lbcwallet/walletdb/bdb/driver.go

/*
 * Copyright (c) 2014 Conformal Systems LLC <info@conformal.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

package bdb

import (
	"fmt"

	"github.com/btcsuite/btcwallet/walletdb"
)

const (
	dbType = "bdb"
)

// parseArgs parses the arguments from the walletdb Open/Create methods.
func parseArgs(funcName string, args ...interface{}) (string, error) {
	if len(args) != 1 {
		return "", fmt.Errorf("invalid arguments to %s.%s -- "+
			"expected database path", dbType, funcName)
	}

	dbPath, ok := args[0].(string)
	if !ok {
		return "", fmt.Errorf("first argument to %s.%s is invalid -- "+
			"expected database path string", dbType, funcName)
	}

	return dbPath, nil
}

// openDBDriver is the callback provided during driver registration that opens
// an existing database for use.
func openDBDriver(args ...interface{}) (walletdb.DB, error) {
	dbPath, err := parseArgs("Open", args...)
	if err != nil {
		return nil, err
	}

	return openDB(dbPath, false)
}

// createDBDriver is the callback provided during driver registration that
// creates, initializes, and opens a database for use.
func createDBDriver(args ...interface{}) (walletdb.DB, error) {
	dbPath, err := parseArgs("Create", args...)
	if err != nil {
		return nil, err
	}

	return openDB(dbPath, true)
}

func init() {
	// Register the driver.
	driver := walletdb.Driver{
		DbType: dbType,
		Create: createDBDriver,
		Open:   openDBDriver,
	}
	if err := walletdb.RegisterDriver(driver); err != nil {
		panic(fmt.Sprintf("Failed to regiser database driver '%s': %v",
			dbType, err))
	}
}