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         const INSERT_DEFAULT = 0;
  46         const INSERT_UPDATE = 1;
  47         const INSERT_IGNORE = 2;
  48
  49         protected $connected = false;
  50
  51         /**
  52          * @var Cache
  53          */
  54         protected $configCache;
  55         /**
  56          * @var Profiler
  57          */
  58         protected $profiler;
  59         /**
  60          * @var LoggerInterface
  61          */
  62         protected $logger;
  63         protected $server_info    = '';
  64         /** @var PDO|mysqli */
  65         protected $connection;
  66         protected $driver;
  67         protected $pdo_emulate_prepares = false;
  68         private $error          = false;
  69         private $errorno        = 0;
  70         private $affected_rows  = 0;
  71         protected $in_transaction = false;
  72         protected $in_retrial     = false;
  73         protected $testmode       = false;
  74         private $relation       = [];
  75
  76         public function __construct(Cache $configCache, Profiler $profiler, LoggerInterface $logger)
  77         {
  78                 // We are storing these values for being able to perform a reconnect
  79                 $this->configCache   = $configCache;
  80                 $this->profiler      = $profiler;
  81                 $this->logger        = $logger;
  82
  83                 $this->connect();
  84
  85                 if ($this->isConnected()) {
  86                         // Loads DB_UPDATE_VERSION constant
  87                         DBStructure::definition($configCache->get('system', 'basepath'), false);
  88                 }
  89         }
  90
  91         public function connect()
  92         {
  93                 if (!is_null($this->connection) && $this->connected()) {
  94                         return $this->connected;
  95                 }
  96
  97                 // Reset connected state
  98                 $this->connected = false;
  99
 100                 $port       = 0;
 101                 $serveraddr = trim($this->configCache->get('database', 'hostname'));
 102                 $serverdata = explode(':', $serveraddr);
 103                 $server     = $serverdata[0];
 104                 if (count($serverdata) > 1) {
 105                         $port = trim($serverdata[1]);
 106                 }
 107
 108                 if (!empty(trim($this->configCache->get('database', 'port')))) {
 109                         $port = trim($this->configCache->get('database', 'port'));
 110                 }
 111
 112                 $server  = trim($server);
 113                 $user    = trim($this->configCache->get('database', 'username'));
 114                 $pass    = trim($this->configCache->get('database', 'password'));
 115                 $db      = trim($this->configCache->get('database', 'database'));
 116                 $charset = trim($this->configCache->get('database', 'charset'));
 117
 118                 if (!(strlen($server) && strlen($user))) {
 119                         return false;
 120                 }
 121
 122                 $persistent = (bool)$this->configCache->get('database', 'persistent');
 123
 124                 $this->pdo_emulate_prepares = (bool)$this->configCache->get('database', 'pdo_emulate_prepares');
 125
 126                 if (!$this->configCache->get('database', 'disable_pdo') && class_exists('\PDO') && in_array('mysql', PDO::getAvailableDrivers())) {
 127                         $this->driver = self::PDO;
 128                         $connect      = "mysql:host=" . $server . ";dbname=" . $db;
 129
 130                         if ($port > 0) {
 131                                 $connect .= ";port=" . $port;
 132                         }
 133
 134                         if ($charset) {
 135                                 $connect .= ";charset=" . $charset;
 136                         }
 137
 138                         try {
 139                                 $this->connection = @new PDO($connect, $user, $pass, [PDO::ATTR_PERSISTENT => $persistent]);
 140                                 $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->pdo_emulate_prepares);
 141                                 $this->connected = true;
 142                         } catch (PDOException $e) {
 143                                 $this->connected = false;
 144                         }
 145                 }
 146
 147                 if (!$this->connected && class_exists('\mysqli')) {
 148                         $this->driver = self::MYSQLI;
 149
 150                         if ($port > 0) {
 151                                 $this->connection = @new mysqli($server, $user, $pass, $db, $port);
 152                         } else {
 153                                 $this->connection = @new mysqli($server, $user, $pass, $db);
 154                         }
 155
 156                         if (!mysqli_connect_errno()) {
 157                                 $this->connected = true;
 158
 159                                 if ($charset) {
 160                                         $this->connection->set_charset($charset);
 161                                 }
 162                         }
 163                 }
 164
 165                 // No suitable SQL driver was found.
 166                 if (!$this->connected) {
 167                         $this->driver     = null;
 168                         $this->connection = null;
 169                 }
 170
 171                 return $this->connected;
 172         }
 173
 174         public function setTestmode(bool $test)
 175         {
 176                 $this->testmode = $test;
 177         }
 178         /**
 179          * Sets the logger for DBA
 180          *
 181          * @note this is necessary because if we want to load the logger configuration
 182          *       from the DB, but there's an error, we would print out an exception.
 183          *       So the logger gets updated after the logger configuration can be retrieved
 184          *       from the database
 185          *
 186          * @param LoggerInterface $logger
 187          */
 188         public function setLogger(LoggerInterface $logger)
 189         {
 190                 $this->logger = $logger;
 191         }
 192
 193         /**
 194          * Sets the profiler for DBA
 195          *
 196          * @param Profiler $profiler
 197          */
 198         public function setProfiler(Profiler $profiler)
 199         {
 200                 $this->profiler = $profiler;
 201         }
 202         /**
 203          * Disconnects the current database connection
 204          */
 205         public function disconnect()
 206         {
 207                 if (!is_null($this->connection)) {
 208                         switch ($this->driver) {
 209                                 case self::PDO:
 210                                         $this->connection = null;
 211                                         break;
 212                                 case self::MYSQLI:
 213                                         $this->connection->close();
 214                                         $this->connection = null;
 215                                         break;
 216                         }
 217                 }
 218
 219                 $this->driver    = null;
 220                 $this->connected = false;
 221         }
 222
 223         /**
 224          * Perform a reconnect of an existing database connection
 225          */
 226         public function reconnect()
 227         {
 228                 $this->disconnect();
 229                 return $this->connect();
 230         }
 231
 232         /**
 233          * Return the database object.
 234          *
 235          * @return PDO|mysqli
 236          */
 237         public function getConnection()
 238         {
 239                 return $this->connection;
 240         }
 241
 242         /**
 243          * Return the database driver string
 244          *
 245          * @return string with either "pdo" or "mysqli"
 246          */
 247         public function getDriver()
 248         {
 249                 return $this->driver;
 250         }
 251
 252         /**
 253          * Returns the MySQL server version string
 254          *
 255          * This function discriminate between the deprecated mysql API and the current
 256          * object-oriented mysqli API. Example of returned string: 5.5.46-0+deb8u1
 257          *
 258          * @return string
 259          */
 260         public function serverInfo()
 261         {
 262                 if ($this->server_info == '') {
 263                         switch ($this->driver) {
 264                                 case self::PDO:
 265                                         $this->server_info = $this->connection->getAttribute(PDO::ATTR_SERVER_VERSION);
 266                                         break;
 267                                 case self::MYSQLI:
 268                                         $this->server_info = $this->connection->server_info;
 269                                         break;
 270                         }
 271                 }
 272                 return $this->server_info;
 273         }
 274
 275         /**
 276          * Returns the selected database name
 277          *
 278          * @return string
 279          * @throws \Exception
 280          */
 281         public function databaseName()
 282         {
 283                 $ret  = $this->p("SELECT DATABASE() AS `db`");
 284                 $data = $this->toArray($ret);
 285                 return $data[0]['db'];
 286         }
 287
 288         /**
 289          * Analyze a database query and log this if some conditions are met.
 290          *
 291          * @param string $query The database query that will be analyzed
 292          *
 293          * @throws \Exception
 294          */
 295         private function logIndex($query)
 296         {
 297
 298                 if (!$this->configCache->get('system', 'db_log_index')) {
 299                         return;
 300                 }
 301
 302                 // Don't explain an explain statement
 303                 if (strtolower(substr($query, 0, 7)) == "explain") {
 304                         return;
 305                 }
 306
 307                 // Only do the explain on "select", "update" and "delete"
 308                 if (!in_array(strtolower(substr($query, 0, 6)), ["select", "update", "delete"])) {
 309                         return;
 310                 }
 311
 312                 $r = $this->p("EXPLAIN " . $query);
 313                 if (!$this->isResult($r)) {
 314                         return;
 315                 }
 316
 317                 $watchlist = explode(',', $this->configCache->get('system', 'db_log_index_watch'));
 318                 $denylist = explode(',', $this->configCache->get('system', 'db_log_index_denylist'));
 319
 320                 while ($row = $this->fetch($r)) {
 321                         if ((intval($this->configCache->get('system', 'db_loglimit_index')) > 0)) {
 322                                 $log = (in_array($row['key'], $watchlist) &&
 323                                         ($row['rows'] >= intval($this->configCache->get('system', 'db_loglimit_index'))));
 324                         } else {
 325                                 $log = false;
 326                         }
 327
 328                         if ((intval($this->configCache->get('system', 'db_loglimit_index_high')) > 0) && ($row['rows'] >= intval($this->configCache->get('system', 'db_loglimit_index_high')))) {
 329                                 $log = true;
 330                         }
 331
 332                         if (in_array($row['key'], $denylist) || ($row['key'] == "")) {
 333                                 $log = false;
 334                         }
 335
 336                         if ($log) {
 337                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 338                                 @file_put_contents($this->configCache->get('system', 'db_log_index'), DateTimeFormat::utcNow() . "\t" .
 339                                                                                                       $row['key'] . "\t" . $row['rows'] . "\t" . $row['Extra'] . "\t" .
 340                                                                                                       basename($backtrace[1]["file"]) . "\t" .
 341                                                                                                       $backtrace[1]["line"] . "\t" . $backtrace[2]["function"] . "\t" .
 342                                                                                                       substr($query, 0, 4000) . "\n", FILE_APPEND);
 343                         }
 344                 }
 345         }
 346
 347         /**
 348          * Removes every not allowlisted character from the identifier string
 349          *
 350          * @param string $identifier
 351          *
 352          * @return string sanitized identifier
 353          * @throws \Exception
 354          */
 355         private function sanitizeIdentifier($identifier)
 356         {
 357                 return preg_replace('/[^A-Za-z0-9_\-]+/', '', $identifier);
 358         }
 359
 360         public function escape($str)
 361         {
 362                 if ($this->connected) {
 363                         switch ($this->driver) {
 364                                 case self::PDO:
 365                                         return substr(@$this->connection->quote($str, PDO::PARAM_STR), 1, -1);
 366
 367                                 case self::MYSQLI:
 368                                         return @$this->connection->real_escape_string($str);
 369                         }
 370                 } else {
 371                         return str_replace("'", "\\'", $str);
 372                 }
 373         }
 374
 375         public function isConnected()
 376         {
 377                 return $this->connected;
 378         }
 379
 380         public function connected()
 381         {
 382                 $connected = false;
 383
 384                 if (is_null($this->connection)) {
 385                         return false;
 386                 }
 387
 388                 switch ($this->driver) {
 389                         case self::PDO:
 390                                 $r = $this->p("SELECT 1");
 391                                 if ($this->isResult($r)) {
 392                                         $row       = $this->toArray($r);
 393                                         $connected = ($row[0]['1'] == '1');
 394                                 }
 395                                 break;
 396                         case self::MYSQLI:
 397                                 $connected = $this->connection->ping();
 398                                 break;
 399                 }
 400
 401                 return $connected;
 402         }
 403
 404         /**
 405          * Replaces ANY_VALUE() function by MIN() function,
 406          * if the database server does not support ANY_VALUE().
 407          *
 408          * Considerations for Standard SQL, or MySQL with ONLY_FULL_GROUP_BY (default since 5.7.5).
 409          * ANY_VALUE() is available from MySQL 5.7.5 https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html
 410          * A standard fall-back is to use MIN().
 411          *
 412          * @param string $sql An SQL string without the values
 413          *
 414          * @return string The input SQL string modified if necessary.
 415          */
 416         public function anyValueFallback($sql)
 417         {
 418                 $server_info = $this->serverInfo();
 419                 if (version_compare($server_info, '5.7.5', '<') ||
 420                     (stripos($server_info, 'MariaDB') !== false)) {
 421                         $sql = str_ireplace('ANY_VALUE(', 'MIN(', $sql);
 422                 }
 423                 return $sql;
 424         }
 425
 426         /**
 427          * Replaces the ? placeholders with the parameters in the $args array
 428          *
 429          * @param string $sql  SQL query
 430          * @param array  $args The parameters that are to replace the ? placeholders
 431          *
 432          * @return string The replaced SQL query
 433          */
 434         private function replaceParameters($sql, $args)
 435         {
 436                 $offset = 0;
 437                 foreach ($args AS $param => $value) {
 438                         if (is_int($args[$param]) || is_float($args[$param]) || is_bool($args[$param])) {
 439                                 $replace = intval($args[$param]);
 440                         } elseif (is_null($args[$param])) {
 441                                 $replace = 'NULL';
 442                         } else {
 443                                 $replace = "'" . $this->escape($args[$param]) . "'";
 444                         }
 445
 446                         $pos = strpos($sql, '?', $offset);
 447                         if ($pos !== false) {
 448                                 $sql = substr_replace($sql, $replace, $pos, 1);
 449                         }
 450                         $offset = $pos + strlen($replace);
 451                 }
 452                 return $sql;
 453         }
 454
 455         /**
 456          * Executes a prepared statement that returns data
 457          *
 458          * @usage Example: $r = p("SELECT * FROM `post` WHERE `guid` = ?", $guid);
 459          *
 460          * Please only use it with complicated queries.
 461          * For all regular queries please use DBA::select or DBA::exists
 462          *
 463          * @param string $sql SQL statement
 464          *
 465          * @return bool|object statement object or result object
 466          * @throws \Exception
 467          */
 468         public function p($sql)
 469         {
 470
 471                 $stamp1 = microtime(true);
 472
 473                 $params = DBA::getParam(func_get_args());
 474
 475                 // Renumber the array keys to be sure that they fit
 476                 $i    = 0;
 477                 $args = [];
 478                 foreach ($params AS $param) {
 479                         // Avoid problems with some MySQL servers and boolean values. See issue #3645
 480                         if (is_bool($param)) {
 481                                 $param = (int)$param;
 482                         }
 483                         $args[++$i] = $param;
 484                 }
 485
 486                 if (!$this->connected) {
 487                         return false;
 488                 }
 489
 490                 if ((substr_count($sql, '?') != count($args)) && (count($args) > 0)) {
 491                         // Question: Should we continue or stop the query here?
 492                         $this->logger->warning('Query parameters mismatch.', ['query' => $sql, 'args' => $args, 'callstack' => System::callstack()]);
 493                 }
 494
 495                 $sql = DBA::cleanQuery($sql);
 496                 $sql = $this->anyValueFallback($sql);
 497
 498                 $orig_sql = $sql;
 499
 500                 if ($this->configCache->get('system', 'db_callstack') !== null) {
 501                         $sql = "/*" . System::callstack() . " */ " . $sql;
 502                 }
 503
 504                 $is_error            = false;
 505                 $this->error         = '';
 506                 $this->errorno       = 0;
 507                 $this->affected_rows = 0;
 508
 509                 // We have to make some things different if this function is called from "e"
 510                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
 511
 512                 if (isset($trace[1])) {
 513                         $called_from = $trace[1];
 514                 } else {
 515                         // We use just something that is defined to avoid warnings
 516                         $called_from = $trace[0];
 517                 }
 518                 // We are having an own error logging in the function "e"
 519                 $called_from_e = ($called_from['function'] == 'e');
 520
 521                 if (!isset($this->connection)) {
 522                         throw new InternalServerErrorException('The Connection is empty, although connected is set true.');
 523                 }
 524
 525                 switch ($this->driver) {
 526                         case self::PDO:
 527                                 // If there are no arguments we use "query"
 528                                 if (count($args) == 0) {
 529                                         if (!$retval = $this->connection->query($this->replaceParameters($sql, $args))) {
 530                                                 $errorInfo     = $this->connection->errorInfo();
 531                                                 $this->error   = $errorInfo[2];
 532                                                 $this->errorno = $errorInfo[1];
 533                                                 $retval        = false;
 534                                                 $is_error      = true;
 535                                                 break;
 536                                         }
 537                                         $this->affected_rows = $retval->rowCount();
 538                                         break;
 539                                 }
 540
 541                                 /** @var $stmt mysqli_stmt|PDOStatement */
 542                                 if (!$stmt = $this->connection->prepare($sql)) {
 543                                         $errorInfo     = $this->connection->errorInfo();
 544                                         $this->error   = $errorInfo[2];
 545                                         $this->errorno = $errorInfo[1];
 546                                         $retval        = false;
 547                                         $is_error      = true;
 548                                         break;
 549                                 }
 550
 551                                 foreach ($args AS $param => $value) {
 552                                         if (is_int($args[$param])) {
 553                                                 $data_type = PDO::PARAM_INT;
 554                                         } else {
 555                                                 $data_type = PDO::PARAM_STR;
 556                                         }
 557                                         $stmt->bindParam($param, $args[$param], $data_type);
 558                                 }
 559
 560                                 if (!$stmt->execute()) {
 561                                         $errorInfo     = $stmt->errorInfo();
 562                                         $this->error   = $errorInfo[2];
 563                                         $this->errorno = $errorInfo[1];
 564                                         $retval        = false;
 565                                         $is_error      = true;
 566                                 } else {
 567                                         $retval              = $stmt;
 568                                         $this->affected_rows = $retval->rowCount();
 569                                 }
 570                                 break;
 571                         case self::MYSQLI:
 572                                 // There are SQL statements that cannot be executed with a prepared statement
 573                                 $parts           = explode(' ', $orig_sql);
 574                                 $command         = strtolower($parts[0]);
 575                                 $can_be_prepared = in_array($command, ['select', 'update', 'insert', 'delete']);
 576
 577                                 // The fallback routine is called as well when there are no arguments
 578                                 if (!$can_be_prepared || (count($args) == 0)) {
 579                                         $retval = $this->connection->query($this->replaceParameters($sql, $args));
 580                                         if ($this->connection->errno) {
 581                                                 $this->error   = $this->connection->error;
 582                                                 $this->errorno = $this->connection->errno;
 583                                                 $retval        = false;
 584                                                 $is_error      = true;
 585                                         } else {
 586                                                 if (isset($retval->num_rows)) {
 587                                                         $this->affected_rows = $retval->num_rows;
 588                                                 } else {
 589                                                         $this->affected_rows = $this->connection->affected_rows;
 590                                                 }
 591                                         }
 592                                         break;
 593                                 }
 594
 595                                 $stmt = $this->connection->stmt_init();
 596
 597                                 if (!$stmt->prepare($sql)) {
 598                                         $this->error   = $stmt->error;
 599                                         $this->errorno = $stmt->errno;
 600                                         $retval        = false;
 601                                         $is_error      = true;
 602                                         break;
 603                                 }
 604
 605                                 $param_types = '';
 606                                 $values      = [];
 607                                 foreach ($args AS $param => $value) {
 608                                         if (is_int($args[$param])) {
 609                                                 $param_types .= 'i';
 610                                         } elseif (is_float($args[$param])) {
 611                                                 $param_types .= 'd';
 612                                         } elseif (is_string($args[$param])) {
 613                                                 $param_types .= 's';
 614                                         } else {
 615                                                 $param_types .= 'b';
 616                                         }
 617                                         $values[] = &$args[$param];
 618                                 }
 619
 620                                 if (count($values) > 0) {
 621                                         array_unshift($values, $param_types);
 622                                         call_user_func_array([$stmt, 'bind_param'], $values);
 623                                 }
 624
 625                                 if (!$stmt->execute()) {
 626                                         $this->error   = $this->connection->error;
 627                                         $this->errorno = $this->connection->errno;
 628                                         $retval        = false;
 629                                         $is_error      = true;
 630                                 } else {
 631                                         $stmt->store_result();
 632                                         $retval              = $stmt;
 633                                         $this->affected_rows = $retval->affected_rows;
 634                                 }
 635                                 break;
 636                 }
 637
 638                 // See issue https://github.com/friendica/friendica/issues/8572
 639                 // Ensure that we always get an error message on an error.
 640                 if ($is_error && empty($this->errorno)) {
 641                         $this->errorno = -1;
 642                 }
 643
 644                 if ($is_error && empty($this->error)) {
 645                         $this->error = 'Unknown database error';
 646                 }
 647
 648                 // We are having an own error logging in the function "e"
 649                 if (($this->errorno != 0) && !$called_from_e) {
 650                         // We have to preserve the error code, somewhere in the logging it get lost
 651                         $error   = $this->error;
 652                         $errorno = $this->errorno;
 653
 654                         if ($this->testmode) {
 655                                 throw new DatabaseException($error, $errorno, $this->replaceParameters($sql, $args));
 656                         }
 657
 658                         $this->logger->error('DB Error', [
 659                                 'code'      => $errorno,
 660                                 'error'     => $error,
 661                                 'callstack' => System::callstack(8),
 662                                 'params'    => $this->replaceParameters($sql, $args),
 663                         ]);
 664
 665                         // On a lost connection we try to reconnect - but only once.
 666                         if ($errorno == 2006) {
 667                                 if ($this->in_retrial || !$this->reconnect()) {
 668                                         // It doesn't make sense to continue when the database connection was lost
 669                                         if ($this->in_retrial) {
 670                                                 $this->logger->notice('Giving up retrial because of database error', [
 671                                                         'code'  => $errorno,
 672                                                         'error' => $error,
 673                                                 ]);
 674                                         } else {
 675                                                 $this->logger->notice('Couldn\'t reconnect after database error', [
 676                                                         'code'  => $errorno,
 677                                                         'error' => $error,
 678                                                 ]);
 679                                         }
 680                                         exit(1);
 681                                 } else {
 682                                         // We try it again
 683                                         $this->logger->notice('Reconnected after database error', [
 684                                                 'code'  => $errorno,
 685                                                 'error' => $error,
 686                                         ]);
 687                                         $this->in_retrial = true;
 688                                         $ret              = $this->p($sql, $args);
 689                                         $this->in_retrial = false;
 690                                         return $ret;
 691                                 }
 692                         }
 693
 694                         $this->error   = $error;
 695                         $this->errorno = $errorno;
 696                 }
 697
 698                 $this->profiler->saveTimestamp($stamp1, 'database');
 699
 700                 if ($this->configCache->get('system', 'db_log')) {
 701                         $stamp2   = microtime(true);
 702                         $duration = (float)($stamp2 - $stamp1);
 703
 704                         if (($duration > $this->configCache->get('system', 'db_loglimit'))) {
 705                                 $duration  = round($duration, 3);
 706                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 707
 708                                 @file_put_contents($this->configCache->get('system', 'db_log'), DateTimeFormat::utcNow() . "\t" . $duration . "\t" .
 709                                                                                                 basename($backtrace[1]["file"]) . "\t" .
 710                                                                                                 $backtrace[1]["line"] . "\t" . $backtrace[2]["function"] . "\t" .
 711                                                                                                 substr($this->replaceParameters($sql, $args), 0, 4000) . "\n", FILE_APPEND);
 712                         }
 713                 }
 714                 return $retval;
 715         }
 716
 717         /**
 718          * Executes a prepared statement like UPDATE or INSERT that doesn't return data
 719          *
 720          * Please use DBA::delete, DBA::insert, DBA::update, ... instead
 721          *
 722          * @param string $sql SQL statement
 723          *
 724          * @return boolean Was the query successfull? False is returned only if an error occurred
 725          * @throws \Exception
 726          */
 727         public function e($sql)
 728         {
 729
 730                 $stamp = microtime(true);
 731
 732                 $params = DBA::getParam(func_get_args());
 733
 734                 // In a case of a deadlock we are repeating the query 20 times
 735                 $timeout = 20;
 736
 737                 do {
 738                         $stmt = $this->p($sql, $params);
 739
 740                         if (is_bool($stmt)) {
 741                                 $retval = $stmt;
 742                         } elseif (is_object($stmt)) {
 743                                 $retval = true;
 744                         } else {
 745                                 $retval = false;
 746                         }
 747
 748                         $this->close($stmt);
 749
 750                 } while (($this->errorno == 1213) && (--$timeout > 0));
 751
 752                 if ($this->errorno != 0) {
 753                         // We have to preserve the error code, somewhere in the logging it get lost
 754                         $error   = $this->error;
 755                         $errorno = $this->errorno;
 756
 757                         if ($this->testmode) {
 758                                 throw new DatabaseException($error, $errorno, $this->replaceParameters($sql, $params));
 759                         }
 760
 761                         $this->logger->error('DB Error', [
 762                                 'code'      => $errorno,
 763                                 'error'     => $error,
 764                                 'callstack' => System::callstack(8),
 765                                 'params'    => $this->replaceParameters($sql, $params),
 766                         ]);
 767
 768                         // On a lost connection we simply quit.
 769                         // A reconnect like in $this->p could be dangerous with modifications
 770                         if ($errorno == 2006) {
 771                                 $this->logger->notice('Giving up because of database error', [
 772                                         'code'  => $errorno,
 773                                         'error' => $error,
 774                                 ]);
 775                                 exit(1);
 776                         }
 777
 778                         $this->error   = $error;
 779                         $this->errorno = $errorno;
 780                 }
 781
 782                 $this->profiler->saveTimestamp($stamp, "database_write");
 783
 784                 return $retval;
 785         }
 786
 787         /**
 788          * Check if data exists
 789          *
 790          * @param string|array $table     Table name or array [schema => table]
 791          * @param array        $condition array of fields for condition
 792          *
 793          * @return boolean Are there rows for that condition?
 794          * @throws \Exception
 795          */
 796         public function exists($table, $condition)
 797         {
 798                 if (empty($table)) {
 799                         return false;
 800                 }
 801
 802                 $fields = [];
 803
 804                 if (empty($condition)) {
 805                         return DBStructure::existsTable($table);
 806                 }
 807
 808                 reset($condition);
 809                 $first_key = key($condition);
 810                 if (!is_int($first_key)) {
 811                         $fields = [$first_key];
 812                 }
 813
 814                 $stmt = $this->select($table, $fields, $condition, ['limit' => 1]);
 815
 816                 if (is_bool($stmt)) {
 817                         $retval = $stmt;
 818                 } else {
 819                         $retval = ($this->numRows($stmt) > 0);
 820                 }
 821
 822                 $this->close($stmt);
 823
 824                 return $retval;
 825         }
 826
 827         /**
 828          * Fetches the first row
 829          *
 830          * Please use DBA::selectFirst or DBA::exists whenever this is possible.
 831          *
 832          * Fetches the first row
 833          *
 834          * @param string $sql SQL statement
 835          *
 836          * @return array first row of query
 837          * @throws \Exception
 838          */
 839         public function fetchFirst($sql)
 840         {
 841                 $params = DBA::getParam(func_get_args());
 842
 843                 $stmt = $this->p($sql, $params);
 844
 845                 if (is_bool($stmt)) {
 846                         $retval = $stmt;
 847                 } else {
 848                         $retval = $this->fetch($stmt);
 849                 }
 850
 851                 $this->close($stmt);
 852
 853                 return $retval;
 854         }
 855
 856         /**
 857          * Returns the number of affected rows of the last statement
 858          *
 859          * @return int Number of rows
 860          */
 861         public function affectedRows()
 862         {
 863                 return $this->affected_rows;
 864         }
 865
 866         /**
 867          * Returns the number of columns of a statement
 868          *
 869          * @param object Statement object
 870          *
 871          * @return int Number of columns
 872          */
 873         public function columnCount($stmt)
 874         {
 875                 if (!is_object($stmt)) {
 876                         return 0;
 877                 }
 878                 switch ($this->driver) {
 879                         case self::PDO:
 880                                 return $stmt->columnCount();
 881                         case self::MYSQLI:
 882                                 return $stmt->field_count;
 883                 }
 884                 return 0;
 885         }
 886
 887         /**
 888          * Returns the number of rows of a statement
 889          *
 890          * @param PDOStatement|mysqli_result|mysqli_stmt Statement object
 891          *
 892          * @return int Number of rows
 893          */
 894         public function numRows($stmt)
 895         {
 896                 if (!is_object($stmt)) {
 897                         return 0;
 898                 }
 899                 switch ($this->driver) {
 900                         case self::PDO:
 901                                 return $stmt->rowCount();
 902                         case self::MYSQLI:
 903                                 return $stmt->num_rows;
 904                 }
 905                 return 0;
 906         }
 907
 908         /**
 909          * Fetch a single row
 910          *
 911          * @param PDOStatement|mysqli_stmt $stmt statement object
 912          *
 913          * @return array|false current row
 914          */
 915         public function fetch($stmt)
 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 = $stmt->fetch(PDO::FETCH_ASSOC);
 928                                 if (!empty($stmt->table) && is_array($columns)) {
 929                                         $columns = $this->castFields($stmt->table, $columns);
 930                                 }
 931                                 break;
 932                         case self::MYSQLI:
 933                                 if (get_class($stmt) == 'mysqli_result') {
 934                                         $columns = $stmt->fetch_assoc() ?? false;
 935                                         break;
 936                                 }
 937
 938                                 // This code works, but is slow
 939
 940                                 // Bind the result to a result array
 941                                 $cols = [];
 942
 943                                 $cols_num = [];
 944                                 for ($x = 0; $x < $stmt->field_count; $x++) {
 945                                         $cols[] = &$cols_num[$x];
 946                                 }
 947
 948                                 call_user_func_array([$stmt, 'bind_result'], $cols);
 949
 950                                 if (!$stmt->fetch()) {
 951                                         return false;
 952                                 }
 953
 954                                 // The slow part:
 955                                 // We need to get the field names for the array keys
 956                                 // It seems that there is no better way to do this.
 957                                 $result = $stmt->result_metadata();
 958                                 $fields = $result->fetch_fields();
 959
 960                                 foreach ($cols_num AS $param => $col) {
 961                                         $columns[$fields[$param]->name] = $col;
 962                                 }
 963                 }
 964
 965                 $this->profiler->saveTimestamp($stamp1, 'database');
 966
 967                 return $columns;
 968         }
 969
 970         /**
 971          * Insert a row into a table
 972          *
 973          * @param string|array $table          Table name or array [schema => table]
 974          * @param array        $param          parameter array
 975          * @param int          $duplicate_mode What to do on a duplicated entry
 976          *
 977          * @return boolean was the insert successful?
 978          * @throws \Exception
 979          */
 980         public function insert($table, array $param, int $duplicate_mode = self::INSERT_DEFAULT)
 981         {
 982                 if (empty($table) || empty($param)) {
 983                         $this->logger->info('Table and fields have to be set');
 984                         return false;
 985                 }
 986
 987                 $param = $this->castFields($table, $param);
 988
 989                 $table_string = DBA::buildTableString($table);
 990
 991                 $fields_string = implode(', ', array_map([DBA::class, 'quoteIdentifier'], array_keys($param)));
 992
 993                 $values_string = substr(str_repeat("?, ", count($param)), 0, -2);
 994
 995                 $sql = "INSERT ";
 996
 997                 if ($duplicate_mode == self::INSERT_IGNORE) {
 998                         $sql .= "IGNORE ";
 999                 }
1000
1001                 $sql .= "INTO " . $table_string . " (" . $fields_string . ") VALUES (" . $values_string . ")";
1002
1003                 if ($duplicate_mode == self::INSERT_UPDATE) {
1004                         $fields_string = implode(' = ?, ', array_map([DBA::class, 'quoteIdentifier'], array_keys($param)));
1005
1006                         $sql .= " ON DUPLICATE KEY UPDATE " . $fields_string . " = ?";
1007
1008                         $values = array_values($param);
1009                         $param  = array_merge_recursive($values, $values);
1010                 }
1011
1012                 $result = $this->e($sql, $param);
1013                 if (!$result || ($duplicate_mode != self::INSERT_IGNORE)) {
1014                         return $result;
1015                 }
1016
1017                 return $this->affectedRows() != 0;
1018         }
1019
1020         /**
1021          * Inserts a row with the provided data in the provided table.
1022          * If the data corresponds to an existing row through a UNIQUE or PRIMARY index constraints, it updates the row instead.
1023          *
1024          * @param string|array $table Table name or array [schema => table]
1025          * @param array        $param parameter array
1026          *
1027          * @return boolean was the insert successful?
1028          * @throws \Exception
1029          */
1030         public function replace($table, array $param)
1031         {
1032                 if (empty($table) || empty($param)) {
1033                         $this->logger->info('Table and fields have to be set');
1034                         return false;
1035                 }
1036
1037                 $param = $this->castFields($table, $param);
1038
1039                 $table_string = DBA::buildTableString($table);
1040
1041                 $fields_string = implode(', ', array_map([DBA::class, 'quoteIdentifier'], array_keys($param)));
1042
1043                 $values_string = substr(str_repeat("?, ", count($param)), 0, -2);
1044
1045                 $sql = "REPLACE " . $table_string . " (" . $fields_string . ") VALUES (" . $values_string . ")";
1046
1047                 return $this->e($sql, $param);
1048         }
1049
1050         /**
1051          * Fetch the id of the last insert command
1052          *
1053          * @return integer Last inserted id
1054          */
1055         public function lastInsertId()
1056         {
1057                 switch ($this->driver) {
1058                         case self::PDO:
1059                                 $id = $this->connection->lastInsertId();
1060                                 break;
1061                         case self::MYSQLI:
1062                                 $id = $this->connection->insert_id;
1063                                 break;
1064                 }
1065                 return (int)$id;
1066         }
1067
1068         /**
1069          * Locks a table for exclusive write access
1070          *
1071          * This function can be extended in the future to accept a table array as well.
1072          *
1073          * @param string|array $table Table name or array [schema => table]
1074          *
1075          * @return boolean was the lock successful?
1076          * @throws \Exception
1077          */
1078         public function lock($table)
1079         {
1080                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
1081                 if ($this->driver == self::PDO) {
1082                         $this->e("SET autocommit=0");
1083                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
1084                 } else {
1085                         $this->connection->autocommit(false);
1086                 }
1087
1088                 $success = $this->e("LOCK TABLES " . DBA::buildTableString($table) . " WRITE");
1089
1090                 if ($this->driver == self::PDO) {
1091                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->pdo_emulate_prepares);
1092                 }
1093
1094                 if (!$success) {
1095                         if ($this->driver == self::PDO) {
1096                                 $this->e("SET autocommit=1");
1097                         } else {
1098                                 $this->connection->autocommit(true);
1099                         }
1100                 } else {
1101                         $this->in_transaction = true;
1102                 }
1103                 return $success;
1104         }
1105
1106         /**
1107          * Unlocks all locked tables
1108          *
1109          * @return boolean was the unlock successful?
1110          * @throws \Exception
1111          */
1112         public function unlock()
1113         {
1114                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
1115                 $this->performCommit();
1116
1117                 if ($this->driver == self::PDO) {
1118                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
1119                 }
1120
1121                 $success = $this->e("UNLOCK TABLES");
1122
1123                 if ($this->driver == self::PDO) {
1124                         $this->connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->pdo_emulate_prepares);
1125                         $this->e("SET autocommit=1");
1126                 } else {
1127                         $this->connection->autocommit(true);
1128                 }
1129
1130                 $this->in_transaction = false;
1131                 return $success;
1132         }
1133
1134         /**
1135          * Starts a transaction
1136          *
1137          * @return boolean Was the command executed successfully?
1138          */
1139         public function transaction()
1140         {
1141                 if (!$this->performCommit()) {
1142                         return false;
1143                 }
1144
1145                 switch ($this->driver) {
1146                         case self::PDO:
1147                                 if (!$this->connection->inTransaction() && !$this->connection->beginTransaction()) {
1148                                         return false;
1149                                 }
1150                                 break;
1151
1152                         case self::MYSQLI:
1153                                 if (!$this->connection->begin_transaction()) {
1154                                         return false;
1155                                 }
1156                                 break;
1157                 }
1158
1159                 $this->in_transaction = true;
1160                 return true;
1161         }
1162
1163         protected function performCommit()
1164         {
1165                 switch ($this->driver) {
1166                         case self::PDO:
1167                                 if (!$this->connection->inTransaction()) {
1168                                         return true;
1169                                 }
1170
1171                                 return $this->connection->commit();
1172
1173                         case self::MYSQLI:
1174                                 return $this->connection->commit();
1175                 }
1176
1177                 return true;
1178         }
1179
1180         /**
1181          * Does a commit
1182          *
1183          * @return boolean Was the command executed successfully?
1184          */
1185         public function commit()
1186         {
1187                 if (!$this->performCommit()) {
1188                         return false;
1189                 }
1190                 $this->in_transaction = false;
1191                 return true;
1192         }
1193
1194         /**
1195          * Does a rollback
1196          *
1197          * @return boolean Was the command executed successfully?
1198          */
1199         public function rollback()
1200         {
1201                 $ret = false;
1202
1203                 switch ($this->driver) {
1204                         case self::PDO:
1205                                 if (!$this->connection->inTransaction()) {
1206                                         $ret = true;
1207                                         break;
1208                                 }
1209                                 $ret = $this->connection->rollBack();
1210                                 break;
1211
1212                         case self::MYSQLI:
1213                                 $ret = $this->connection->rollback();
1214                                 break;
1215                 }
1216                 $this->in_transaction = false;
1217                 return $ret;
1218         }
1219
1220         /**
1221          * Build the array with the table relations
1222          *
1223          * The array is build from the database definitions in DBStructure.php
1224          *
1225          * This process must only be started once, since the value is cached.
1226          */
1227         private function buildRelationData()
1228         {
1229                 $definition = DBStructure::definition($this->configCache->get('system', 'basepath'));
1230
1231                 foreach ($definition AS $table => $structure) {
1232                         foreach ($structure['fields'] AS $field => $field_struct) {
1233                                 if (isset($field_struct['relation'])) {
1234                                         foreach ($field_struct['relation'] AS $rel_table => $rel_field) {
1235                                                 $this->relation[$rel_table][$rel_field][$table][] = $field;
1236                                         }
1237                                 }
1238                         }
1239                 }
1240         }
1241
1242         /**
1243          * Delete a row from a table
1244          *
1245          * Note: this methods does NOT accept schema => table arrays because of the complex relation stuff.
1246          *
1247          * @param string $table      Table name
1248          * @param array  $conditions Field condition(s)
1249          * @param array  $options
1250          *                           - cascade: If true we delete records in other tables that depend on the one we're deleting through
1251          *                           relations (default: true)
1252          * @param array  $callstack  Internal use: prevent endless loops
1253          *
1254          * @return boolean was the delete successful?
1255          * @throws \Exception
1256          */
1257         public function delete($table, array $conditions, array $options = [], array &$callstack = [])
1258         {
1259                 if (empty($table) || empty($conditions)) {
1260                         $this->logger->info('Table and conditions have to be set');
1261                         return false;
1262                 }
1263
1264                 $commands = [];
1265
1266                 // Create a key for the loop prevention
1267                 $key = $table . ':' . json_encode($conditions);
1268
1269                 // We quit when this key already exists in the callstack.
1270                 if (isset($callstack[$key])) {
1271                         return true;
1272                 }
1273
1274                 $callstack[$key] = true;
1275
1276                 $commands[$key] = ['table' => $table, 'conditions' => $conditions];
1277
1278                 // Don't use "defaults" here, since it would set "false" to "true"
1279                 if (isset($options['cascade'])) {
1280                         $cascade = $options['cascade'];
1281                 } else {
1282                         $cascade = true;
1283                 }
1284
1285                 // To speed up the whole process we cache the table relations
1286                 if ($cascade && count($this->relation) == 0) {
1287                         $this->buildRelationData();
1288                 }
1289
1290                 // Is there a relation entry for the table?
1291                 if ($cascade && isset($this->relation[$table])) {
1292                         // We only allow a simple "one field" relation.
1293                         $field   = array_keys($this->relation[$table])[0];
1294                         $rel_def = array_values($this->relation[$table])[0];
1295
1296                         // Create a key for preventing double queries
1297                         $qkey = $field . '-' . $table . ':' . json_encode($conditions);
1298
1299                         // When the search field is the relation field, we don't need to fetch the rows
1300                         // This is useful when the leading record is already deleted in the frontend but the rest is done in the backend
1301                         if ((count($conditions) == 1) && ($field == array_keys($conditions)[0])) {
1302                                 foreach ($rel_def AS $rel_table => $rel_fields) {
1303                                         foreach ($rel_fields AS $rel_field) {
1304                                                 $this->delete($rel_table, [$rel_field => array_values($conditions)[0]], $options, $callstack);
1305                                         }
1306                                 }
1307                                 // We quit when this key already exists in the callstack.
1308                         } elseif (!isset($callstack[$qkey])) {
1309                                 $callstack[$qkey] = true;
1310
1311                                 // Fetch all rows that are to be deleted
1312                                 $data = $this->select($table, [$field], $conditions);
1313
1314                                 while ($row = $this->fetch($data)) {
1315                                         $this->delete($table, [$field => $row[$field]], $options, $callstack);
1316                                 }
1317
1318                                 $this->close($data);
1319
1320                                 // Since we had split the delete command we don't need the original command anymore
1321                                 unset($commands[$key]);
1322                         }
1323                 }
1324
1325                 // Now we finalize the process
1326                 $do_transaction = !$this->in_transaction;
1327
1328                 if ($do_transaction) {
1329                         $this->transaction();
1330                 }
1331
1332                 $compacted = [];
1333                 $counter   = [];
1334
1335                 foreach ($commands AS $command) {
1336                         $conditions = $command['conditions'];
1337                         reset($conditions);
1338                         $first_key = key($conditions);
1339
1340                         $condition_string = DBA::buildCondition($conditions);
1341
1342                         if ((count($command['conditions']) > 1) || is_int($first_key)) {
1343                                 $sql = "DELETE FROM " . DBA::quoteIdentifier($command['table']) . " " . $condition_string;
1344                                 $this->logger->info($this->replaceParameters($sql, $conditions), ['callstack' => System::callstack(6), 'internal_callstack' => $callstack]);
1345
1346                                 if (!$this->e($sql, $conditions)) {
1347                                         if ($do_transaction) {
1348                                                 $this->rollback();
1349                                         }
1350                                         return false;
1351                                 }
1352                         } else {
1353                                 $key_table     = $command['table'];
1354                                 $key_condition = array_keys($command['conditions'])[0];
1355                                 $value         = array_values($command['conditions'])[0];
1356
1357                                 // Split the SQL queries in chunks of 100 values
1358                                 // We do the $i stuff here to make the code better readable
1359                                 $i = isset($counter[$key_table][$key_condition]) ? $counter[$key_table][$key_condition] : 0;
1360                                 if (isset($compacted[$key_table][$key_condition][$i]) && count($compacted[$key_table][$key_condition][$i]) > 100) {
1361                                         ++$i;
1362                                 }
1363
1364                                 $compacted[$key_table][$key_condition][$i][$value] = $value;
1365                                 $counter[$key_table][$key_condition]               = $i;
1366                         }
1367                 }
1368                 foreach ($compacted AS $table => $values) {
1369                         foreach ($values AS $field => $field_value_list) {
1370                                 foreach ($field_value_list AS $field_values) {
1371                                         $sql = "DELETE FROM " . DBA::quoteIdentifier($table) . " WHERE " . DBA::quoteIdentifier($field) . " IN (" .
1372                                                substr(str_repeat("?, ", count($field_values)), 0, -2) . ");";
1373
1374                                         $this->logger->info($this->replaceParameters($sql, $field_values), ['callstack' => System::callstack(6), 'internal_callstack' => $callstack]);
1375
1376                                         if (!$this->e($sql, $field_values)) {
1377                                                 if ($do_transaction) {
1378                                                         $this->rollback();
1379                                                 }
1380                                                 return false;
1381                                         }
1382                                 }
1383                         }
1384                 }
1385                 if ($do_transaction) {
1386                         $this->commit();
1387                 }
1388                 return true;
1389         }
1390
1391         /**
1392          * Updates rows
1393          *
1394          * Updates rows in the database. When $old_fields is set to an array,
1395          * the system will only do an update if the fields in that array changed.
1396          *
1397          * Attention:
1398          * Only the values in $old_fields are compared.
1399          * This is an intentional behaviour.
1400          *
1401          * Example:
1402          * We include the timestamp field in $fields but not in $old_fields.
1403          * Then the row will only get the new timestamp when the other fields had changed.
1404          *
1405          * When $old_fields is set to a boolean value the system will do this compare itself.
1406          * When $old_fields is set to "true" the system will do an insert if the row doesn't exists.
1407          *
1408          * Attention:
1409          * Only set $old_fields to a boolean value when you are sure that you will update a single row.
1410          * When you set $old_fields to "true" then $fields must contain all relevant fields!
1411          *
1412          * @param string|array  $table      Table name or array [schema => table]
1413          * @param array         $fields     contains the fields that are updated
1414          * @param array         $condition  condition array with the key values
1415          * @param array|boolean $old_fields array with the old field values that are about to be replaced (true = update on duplicate)
1416          *
1417          * @return boolean was the update successfull?
1418          * @throws \Exception
1419          */
1420         public function update($table, $fields, $condition, $old_fields = [])
1421         {
1422                 if (empty($table) || empty($fields) || empty($condition)) {
1423                         $this->logger->info('Table, fields and condition have to be set');
1424                         return false;
1425                 }
1426
1427                 if (is_bool($old_fields)) {
1428                         $do_insert = $old_fields;
1429
1430                         $old_fields = $this->selectFirst($table, [], $condition);
1431
1432                         if (is_bool($old_fields)) {
1433                                 if ($do_insert) {
1434                                         $values = array_merge($condition, $fields);
1435                                         return $this->replace($table, $values);
1436                                 }
1437                                 $old_fields = [];
1438                         }
1439                 }
1440
1441                 foreach ($old_fields AS $fieldname => $content) {
1442                         if (isset($fields[$fieldname]) && !is_null($content) && ($fields[$fieldname] == $content)) {
1443                                 unset($fields[$fieldname]);
1444                         }
1445                 }
1446
1447                 if (count($fields) == 0) {
1448                         return true;
1449                 }
1450
1451                 $fields = $this->castFields($table, $fields);
1452
1453                 $table_string = DBA::buildTableString($table);
1454
1455                 $condition_string = DBA::buildCondition($condition);
1456
1457                 $sql = "UPDATE " . $table_string . " SET "
1458                         . implode(" = ?, ", array_map([DBA::class, 'quoteIdentifier'], array_keys($fields))) . " = ?"
1459                         . $condition_string;
1460
1461                 // Combines the updated fields parameter values with the condition parameter values
1462                 $params  = array_merge(array_values($fields), $condition);
1463
1464                 return $this->e($sql, $params);
1465         }
1466
1467         /**
1468          * Retrieve a single record from a table and returns it in an associative array
1469          *
1470          * @param string|array $table
1471          * @param array        $fields
1472          * @param array        $condition
1473          * @param array        $params
1474          *
1475          * @return bool|array
1476          * @throws \Exception
1477          * @see   $this->select
1478          */
1479         public function selectFirst($table, array $fields = [], array $condition = [], $params = [])
1480         {
1481                 $params['limit'] = 1;
1482                 $result          = $this->select($table, $fields, $condition, $params);
1483
1484                 if (is_bool($result)) {
1485                         return $result;
1486                 } else {
1487                         $row = $this->fetch($result);
1488                         $this->close($result);
1489                         return $row;
1490                 }
1491         }
1492
1493         /**
1494          * Select rows from a table and fills an array with the data
1495          *
1496          * @param string|array $table     Table name or array [schema => table]
1497          * @param array        $fields    Array of selected fields, empty for all
1498          * @param array        $condition Array of fields for condition
1499          * @param array        $params    Array of several parameters
1500          *
1501          * @return array Data array
1502          * @throws \Exception
1503          * @see   self::select
1504          */
1505         public function selectToArray($table, array $fields = [], array $condition = [], array $params = [])
1506         {
1507                 return $this->toArray($this->select($table, $fields, $condition, $params));
1508         }
1509
1510         /**
1511          * Select rows from a table
1512          *
1513          *
1514          * Example:
1515          * $table = 'post';
1516          * or:
1517          * $table = ['schema' => 'table'];
1518          * @see DBA::buildTableString()
1519          *
1520          * $fields = ['id', 'uri', 'uid', 'network'];
1521          *
1522          * $condition = ['uid' => 1, 'network' => 'dspr', 'blocked' => true];
1523          * or:
1524          * $condition = ['`uid` = ? AND `network` IN (?, ?)', 1, 'dfrn', 'dspr'];
1525          * @see DBA::buildCondition()
1526          *
1527          * $params = ['order' => ['id', 'received' => true, 'created' => 'ASC'), 'limit' => 10];
1528          * @see DBA::buildParameter()
1529          *
1530          * $data = DBA::select($table, $fields, $condition, $params);
1531          *
1532          * @param string|array $table     Table name or array [schema => table]
1533          * @param array        $fields    Array of selected fields, empty for all
1534          * @param array        $condition Array of fields for condition
1535          * @param array        $params    Array of several parameters
1536          * @return boolean|object
1537          * @throws \Exception
1538          */
1539         public function select($table, array $fields = [], array $condition = [], array $params = [])
1540         {
1541                 if (empty($table)) {
1542                         return false;
1543                 }
1544
1545                 if (count($fields) > 0) {
1546                         $select_string = implode(', ', array_map([DBA::class, 'quoteIdentifier'], $fields));
1547                 } else {
1548                         $select_string = '*';
1549                 }
1550
1551                 $table_string = DBA::buildTableString($table);
1552
1553                 $condition_string = DBA::buildCondition($condition);
1554
1555                 $param_string = DBA::buildParameter($params);
1556
1557                 $sql = "SELECT " . $select_string . " FROM " . $table_string . $condition_string . $param_string;
1558
1559                 $result = $this->p($sql, $condition);
1560
1561                 if (($this->driver == self::PDO) && !empty($result) && is_string($table)) {
1562                         $result->table = $table;
1563                 }
1564
1565                 return $result;
1566         }
1567
1568         /**
1569          * Counts the rows from a table satisfying the provided condition
1570          *
1571          * @param string|array $table     Table name or array [schema => table]
1572          * @param array        $condition Array of fields for condition
1573          * @param array        $params    Array of several parameters
1574          *
1575          * @return int
1576          *
1577          * Example:
1578          * $table = "post";
1579          *
1580          * $condition = ["uid" => 1, "network" => 'dspr'];
1581          * or:
1582          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1583          *
1584          * $count = DBA::count($table, $condition);
1585          * @throws \Exception
1586          */
1587         public function count($table, array $condition = [], array $params = [])
1588         {
1589                 if (empty($table)) {
1590                         return false;
1591                 }
1592
1593                 $table_string = DBA::buildTableString($table);
1594
1595                 $condition_string = DBA::buildCondition($condition);
1596
1597                 if (empty($params['expression'])) {
1598                         $expression = '*';
1599                 } elseif (!empty($params['distinct'])) {
1600                         $expression = "DISTINCT " . DBA::quoteIdentifier($params['expression']);
1601                 } else {
1602                         $expression = DBA::quoteIdentifier($params['expression']);
1603                 }
1604
1605                 $sql = "SELECT COUNT(" . $expression . ") AS `count` FROM " . $table_string . $condition_string;
1606
1607                 $row = $this->fetchFirst($sql, $condition);
1608
1609                 // Ensure to always return either a "null" or a numeric value
1610                 return is_numeric($row['count']) ? (int)$row['count'] : $row['count'];
1611         }
1612
1613         /**
1614          * Fills an array with data from a query
1615          *
1616          * @param object $stmt     statement object
1617          * @param bool   $do_close Close database connection after last row
1618          * @param int    $count    maximum number of rows to be fetched
1619          *
1620          * @return array Data array
1621          */
1622         public function toArray($stmt, $do_close = true, int $count = 0)
1623         {
1624                 if (is_bool($stmt)) {
1625                         return [];
1626                 }
1627
1628                 $data = [];
1629                 while ($row = $this->fetch($stmt)) {
1630                         $data[] = $row;
1631                         if (($count != 0) && (count($data) == $count)) {
1632                                 return $data;
1633                         }
1634                 }
1635
1636                 if ($do_close) {
1637                         $this->close($stmt);
1638                 }
1639
1640                 return $data;
1641         }
1642
1643         /**
1644          * Cast field types according to the table definition
1645          *
1646          * @param string $table
1647          * @param array  $fields
1648          * @return array casted fields
1649          */
1650         public function castFields(string $table, array $fields) {
1651                 // When there is no data, we don't need to do something
1652                 if (empty($fields)) {
1653                         return $fields;
1654                 }
1655
1656                 // We only need to cast fields with PDO
1657                 if ($this->driver != self::PDO) {
1658                         return $fields;
1659                 }
1660
1661                 // We only need to cast when emulating the prepares
1662                 if (!$this->connection->getAttribute(PDO::ATTR_EMULATE_PREPARES)) {
1663                         return $fields;
1664                 }
1665
1666                 $types = [];
1667
1668                 $tables = DBStructure::definition('', false);
1669                 if (empty($tables[$table])) {
1670                         // When a matching table wasn't found we check if it is a view
1671                         $views = View::definition('', false);
1672                         if (empty($views[$table])) {
1673                                 return $fields;
1674                         }
1675
1676                         foreach(array_keys($fields) as $field) {
1677                                 if (!empty($views[$table]['fields'][$field])) {
1678                                         $viewdef = $views[$table]['fields'][$field];
1679                                         if (!empty($tables[$viewdef[0]]['fields'][$viewdef[1]]['type'])) {
1680                                                 $types[$field] = $tables[$viewdef[0]]['fields'][$viewdef[1]]['type'];
1681                                         }
1682                                 }
1683                         }
1684                 } else {
1685                         foreach ($tables[$table]['fields'] as $field => $definition) {
1686                                 $types[$field] = $definition['type'];
1687                         }
1688                 }
1689
1690                 foreach ($fields as $field => $content) {
1691                         if (is_null($content) || empty($types[$field])) {
1692                                 continue;
1693                         }
1694
1695                         if ((substr($types[$field], 0, 7) == 'tinyint') || (substr($types[$field], 0, 8) == 'smallint') ||
1696                                 (substr($types[$field], 0, 9) == 'mediumint') || (substr($types[$field], 0, 3) == 'int') ||
1697                                 (substr($types[$field], 0, 6) == 'bigint') || (substr($types[$field], 0, 7) == 'boolean')) {
1698                                 $fields[$field] = (int)$content;
1699                         }
1700                         if ((substr($types[$field], 0, 5) == 'float') || (substr($types[$field], 0, 6) == 'double')) {
1701                                 $fields[$field] = (float)$content;
1702                         }
1703                 }
1704
1705                 return $fields;
1706         }
1707
1708         /**
1709          * Returns the error number of the last query
1710          *
1711          * @return string Error number (0 if no error)
1712          */
1713         public function errorNo()
1714         {
1715                 return $this->errorno;
1716         }
1717
1718         /**
1719          * Returns the error message of the last query
1720          *
1721          * @return string Error message ('' if no error)
1722          */
1723         public function errorMessage()
1724         {
1725                 return $this->error;
1726         }
1727
1728         /**
1729          * Closes the current statement
1730          *
1731          * @param object $stmt statement object
1732          *
1733          * @return boolean was the close successful?
1734          */
1735         public function close($stmt)
1736         {
1737
1738                 $stamp1 = microtime(true);
1739
1740                 if (!is_object($stmt)) {
1741                         return false;
1742                 }
1743
1744                 switch ($this->driver) {
1745                         case self::PDO:
1746                                 $ret = $stmt->closeCursor();
1747                                 break;
1748                         case self::MYSQLI:
1749                                 // MySQLi offers both a mysqli_stmt and a mysqli_result class.
1750                                 // We should be careful not to assume the object type of $stmt
1751                                 // because DBA::p() has been able to return both types.
1752                                 if ($stmt instanceof mysqli_stmt) {
1753                                         $stmt->free_result();
1754                                         $ret = $stmt->close();
1755                                 } elseif ($stmt instanceof mysqli_result) {
1756                                         $stmt->free();
1757                                         $ret = true;
1758                                 } else {
1759                                         $ret = false;
1760                                 }
1761                                 break;
1762                 }
1763
1764                 $this->profiler->saveTimestamp($stamp1, 'database');
1765
1766                 return $ret;
1767         }
1768
1769         /**
1770          * Return a list of database processes
1771          *
1772          * @return array
1773          *      'list' => List of processes, separated in their different states
1774          *      'amount' => Number of concurrent database processes
1775          * @throws \Exception
1776          */
1777         public function processlist()
1778         {
1779                 $ret  = $this->p("SHOW PROCESSLIST");
1780                 $data = $this->toArray($ret);
1781
1782                 $processes = 0;
1783                 $states    = [];
1784                 foreach ($data as $process) {
1785                         $state = trim($process["State"]);
1786
1787                         // Filter out all non blocking processes
1788                         if (!in_array($state, ["", "init", "statistics", "updating"])) {
1789                                 ++$states[$state];
1790                                 ++$processes;
1791                         }
1792                 }
1793
1794                 $statelist = "";
1795                 foreach ($states as $state => $usage) {
1796                         if ($statelist != "") {
1797                                 $statelist .= ", ";
1798                         }
1799                         $statelist .= $state . ": " . $usage;
1800                 }
1801                 return (["list" => $statelist, "amount" => $processes]);
1802         }
1803
1804         /**
1805          * Fetch a database variable
1806          *
1807          * @param string $name
1808          * @return string content
1809          */
1810         public function getVariable(string $name)
1811         {
1812                 $result = $this->fetchFirst("SHOW GLOBAL VARIABLES WHERE `Variable_name` = ?", $name);
1813                 return $result['Value'] ?? null;
1814         }
1815
1816         /**
1817          * Checks if $array is a filled array with at least one entry.
1818          *
1819          * @param mixed $array A filled array with at least one entry
1820          *
1821          * @return boolean Whether $array is a filled array or an object with rows
1822          */
1823         public function isResult($array)
1824         {
1825                 // It could be a return value from an update statement
1826                 if (is_bool($array)) {
1827                         return $array;
1828                 }
1829
1830                 if (is_object($array)) {
1831                         return $this->numRows($array) > 0;
1832                 }
1833
1834                 return (is_array($array) && (count($array) > 0));
1835         }
1836
1837         /**
1838          * Callback function for "esc_array"
1839          *
1840          * @param mixed   $value         Array value
1841          * @param string  $key           Array key
1842          * @param boolean $add_quotation add quotation marks for string values
1843          *
1844          * @return void
1845          */
1846         private function escapeArrayCallback(&$value, $key, $add_quotation)
1847         {
1848                 if (!$add_quotation) {
1849                         if (is_bool($value)) {
1850                                 $value = ($value ? '1' : '0');
1851                         } else {
1852                                 $value = $this->escape($value);
1853                         }
1854                         return;
1855                 }
1856
1857                 if (is_bool($value)) {
1858                         $value = ($value ? 'true' : 'false');
1859                 } elseif (is_float($value) || is_integer($value)) {
1860                         $value = (string)$value;
1861                 } else {
1862                         $value = "'" . $this->escape($value) . "'";
1863                 }
1864         }
1865
1866         /**
1867          * Escapes a whole array
1868          *
1869          * @param mixed   $arr           Array with values to be escaped
1870          * @param boolean $add_quotation add quotation marks for string values
1871          *
1872          * @return void
1873          */
1874         public function escapeArray(&$arr, $add_quotation = false)
1875         {
1876                 array_walk($arr, [$this, 'escapeArrayCallback'], $add_quotation);
1877         }
1878 }