src/Database/Database.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2020, Friendica
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Database;
  23
  24 use Friendica\Core\Config\Cache;
  25 use Friendica\Core\System;
  26 use Friendica\Network\HTTPException\InternalServerErrorException;
  27 use Friendica\Util\DateTimeFormat;
  28 use Friendica\Util\Profiler;
  29 use mysqli;
  30 use mysqli_result;
  31 use mysqli_stmt;
  32 use PDO;
  33 use PDOException;
  34 use PDOStatement;
  35 use Psr\Log\LoggerInterface;
  36
  37 /**
  38  * This class is for the low level database stuff that does driver specific things.
  39  */
  40 class Database
  41 {
  42         const PDO = 'pdo';
  43         const MYSQLI = 'mysqli';
  44
  45         protected $connected = false;
  46
  47         /**
  48          * @var Cache
  49          */
  50         protected $configCache;
  51         /**
  52          * @var Profiler
  53          */
  54         protected $profiler;
  55         /**
  56          * @var LoggerInterface
  57          */
  58         protected $logger;
  59         protected $server_info    = '';
  60         /** @var PDO|mysqli */
  61         protected $connection;
  62         protected $driver;
  63         protected $emulate_prepares = false;
  64         protected $pdo_emulate_prepares = false;
  65         private $error          = false;
  66         private $errorno        = 0;
  67         private $affected_rows  = 0;
  68         protected $in_transaction = false;
  69         protected $in_retrial     = false;
  70         protected $testmode       = false;
  71         private $relation       = [];
  72
  73         public function __construct(Cache $configCache, Profiler $profiler, LoggerInterface $logger)
  74         {
  75                 // We are storing these values for being able to perform a reconnect
  76                 $this->configCache   = $configCache;
  77                 $this->profiler      = $profiler;
  78                 $this->logger        = $logger;
  79
  80                 $this->connect();
  81
  82                 if ($this->isConnected()) {
  83                         // Loads DB_UPDATE_VERSION constant
  84                         DBStructure::definition($configCache->get('system', 'basepath'), false);
  85                 }
  86         }
  87
  88         public function connect()
  89         {
  90                 if (!is_null($this->connection) && $this->connected()) {
  91                         return $this->connected;
  92                 }
  93
  94                 // Reset connected state
  95                 $this->connected = false;
  96
  97                 $port       = 0;
  98                 $serveraddr = trim($this->configCache->get('database', 'hostname'));
  99                 $serverdata = explode(':', $serveraddr);
 100                 $server     = $serverdata[0];
 101                 if (count($serverdata) > 1) {
 102                         $port = trim($serverdata[1]);
 103                 }
 104
 105                 if (!empty(trim($this->configCache->get('database', 'port')))) {
 106                         $port = trim($this->configCache->get('database', 'port'));
 107                 }
 108
 109                 $server  = trim($server);
 110                 $user    = trim($this->configCache->get('database', 'username'));
 111                 $pass    = trim($this->configCache->get('database', 'password'));
 112                 $db      = trim($this->configCache->get('database', 'database'));
 113                 $charset = trim($this->configCache->get('database', 'charset'));
 114
 115                 if (!(strlen($server) && strlen($user))) {
 116                         return false;
 117                 }
 118
 119                 $persistent = (bool)$this->configCache->get('database', 'persistent');
 120
 121                 $this->emulate_prepares = (bool)$this->configCache->get('database', 'emulate_prepares');
 122                 $this->pdo_emulate_prepares = (bool)$this->configCache->get('database', 'pdo_emulate_prepares');
 123
 124                 if (!$this->configCache->get('database', 'disable_pdo') && class_exists('\PDO') && in_array('mysql', PDO::getAvailableDrivers())) {
 125                         $this->driver = self::PDO;
 126                         $connect      = "mysql:host=" . $server . ";dbname=" . $db;
 127
 128                         if ($port > 0) {
 129                                 $connect .= ";port=" . $port;
 130                         }
 131
 132                         if ($charset) {
 133                                 $connect .= ";charset=" . $charset;
 134                         }
 135
 136                         try {
 137                                 $this->connection = @new PDO($connect, $user, $pass, [PDO::ATTR_PERSISTENT => $persistent]);
 138                                 $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->pdo_emulate_prepares);
 139                                 $this->connected = true;
 140                         } catch (PDOException $e) {
 141                                 $this->connected = false;
 142                         }
 143                 }
 144
 145                 if (!$this->connected && class_exists('\mysqli')) {
 146                         $this->driver = self::MYSQLI;
 147
 148                         if ($port > 0) {
 149                                 $this->connection = @new mysqli($server, $user, $pass, $db, $port);
 150                         } else {
 151                                 $this->connection = @new mysqli($server, $user, $pass, $db);
 152                         }
 153
 154                         if (!mysqli_connect_errno()) {
 155                                 $this->connected = true;
 156
 157                                 if ($charset) {
 158                                         $this->connection->set_charset($charset);
 159                                 }
 160                         }
 161                 }
 162
 163                 // No suitable SQL driver was found.
 164                 if (!$this->connected) {
 165                         $this->driver     = null;
 166                         $this->connection = null;
 167                 }
 168
 169                 return $this->connected;
 170         }
 171
 172         public function setTestmode(bool $test)
 173         {
 174                 $this->testmode = $test;
 175         }
 176         /**
 177          * Sets the logger for DBA
 178          *
 179          * @note this is necessary because if we want to load the logger configuration
 180          *       from the DB, but there's an error, we would print out an exception.
 181          *       So the logger gets updated after the logger configuration can be retrieved
 182          *       from the database
 183          *
 184          * @param LoggerInterface $logger
 185          */
 186         public function setLogger(LoggerInterface $logger)
 187         {
 188                 $this->logger = $logger;
 189         }
 190
 191         /**
 192          * Sets the profiler for DBA
 193          *
 194          * @param Profiler $profiler
 195          */
 196         public function setProfiler(Profiler $profiler)
 197         {
 198                 $this->profiler = $profiler;
 199         }
 200         /**
 201          * Disconnects the current database connection
 202          */
 203         public function disconnect()
 204         {
 205                 if (!is_null($this->connection)) {
 206                         switch ($this->driver) {
 207                                 case self::PDO:
 208                                         $this->connection = null;
 209                                         break;
 210                                 case self::MYSQLI:
 211                                         $this->connection->close();
 212                                         $this->connection = null;
 213                                         break;
 214                         }
 215                 }
 216
 217                 $this->driver    = null;
 218                 $this->connected = false;
 219         }
 220
 221         /**
 222          * Perform a reconnect of an existing database connection
 223          */
 224         public function reconnect()
 225         {
 226                 $this->disconnect();
 227                 return $this->connect();
 228         }
 229
 230         /**
 231          * Return the database object.
 232          *
 233          * @return PDO|mysqli
 234          */
 235         public function getConnection()
 236         {
 237                 return $this->connection;
 238         }
 239
 240         /**
 241          * Return the database driver string
 242          *
 243          * @return string with either "pdo" or "mysqli"
 244          */
 245         public function getDriver()
 246         {
 247                 return $this->driver;
 248         }
 249
 250         /**
 251          * Returns the MySQL server version string
 252          *
 253          * This function discriminate between the deprecated mysql API and the current
 254          * object-oriented mysqli API. Example of returned string: 5.5.46-0+deb8u1
 255          *
 256          * @return string
 257          */
 258         public function serverInfo()
 259         {
 260                 if ($this->server_info == '') {
 261                         switch ($this->driver) {
 262                                 case self::PDO:
 263                                         $this->server_info = $this->connection->getAttribute(PDO::ATTR_SERVER_VERSION);
 264                                         break;
 265                                 case self::MYSQLI:
 266                                         $this->server_info = $this->connection->server_info;
 267                                         break;
 268                         }
 269                 }
 270                 return $this->server_info;
 271         }
 272
 273         /**
 274          * Returns the selected database name
 275          *
 276          * @return string
 277          * @throws \Exception
 278          */
 279         public function databaseName()
 280         {
 281                 $ret  = $this->p("SELECT DATABASE() AS `db`");
 282                 $data = $this->toArray($ret);
 283                 return $data[0]['db'];
 284         }
 285
 286         /**
 287          * Analyze a database query and log this if some conditions are met.
 288          *
 289          * @param string $query The database query that will be analyzed
 290          *
 291          * @throws \Exception
 292          */
 293         private function logIndex($query)
 294         {
 295
 296                 if (!$this->configCache->get('system', 'db_log_index')) {
 297                         return;
 298                 }
 299
 300                 // Don't explain an explain statement
 301                 if (strtolower(substr($query, 0, 7)) == "explain") {
 302                         return;
 303                 }
 304
 305                 // Only do the explain on "select", "update" and "delete"
 306                 if (!in_array(strtolower(substr($query, 0, 6)), ["select", "update", "delete"])) {
 307                         return;
 308                 }
 309
 310                 $r = $this->p("EXPLAIN " . $query);
 311                 if (!$this->isResult($r)) {
 312                         return;
 313                 }
 314
 315                 $watchlist = explode(',', $this->configCache->get('system', 'db_log_index_watch'));
 316                 $denylist = explode(',', $this->configCache->get('system', 'db_log_index_denylist'));
 317
 318                 while ($row = $this->fetch($r)) {
 319                         if ((intval($this->configCache->get('system', 'db_loglimit_index')) > 0)) {
 320                                 $log = (in_array($row['key'], $watchlist) &&
 321                                         ($row['rows'] >= intval($this->configCache->get('system', 'db_loglimit_index'))));
 322                         } else {
 323                                 $log = false;
 324                         }
 325
 326                         if ((intval($this->configCache->get('system', 'db_loglimit_index_high')) > 0) && ($row['rows'] >= intval($this->configCache->get('system', 'db_loglimit_index_high')))) {
 327                                 $log = true;
 328                         }
 329
 330                         if (in_array($row['key'], $denylist) || ($row['key'] == "")) {
 331                                 $log = false;
 332                         }
 333
 334                         if ($log) {
 335                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 336                                 @file_put_contents($this->configCache->get('system', 'db_log_index'), DateTimeFormat::utcNow() . "\t" .
 337                                                                                                       $row['key'] . "\t" . $row['rows'] . "\t" . $row['Extra'] . "\t" .
 338                                                                                                       basename($backtrace[1]["file"]) . "\t" .
 339                                                                                                       $backtrace[1]["line"] . "\t" . $backtrace[2]["function"] . "\t" .
 340                                                                                                       substr($query, 0, 4000) . "\n", FILE_APPEND);
 341                         }
 342                 }
 343         }
 344
 345         /**
 346          * Removes every not allowlisted character from the identifier string
 347          *
 348          * @param string $identifier
 349          *
 350          * @return string sanitized identifier
 351          * @throws \Exception
 352          */
 353         private function sanitizeIdentifier($identifier)
 354         {
 355                 return preg_replace('/[^A-Za-z0-9_\-]+/', '', $identifier);
 356         }
 357
 358         public function escape($str)
 359         {
 360                 if ($this->connected) {
 361                         switch ($this->driver) {
 362                                 case self::PDO:
 363                                         return substr(@$this->connection->quote($str, PDO::PARAM_STR), 1, -1);
 364
 365                                 case self::MYSQLI:
 366                                         return @$this->connection->real_escape_string($str);
 367                         }
 368                 } else {
 369                         return str_replace("'", "\\'", $str);
 370                 }
 371         }
 372
 373         public function isConnected()
 374         {
 375                 return $this->connected;
 376         }
 377
 378         public function connected()
 379         {
 380                 $connected = false;
 381
 382                 if (is_null($this->connection)) {
 383                         return false;
 384                 }
 385
 386                 switch ($this->driver) {
 387                         case self::PDO:
 388                                 $r = $this->p("SELECT 1");
 389                                 $connected = $this->isResult($r);
 390 //                              if ($this->isResult($r)) {
 391 //                                      $row       = $this->toArray($r);
 392 //                                      $connected = ($row[0]['1'] == '1');
 393 //                              }
 394                                 break;
 395                         case self::MYSQLI:
 396                                 $connected = $this->connection->ping();
 397                                 break;
 398                 }
 399
 400                 return $connected;
 401         }
 402
 403         /**
 404          * Replaces ANY_VALUE() function by MIN() function,
 405          * if the database server does not support ANY_VALUE().
 406          *
 407          * Considerations for Standard SQL, or MySQL with ONLY_FULL_GROUP_BY (default since 5.7.5).
 408          * ANY_VALUE() is available from MySQL 5.7.5 https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html
 409          * A standard fall-back is to use MIN().
 410          *
 411          * @param string $sql An SQL string without the values
 412          *
 413          * @return string The input SQL string modified if necessary.
 414          */
 415         public function anyValueFallback($sql)
 416         {
 417                 $server_info = $this->serverInfo();
 418                 if (version_compare($server_info, '5.7.5', '<') ||
 419                     (stripos($server_info, 'MariaDB') !== false)) {
 420                         $sql = str_ireplace('ANY_VALUE(', 'MIN(', $sql);
 421                 }
 422                 return $sql;
 423         }
 424
 425         /**
 426          * Replaces the ? placeholders with the parameters in the $args array
 427          *
 428          * @param string $sql  SQL query
 429          * @param array  $args The parameters that are to replace the ? placeholders
 430          *
 431          * @return string The replaced SQL query
 432          */
 433         private function replaceParameters($sql, $args)
 434         {
 435                 $offset = 0;
 436                 foreach ($args AS $param => $value) {
 437                         if (is_int($args[$param]) || is_float($args[$param]) || is_bool($args[$param])) {
 438                                 $replace = intval($args[$param]);
 439                         } elseif (is_null($args[$param])) {
 440                                 $replace = 'NULL';
 441                         } else {
 442                                 $replace = "'" . $this->escape($args[$param]) . "'";
 443                         }
 444
 445                         $pos = strpos($sql, '?', $offset);
 446                         if ($pos !== false) {
 447                                 $sql = substr_replace($sql, $replace, $pos, 1);
 448                         }
 449                         $offset = $pos + strlen($replace);
 450                 }
 451                 return $sql;
 452         }
 453
 454         /**
 455          * Executes a prepared statement that returns data
 456          *
 457          * @usage Example: $r = p("SELECT * FROM `item` WHERE `guid` = ?", $guid);
 458          *
 459          * Please only use it with complicated queries.
 460          * For all regular queries please use DBA::select or DBA::exists
 461          *
 462          * @param string $sql SQL statement
 463          *
 464          * @return bool|object statement object or result object
 465          * @throws \Exception
 466          */
 467         public function p($sql)
 468         {
 469
 470                 $stamp1 = microtime(true);
 471
 472                 $params = DBA::getParam(func_get_args());
 473
 474                 // Renumber the array keys to be sure that they fit
 475                 $i    = 0;
 476                 $args = [];
 477                 foreach ($params AS $param) {
 478                         // Avoid problems with some MySQL servers and boolean values. See issue #3645
 479                         if (is_bool($param)) {
 480                                 $param = (int)$param;
 481                         }
 482                         $args[++$i] = $param;
 483                 }
 484
 485                 if (!$this->connected) {
 486                         return false;
 487                 }
 488
 489                 if ((substr_count($sql, '?') != count($args)) && (count($args) > 0)) {
 490                         // Question: Should we continue or stop the query here?
 491                         $this->logger->warning('Query parameters mismatch.', ['query' => $sql, 'args' => $args, 'callstack' => System::callstack()]);
 492                 }
 493
 494                 $sql = DBA::cleanQuery($sql);
 495                 $sql = $this->anyValueFallback($sql);
 496
 497                 $orig_sql = $sql;
 498
 499                 if ($this->configCache->get('system', 'db_callstack') !== null) {
 500                         $sql = "/*" . System::callstack() . " */ " . $sql;
 501                 }
 502
 503                 $is_error            = false;
 504                 $this->error         = '';
 505                 $this->errorno       = 0;
 506                 $this->affected_rows = 0;
 507
 508                 // We have to make some things different if this function is called from "e"
 509                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
 510
 511                 if (isset($trace[1])) {
 512                         $called_from = $trace[1];
 513                 } else {
 514                         // We use just something that is defined to avoid warnings
 515                         $called_from = $trace[0];
 516                 }
 517                 // We are having an own error logging in the function "e"
 518                 $called_from_e = ($called_from['function'] == 'e');
 519
 520                 if (!isset($this->connection)) {
 521                         throw new InternalServerErrorException('The Connection is empty, although connected is set true.');
 522                 }
 523
 524                 switch ($this->driver) {
 525                         case self::PDO:
 526                                 // If there are no arguments we use "query"
 527                                 if ($this->emulate_prepares || count($args) == 0) {
 528                                         if (!$retval = $this->connection->query($this->replaceParameters($sql, $args))) {
 529                                                 $errorInfo     = $this->connection->errorInfo();
 530                                                 $this->error   = $errorInfo[2];
 531                                                 $this->errorno = $errorInfo[1];
 532                                                 $retval        = false;
 533                                                 $is_error      = true;
 534                                                 break;
 535                                         }
 536                                         $this->affected_rows = $retval->rowCount();
 537                                         break;
 538                                 }
 539
 540                                 /** @var $stmt mysqli_stmt|PDOStatement */
 541                                 if (!$stmt = $this->connection->prepare($sql)) {
 542                                         $errorInfo     = $this->connection->errorInfo();
 543                                         $this->error   = $errorInfo[2];
 544                                         $this->errorno = $errorInfo[1];
 545                                         $retval        = false;
 546                                         $is_error      = true;
 547                                         break;
 548                                 }
 549
 550                                 foreach ($args AS $param => $value) {
 551                                         if (is_int($args[$param])) {
 552                                                 $data_type = PDO::PARAM_INT;
 553                                         } else {
 554                                                 $data_type = PDO::PARAM_STR;
 555                                         }
 556                                         $stmt->bindParam($param, $args[$param], $data_type);
 557                                 }
 558
 559                                 if (!$stmt->execute()) {
 560                                         $errorInfo     = $stmt->errorInfo();
 561                                         $this->error   = $errorInfo[2];
 562                                         $this->errorno = $errorInfo[1];
 563                                         $retval        = false;
 564                                         $is_error      = true;
 565                                 } else {
 566                                         $retval              = $stmt;
 567                                         $this->affected_rows = $retval->rowCount();
 568                                 }
 569                                 break;
 570                         case self::MYSQLI:
 571                                 // There are SQL statements that cannot be executed with a prepared statement
 572                                 $parts           = explode(' ', $orig_sql);
 573                                 $command         = strtolower($parts[0]);
 574                                 $can_be_prepared = in_array($command, ['select', 'update', 'insert', 'delete']);
 575
 576                                 // The fallback routine is called as well when there are no arguments
 577                                 if ($this->emulate_prepares || !$can_be_prepared || (count($args) == 0)) {
 578                                         $retval = $this->connection->query($this->replaceParameters($sql, $args));
 579                                         if ($this->connection->errno) {
 580                                                 $this->error   = $this->connection->error;
 581                                                 $this->errorno = $this->connection->errno;
 582                                                 $retval        = false;
 583                                                 $is_error      = true;
 584                                         } else {
 585                                                 if (isset($retval->num_rows)) {
 586                                                         $this->affected_rows = $retval->num_rows;
 587                                                 } else {
 588                                                         $this->affected_rows = $this->connection->affected_rows;
 589                                                 }
 590                                         }
 591                                         break;
 592                                 }
 593
 594                                 $stmt = $this->connection->stmt_init();
 595
 596                                 if (!$stmt->prepare($sql)) {
 597                                         $this->error   = $stmt->error;
 598                                         $this->errorno = $stmt->errno;
 599                                         $retval        = false;
 600                                         $is_error      = true;
 601                                         break;
 602                                 }
 603
 604                                 $param_types = '';
 605                                 $values      = [];
 606                                 foreach ($args AS $param => $value) {
 607                                         if (is_int($args[$param])) {
 608                                                 $param_types .= 'i';
 609                                         } elseif (is_float($args[$param])) {
 610                                                 $param_types .= 'd';
 611                                         } elseif (is_string($args[$param])) {
 612                                                 $param_types .= 's';
 613                                         } else {
 614                                                 $param_types .= 'b';
 615                                         }
 616                                         $values[] = &$args[$param];
 617                                 }
 618
 619                                 if (count($values) > 0) {
 620                                         array_unshift($values, $param_types);
 621                                         call_user_func_array([$stmt, 'bind_param'], $values);
 622                                 }
 623
 624                                 if (!$stmt->execute()) {
 625                                         $this->error   = $this->connection->error;
 626                                         $this->errorno = $this->connection->errno;
 627                                         $retval        = false;
 628                                         $is_error      = true;
 629                                 } else {
 630                                         $stmt->store_result();
 631                                         $retval              = $stmt;
 632                                         $this->affected_rows = $retval->affected_rows;
 633                                 }
 634                                 break;
 635                 }
 636
 637                 // See issue https://github.com/friendica/friendica/issues/8572
 638                 // Ensure that we always get an error message on an error.
 639                 if ($is_error && empty($this->errorno)) {
 640                         $this->errorno = -1;
 641                 }
 642
 643                 if ($is_error && empty($this->error)) {
 644                         $this->error = 'Unknown database error';
 645                 }
 646
 647                 // We are having an own error logging in the function "e"
 648                 if (($this->errorno != 0) && !$called_from_e) {
 649                         // We have to preserve the error code, somewhere in the logging it get lost
 650                         $error   = $this->error;
 651                         $errorno = $this->errorno;
 652
 653                         if ($this->testmode) {
 654                                 throw new DatabaseException($error, $errorno, $this->replaceParameters($sql, $args));
 655                         }
 656
 657                         $this->logger->error('DB Error', [
 658                                 'code'      => $errorno,
 659                                 'error'     => $error,
 660                                 'callstack' => System::callstack(8),
 661                                 'params'    => $this->replaceParameters($sql, $args),
 662                         ]);
 663
 664                         // On a lost connection we try to reconnect - but only once.
 665                         if ($errorno == 2006) {
 666                                 if ($this->in_retrial || !$this->reconnect()) {
 667                                         // It doesn't make sense to continue when the database connection was lost
 668                                         if ($this->in_retrial) {
 669                                                 $this->logger->notice('Giving up retrial because of database error', [
 670                                                         'code'  => $errorno,
 671                                                         'error' => $error,
 672                                                 ]);
 673                                         } else {
 674                                                 $this->logger->notice('Couldn\'t reconnect after database error', [
 675                                                         'code'  => $errorno,
 676                                                         'error' => $error,
 677                                                 ]);
 678                                         }
 679                                         exit(1);
 680                                 } else {
 681                                         // We try it again
 682                                         $this->logger->notice('Reconnected after database error', [
 683                                                 'code'  => $errorno,
 684                                                 'error' => $error,
 685                                         ]);
 686                                         $this->in_retrial = true;
 687                                         $ret              = $this->p($sql, $args);
 688                                         $this->in_retrial = false;
 689                                         return $ret;
 690                                 }
 691                         }
 692
 693                         $this->error   = $error;
 694                         $this->errorno = $errorno;
 695                 }
 696
 697                 $this->profiler->saveTimestamp($stamp1, 'database');
 698
 699                 if ($this->configCache->get('system', 'db_log')) {
 700                         $stamp2   = microtime(true);
 701                         $duration = (float)($stamp2 - $stamp1);
 702
 703                         if (($duration > $this->configCache->get('system', 'db_loglimit'))) {
 704                                 $duration  = round($duration, 3);
 705                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 706
 707                                 @file_put_contents($this->configCache->get('system', 'db_log'), DateTimeFormat::utcNow() . "\t" . $duration . "\t" .
 708                                                                                                 basename($backtrace[1]["file"]) . "\t" .
 709                                                                                                 $backtrace[1]["line"] . "\t" . $backtrace[2]["function"] . "\t" .
 710                                                                                                 substr($this->replaceParameters($sql, $args), 0, 4000) . "\n", FILE_APPEND);
 711                         }
 712                 }
 713                 return $retval;
 714         }
 715
 716         /**
 717          * Executes a prepared statement like UPDATE or INSERT that doesn't return data
 718          *
 719          * Please use DBA::delete, DBA::insert, DBA::update, ... instead
 720          *
 721          * @param string $sql SQL statement
 722          *
 723          * @return boolean Was the query successfull? False is returned only if an error occurred
 724          * @throws \Exception
 725          */
 726         public function e($sql)
 727         {
 728
 729                 $stamp = microtime(true);
 730
 731                 $params = DBA::getParam(func_get_args());
 732
 733                 // In a case of a deadlock we are repeating the query 20 times
 734                 $timeout = 20;
 735
 736                 do {
 737                         $stmt = $this->p($sql, $params);
 738
 739                         if (is_bool($stmt)) {
 740                                 $retval = $stmt;
 741                         } elseif (is_object($stmt)) {
 742                                 $retval = true;
 743                         } else {
 744                                 $retval = false;
 745                         }
 746
 747                         $this->close($stmt);
 748
 749                 } while (($this->errorno == 1213) && (--$timeout > 0));
 750
 751                 if ($this->errorno != 0) {
 752                         // We have to preserve the error code, somewhere in the logging it get lost
 753                         $error   = $this->error;
 754                         $errorno = $this->errorno;
 755
 756                         if ($this->testmode) {
 757                                 throw new DatabaseException($error, $errorno, $this->replaceParameters($sql, $params));
 758                         }
 759
 760                         $this->logger->error('DB Error', [
 761                                 'code'      => $errorno,
 762                                 'error'     => $error,
 763                                 'callstack' => System::callstack(8),
 764                                 'params'    => $this->replaceParameters($sql, $params),
 765                         ]);
 766
 767                         // On a lost connection we simply quit.
 768                         // A reconnect like in $this->p could be dangerous with modifications
 769                         if ($errorno == 2006) {
 770                                 $this->logger->notice('Giving up because of database error', [
 771                                         'code'  => $errorno,
 772                                         'error' => $error,
 773                                 ]);
 774                                 exit(1);
 775                         }
 776
 777                         $this->error   = $error;
 778                         $this->errorno = $errorno;
 779                 }
 780
 781                 $this->profiler->saveTimestamp($stamp, "database_write");
 782
 783                 return $retval;
 784         }
 785
 786         /**
 787          * Check if data exists
 788          *
 789          * @param string|array $table     Table name or array [schema => table]
 790          * @param array        $condition array of fields for condition
 791          *
 792          * @return boolean Are there rows for that condition?
 793          * @throws \Exception
 794          */
 795         public function exists($table, $condition)
 796         {
 797                 if (empty($table)) {
 798                         return false;
 799                 }
 800
 801                 $fields = [];
 802
 803                 if (empty($condition)) {
 804                         return DBStructure::existsTable($table);
 805                 }
 806
 807                 reset($condition);
 808                 $first_key = key($condition);
 809                 if (!is_int($first_key)) {
 810                         $fields = [$first_key];
 811                 }
 812
 813                 $stmt = $this->select($table, $fields, $condition, ['limit' => 1]);
 814
 815                 if (is_bool($stmt)) {
 816                         $retval = $stmt;
 817                 } else {
 818                         $retval = ($this->numRows($stmt) > 0);
 819                 }
 820
 821                 $this->close($stmt);
 822
 823                 return $retval;
 824         }
 825
 826         /**
 827          * Fetches the first row
 828          *
 829          * Please use DBA::selectFirst or DBA::exists whenever this is possible.
 830          *
 831          * Fetches the first row
 832          *
 833          * @param string $sql SQL statement
 834          *
 835          * @return array first row of query
 836          * @throws \Exception
 837          */
 838         public function fetchFirst($sql)
 839         {
 840                 $params = DBA::getParam(func_get_args());
 841
 842                 $stmt = $this->p($sql, $params);
 843
 844                 if (is_bool($stmt)) {
 845                         $retval = $stmt;
 846                 } else {
 847                         $retval = $this->fetch($stmt);
 848                 }
 849
 850                 $this->close($stmt);
 851
 852                 return $retval;
 853         }
 854
 855         /**
 856          * Returns the number of affected rows of the last statement
 857          *
 858          * @return int Number of rows
 859          */
 860         public function affectedRows()
 861         {
 862                 return $this->affected_rows;
 863         }
 864
 865         /**
 866          * Returns the number of columns of a statement
 867          *
 868          * @param object Statement object
 869          *
 870          * @return int Number of columns
 871          */
 872         public function columnCount($stmt)
 873         {
 874                 if (!is_object($stmt)) {
 875                         return 0;
 876                 }
 877                 switch ($this->driver) {
 878                         case self::PDO:
 879                                 return $stmt->columnCount();
 880                         case self::MYSQLI:
 881                                 return $stmt->field_count;
 882                 }
 883                 return 0;
 884         }
 885
 886         /**
 887          * Returns the number of rows of a statement
 888          *
 889          * @param PDOStatement|mysqli_result|mysqli_stmt Statement object
 890          *
 891          * @return int Number of rows
 892          */
 893         public function numRows($stmt)
 894         {
 895                 if (!is_object($stmt)) {
 896                         return 0;
 897                 }
 898                 switch ($this->driver) {
 899                         case self::PDO:
 900                                 return $stmt->rowCount();
 901                         case self::MYSQLI:
 902                                 return $stmt->num_rows;
 903                 }
 904                 return 0;
 905         }
 906
 907         /**
 908          * Fetch a single row
 909          *
 910          * @param mixed $stmt statement object
 911          *
 912          * @return array current row
 913          */
 914         public function fetch($stmt)
 915         {
 916
 917                 $stamp1 = microtime(true);
 918
 919                 $columns = [];
 920
 921                 if (!is_object($stmt)) {
 922                         return false;
 923                 }
 924
 925                 switch ($this->driver) {
 926                         case self::PDO:
 927                                 $columns = $stmt->fetch(PDO::FETCH_ASSOC);
 928                                 break;
 929                         case self::MYSQLI:
 930                                 if (get_class($stmt) == 'mysqli_result') {
 931                                         $columns = $stmt->fetch_assoc();
 932                                         break;
 933                                 }
 934
 935                                 // This code works, but is slow
 936
 937                                 // Bind the result to a result array
 938                                 $cols = [];
 939
 940                                 $cols_num = [];
 941                                 for ($x = 0; $x < $stmt->field_count; $x++) {
 942                                         $cols[] = &$cols_num[$x];
 943                                 }
 944
 945                                 call_user_func_array([$stmt, 'bind_result'], $cols);
 946
 947                                 if (!$stmt->fetch()) {
 948                                         return false;
 949                                 }
 950
 951                                 // The slow part:
 952                                 // We need to get the field names for the array keys
 953                                 // It seems that there is no better way to do this.
 954                                 $result = $stmt->result_metadata();
 955                                 $fields = $result->fetch_fields();
 956
 957                                 foreach ($cols_num AS $param => $col) {
 958                                         $columns[$fields[$param]->name] = $col;
 959                                 }
 960                 }
 961
 962                 $this->profiler->saveTimestamp($stamp1, 'database');
 963
 964                 return $columns;
 965         }
 966
 967         /**
 968          * Insert a row into a table
 969          *
 970          * @param string|array $table               Table name or array [schema => table]
 971          * @param array        $param               parameter array
 972          * @param bool         $on_duplicate_update Do an update on a duplicate entry
 973          *
 974          * @return boolean was the insert successful?
 975          * @throws \Exception
 976          */
 977         public function insert($table, array $param, bool $on_duplicate_update = false)
 978         {
 979                 if (empty($table) || empty($param)) {
 980                         $this->logger->info('Table and fields have to be set');
 981                         return false;
 982                 }
 983
 984                 $table_string = DBA::buildTableString($table);
 985
 986                 $fields_string = implode(', ', array_map([DBA::class, 'quoteIdentifier'], array_keys($param)));
 987
 988                 $values_string = substr(str_repeat("?, ", count($param)), 0, -2);
 989
 990                 $sql = "INSERT INTO " . $table_string . " (" . $fields_string . ") VALUES (" . $values_string . ")";
 991
 992                 if ($on_duplicate_update) {
 993                         $fields_string = implode(' = ?, ', array_map([DBA::class, 'quoteIdentifier'], array_keys($param)));
 994
 995                         $sql .= " ON DUPLICATE KEY UPDATE " . $fields_string . " = ?";
 996
 997                         $values = array_values($param);
 998                         $param  = array_merge_recursive($values, $values);
 999                 }
1000
1001                 return $this->e($sql, $param);
1002         }
1003
1004         /**
1005          * Inserts a row with the provided data in the provided table.
1006          * If the data corresponds to an existing row through a UNIQUE or PRIMARY index constraints, it updates the row instead.
1007          *
1008          * @param string|array $table Table name or array [schema => table]
1009          * @param array        $param parameter array
1010          *
1011          * @return boolean was the insert successful?
1012          * @throws \Exception
1013          */
1014         public function replace($table, array $param)
1015         {
1016                 if (empty($table) || empty($param)) {
1017                         $this->logger->info('Table and fields have to be set');
1018                         return false;
1019                 }
1020
1021                 $table_string = DBA::buildTableString($table);
1022
1023                 $fields_string = implode(', ', array_map([DBA::class, 'quoteIdentifier'], array_keys($param)));
1024
1025                 $values_string = substr(str_repeat("?, ", count($param)), 0, -2);
1026
1027                 $sql = "REPLACE " . $table_string . " (" . $fields_string . ") VALUES (" . $values_string . ")";
1028
1029                 return $this->e($sql, $param);
1030         }
1031
1032         /**
1033          * Fetch the id of the last insert command
1034          *
1035          * @return integer Last inserted id
1036          */
1037         public function lastInsertId()
1038         {
1039                 switch ($this->driver) {
1040                         case self::PDO:
1041                                 $id = $this->connection->lastInsertId();
1042                                 break;
1043                         case self::MYSQLI:
1044                                 $id = $this->connection->insert_id;
1045                                 break;
1046                 }
1047                 return (int)$id;
1048         }
1049
1050         /**
1051          * Locks a table for exclusive write access
1052          *
1053          * This function can be extended in the future to accept a table array as well.
1054          *
1055          * @param string|array $table Table name or array [schema => table]
1056          *
1057          * @return boolean was the lock successful?
1058          * @throws \Exception
1059          */
1060         public function lock($table)
1061         {
1062                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
1063                 if ($this->driver == self::PDO) {
1064                         $this->e("SET autocommit=0");
1065                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
1066                 } else {
1067                         $this->connection->autocommit(false);
1068                 }
1069
1070                 $success = $this->e("LOCK TABLES " . DBA::buildTableString($table) . " WRITE");
1071
1072                 if ($this->driver == self::PDO) {
1073                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->pdo_emulate_prepares);
1074                 }
1075
1076                 if (!$success) {
1077                         if ($this->driver == self::PDO) {
1078                                 $this->e("SET autocommit=1");
1079                         } else {
1080                                 $this->connection->autocommit(true);
1081                         }
1082                 } else {
1083                         $this->in_transaction = true;
1084                 }
1085                 return $success;
1086         }
1087
1088         /**
1089          * Unlocks all locked tables
1090          *
1091          * @return boolean was the unlock successful?
1092          * @throws \Exception
1093          */
1094         public function unlock()
1095         {
1096                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
1097                 $this->performCommit();
1098
1099                 if ($this->driver == self::PDO) {
1100                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
1101                 }
1102
1103                 $success = $this->e("UNLOCK TABLES");
1104
1105                 if ($this->driver == self::PDO) {
1106                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->pdo_emulate_prepares);
1107                         $this->e("SET autocommit=1");
1108                 } else {
1109                         $this->connection->autocommit(true);
1110                 }
1111
1112                 $this->in_transaction = false;
1113                 return $success;
1114         }
1115
1116         /**
1117          * Starts a transaction
1118          *
1119          * @return boolean Was the command executed successfully?
1120          */
1121         public function transaction()
1122         {
1123                 if (!$this->performCommit()) {
1124                         return false;
1125                 }
1126
1127                 switch ($this->driver) {
1128                         case self::PDO:
1129                                 if (!$this->connection->inTransaction() && !$this->connection->beginTransaction()) {
1130                                         return false;
1131                                 }
1132                                 break;
1133
1134                         case self::MYSQLI:
1135                                 if (!$this->connection->begin_transaction()) {
1136                                         return false;
1137                                 }
1138                                 break;
1139                 }
1140
1141                 $this->in_transaction = true;
1142                 return true;
1143         }
1144
1145         protected function performCommit()
1146         {
1147                 switch ($this->driver) {
1148                         case self::PDO:
1149                                 if (!$this->connection->inTransaction()) {
1150                                         return true;
1151                                 }
1152
1153                                 return $this->connection->commit();
1154
1155                         case self::MYSQLI:
1156                                 return $this->connection->commit();
1157                 }
1158
1159                 return true;
1160         }
1161
1162         /**
1163          * Does a commit
1164          *
1165          * @return boolean Was the command executed successfully?
1166          */
1167         public function commit()
1168         {
1169                 if (!$this->performCommit()) {
1170                         return false;
1171                 }
1172                 $this->in_transaction = false;
1173                 return true;
1174         }
1175
1176         /**
1177          * Does a rollback
1178          *
1179          * @return boolean Was the command executed successfully?
1180          */
1181         public function rollback()
1182         {
1183                 $ret = false;
1184
1185                 switch ($this->driver) {
1186                         case self::PDO:
1187                                 if (!$this->connection->inTransaction()) {
1188                                         $ret = true;
1189                                         break;
1190                                 }
1191                                 $ret = $this->connection->rollBack();
1192                                 break;
1193
1194                         case self::MYSQLI:
1195                                 $ret = $this->connection->rollback();
1196                                 break;
1197                 }
1198                 $this->in_transaction = false;
1199                 return $ret;
1200         }
1201
1202         /**
1203          * Build the array with the table relations
1204          *
1205          * The array is build from the database definitions in DBStructure.php
1206          *
1207          * This process must only be started once, since the value is cached.
1208          */
1209         private function buildRelationData()
1210         {
1211                 $definition = DBStructure::definition($this->configCache->get('system', 'basepath'));
1212
1213                 foreach ($definition AS $table => $structure) {
1214                         foreach ($structure['fields'] AS $field => $field_struct) {
1215                                 if (isset($field_struct['relation'])) {
1216                                         foreach ($field_struct['relation'] AS $rel_table => $rel_field) {
1217                                                 $this->relation[$rel_table][$rel_field][$table][] = $field;
1218                                         }
1219                                 }
1220                         }
1221                 }
1222         }
1223
1224         /**
1225          * Delete a row from a table
1226          *
1227          * Note: this methods does NOT accept schema => table arrays because of the complex relation stuff.
1228          *
1229          * @param string $table      Table name
1230          * @param array  $conditions Field condition(s)
1231          * @param array  $options
1232          *                           - cascade: If true we delete records in other tables that depend on the one we're deleting through
1233          *                           relations (default: true)
1234          * @param array  $callstack  Internal use: prevent endless loops
1235          *
1236          * @return boolean was the delete successful?
1237          * @throws \Exception
1238          */
1239         public function delete($table, array $conditions, array $options = [], array &$callstack = [])
1240         {
1241                 if (empty($table) || empty($conditions)) {
1242                         $this->logger->info('Table and conditions have to be set');
1243                         return false;
1244                 }
1245
1246                 $commands = [];
1247
1248                 // Create a key for the loop prevention
1249                 $key = $table . ':' . json_encode($conditions);
1250
1251                 // We quit when this key already exists in the callstack.
1252                 if (isset($callstack[$key])) {
1253                         return true;
1254                 }
1255
1256                 $callstack[$key] = true;
1257
1258                 $commands[$key] = ['table' => $table, 'conditions' => $conditions];
1259
1260                 // Don't use "defaults" here, since it would set "false" to "true"
1261                 if (isset($options['cascade'])) {
1262                         $cascade = $options['cascade'];
1263                 } else {
1264                         $cascade = true;
1265                 }
1266
1267                 // To speed up the whole process we cache the table relations
1268                 if ($cascade && count($this->relation) == 0) {
1269                         $this->buildRelationData();
1270                 }
1271
1272                 // Is there a relation entry for the table?
1273                 if ($cascade && isset($this->relation[$table])) {
1274                         // We only allow a simple "one field" relation.
1275                         $field   = array_keys($this->relation[$table])[0];
1276                         $rel_def = array_values($this->relation[$table])[0];
1277
1278                         // Create a key for preventing double queries
1279                         $qkey = $field . '-' . $table . ':' . json_encode($conditions);
1280
1281                         // When the search field is the relation field, we don't need to fetch the rows
1282                         // This is useful when the leading record is already deleted in the frontend but the rest is done in the backend
1283                         if ((count($conditions) == 1) && ($field == array_keys($conditions)[0])) {
1284                                 foreach ($rel_def AS $rel_table => $rel_fields) {
1285                                         foreach ($rel_fields AS $rel_field) {
1286                                                 $this->delete($rel_table, [$rel_field => array_values($conditions)[0]], $options, $callstack);
1287                                         }
1288                                 }
1289                                 // We quit when this key already exists in the callstack.
1290                         } elseif (!isset($callstack[$qkey])) {
1291                                 $callstack[$qkey] = true;
1292
1293                                 // Fetch all rows that are to be deleted
1294                                 $data = $this->select($table, [$field], $conditions);
1295
1296                                 while ($row = $this->fetch($data)) {
1297                                         $this->delete($table, [$field => $row[$field]], $options, $callstack);
1298                                 }
1299
1300                                 $this->close($data);
1301
1302                                 // Since we had split the delete command we don't need the original command anymore
1303                                 unset($commands[$key]);
1304                         }
1305                 }
1306
1307                 // Now we finalize the process
1308                 $do_transaction = !$this->in_transaction;
1309
1310                 if ($do_transaction) {
1311                         $this->transaction();
1312                 }
1313
1314                 $compacted = [];
1315                 $counter   = [];
1316
1317                 foreach ($commands AS $command) {
1318                         $conditions = $command['conditions'];
1319                         reset($conditions);
1320                         $first_key = key($conditions);
1321
1322                         $condition_string = DBA::buildCondition($conditions);
1323
1324                         if ((count($command['conditions']) > 1) || is_int($first_key)) {
1325                                 $sql = "DELETE FROM " . DBA::quoteIdentifier($command['table']) . " " . $condition_string;
1326                                 $this->logger->info($this->replaceParameters($sql, $conditions), ['callstack' => System::callstack(6), 'internal_callstack' => $callstack]);
1327
1328                                 if (!$this->e($sql, $conditions)) {
1329                                         if ($do_transaction) {
1330                                                 $this->rollback();
1331                                         }
1332                                         return false;
1333                                 }
1334                         } else {
1335                                 $key_table     = $command['table'];
1336                                 $key_condition = array_keys($command['conditions'])[0];
1337                                 $value         = array_values($command['conditions'])[0];
1338
1339                                 // Split the SQL queries in chunks of 100 values
1340                                 // We do the $i stuff here to make the code better readable
1341                                 $i = isset($counter[$key_table][$key_condition]) ? $counter[$key_table][$key_condition] : 0;
1342                                 if (isset($compacted[$key_table][$key_condition][$i]) && count($compacted[$key_table][$key_condition][$i]) > 100) {
1343                                         ++$i;
1344                                 }
1345
1346                                 $compacted[$key_table][$key_condition][$i][$value] = $value;
1347                                 $counter[$key_table][$key_condition]               = $i;
1348                         }
1349                 }
1350                 foreach ($compacted AS $table => $values) {
1351                         foreach ($values AS $field => $field_value_list) {
1352                                 foreach ($field_value_list AS $field_values) {
1353                                         $sql = "DELETE FROM " . DBA::quoteIdentifier($table) . " WHERE " . DBA::quoteIdentifier($field) . " IN (" .
1354                                                substr(str_repeat("?, ", count($field_values)), 0, -2) . ");";
1355
1356                                         $this->logger->info($this->replaceParameters($sql, $field_values), ['callstack' => System::callstack(6), 'internal_callstack' => $callstack]);
1357
1358                                         if (!$this->e($sql, $field_values)) {
1359                                                 if ($do_transaction) {
1360                                                         $this->rollback();
1361                                                 }
1362                                                 return false;
1363                                         }
1364                                 }
1365                         }
1366                 }
1367                 if ($do_transaction) {
1368                         $this->commit();
1369                 }
1370                 return true;
1371         }
1372
1373         /**
1374          * Updates rows
1375          *
1376          * Updates rows in the database. When $old_fields is set to an array,
1377          * the system will only do an update if the fields in that array changed.
1378          *
1379          * Attention:
1380          * Only the values in $old_fields are compared.
1381          * This is an intentional behaviour.
1382          *
1383          * Example:
1384          * We include the timestamp field in $fields but not in $old_fields.
1385          * Then the row will only get the new timestamp when the other fields had changed.
1386          *
1387          * When $old_fields is set to a boolean value the system will do this compare itself.
1388          * When $old_fields is set to "true" the system will do an insert if the row doesn't exists.
1389          *
1390          * Attention:
1391          * Only set $old_fields to a boolean value when you are sure that you will update a single row.
1392          * When you set $old_fields to "true" then $fields must contain all relevant fields!
1393          *
1394          * @param string|array  $table      Table name or array [schema => table]
1395          * @param array         $fields     contains the fields that are updated
1396          * @param array         $condition  condition array with the key values
1397          * @param array|boolean $old_fields array with the old field values that are about to be replaced (true = update on duplicate)
1398          *
1399          * @return boolean was the update successfull?
1400          * @throws \Exception
1401          */
1402         public function update($table, $fields, $condition, $old_fields = [])
1403         {
1404                 if (empty($table) || empty($fields) || empty($condition)) {
1405                         $this->logger->info('Table, fields and condition have to be set');
1406                         return false;
1407                 }
1408
1409                 if (is_bool($old_fields)) {
1410                         $do_insert = $old_fields;
1411
1412                         $old_fields = $this->selectFirst($table, [], $condition);
1413
1414                         if (is_bool($old_fields)) {
1415                                 if ($do_insert) {
1416                                         $values = array_merge($condition, $fields);
1417                                         return $this->replace($table, $values);
1418                                 }
1419                                 $old_fields = [];
1420                         }
1421                 }
1422
1423                 foreach ($old_fields AS $fieldname => $content) {
1424                         if (isset($fields[$fieldname]) && !is_null($content) && ($fields[$fieldname] == $content)) {
1425                                 unset($fields[$fieldname]);
1426                         }
1427                 }
1428
1429                 if (count($fields) == 0) {
1430                         return true;
1431                 }
1432
1433                 $table_string = DBA::buildTableString($table);
1434
1435                 $condition_string = DBA::buildCondition($condition);
1436
1437                 $sql = "UPDATE " . $table_string . " SET "
1438                         . implode(" = ?, ", array_map([DBA::class, 'quoteIdentifier'], array_keys($fields))) . " = ?"
1439                         . $condition_string;
1440
1441                 // Combines the updated fields parameter values with the condition parameter values
1442                 $params  = array_merge(array_values($fields), $condition);
1443
1444                 return $this->e($sql, $params);
1445         }
1446
1447         /**
1448          * Retrieve a single record from a table and returns it in an associative array
1449          *
1450          * @param string|array $table
1451          * @param array        $fields
1452          * @param array        $condition
1453          * @param array        $params
1454          *
1455          * @return bool|array
1456          * @throws \Exception
1457          * @see   $this->select
1458          */
1459         public function selectFirst($table, array $fields = [], array $condition = [], $params = [])
1460         {
1461                 $params['limit'] = 1;
1462                 $result          = $this->select($table, $fields, $condition, $params);
1463
1464                 if (is_bool($result)) {
1465                         return $result;
1466                 } else {
1467                         $row = $this->fetch($result);
1468                         $this->close($result);
1469                         return $row;
1470                 }
1471         }
1472
1473         /**
1474          * Select rows from a table and fills an array with the data
1475          *
1476          * @param string|array $table     Table name or array [schema => table]
1477          * @param array        $fields    Array of selected fields, empty for all
1478          * @param array        $condition Array of fields for condition
1479          * @param array        $params    Array of several parameters
1480          *
1481          * @return array Data array
1482          * @throws \Exception
1483          * @see   self::select
1484          */
1485         public function selectToArray($table, array $fields = [], array $condition = [], array $params = [])
1486         {
1487                 return $this->toArray($this->select($table, $fields, $condition, $params));
1488         }
1489
1490         /**
1491          * Select rows from a table
1492          *
1493          *
1494          * Example:
1495          * $table = 'item';
1496          * or:
1497          * $table = ['schema' => 'table'];
1498          * @see DBA::buildTableString()
1499          *
1500          * $fields = ['id', 'uri', 'uid', 'network'];
1501          *
1502          * $condition = ['uid' => 1, 'network' => 'dspr', 'blocked' => true];
1503          * or:
1504          * $condition = ['`uid` = ? AND `network` IN (?, ?)', 1, 'dfrn', 'dspr'];
1505          * @see DBA::buildCondition()
1506          *
1507          * $params = ['order' => ['id', 'received' => true, 'created' => 'ASC'), 'limit' => 10];
1508          * @see DBA::buildParameter()
1509          *
1510          * $data = DBA::select($table, $fields, $condition, $params);
1511          *
1512          * @param string|array $table     Table name or array [schema => table]
1513          * @param array        $fields    Array of selected fields, empty for all
1514          * @param array        $condition Array of fields for condition
1515          * @param array        $params    Array of several parameters
1516          * @return boolean|object
1517          * @throws \Exception
1518          */
1519         public function select($table, array $fields = [], array $condition = [], array $params = [])
1520         {
1521                 if (empty($table)) {
1522                         return false;
1523                 }
1524
1525                 if (count($fields) > 0) {
1526                         $select_string = implode(', ', array_map([DBA::class, 'quoteIdentifier'], $fields));
1527                 } else {
1528                         $select_string = '*';
1529                 }
1530
1531                 $table_string = DBA::buildTableString($table);
1532
1533                 $condition_string = DBA::buildCondition($condition);
1534
1535                 $param_string = DBA::buildParameter($params);
1536
1537                 $sql = "SELECT " . $select_string . " FROM " . $table_string . $condition_string . $param_string;
1538
1539                 $result = $this->p($sql, $condition);
1540
1541                 return $result;
1542         }
1543
1544         /**
1545          * Counts the rows from a table satisfying the provided condition
1546          *
1547          * @param string|array $table     Table name or array [schema => table]
1548          * @param array        $condition Array of fields for condition
1549          * @param array        $params    Array of several parameters
1550          *
1551          * @return int
1552          *
1553          * Example:
1554          * $table = "item";
1555          *
1556          * $condition = ["uid" => 1, "network" => 'dspr'];
1557          * or:
1558          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1559          *
1560          * $count = DBA::count($table, $condition);
1561          * @throws \Exception
1562          */
1563         public function count($table, array $condition = [], array $params = [])
1564         {
1565                 if (empty($table)) {
1566                         return false;
1567                 }
1568
1569                 $table_string = DBA::buildTableString($table);
1570
1571                 $condition_string = DBA::buildCondition($condition);
1572
1573                 if (empty($params['expression'])) {
1574                         $expression = '*';
1575                 } elseif (!empty($params['distinct'])) {
1576                         $expression = "DISTINCT " . DBA::quoteIdentifier($params['expression']);
1577                 } else {
1578                         $expression = DBA::quoteIdentifier($params['expression']);
1579                 }
1580
1581                 $sql = "SELECT COUNT(" . $expression . ") AS `count` FROM " . $table_string . $condition_string;
1582
1583                 $row = $this->fetchFirst($sql, $condition);
1584
1585                 return $row['count'];
1586         }
1587
1588         /**
1589          * Fills an array with data from a query
1590          *
1591          * @param object $stmt statement object
1592          * @param bool   $do_close
1593          *
1594          * @return array Data array
1595          */
1596         public function toArray($stmt, $do_close = true)
1597         {
1598                 if (is_bool($stmt)) {
1599                         return [];
1600                 }
1601
1602                 $data = [];
1603                 while ($row = $this->fetch($stmt)) {
1604                         $data[] = $row;
1605                 }
1606
1607                 if ($do_close) {
1608                         $this->close($stmt);
1609                 }
1610
1611                 return $data;
1612         }
1613
1614         /**
1615          * Returns the error number of the last query
1616          *
1617          * @return string Error number (0 if no error)
1618          */
1619         public function errorNo()
1620         {
1621                 return $this->errorno;
1622         }
1623
1624         /**
1625          * Returns the error message of the last query
1626          *
1627          * @return string Error message ('' if no error)
1628          */
1629         public function errorMessage()
1630         {
1631                 return $this->error;
1632         }
1633
1634         /**
1635          * Closes the current statement
1636          *
1637          * @param object $stmt statement object
1638          *
1639          * @return boolean was the close successful?
1640          */
1641         public function close($stmt)
1642         {
1643
1644                 $stamp1 = microtime(true);
1645
1646                 if (!is_object($stmt)) {
1647                         return false;
1648                 }
1649
1650                 switch ($this->driver) {
1651                         case self::PDO:
1652                                 $ret = $stmt->closeCursor();
1653                                 break;
1654                         case self::MYSQLI:
1655                                 // MySQLi offers both a mysqli_stmt and a mysqli_result class.
1656                                 // We should be careful not to assume the object type of $stmt
1657                                 // because DBA::p() has been able to return both types.
1658                                 if ($stmt instanceof mysqli_stmt) {
1659                                         $stmt->free_result();
1660                                         $ret = $stmt->close();
1661                                 } elseif ($stmt instanceof mysqli_result) {
1662                                         $stmt->free();
1663                                         $ret = true;
1664                                 } else {
1665                                         $ret = false;
1666                                 }
1667                                 break;
1668                 }
1669
1670                 $this->profiler->saveTimestamp($stamp1, 'database');
1671
1672                 return $ret;
1673         }
1674
1675         /**
1676          * Return a list of database processes
1677          *
1678          * @return array
1679          *      'list' => List of processes, separated in their different states
1680          *      'amount' => Number of concurrent database processes
1681          * @throws \Exception
1682          */
1683         public function processlist()
1684         {
1685                 $ret  = $this->p("SHOW PROCESSLIST");
1686                 $data = $this->toArray($ret);
1687
1688                 $processes = 0;
1689                 $states    = [];
1690                 foreach ($data as $process) {
1691                         $state = trim($process["State"]);
1692
1693                         // Filter out all non blocking processes
1694                         if (!in_array($state, ["", "init", "statistics", "updating"])) {
1695                                 ++$states[$state];
1696                                 ++$processes;
1697                         }
1698                 }
1699
1700                 $statelist = "";
1701                 foreach ($states as $state => $usage) {
1702                         if ($statelist != "") {
1703                                 $statelist .= ", ";
1704                         }
1705                         $statelist .= $state . ": " . $usage;
1706                 }
1707                 return (["list" => $statelist, "amount" => $processes]);
1708         }
1709
1710         /**
1711          * Fetch a database variable
1712          *
1713          * @param string $name
1714          * @return string content
1715          */
1716         public function getVariable(string $name)
1717         {
1718                 $result = $this->fetchFirst("SHOW GLOBAL VARIABLES WHERE `Variable_name` = ?", $name);
1719                 return $result['Value'] ?? null;
1720         }
1721
1722         /**
1723          * Checks if $array is a filled array with at least one entry.
1724          *
1725          * @param mixed $array A filled array with at least one entry
1726          *
1727          * @return boolean Whether $array is a filled array or an object with rows
1728          */
1729         public function isResult($array)
1730         {
1731                 // It could be a return value from an update statement
1732                 if (is_bool($array)) {
1733                         return $array;
1734                 }
1735
1736                 if (is_object($array)) {
1737                         return $this->numRows($array) > 0;
1738                 }
1739
1740                 return (is_array($array) && (count($array) > 0));
1741         }
1742
1743         /**
1744          * Callback function for "esc_array"
1745          *
1746          * @param mixed   $value         Array value
1747          * @param string  $key           Array key
1748          * @param boolean $add_quotation add quotation marks for string values
1749          *
1750          * @return void
1751          */
1752         private function escapeArrayCallback(&$value, $key, $add_quotation)
1753         {
1754                 if (!$add_quotation) {
1755                         if (is_bool($value)) {
1756                                 $value = ($value ? '1' : '0');
1757                         } else {
1758                                 $value = $this->escape($value);
1759                         }
1760                         return;
1761                 }
1762
1763                 if (is_bool($value)) {
1764                         $value = ($value ? 'true' : 'false');
1765                 } elseif (is_float($value) || is_integer($value)) {
1766                         $value = (string)$value;
1767                 } else {
1768                         $value = "'" . $this->escape($value) . "'";
1769                 }
1770         }
1771
1772         /**
1773          * Escapes a whole array
1774          *
1775          * @param mixed   $arr           Array with values to be escaped
1776          * @param boolean $add_quotation add quotation marks for string values
1777          *
1778          * @return void
1779          */
1780         public function escapeArray(&$arr, $add_quotation = false)
1781         {
1782                 array_walk($arr, [$this, 'escapeArrayCallback'], $add_quotation);
1783         }
1784 }