minetest/src/database-postgresql.cpp
2016-05-22 11:34:47 +02:00

287 lines
6.7 KiB
C++

/*
Copyright (C) 2016 Loic Blot <loic.blot@unix-experience.fr>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#if USE_POSTGRESQL
#include "database-postgresql.h"
#ifdef _WIN32
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
// Without this some of the network functions are not found on mingw
#ifndef _WIN32_WINNT
#define _WIN32_WINNT 0x0501
#endif
#include <windows.h>
#include <winsock2.h>
#else
#include <netinet/in.h>
#endif
#include "log.h"
#include "exceptions.h"
#include "settings.h"
Database_PostgreSQL::Database_PostgreSQL(const Settings &conf) :
m_connect_string(""),
m_conn(NULL),
m_pgversion(0)
{
if (!conf.getNoEx("pgsql_connection", m_connect_string)) {
throw SettingNotFoundException(
"Set pgsql_connection string in world.mt to "
"use the postgresql backend\n"
"Notes:\n"
"pgsql_connection has the following form: \n"
"\tpgsql_connection = host=127.0.0.1 port=5432 user=mt_user "
"password=mt_password dbname=minetest_world\n"
"mt_user should have CREATE TABLE, INSERT, SELECT, UPDATE and "
"DELETE rights on the database.\n"
"Don't create mt_user as a SUPERUSER!");
}
connectToDatabase();
}
Database_PostgreSQL::~Database_PostgreSQL()
{
PQfinish(m_conn);
}
void Database_PostgreSQL::connectToDatabase()
{
m_conn = PQconnectdb(m_connect_string.c_str());
if (PQstatus(m_conn) != CONNECTION_OK) {
throw DatabaseException(std::string(
"PostgreSQL database error: ") +
PQerrorMessage(m_conn));
}
m_pgversion = PQserverVersion(m_conn);
/*
* We are using UPSERT feature from PostgreSQL 9.5
* to have the better performance,
* set the minimum version to 90500
*/
if (m_pgversion < 90500) {
throw DatabaseException("PostgreSQL database error: "
"Server version 9.5 or greater required.");
}
infostream << "PostgreSQL Database: Version " << m_pgversion
<< " Connection made." << std::endl;
createDatabase();
initStatements();
}
void Database_PostgreSQL::verifyDatabase()
{
if (PQstatus(m_conn) == CONNECTION_OK)
return;
PQreset(m_conn);
ping();
}
void Database_PostgreSQL::ping()
{
if (PQping(m_connect_string.c_str()) != PQPING_OK) {
throw DatabaseException(std::string(
"PostgreSQL database error: ") +
PQerrorMessage(m_conn));
}
}
bool Database_PostgreSQL::initialized() const
{
return (PQstatus(m_conn) == CONNECTION_OK);
}
void Database_PostgreSQL::initStatements()
{
prepareStatement("read_block",
"SELECT data FROM blocks "
"WHERE posX = $1::int4 AND posY = $2::int4 AND "
"posZ = $3::int4");
prepareStatement("write_block",
"INSERT INTO blocks (posX, posY, posZ, data) VALUES "
"($1::int4, $2::int4, $3::int4, $4::bytea) "
"ON CONFLICT ON CONSTRAINT blocks_pkey DO "
"UPDATE SET data = $4::bytea");
prepareStatement("delete_block", "DELETE FROM blocks WHERE "
"posX = $1::int4 AND posY = $2::int4 AND posZ = $3::int4");
prepareStatement("list_all_loadable_blocks",
"SELECT posX, posY, posZ FROM blocks");
}
PGresult *Database_PostgreSQL::checkResults(PGresult *result, bool clear)
{
ExecStatusType statusType = PQresultStatus(result);
switch (statusType) {
case PGRES_COMMAND_OK:
case PGRES_TUPLES_OK:
break;
case PGRES_FATAL_ERROR:
default:
throw DatabaseException(
std::string("PostgreSQL database error: ") +
PQresultErrorMessage(result));
}
if (clear)
PQclear(result);
return result;
}
void Database_PostgreSQL::createDatabase()
{
PGresult *result = checkResults(PQexec(m_conn,
"SELECT relname FROM pg_class WHERE relname='blocks';"),
false);
// If table doesn't exist, create it
if (!PQntuples(result)) {
static const char* dbcreate_sql = "CREATE TABLE blocks ("
"posX INT NOT NULL,"
"posY INT NOT NULL,"
"posZ INT NOT NULL,"
"data BYTEA,"
"PRIMARY KEY (posX,posY,posZ)"
");";
checkResults(PQexec(m_conn, dbcreate_sql));
}
PQclear(result);
infostream << "PostgreSQL: Game Database was inited." << std::endl;
}
void Database_PostgreSQL::beginSave()
{
verifyDatabase();
checkResults(PQexec(m_conn, "BEGIN;"));
}
void Database_PostgreSQL::endSave()
{
checkResults(PQexec(m_conn, "COMMIT;"));
}
bool Database_PostgreSQL::saveBlock(const v3s16 &pos,
const std::string &data)
{
// Verify if we don't overflow the platform integer with the mapblock size
if (data.size() > INT_MAX) {
errorstream << "Database_PostgreSQL::saveBlock: Data truncation! "
<< "data.size() over 0xFFFF (== " << data.size()
<< ")" << std::endl;
return false;
}
verifyDatabase();
s32 x, y, z;
x = htonl(pos.X);
y = htonl(pos.Y);
z = htonl(pos.Z);
const void *args[] = { &x, &y, &z, data.c_str() };
const int argLen[] = {
sizeof(x), sizeof(y), sizeof(z), (int)data.size()
};
const int argFmt[] = { 1, 1, 1, 1 };
execPrepared("write_block", ARRLEN(args), args, argLen, argFmt);
return true;
}
void Database_PostgreSQL::loadBlock(const v3s16 &pos,
std::string *block)
{
verifyDatabase();
s32 x, y, z;
x = htonl(pos.X);
y = htonl(pos.Y);
z = htonl(pos.Z);
const void *args[] = { &x, &y, &z };
const int argLen[] = { sizeof(x), sizeof(y), sizeof(z) };
const int argFmt[] = { 1, 1, 1 };
PGresult *results = execPrepared("read_block", ARRLEN(args), args,
argLen, argFmt, false);
*block = "";
if (PQntuples(results)) {
*block = std::string(PQgetvalue(results, 0, 0),
PQgetlength(results, 0, 0));
}
PQclear(results);
}
bool Database_PostgreSQL::deleteBlock(const v3s16 &pos)
{
verifyDatabase();
s32 x, y, z;
x = htonl(pos.X);
y = htonl(pos.Y);
z = htonl(pos.Z);
const void *args[] = { &x, &y, &z };
const int argLen[] = { sizeof(x), sizeof(y), sizeof(z) };
const int argFmt[] = { 1, 1, 1 };
execPrepared("read_block", ARRLEN(args), args, argLen, argFmt);
return true;
}
void Database_PostgreSQL::listAllLoadableBlocks(std::vector<v3s16> &dst)
{
verifyDatabase();
PGresult *results = execPrepared("list_all_loadable_blocks", 0,
NULL, NULL, NULL, false, false);
int numrows = PQntuples(results);
for (int row = 0; row < numrows; ++row) {
dst.push_back(pg_to_v3s16(results, 0, 0));
}
PQclear(results);
}
#endif // USE_POSTGRESQL