescriptor(const char cn[_TABLE_MAX_COLUMN_NAME_LENGTH],ColumnType ct);
char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH];
ColumnType columnType;
};
/// Stores the list of cells for this row, and a special flag used for internal sorting
struct RAK_DLL_EXPORT Row
{
// list of cells
DataStructures::List<Cell*> cells;
/// Numeric
void UpdateCell(unsigned columnIndex, int value);
/// String
void UpdateCell(unsigned columnIndex, const char *str);
/// Binary
void UpdateCell(unsigned columnIndex, int byteLength, const char *data);
};
// Operations to perform for cell comparison
enum FilterQueryType
{
QF_EQUAL,
QF_NOT_EQUAL,
QF_GREATER_THAN,
QF_GREATER_THAN_EQ,
QF_LESS_THAN,
QF_LESS_THAN_EQ,
QF_IS_EMPTY,
QF_NOT_EMPTY,
};
// Compare the cell value for a row at columnName to the cellValue using operation.
struct RAK_DLL_EXPORT FilterQuery
{
FilterQuery();
~FilterQuery();
FilterQuery(unsigned column, Cell *cell, FilterQueryType op);
// If columnName is specified, columnIndex will be looked up using it.
char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH];
unsigned columnIndex;
Cell *cellValue;
FilterQueryType operation;
};
/// Increasing or decreasing sort order
enum SortQueryType
{
QS_INCREASING_ORDER,
QS_DECREASING_ORDER,
};
// Sort on increasing or decreasing order for a particular column
struct RAK_DLL_EXPORT SortQuery
{
/// The index of the table column we are sorting on
unsigned columnIndex;
/// See SortQueryType
SortQueryType operation;
};
/// Constructor
Table();
/// Destructor
~Table();
/// \brief Adds a column to the table
/// \param[in] columnName The name of the column
/// \param[in] columnType What type of data this column will hold
/// \return The index of the new column
unsigned AddColumn(const char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH], ColumnType columnType);
/// \brief Removes a column by index
/// \param[in] columnIndex The index of the column to remove
void RemoveColumn(unsigned columnIndex);
/// \brief Gets the index of a column by name
/// Column indices are stored in the order they are added.
/// \param[in] columnName The name of the column
/// \return The index of the column, or (unsigned)-1 if no such column
unsigned ColumnIndex(char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH]);
unsigned ColumnIndex(const char *columnName);
/// \brief Gives the string name of the column at a certain index
/// \param[in] index The index of the column
/// \return The name of the column, or 0 if an invalid index
char* ColumnName(unsigned index);
/// \brief Returns the type of a column, referenced by index
/// \param[in] index The index of the column
/// \return The type of the column
ColumnType GetColumnType(unsigned index);
/// Returns the number of columns
/// \return The number of columns in the table
unsigned GetColumnCount(void) const;
/// Returns the number of rows
/// \return The number of rows in the table
unsigned GetRowCount(void) const;
/// \brief Adds a row to the table
/// New rows are added with empty values for all cells. However, if you specify initialCelLValues you can specify initial values
/// It's up to you to ensure that the values in the specific cells match the type of data used by that row
/// rowId can be considered the primary key for the row. It is much faster to lookup a row by its rowId than by searching keys.
/// rowId must be unique
/// Rows are stored in sorted order in the table, using rowId as the sort key
/// \param[in] rowId The UNIQUE primary key for the row. This can never be changed.
/// \param[in] initialCellValues Initial values to give the row (optional)
/// \return The newly added row
Table::Row* AddRow(unsigned rowId);
Table::Row* AddRow(unsigned rowId, DataStructures::List<Cell> &initialCellValues);
/// Removes a row specified by rowId
/// \param[in] rowId The ID of the row
void RemoveRow(unsigned rowId);
/// Removes all the rows with IDs that the specified table also has
/// \param[in] tableContainingRowIDs The IDs of the rows
void RemoveRows(Table *tableContainingRowIDs);
/// Updates a particular cell in the table
/// \note If you are going to update many cells of a particular row, it is more efficient to call GetRow and perform the operations on the row directly.
/// \note Row pointers do not change, so you can also write directly to the rows for more efficiency.
/// \param[in] rowId The ID of the row
/// \param[in] columnIndex The column of the cell
/// \param[in] value The data to set
bool UpdateCell(unsigned rowId, unsigned columnIndex, int value);
bool UpdateCell(unsigned rowId, unsigned columnIndex, char *str);
bool UpdateCell(unsigned rowId, unsigned columnIndex, int byteLength, char *data);
bool UpdateCellByIndex(unsigned rowIndex, unsigned columnIndex, int value);
bool UpdateCellByIndex(unsigned rowIndex, unsigned columnIndex, char *str);
bool UpdateCellByIndex(unsigned rowIndex, unsigned columnIndex, int byteLength, char *data);
/// Note this is much less efficient to call than GetRow, then working with the cells directly
/// Numeric, string, binary
void GetCellValueByIndex(unsigned rowIndex, unsigned columnIndex, int *output);
void GetCellValueByIndex(unsigned rowIndex, unsigned columnIndex, char *output);
void GetCellValueByIndex(unsigned rowIndex, unsigned columnIndex, char *output, int *outputLength);
/// Gets a row. More efficient to do this and access Row::cells than to repeatedly call GetCell.
/// You can also update cells in rows from this function.
/// \param[in] rowId The ID of the row
/// \return The desired row, or 0 if no such row.
Row* GetRowByID(unsigned rowId) const;
/// Gets a row at a specific index
/// rowIndex should be less than GetRowCount()
/// \param[in] rowIndex The index of the row
/// \param[out] key The ID of the row returned
/// \return The desired row, or 0 if no such row.
Row* GetRowByIndex(unsigned rowIndex, unsigned *key) const;
/// \brief Queries the table, optionally returning only a subset of columns and rows.
/// \param[in] columnSubset An array of column indices. Only columns in this array are returned. Pass 0 for all columns
/// \param[in] numColumnSubset The number of elements in \a columnSubset
/// \param[in] inclusionFilters An array of FilterQuery. All filters must pass for the row to be returned.
/// \param[in] numInclusionFilters The number of elements in \a inclusionFilters
/// \param[in] rowIds An arrow of row IDs. Only these rows with these IDs are returned. Pass 0 for all rows.
/// \param[in] numRowIDs The number of elements in \a rowIds
/// \param[out] result The result of the query. If no rows are returned, the table will only have columns.
void QueryTable(unsigned *columnIndicesSubset, unsigned numColumnSubset, FilterQuery *inclusionFilters, unsigned numInclusionFilters, unsigned *rowIds, unsigned numRowIDs, Table *result);
/// \brief Sorts the table by rows
/// You can sort the table in ascending or descending order on one or more columns
/// Columns have precedence in the order they appear in the \a sortQueries array
/// If a row cell on column n has the same value as a a different row on column n, then the row will be compared on column n+1
/// \param[in] sortQueries A list of SortQuery structures, defining the sorts to perform on the table
/// \param[in] numColumnSubset The number of elements in \a numSortQueries
/// \param[out] out The address of an array of Rows, which will receive the sorted output. The array must be long enough to contain all returned rows, up to GetRowCount()
void SortTable(Table::SortQuery *sortQueries, unsigned numSortQueries, Table::Row** out);
/// Frees all memory in the table.
void Clear(void);
/// Prints out the names of all the columns
/// \param[out] out A pointer to an array of bytes which will hold the output.
/// \param[in] outLength The size of the \a out array
/// \param[in] columnDelineator What character to print to delineate columns
void PrintColumnHeaders(char *out, int outLength, char columnDelineator) const;
/// Writes a text representation of the row to \a out
/// \param[out] out A pointer to an array of bytes which will hold the output.
/// \param[in] outLength The size of the \a out array
/// \param[in] columnDelineator What character to print to delineate columns
/// \param[in] printDelineatorForBinary Binary output is not printed. True to still print the delineator.
/// \param[in] inputRow The row to print
void PrintRow(char *out, int outLength, char columnDelineator, bool printDelineatorForBinary, Table::Row* inputRow) const;
/// Direct access to make things easier
DataStructures::List<ColumnDescriptor>& GetColumns(void);
/// Direct access to make things easier
DataStructures::BPlusTree<unsigned, Row*, _TABLE_BPLUS_TREE_ORDER>& GetRows(void);
/// Get the head of a linked list containing all the row data
DataStructures::Page<unsigned, DataStructures::Table::Row*, _TABLE_BPLUS_TREE_ORDER> * GetListHead(void);
/// Get the first free row id.
/// This could be made more efficient.
unsigned GetAvailableRowId(void) const;
protected:
Table::Row* AddRowColumns(unsigned rowId, Row *row, DataStructures::List<unsigned> columnIndices);
void DeleteRow(Row *row);
void QueryRow(DataStructures::List<unsigned> &inclusionFilterColumnIndices, DataStructures::List<unsigned> &columnIndicesToReturn, unsigned key, Table::Row* row, FilterQuery *inclusionFilters, Table *result);
// 16 is arbitrary and is the order of the BPlus tree. Higher orders are better for searching while lower orders are better for
// Insertions and deletions.
DataStructures::BPlusTree<unsigned, Row*, _TABLE_BPLUS_TREE_ORDER> rows;
// Columns in the table.
DataStructures::List<ColumnDescriptor> columns;
};
}
#ifdef _MSC_VER
#pragma warning( pop )
#endif
#endif