connection.go

/*******************************************************************************
The MIT License (MIT)

Copyright (c) 2013-2019 Hajime Nakagami

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*******************************************************************************/

package firebirdsql

import (
	"context"
	"database/sql/driver"
	"math/big"
)

type firebirdsqlConn struct {
	wp                *wireProtocol
	tx                *firebirdsqlTx
	dsn               *firebirdDsn
	columnNameToLower bool
	isAutocommit      bool
	clientPublic      *big.Int
	clientSecret      *big.Int
	transactionSet    map[*firebirdsqlTx]struct{}
}

// ============ driver.Conn implementation

func (fc *firebirdsqlConn) begin(isolationLevel int) (driver.Tx, error) {
	tx, err := newFirebirdsqlTx(fc, isolationLevel, false, true)
	fc.tx = tx
	return driver.Tx(tx), err
}

// Begin starts and returns a new transaction.
//
// Deprecated: Drivers should implement ConnBeginTx instead (or additionally).
// -> is implemented in driver_go18.go with BeginTx()
func (fc *firebirdsqlConn) Begin() (driver.Tx, error) {
	return fc.begin(ISOLATION_LEVEL_READ_COMMITED)
}

// Close invalidates and potentially stops any current
// prepared statements and transactions, marking this
// connection as no longer in use.
//
// Because the sql package maintains a free pool of
// connections and only calls Close when there's a surplus of
// idle connections, it shouldn't be necessary for drivers to
// do their own connection caching.
func (fc *firebirdsqlConn) Close() (err error) {
	for tx := range fc.transactionSet {
		tx.Rollback()
	}

	err = fc.wp.opDetach()
	if err != nil {
		return
	}
	_, _, _, err = fc.wp.opResponse()
	fc.wp.conn.Close()
	return
}

func (fc *firebirdsqlConn) prepare(ctx context.Context, query string) (driver.Stmt, error) {
	if fc.tx.needBegin {
		err := fc.tx.begin()
		if err != nil {
			return nil, err
		}
	}

	return newFirebirdsqlStmt(fc, query)
}

// Prepare returns a prepared statement, bound to this connection.
func (fc *firebirdsqlConn) Prepare(query string) (driver.Stmt, error) {
	return fc.prepare(context.Background(), query)
}

// ============ driver.Tx implementation

func (fc *firebirdsqlConn) exec(ctx context.Context, query string, args []driver.Value) (result driver.Result, err error) {

	stmt, err := fc.prepare(ctx, query)
	if err != nil {
		return
	}

	result, err = stmt.(*firebirdsqlStmt).exec(ctx, args)
	if err != nil {
		return
	}

	stmt.Close()

	return
}

func (fc *firebirdsqlConn) Exec(query string, args []driver.Value) (result driver.Result, err error) {
	return fc.exec(context.Background(), query, args)
}

func (fc *firebirdsqlConn) query(ctx context.Context, query string, args []driver.Value) (rows driver.Rows, err error) {

	stmt, err := fc.prepare(ctx, query)
	if err != nil {
		return
	}
	rows, err = stmt.(*firebirdsqlStmt).query(ctx, args)
	return
}

func (fc *firebirdsqlConn) Query(query string, args []driver.Value) (rows driver.Rows, err error) {
	return fc.query(context.Background(), query, args)
}

func newFirebirdsqlConn(dsn *firebirdDsn) (fc *firebirdsqlConn, err error) {

	wp, err := newWireProtocol(dsn.addr, dsn.options["timezone"], dsn.options["charset"])
	if err != nil {
		return
	}

	column_name_to_lower := convertToBool(dsn.options["column_name_to_lower"], false)

	clientPublic, clientSecret := getClientSeed()

	err = wp.opConnect(dsn.dbName, dsn.user, dsn.passwd, dsn.options, clientPublic)
	if err != nil {
		return
	}

	err = wp._parse_connect_response(dsn.user, dsn.passwd, dsn.options, clientPublic, clientSecret)
	if err != nil {
		return
	}

	err = wp.opAttach(dsn.dbName, dsn.user, dsn.passwd, dsn.options["role"])
	if err != nil {
		return
	}

	wp.dbHandle, _, _, err = wp.opResponse()
	if err != nil {
		return
	}

	fc = new(firebirdsqlConn)
	fc.transactionSet = make(map[*firebirdsqlTx]struct{})
	fc.wp = wp
	fc.dsn = dsn
	fc.columnNameToLower = column_name_to_lower
	fc.isAutocommit = true
	fc.tx, err = newFirebirdsqlTx(fc, ISOLATION_LEVEL_READ_COMMITED, fc.isAutocommit, false)
	fc.clientPublic = clientPublic
	fc.clientSecret = clientSecret

	return fc, err
}

func createFirebirdsqlConn(dsn *firebirdDsn) (fc *firebirdsqlConn, err error) {

	wp, err := newWireProtocol(dsn.addr, dsn.options["timezone"], dsn.options["charset"])
	if err != nil {
		return
	}
	column_name_to_lower := convertToBool(dsn.options["column_name_to_lower"], false)

	clientPublic, clientSecret := getClientSeed()

	err = wp.opConnect(dsn.dbName, dsn.user, dsn.passwd, dsn.options, clientPublic)
	if err != nil {
		return
	}

	err = wp._parse_connect_response(dsn.user, dsn.passwd, dsn.options, clientPublic, clientSecret)
	if err != nil {
		return
	}

	err = wp.opCreate(dsn.dbName, dsn.user, dsn.passwd, dsn.options["role"])
	if err != nil {
		return
	}

	wp.dbHandle, _, _, err = wp.opResponse()
	if err != nil {
		return
	}

	fc = new(firebirdsqlConn)
	fc.transactionSet = make(map[*firebirdsqlTx]struct{})
	fc.wp = wp
	fc.dsn = dsn
	fc.columnNameToLower = column_name_to_lower
	fc.isAutocommit = true
	fc.tx, err = newFirebirdsqlTx(fc, ISOLATION_LEVEL_READ_COMMITED, fc.isAutocommit, false)
	fc.clientPublic = clientPublic
	fc.clientSecret = clientSecret

	return fc, err
}