sqlite3_conn.go

// +build windows
// Copyright (C) 2016 Samuel Melrose <sam@infitialis.com>.
//
// Based on work by Yasuhiro Matsumoto <mattn.jp@gmail.com>
// https://github.com/mattn/go-sqlite3
//
// Use of this source code is governed by an MIT-style
// license that can be found in the LICENSE file.

package sqlite3

import (
	"database/sql/driver"
	"fmt"
	"runtime"
	"strings"

	"context"
)

// Exec implements Execer.
func (c *SQLiteConn) Exec(query string, args []driver.Value) (driver.Result, error) {
	list := make([]namedValue, len(args))
	for i, v := range args {
		list[i] = namedValue{
			Ordinal: i + 1,
			Value:   v,
		}
	}
	return c.exec(context.Background(), query, list)
}

func (c *SQLiteConn) exec(ctx context.Context, query string, args []namedValue) (driver.Result, error) {
	start := 0
	for {
		s, err := c.prepare(ctx, query)
		if err != nil {
			return nil, err
		}
		var res driver.Result
		if s.(*SQLiteStmt).s != sqlite3_stmt(uintptr(0)) {
			na := s.NumInput()
			if len(args) < na {
				return nil, fmt.Errorf("Not enough args to execute query. Expected %d, got %d.", na, len(args))
			}
			for i := 0; i < na; i++ {
				args[i].Ordinal -= start
			}
			res, err = s.(*SQLiteStmt).exec(ctx, args[:na])
			if err != nil && err != driver.ErrSkip {
				s.Close()
				return nil, err
			}
			args = args[na:]
			start += na
		}
		tail := s.(*SQLiteStmt).t
		s.Close()
		if tail == "" {
			return res, nil
		}
		query = tail
	}
}

// Query implements Queryer.
func (c *SQLiteConn) Query(query string, args []driver.Value) (driver.Rows, error) {
	list := make([]namedValue, len(args))
	for i, v := range args {
		list[i] = namedValue{
			Ordinal: i + 1,
			Value:   v,
		}
	}
	return c.query(context.Background(), query, list)
}

func (c *SQLiteConn) query(ctx context.Context, query string, args []namedValue) (driver.Rows, error) {
	start := 0
	for {
		s, err := c.prepare(ctx, query)
		if err != nil {
			return nil, err
		}
		s.(*SQLiteStmt).cls = true
		na := s.NumInput()
		if len(args) < na {
			return nil, fmt.Errorf("Not enough args to execute query. Expected %d, got %d.", na, len(args))
		}
		for i := 0; i < na; i++ {
			args[i].Ordinal -= start
		}
		rows, err := s.(*SQLiteStmt).query(ctx, args[:na])
		if err != nil && err != driver.ErrSkip {
			s.Close()
			return rows, err
		}
		args = args[na:]
		start += na
		tail := s.(*SQLiteStmt).t
		if tail == "" {
			return rows, nil
		}
		rows.Close()
		s.Close()
		query = tail
	}
}

// Begin transaction.
func (c *SQLiteConn) Begin() (driver.Tx, error) {
	return c.begin(context.Background())
}

func (c *SQLiteConn) begin(ctx context.Context) (driver.Tx, error) {
	if _, err := c.exec(ctx, c.txlock, nil); err != nil {
		return nil, err
	}
	return &SQLiteTx{c}, nil
}

// Prepare the query string. Return a new statement.
func (c *SQLiteConn) Prepare(query string) (driver.Stmt, error) {
	return c.prepare(context.Background(), query)
}

func (c *SQLiteConn) prepare(ctx context.Context, query string) (driver.Stmt, error) {
	rv, s, tail := sqlite3_prepare_v2(c.db, query)
	if rv != SQLITE_OK {
		return nil, c.lastError()
	}
	t := strings.TrimSpace(tail)
	ss := &SQLiteStmt{c: c, s: s, t: t}
	runtime.SetFinalizer(ss, (*SQLiteStmt).Close)
	return ss, nil
}

// AutoCommit return which currently auto commit or not.
func (c *SQLiteConn) AutoCommit() bool {
	return sqlite3_get_autocommit(c.db) != 0
}

// Close the connection.
func (c *SQLiteConn) Close() error {
	rv := sqlite3_close_v2(c.db)
	if rv != SQLITE_OK {
		return c.lastError()
	}
	c.db = sqlite3(uintptr(0))
	runtime.SetFinalizer(c, nil)
	return nil
}

func (c *SQLiteConn) lastError() Error {
	return Error{
		Code:         ErrNo(sqlite3_errcode(c.db)),
		ExtendedCode: ErrNoExtended(sqlite3_extended_errcode(c.db)),
		err:          sqlite3_errmsg(c.db),
	}
}