src/Database/DBA.php

   1 <?php
   2
   3 namespace Friendica\Database;
   4
   5 // Do not use Core\Config in this class at risk of infinite loop.
   6 // Please use App->getConfigVariable() instead.
   7 //use Friendica\Core\Config;
   8
   9 use Friendica\Core\System;
  10 use Friendica\Util\DateTimeFormat;
  11 use mysqli;
  12 use mysqli_result;
  13 use mysqli_stmt;
  14 use PDO;
  15 use PDOException;
  16 use PDOStatement;
  17
  18 require_once 'include/dba.php';
  19
  20 /**
  21  * @class MySQL database class
  22  *
  23  * This class is for the low level database stuff that does driver specific things.
  24  */
  25 class DBA
  26 {
  27         const NULL_DATE     = '0001-01-01';
  28         const NULL_DATETIME = '0001-01-01 00:00:00';
  29
  30         public static $connected = false;
  31
  32         private static $server_info = '';
  33         private static $connection;
  34         private static $driver;
  35         private static $error = false;
  36         private static $errorno = 0;
  37         private static $affected_rows = 0;
  38         private static $in_transaction = false;
  39         private static $in_retrial = false;
  40         private static $relation = [];
  41         private static $db_serveraddr = '';
  42         private static $db_user = '';
  43         private static $db_pass = '';
  44         private static $db_name = '';
  45         private static $db_charset = '';
  46
  47         public static function connect($serveraddr, $user, $pass, $db, $charset = null)
  48         {
  49                 if (!is_null(self::$connection) && self::connected()) {
  50                         return true;
  51                 }
  52
  53                 // We are storing these values for being able to perform a reconnect
  54                 self::$db_serveraddr = $serveraddr;
  55                 self::$db_user = $user;
  56                 self::$db_pass = $pass;
  57                 self::$db_name = $db;
  58                 self::$db_charset = $charset;
  59
  60                 $port = 0;
  61                 $serveraddr = trim($serveraddr);
  62
  63                 $serverdata = explode(':', $serveraddr);
  64                 $server = $serverdata[0];
  65
  66                 if (count($serverdata) > 1) {
  67                         $port = trim($serverdata[1]);
  68                 }
  69
  70                 $server = trim($server);
  71                 $user = trim($user);
  72                 $pass = trim($pass);
  73                 $db = trim($db);
  74                 $charset = trim($charset);
  75
  76                 if (!(strlen($server) && strlen($user))) {
  77                         return false;
  78                 }
  79
  80                 if (class_exists('\PDO') && in_array('mysql', PDO::getAvailableDrivers())) {
  81                         self::$driver = 'pdo';
  82                         $connect = "mysql:host=".$server.";dbname=".$db;
  83
  84                         if ($port > 0) {
  85                                 $connect .= ";port=".$port;
  86                         }
  87
  88                         if ($charset) {
  89                                 $connect .= ";charset=".$charset;
  90                         }
  91
  92                         try {
  93                                 self::$connection = @new PDO($connect, $user, $pass);
  94                                 self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
  95                                 self::$connected = true;
  96                         } catch (PDOException $e) {
  97                                 /// @TODO At least log exception, don't ignore it!
  98                         }
  99                 }
 100
 101                 if (!self::$connected && class_exists('\mysqli')) {
 102                         self::$driver = 'mysqli';
 103
 104                         if ($port > 0) {
 105                                 self::$connection = @new mysqli($server, $user, $pass, $db, $port);
 106                         } else {
 107                                 self::$connection = @new mysqli($server, $user, $pass, $db);
 108                         }
 109
 110                         if (!mysqli_connect_errno()) {
 111                                 self::$connected = true;
 112
 113                                 if ($charset) {
 114                                         self::$connection->set_charset($charset);
 115                                 }
 116                         }
 117                 }
 118
 119                 // No suitable SQL driver was found.
 120                 if (!self::$connected) {
 121                         self::$driver = null;
 122                         self::$connection = null;
 123                 }
 124
 125                 return self::$connected;
 126         }
 127
 128         /**
 129          * Disconnects the current database connection
 130          */
 131         public static function disconnect()
 132         {
 133                 if (is_null(self::$connection)) {
 134                         return;
 135                 }
 136
 137                 switch (self::$driver) {
 138                         case 'pdo':
 139                                 self::$connection = null;
 140                                 break;
 141                         case 'mysqli':
 142                                 self::$connection->close();
 143                                 self::$connection = null;
 144                                 break;
 145                 }
 146         }
 147
 148         /**
 149          * Perform a reconnect of an existing database connection
 150          */
 151         public static function reconnect() {
 152                 self::disconnect();
 153
 154                 $ret = self::connect(self::$db_serveraddr, self::$db_user, self::$db_pass, self::$db_name, self::$db_charset);
 155                 return $ret;
 156         }
 157
 158         /**
 159          * Return the database object.
 160          * @return PDO|mysqli
 161          */
 162         public static function getConnection()
 163         {
 164                 return self::$connection;
 165         }
 166
 167         /**
 168          * @brief Returns the MySQL server version string
 169          *
 170          * This function discriminate between the deprecated mysql API and the current
 171          * object-oriented mysqli API. Example of returned string: 5.5.46-0+deb8u1
 172          *
 173          * @return string
 174          */
 175         public static function serverInfo() {
 176                 if (self::$server_info == '') {
 177                         switch (self::$driver) {
 178                                 case 'pdo':
 179                                         self::$server_info = self::$connection->getAttribute(PDO::ATTR_SERVER_VERSION);
 180                                         break;
 181                                 case 'mysqli':
 182                                         self::$server_info = self::$connection->server_info;
 183                                         break;
 184                         }
 185                 }
 186                 return self::$server_info;
 187         }
 188
 189         /**
 190          * @brief Returns the selected database name
 191          *
 192          * @return string
 193          */
 194         public static function databaseName() {
 195                 $ret = self::p("SELECT DATABASE() AS `db`");
 196                 $data = self::toArray($ret);
 197                 return $data[0]['db'];
 198         }
 199
 200         /**
 201          * @brief Analyze a database query and log this if some conditions are met.
 202          *
 203          * @param string $query The database query that will be analyzed
 204          */
 205         private static function logIndex($query) {
 206                 $a = get_app();
 207
 208                 if (!$a->getConfigVariable('system', 'db_log_index')) {
 209                         return;
 210                 }
 211
 212                 // Don't explain an explain statement
 213                 if (strtolower(substr($query, 0, 7)) == "explain") {
 214                         return;
 215                 }
 216
 217                 // Only do the explain on "select", "update" and "delete"
 218                 if (!in_array(strtolower(substr($query, 0, 6)), ["select", "update", "delete"])) {
 219                         return;
 220                 }
 221
 222                 $r = self::p("EXPLAIN ".$query);
 223                 if (!self::isResult($r)) {
 224                         return;
 225                 }
 226
 227                 $watchlist = explode(',', $a->getConfigVariable('system', 'db_log_index_watch'));
 228                 $blacklist = explode(',', $a->getConfigVariable('system', 'db_log_index_blacklist'));
 229
 230                 while ($row = self::fetch($r)) {
 231                         if ((intval($a->getConfigVariable('system', 'db_loglimit_index')) > 0)) {
 232                                 $log = (in_array($row['key'], $watchlist) &&
 233                                         ($row['rows'] >= intval($a->getConfigVariable('system', 'db_loglimit_index'))));
 234                         } else {
 235                                 $log = false;
 236                         }
 237
 238                         if ((intval($a->getConfigVariable('system', 'db_loglimit_index_high')) > 0) && ($row['rows'] >= intval($a->getConfigVariable('system', 'db_loglimit_index_high')))) {
 239                                 $log = true;
 240                         }
 241
 242                         if (in_array($row['key'], $blacklist) || ($row['key'] == "")) {
 243                                 $log = false;
 244                         }
 245
 246                         if ($log) {
 247                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 248                                 @file_put_contents($a->getConfigVariable('system', 'db_log_index'), DateTimeFormat::utcNow()."\t".
 249                                                 $row['key']."\t".$row['rows']."\t".$row['Extra']."\t".
 250                                                 basename($backtrace[1]["file"])."\t".
 251                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 252                                                 substr($query, 0, 2000)."\n", FILE_APPEND);
 253                         }
 254                 }
 255         }
 256
 257         public static function escape($str) {
 258                 if (self::$connected) {
 259                         switch (self::$driver) {
 260                                 case 'pdo':
 261                                         return substr(@self::$connection->quote($str, PDO::PARAM_STR), 1, -1);
 262
 263                                 case 'mysqli':
 264                                         return @self::$connection->real_escape_string($str);
 265                         }
 266                 } else {
 267                         return str_replace("'", "\\'", $str);
 268                 }
 269         }
 270
 271         public static function connected() {
 272                 $connected = false;
 273
 274                 if (is_null(self::$connection)) {
 275                         return false;
 276                 }
 277
 278                 switch (self::$driver) {
 279                         case 'pdo':
 280                                 $r = self::p("SELECT 1");
 281                                 if (self::isResult($r)) {
 282                                         $row = self::toArray($r);
 283                                         $connected = ($row[0]['1'] == '1');
 284                                 }
 285                                 break;
 286                         case 'mysqli':
 287                                 $connected = self::$connection->ping();
 288                                 break;
 289                 }
 290                 return $connected;
 291         }
 292
 293         /**
 294          * @brief Replaces ANY_VALUE() function by MIN() function,
 295          *  if the database server does not support ANY_VALUE().
 296          *
 297          * Considerations for Standard SQL, or MySQL with ONLY_FULL_GROUP_BY (default since 5.7.5).
 298          * ANY_VALUE() is available from MySQL 5.7.5 https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html
 299          * A standard fall-back is to use MIN().
 300          *
 301          * @param string $sql An SQL string without the values
 302          * @return string The input SQL string modified if necessary.
 303          */
 304         public static function anyValueFallback($sql) {
 305                 $server_info = self::serverInfo();
 306                 if (version_compare($server_info, '5.7.5', '<') ||
 307                         (stripos($server_info, 'MariaDB') !== false)) {
 308                         $sql = str_ireplace('ANY_VALUE(', 'MIN(', $sql);
 309                 }
 310                 return $sql;
 311         }
 312
 313         /**
 314          * @brief beautifies the query - useful for "SHOW PROCESSLIST"
 315          *
 316          * This is safe when we bind the parameters later.
 317          * The parameter values aren't part of the SQL.
 318          *
 319          * @param string $sql An SQL string without the values
 320          * @return string The input SQL string modified if necessary.
 321          */
 322         public static function cleanQuery($sql) {
 323                 $search = ["\t", "\n", "\r", "  "];
 324                 $replace = [' ', ' ', ' ', ' '];
 325                 do {
 326                         $oldsql = $sql;
 327                         $sql = str_replace($search, $replace, $sql);
 328                 } while ($oldsql != $sql);
 329
 330                 return $sql;
 331         }
 332
 333
 334         /**
 335          * @brief Replaces the ? placeholders with the parameters in the $args array
 336          *
 337          * @param string $sql SQL query
 338          * @param array $args The parameters that are to replace the ? placeholders
 339          * @return string The replaced SQL query
 340          */
 341         private static function replaceParameters($sql, $args) {
 342                 $offset = 0;
 343                 foreach ($args AS $param => $value) {
 344                         if (is_int($args[$param]) || is_float($args[$param])) {
 345                                 $replace = intval($args[$param]);
 346                         } else {
 347                                 $replace = "'".self::escape($args[$param])."'";
 348                         }
 349
 350                         $pos = strpos($sql, '?', $offset);
 351                         if ($pos !== false) {
 352                                 $sql = substr_replace($sql, $replace, $pos, 1);
 353                         }
 354                         $offset = $pos + strlen($replace);
 355                 }
 356                 return $sql;
 357         }
 358
 359         /**
 360          * @brief Convert parameter array to an universal form
 361          * @param array $args Parameter array
 362          * @return array universalized parameter array
 363          */
 364         private static function getParam($args) {
 365                 unset($args[0]);
 366
 367                 // When the second function parameter is an array then use this as the parameter array
 368                 if ((count($args) > 0) && (is_array($args[1]))) {
 369                         return $args[1];
 370                 } else {
 371                         return $args;
 372                 }
 373         }
 374
 375         /**
 376          * @brief Executes a prepared statement that returns data
 377          * @usage Example: $r = p("SELECT * FROM `item` WHERE `guid` = ?", $guid);
 378          *
 379          * Please only use it with complicated queries.
 380          * For all regular queries please use DBA::select or DBA::exists
 381          *
 382          * @param string $sql SQL statement
 383          * @return bool|object statement object or result object
 384          */
 385         public static function p($sql) {
 386                 $a = get_app();
 387
 388                 $stamp1 = microtime(true);
 389
 390                 $params = self::getParam(func_get_args());
 391
 392                 // Renumber the array keys to be sure that they fit
 393                 $i = 0;
 394                 $args = [];
 395                 foreach ($params AS $param) {
 396                         // Avoid problems with some MySQL servers and boolean values. See issue #3645
 397                         if (is_bool($param)) {
 398                                 $param = (int)$param;
 399                         }
 400                         $args[++$i] = $param;
 401                 }
 402
 403                 if (!self::$connected) {
 404                         return false;
 405                 }
 406
 407                 if ((substr_count($sql, '?') != count($args)) && (count($args) > 0)) {
 408                         // Question: Should we continue or stop the query here?
 409                         logger('Parameter mismatch. Query "'.$sql.'" - Parameters '.print_r($args, true), LOGGER_DEBUG);
 410                 }
 411
 412                 $sql = self::cleanQuery($sql);
 413                 $sql = self::anyValueFallback($sql);
 414
 415                 $orig_sql = $sql;
 416
 417                 if ($a->getConfigValue('system', 'db_callstack')) {
 418                         $sql = "/*".System::callstack()." */ ".$sql;
 419                 }
 420
 421                 self::$error = '';
 422                 self::$errorno = 0;
 423                 self::$affected_rows = 0;
 424
 425                 // We have to make some things different if this function is called from "e"
 426                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
 427
 428                 if (isset($trace[1])) {
 429                         $called_from = $trace[1];
 430                 } else {
 431                         // We use just something that is defined to avoid warnings
 432                         $called_from = $trace[0];
 433                 }
 434                 // We are having an own error logging in the function "e"
 435                 $called_from_e = ($called_from['function'] == 'e');
 436
 437                 switch (self::$driver) {
 438                         case 'pdo':
 439                                 // If there are no arguments we use "query"
 440                                 if (count($args) == 0) {
 441                                         if (!$retval = self::$connection->query($sql)) {
 442                                                 $errorInfo = self::$connection->errorInfo();
 443                                                 self::$error = $errorInfo[2];
 444                                                 self::$errorno = $errorInfo[1];
 445                                                 $retval = false;
 446                                                 break;
 447                                         }
 448                                         self::$affected_rows = $retval->rowCount();
 449                                         break;
 450                                 }
 451
 452                                 if (!$stmt = self::$connection->prepare($sql)) {
 453                                         $errorInfo = self::$connection->errorInfo();
 454                                         self::$error = $errorInfo[2];
 455                                         self::$errorno = $errorInfo[1];
 456                                         $retval = false;
 457                                         break;
 458                                 }
 459
 460                                 foreach ($args AS $param => $value) {
 461                                         if (is_int($args[$param])) {
 462                                                 $data_type = PDO::PARAM_INT;
 463                                         } else {
 464                                                 $data_type = PDO::PARAM_STR;
 465                                         }
 466                                         $stmt->bindParam($param, $args[$param], $data_type);
 467                                 }
 468
 469                                 if (!$stmt->execute()) {
 470                                         $errorInfo = $stmt->errorInfo();
 471                                         self::$error = $errorInfo[2];
 472                                         self::$errorno = $errorInfo[1];
 473                                         $retval = false;
 474                                 } else {
 475                                         $retval = $stmt;
 476                                         self::$affected_rows = $retval->rowCount();
 477                                 }
 478                                 break;
 479                         case 'mysqli':
 480                                 // There are SQL statements that cannot be executed with a prepared statement
 481                                 $parts = explode(' ', $orig_sql);
 482                                 $command = strtolower($parts[0]);
 483                                 $can_be_prepared = in_array($command, ['select', 'update', 'insert', 'delete']);
 484
 485                                 // The fallback routine is called as well when there are no arguments
 486                                 if (!$can_be_prepared || (count($args) == 0)) {
 487                                         $retval = self::$connection->query(self::replaceParameters($sql, $args));
 488                                         if (self::$connection->errno) {
 489                                                 self::$error = self::$connection->error;
 490                                                 self::$errorno = self::$connection->errno;
 491                                                 $retval = false;
 492                                         } else {
 493                                                 if (isset($retval->num_rows)) {
 494                                                         self::$affected_rows = $retval->num_rows;
 495                                                 } else {
 496                                                         self::$affected_rows = self::$connection->affected_rows;
 497                                                 }
 498                                         }
 499                                         break;
 500                                 }
 501
 502                                 $stmt = self::$connection->stmt_init();
 503
 504                                 if (!$stmt->prepare($sql)) {
 505                                         self::$error = $stmt->error;
 506                                         self::$errorno = $stmt->errno;
 507                                         $retval = false;
 508                                         break;
 509                                 }
 510
 511                                 $param_types = '';
 512                                 $values = [];
 513                                 foreach ($args AS $param => $value) {
 514                                         if (is_int($args[$param])) {
 515                                                 $param_types .= 'i';
 516                                         } elseif (is_float($args[$param])) {
 517                                                 $param_types .= 'd';
 518                                         } elseif (is_string($args[$param])) {
 519                                                 $param_types .= 's';
 520                                         } else {
 521                                                 $param_types .= 'b';
 522                                         }
 523                                         $values[] = &$args[$param];
 524                                 }
 525
 526                                 if (count($values) > 0) {
 527                                         array_unshift($values, $param_types);
 528                                         call_user_func_array([$stmt, 'bind_param'], $values);
 529                                 }
 530
 531                                 if (!$stmt->execute()) {
 532                                         self::$error = self::$connection->error;
 533                                         self::$errorno = self::$connection->errno;
 534                                         $retval = false;
 535                                 } else {
 536                                         $stmt->store_result();
 537                                         $retval = $stmt;
 538                                         self::$affected_rows = $retval->affected_rows;
 539                                 }
 540                                 break;
 541                 }
 542
 543                 // We are having an own error logging in the function "e"
 544                 if ((self::$errorno != 0) && !$called_from_e) {
 545                         // We have to preserve the error code, somewhere in the logging it get lost
 546                         $error = self::$error;
 547                         $errorno = self::$errorno;
 548
 549                         logger('DB Error '.self::$errorno.': '.self::$error."\n".
 550                                 System::callstack(8)."\n".self::replaceParameters($sql, $args));
 551
 552                         // On a lost connection we try to reconnect - but only once.
 553                         if ($errorno == 2006) {
 554                                 if (self::$in_retrial || !self::reconnect()) {
 555                                         // It doesn't make sense to continue when the database connection was lost
 556                                         if (self::$in_retrial) {
 557                                                 logger('Giving up retrial because of database error '.$errorno.': '.$error);
 558                                         } else {
 559                                                 logger("Couldn't reconnect after database error ".$errorno.': '.$error);
 560                                         }
 561                                         exit(1);
 562                                 } else {
 563                                         // We try it again
 564                                         logger('Reconnected after database error '.$errorno.': '.$error);
 565                                         self::$in_retrial = true;
 566                                         $ret = self::p($sql, $args);
 567                                         self::$in_retrial = false;
 568                                         return $ret;
 569                                 }
 570                         }
 571
 572                         self::$error = $error;
 573                         self::$errorno = $errorno;
 574                 }
 575
 576                 $a->saveTimestamp($stamp1, 'database');
 577
 578                 if ($a->getConfigValue('system', 'db_log')) {
 579                         $stamp2 = microtime(true);
 580                         $duration = (float)($stamp2 - $stamp1);
 581
 582                         if (($duration > $a->getConfigValue('system', 'db_loglimit'))) {
 583                                 $duration = round($duration, 3);
 584                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 585
 586                                 @file_put_contents($a->getConfigValue('system', 'db_log'), DateTimeFormat::utcNow()."\t".$duration."\t".
 587                                                 basename($backtrace[1]["file"])."\t".
 588                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 589                                                 substr(self::replaceParameters($sql, $args), 0, 2000)."\n", FILE_APPEND);
 590                         }
 591                 }
 592                 return $retval;
 593         }
 594
 595         /**
 596          * @brief Executes a prepared statement like UPDATE or INSERT that doesn't return data
 597          *
 598          * Please use DBA::delete, DBA::insert, DBA::update, ... instead
 599          *
 600          * @param string $sql SQL statement
 601          * @return boolean Was the query successfull? False is returned only if an error occurred
 602          */
 603         public static function e($sql) {
 604                 $a = get_app();
 605
 606                 $stamp = microtime(true);
 607
 608                 $params = self::getParam(func_get_args());
 609
 610                 // In a case of a deadlock we are repeating the query 20 times
 611                 $timeout = 20;
 612
 613                 do {
 614                         $stmt = self::p($sql, $params);
 615
 616                         if (is_bool($stmt)) {
 617                                 $retval = $stmt;
 618                         } elseif (is_object($stmt)) {
 619                                 $retval = true;
 620                         } else {
 621                                 $retval = false;
 622                         }
 623
 624                         self::close($stmt);
 625
 626                 } while ((self::$errorno == 1213) && (--$timeout > 0));
 627
 628                 if (self::$errorno != 0) {
 629                         // We have to preserve the error code, somewhere in the logging it get lost
 630                         $error = self::$error;
 631                         $errorno = self::$errorno;
 632
 633                         logger('DB Error '.self::$errorno.': '.self::$error."\n".
 634                                 System::callstack(8)."\n".self::replaceParameters($sql, $params));
 635
 636                         // On a lost connection we simply quit.
 637                         // A reconnect like in self::p could be dangerous with modifications
 638                         if ($errorno == 2006) {
 639                                 logger('Giving up because of database error '.$errorno.': '.$error);
 640                                 exit(1);
 641                         }
 642
 643                         self::$error = $error;
 644                         self::$errorno = $errorno;
 645                 }
 646
 647                 $a->saveTimestamp($stamp, "database_write");
 648
 649                 return $retval;
 650         }
 651
 652         /**
 653          * @brief Check if data exists
 654          *
 655          * @param string $table Table name
 656          * @param array $condition array of fields for condition
 657          *
 658          * @return boolean Are there rows for that condition?
 659          */
 660         public static function exists($table, $condition) {
 661                 if (empty($table)) {
 662                         return false;
 663                 }
 664
 665                 $fields = [];
 666
 667                 if (empty($condition)) {
 668                         return DBStructure::existsTable($table);
 669                 }
 670
 671                 reset($condition);
 672                 $first_key = key($condition);
 673                 if (!is_int($first_key)) {
 674                         $fields = [$first_key];
 675                 }
 676
 677                 $stmt = self::select($table, $fields, $condition, ['limit' => 1]);
 678
 679                 if (is_bool($stmt)) {
 680                         $retval = $stmt;
 681                 } else {
 682                         $retval = (self::numRows($stmt) > 0);
 683                 }
 684
 685                 self::close($stmt);
 686
 687                 return $retval;
 688         }
 689
 690         /**
 691          * Fetches the first row
 692          *
 693          * Please use DBA::selectFirst or DBA::exists whenever this is possible.
 694          *
 695          * @brief Fetches the first row
 696          * @param string $sql SQL statement
 697          * @return array first row of query
 698          */
 699         public static function fetchFirst($sql) {
 700                 $params = self::getParam(func_get_args());
 701
 702                 $stmt = self::p($sql, $params);
 703
 704                 if (is_bool($stmt)) {
 705                         $retval = $stmt;
 706                 } else {
 707                         $retval = self::fetch($stmt);
 708                 }
 709
 710                 self::close($stmt);
 711
 712                 return $retval;
 713         }
 714
 715         /**
 716          * @brief Returns the number of affected rows of the last statement
 717          *
 718          * @return int Number of rows
 719          */
 720         public static function affectedRows() {
 721                 return self::$affected_rows;
 722         }
 723
 724         /**
 725          * @brief Returns the number of columns of a statement
 726          *
 727          * @param object Statement object
 728          * @return int Number of columns
 729          */
 730         public static function columnCount($stmt) {
 731                 if (!is_object($stmt)) {
 732                         return 0;
 733                 }
 734                 switch (self::$driver) {
 735                         case 'pdo':
 736                                 return $stmt->columnCount();
 737                         case 'mysqli':
 738                                 return $stmt->field_count;
 739                 }
 740                 return 0;
 741         }
 742         /**
 743          * @brief Returns the number of rows of a statement
 744          *
 745          * @param PDOStatement|mysqli_result|mysqli_stmt Statement object
 746          * @return int Number of rows
 747          */
 748         public static function numRows($stmt) {
 749                 if (!is_object($stmt)) {
 750                         return 0;
 751                 }
 752                 switch (self::$driver) {
 753                         case 'pdo':
 754                                 return $stmt->rowCount();
 755                         case 'mysqli':
 756                                 return $stmt->num_rows;
 757                 }
 758                 return 0;
 759         }
 760
 761         /**
 762          * @brief Fetch a single row
 763          *
 764          * @param mixed $stmt statement object
 765          * @return array current row
 766          */
 767         public static function fetch($stmt) {
 768                 $a = get_app();
 769
 770                 $stamp1 = microtime(true);
 771
 772                 $columns = [];
 773
 774                 if (!is_object($stmt)) {
 775                         return false;
 776                 }
 777
 778                 switch (self::$driver) {
 779                         case 'pdo':
 780                                 $columns = $stmt->fetch(PDO::FETCH_ASSOC);
 781                                 break;
 782                         case 'mysqli':
 783                                 if (get_class($stmt) == 'mysqli_result') {
 784                                         $columns = $stmt->fetch_assoc();
 785                                         break;
 786                                 }
 787
 788                                 // This code works, but is slow
 789
 790                                 // Bind the result to a result array
 791                                 $cols = [];
 792
 793                                 $cols_num = [];
 794                                 for ($x = 0; $x < $stmt->field_count; $x++) {
 795                                         $cols[] = &$cols_num[$x];
 796                                 }
 797
 798                                 call_user_func_array([$stmt, 'bind_result'], $cols);
 799
 800                                 if (!$stmt->fetch()) {
 801                                         return false;
 802                                 }
 803
 804                                 // The slow part:
 805                                 // We need to get the field names for the array keys
 806                                 // It seems that there is no better way to do this.
 807                                 $result = $stmt->result_metadata();
 808                                 $fields = $result->fetch_fields();
 809
 810                                 foreach ($cols_num AS $param => $col) {
 811                                         $columns[$fields[$param]->name] = $col;
 812                                 }
 813                 }
 814
 815                 $a->saveTimestamp($stamp1, 'database');
 816
 817                 return $columns;
 818         }
 819
 820         /**
 821          * @brief Insert a row into a table
 822          *
 823          * @param string $table Table name
 824          * @param array $param parameter array
 825          * @param bool $on_duplicate_update Do an update on a duplicate entry
 826          *
 827          * @return boolean was the insert successful?
 828          */
 829         public static function insert($table, $param, $on_duplicate_update = false) {
 830
 831                 if (empty($table) || empty($param)) {
 832                         logger('Table and fields have to be set');
 833                         return false;
 834                 }
 835
 836                 $sql = "INSERT INTO `".self::escape($table)."` (`".implode("`, `", array_keys($param))."`) VALUES (".
 837                         substr(str_repeat("?, ", count($param)), 0, -2).")";
 838
 839                 if ($on_duplicate_update) {
 840                         $sql .= " ON DUPLICATE KEY UPDATE `".implode("` = ?, `", array_keys($param))."` = ?";
 841
 842                         $values = array_values($param);
 843                         $param = array_merge_recursive($values, $values);
 844                 }
 845
 846                 return self::e($sql, $param);
 847         }
 848
 849         /**
 850          * @brief Fetch the id of the last insert command
 851          *
 852          * @return integer Last inserted id
 853          */
 854         public static function lastInsertId() {
 855                 switch (self::$driver) {
 856                         case 'pdo':
 857                                 $id = self::$connection->lastInsertId();
 858                                 break;
 859                         case 'mysqli':
 860                                 $id = self::$connection->insert_id;
 861                                 break;
 862                 }
 863                 return $id;
 864         }
 865
 866         /**
 867          * @brief Locks a table for exclusive write access
 868          *
 869          * This function can be extended in the future to accept a table array as well.
 870          *
 871          * @param string $table Table name
 872          *
 873          * @return boolean was the lock successful?
 874          */
 875         public static function lock($table) {
 876                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
 877                 if (self::$driver == 'pdo') {
 878                         self::e("SET autocommit=0");
 879                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
 880                 } else {
 881                         self::$connection->autocommit(false);
 882                 }
 883
 884                 $success = self::e("LOCK TABLES `".self::escape($table)."` WRITE");
 885
 886                 if (self::$driver == 'pdo') {
 887                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
 888                 }
 889
 890                 if (!$success) {
 891                         if (self::$driver == 'pdo') {
 892                                 self::e("SET autocommit=1");
 893                         } else {
 894                                 self::$connection->autocommit(true);
 895                         }
 896                 } else {
 897                         self::$in_transaction = true;
 898                 }
 899                 return $success;
 900         }
 901
 902         /**
 903          * @brief Unlocks all locked tables
 904          *
 905          * @return boolean was the unlock successful?
 906          */
 907         public static function unlock() {
 908                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
 909                 self::performCommit();
 910
 911                 if (self::$driver == 'pdo') {
 912                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
 913                 }
 914
 915                 $success = self::e("UNLOCK TABLES");
 916
 917                 if (self::$driver == 'pdo') {
 918                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
 919                         self::e("SET autocommit=1");
 920                 } else {
 921                         self::$connection->autocommit(true);
 922                 }
 923
 924                 self::$in_transaction = false;
 925                 return $success;
 926         }
 927
 928         /**
 929          * @brief Starts a transaction
 930          *
 931          * @return boolean Was the command executed successfully?
 932          */
 933         public static function transaction() {
 934                 if (!self::performCommit()) {
 935                         return false;
 936                 }
 937
 938                 switch (self::$driver) {
 939                         case 'pdo':
 940                                 if (!self::$connection->inTransaction() && !self::$connection->beginTransaction()) {
 941                                         return false;
 942                                 }
 943                                 break;
 944
 945                         case 'mysqli':
 946                                 if (!self::$connection->begin_transaction()) {
 947                                         return false;
 948                                 }
 949                                 break;
 950                 }
 951
 952                 self::$in_transaction = true;
 953                 return true;
 954         }
 955
 956         private static function performCommit()
 957         {
 958                 switch (self::$driver) {
 959                         case 'pdo':
 960                                 if (!self::$connection->inTransaction()) {
 961                                         return true;
 962                                 }
 963
 964                                 return self::$connection->commit();
 965
 966                         case 'mysqli':
 967                                 return self::$connection->commit();
 968                 }
 969
 970                 return true;
 971         }
 972
 973         /**
 974          * @brief Does a commit
 975          *
 976          * @return boolean Was the command executed successfully?
 977          */
 978         public static function commit() {
 979                 if (!self::performCommit()) {
 980                         return false;
 981                 }
 982                 self::$in_transaction = false;
 983                 return true;
 984         }
 985
 986         /**
 987          * @brief Does a rollback
 988          *
 989          * @return boolean Was the command executed successfully?
 990          */
 991         public static function rollback() {
 992                 $ret = false;
 993
 994                 switch (self::$driver) {
 995                         case 'pdo':
 996                                 if (!self::$connection->inTransaction()) {
 997                                         $ret = true;
 998                                         break;
 999                                 }
1000                                 $ret = self::$connection->rollBack();
1001                                 break;
1002
1003                         case 'mysqli':
1004                                 $ret = self::$connection->rollback();
1005                                 break;
1006                 }
1007                 self::$in_transaction = false;
1008                 return $ret;
1009         }
1010
1011         /**
1012          * @brief Build the array with the table relations
1013          *
1014          * The array is build from the database definitions in DBStructure.php
1015          *
1016          * This process must only be started once, since the value is cached.
1017          */
1018         private static function buildRelationData() {
1019                 $definition = DBStructure::definition();
1020
1021                 foreach ($definition AS $table => $structure) {
1022                         foreach ($structure['fields'] AS $field => $field_struct) {
1023                                 if (isset($field_struct['relation'])) {
1024                                         foreach ($field_struct['relation'] AS $rel_table => $rel_field) {
1025                                                 self::$relation[$rel_table][$rel_field][$table][] = $field;
1026                                         }
1027                                 }
1028                         }
1029                 }
1030         }
1031
1032         /**
1033          * @brief Delete a row from a table
1034          *
1035          * @param string  $table       Table name
1036          * @param array   $conditions  Field condition(s)
1037          * @param array   $options
1038          *                - cascade: If true we delete records in other tables that depend on the one we're deleting through
1039          *                           relations (default: true)
1040          * @param boolean $in_process  Internal use: Only do a commit after the last delete
1041          * @param array   $callstack   Internal use: prevent endless loops
1042          *
1043          * @return boolean|array was the delete successful? When $in_process is set: deletion data
1044          */
1045         public static function delete($table, array $conditions, array $options = [], $in_process = false, array &$callstack = [])
1046         {
1047                 if (empty($table) || empty($conditions)) {
1048                         logger('Table and conditions have to be set');
1049                         return false;
1050                 }
1051
1052                 $commands = [];
1053
1054                 // Create a key for the loop prevention
1055                 $key = $table . ':' . json_encode($conditions);
1056
1057                 // We quit when this key already exists in the callstack.
1058                 if (isset($callstack[$key])) {
1059                         return $commands;
1060                 }
1061
1062                 $callstack[$key] = true;
1063
1064                 $table = self::escape($table);
1065
1066                 $commands[$key] = ['table' => $table, 'conditions' => $conditions];
1067
1068                 // Don't use "defaults" here, since it would set "false" to "true"
1069                 if (isset($options['cascade'])) {
1070                         $cascade = $options['cascade'];
1071                 } else {
1072                         $cascade = true;
1073                 }
1074
1075                 // To speed up the whole process we cache the table relations
1076                 if ($cascade && count(self::$relation) == 0) {
1077                         self::buildRelationData();
1078                 }
1079
1080                 // Is there a relation entry for the table?
1081                 if ($cascade && isset(self::$relation[$table])) {
1082                         // We only allow a simple "one field" relation.
1083                         $field = array_keys(self::$relation[$table])[0];
1084                         $rel_def = array_values(self::$relation[$table])[0];
1085
1086                         // Create a key for preventing double queries
1087                         $qkey = $field . '-' . $table . ':' . json_encode($conditions);
1088
1089                         // When the search field is the relation field, we don't need to fetch the rows
1090                         // This is useful when the leading record is already deleted in the frontend but the rest is done in the backend
1091                         if ((count($conditions) == 1) && ($field == array_keys($conditions)[0])) {
1092                                 foreach ($rel_def AS $rel_table => $rel_fields) {
1093                                         foreach ($rel_fields AS $rel_field) {
1094                                                 $retval = self::delete($rel_table, [$rel_field => array_values($conditions)[0]], $options, true, $callstack);
1095                                                 $commands = array_merge($commands, $retval);
1096                                         }
1097                                 }
1098                                 // We quit when this key already exists in the callstack.
1099                         } elseif (!isset($callstack[$qkey])) {
1100
1101                                 $callstack[$qkey] = true;
1102
1103                                 // Fetch all rows that are to be deleted
1104                                 $data = self::select($table, [$field], $conditions);
1105
1106                                 while ($row = self::fetch($data)) {
1107                                         // Now we accumulate the delete commands
1108                                         $retval = self::delete($table, [$field => $row[$field]], $options, true, $callstack);
1109                                         $commands = array_merge($commands, $retval);
1110                                 }
1111
1112                                 self::close($data);
1113
1114                                 // Since we had split the delete command we don't need the original command anymore
1115                                 unset($commands[$key]);
1116                         }
1117                 }
1118
1119                 if (!$in_process) {
1120                         // Now we finalize the process
1121                         $do_transaction = !self::$in_transaction;
1122
1123                         if ($do_transaction) {
1124                                 self::transaction();
1125                         }
1126
1127                         $compacted = [];
1128                         $counter = [];
1129
1130                         foreach ($commands AS $command) {
1131                                 $conditions = $command['conditions'];
1132                                 reset($conditions);
1133                                 $first_key = key($conditions);
1134
1135                                 $condition_string = self::buildCondition($conditions);
1136
1137                                 if ((count($command['conditions']) > 1) || is_int($first_key)) {
1138                                         $sql = "DELETE FROM `" . $command['table'] . "`" . $condition_string;
1139                                         logger(self::replaceParameters($sql, $conditions), LOGGER_DATA);
1140
1141                                         if (!self::e($sql, $conditions)) {
1142                                                 if ($do_transaction) {
1143                                                         self::rollback();
1144                                                 }
1145                                                 return false;
1146                                         }
1147                                 } else {
1148                                         $key_table = $command['table'];
1149                                         $key_condition = array_keys($command['conditions'])[0];
1150                                         $value = array_values($command['conditions'])[0];
1151
1152                                         // Split the SQL queries in chunks of 100 values
1153                                         // We do the $i stuff here to make the code better readable
1154                                         $i = isset($counter[$key_table][$key_condition]) ? $counter[$key_table][$key_condition] : 0;
1155                                         if (isset($compacted[$key_table][$key_condition][$i]) && count($compacted[$key_table][$key_condition][$i]) > 100) {
1156                                                 ++$i;
1157                                         }
1158
1159                                         $compacted[$key_table][$key_condition][$i][$value] = $value;
1160                                         $counter[$key_table][$key_condition] = $i;
1161                                 }
1162                         }
1163                         foreach ($compacted AS $table => $values) {
1164                                 foreach ($values AS $field => $field_value_list) {
1165                                         foreach ($field_value_list AS $field_values) {
1166                                                 $sql = "DELETE FROM `" . $table . "` WHERE `" . $field . "` IN (" .
1167                                                         substr(str_repeat("?, ", count($field_values)), 0, -2) . ");";
1168
1169                                                 logger(self::replaceParameters($sql, $field_values), LOGGER_DATA);
1170
1171                                                 if (!self::e($sql, $field_values)) {
1172                                                         if ($do_transaction) {
1173                                                                 self::rollback();
1174                                                         }
1175                                                         return false;
1176                                                 }
1177                                         }
1178                                 }
1179                         }
1180                         if ($do_transaction) {
1181                                 self::commit();
1182                         }
1183                         return true;
1184                 }
1185
1186                 return $commands;
1187         }
1188
1189         /**
1190          * @brief Updates rows
1191          *
1192          * Updates rows in the database. When $old_fields is set to an array,
1193          * the system will only do an update if the fields in that array changed.
1194          *
1195          * Attention:
1196          * Only the values in $old_fields are compared.
1197          * This is an intentional behaviour.
1198          *
1199          * Example:
1200          * We include the timestamp field in $fields but not in $old_fields.
1201          * Then the row will only get the new timestamp when the other fields had changed.
1202          *
1203          * When $old_fields is set to a boolean value the system will do this compare itself.
1204          * When $old_fields is set to "true" the system will do an insert if the row doesn't exists.
1205          *
1206          * Attention:
1207          * Only set $old_fields to a boolean value when you are sure that you will update a single row.
1208          * When you set $old_fields to "true" then $fields must contain all relevant fields!
1209          *
1210          * @param string $table Table name
1211          * @param array $fields contains the fields that are updated
1212          * @param array $condition condition array with the key values
1213          * @param array|boolean $old_fields array with the old field values that are about to be replaced (true = update on duplicate)
1214          *
1215          * @return boolean was the update successfull?
1216          */
1217         public static function update($table, $fields, $condition, $old_fields = []) {
1218
1219                 if (empty($table) || empty($fields) || empty($condition)) {
1220                         logger('Table, fields and condition have to be set');
1221                         return false;
1222                 }
1223
1224                 $table = self::escape($table);
1225
1226                 $condition_string = self::buildCondition($condition);
1227
1228                 if (is_bool($old_fields)) {
1229                         $do_insert = $old_fields;
1230
1231                         $old_fields = self::selectFirst($table, [], $condition);
1232
1233                         if (is_bool($old_fields)) {
1234                                 if ($do_insert) {
1235                                         $values = array_merge($condition, $fields);
1236                                         return self::insert($table, $values, $do_insert);
1237                                 }
1238                                 $old_fields = [];
1239                         }
1240                 }
1241
1242                 $do_update = (count($old_fields) == 0);
1243
1244                 foreach ($old_fields AS $fieldname => $content) {
1245                         if (isset($fields[$fieldname])) {
1246                                 if ($fields[$fieldname] == $content) {
1247                                         unset($fields[$fieldname]);
1248                                 } else {
1249                                         $do_update = true;
1250                                 }
1251                         }
1252                 }
1253
1254                 if (!$do_update || (count($fields) == 0)) {
1255                         return true;
1256                 }
1257
1258                 $sql = "UPDATE `".$table."` SET `".
1259                         implode("` = ?, `", array_keys($fields))."` = ?".$condition_string;
1260
1261                 $params1 = array_values($fields);
1262                 $params2 = array_values($condition);
1263                 $params = array_merge_recursive($params1, $params2);
1264
1265                 return self::e($sql, $params);
1266         }
1267
1268         /**
1269          * Retrieve a single record from a table and returns it in an associative array
1270          *
1271          * @brief Retrieve a single record from a table
1272          * @param string $table
1273          * @param array  $fields
1274          * @param array  $condition
1275          * @param array  $params
1276          * @return bool|array
1277          * @see self::select
1278          */
1279         public static function selectFirst($table, array $fields = [], array $condition = [], $params = [])
1280         {
1281                 $params['limit'] = 1;
1282                 $result = self::select($table, $fields, $condition, $params);
1283
1284                 if (is_bool($result)) {
1285                         return $result;
1286                 } else {
1287                         $row = self::fetch($result);
1288                         self::close($result);
1289                         return $row;
1290                 }
1291         }
1292
1293         /**
1294          * @brief Select rows from a table
1295          *
1296          * @param string $table     Table name
1297          * @param array  $fields    Array of selected fields, empty for all
1298          * @param array  $condition Array of fields for condition
1299          * @param array  $params    Array of several parameters
1300          *
1301          * @return boolean|object
1302          *
1303          * Example:
1304          * $table = "item";
1305          * $fields = array("id", "uri", "uid", "network");
1306          *
1307          * $condition = array("uid" => 1, "network" => 'dspr');
1308          * or:
1309          * $condition = array("`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr');
1310          *
1311          * $params = array("order" => array("id", "received" => true), "limit" => 10);
1312          *
1313          * $data = DBA::select($table, $fields, $condition, $params);
1314          */
1315         public static function select($table, array $fields = [], array $condition = [], array $params = [])
1316         {
1317                 if ($table == '') {
1318                         return false;
1319                 }
1320
1321                 $table = self::escape($table);
1322
1323                 if (count($fields) > 0) {
1324                         $select_fields = "`" . implode("`, `", array_values($fields)) . "`";
1325                 } else {
1326                         $select_fields = "*";
1327                 }
1328
1329                 $condition_string = self::buildCondition($condition);
1330
1331                 $param_string = self::buildParameter($params);
1332
1333                 $sql = "SELECT " . $select_fields . " FROM `" . $table . "`" . $condition_string . $param_string;
1334
1335                 $result = self::p($sql, $condition);
1336
1337                 return $result;
1338         }
1339
1340         /**
1341          * @brief Counts the rows from a table satisfying the provided condition
1342          *
1343          * @param string $table Table name
1344          * @param array $condition array of fields for condition
1345          *
1346          * @return int
1347          *
1348          * Example:
1349          * $table = "item";
1350          *
1351          * $condition = ["uid" => 1, "network" => 'dspr'];
1352          * or:
1353          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1354          *
1355          * $count = DBA::count($table, $condition);
1356          */
1357         public static function count($table, array $condition = [])
1358         {
1359                 if ($table == '') {
1360                         return false;
1361                 }
1362
1363                 $condition_string = self::buildCondition($condition);
1364
1365                 $sql = "SELECT COUNT(*) AS `count` FROM `".$table."`".$condition_string;
1366
1367                 $row = self::fetchFirst($sql, $condition);
1368
1369                 return $row['count'];
1370         }
1371
1372         /**
1373          * @brief Returns the SQL condition string built from the provided condition array
1374          *
1375          * This function operates with two modes.
1376          * - Supplied with a filed/value associative array, it builds simple strict
1377          *   equality conditions linked by AND.
1378          * - Supplied with a flat list, the first element is the condition string and
1379          *   the following arguments are the values to be interpolated
1380          *
1381          * $condition = ["uid" => 1, "network" => 'dspr'];
1382          * or:
1383          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1384          *
1385          * In either case, the provided array is left with the parameters only
1386          *
1387          * @param array $condition
1388          * @return string
1389          */
1390         public static function buildCondition(array &$condition = [])
1391         {
1392                 $condition_string = '';
1393                 if (count($condition) > 0) {
1394                         reset($condition);
1395                         $first_key = key($condition);
1396                         if (is_int($first_key)) {
1397                                 $condition_string = " WHERE (" . array_shift($condition) . ")";
1398                         } else {
1399                                 $new_values = [];
1400                                 $condition_string = "";
1401                                 foreach ($condition as $field => $value) {
1402                                         if ($condition_string != "") {
1403                                                 $condition_string .= " AND ";
1404                                         }
1405                                         if (is_array($value)) {
1406                                                 /* Workaround for MySQL Bug #64791.
1407                                                  * Never mix data types inside any IN() condition.
1408                                                  * In case of mixed types, cast all as string.
1409                                                  * Logic needs to be consistent with DBA::p() data types.
1410                                                  */
1411                                                 $is_int = false;
1412                                                 $is_alpha = false;
1413                                                 foreach ($value as $single_value) {
1414                                                         if (is_int($single_value)) {
1415                                                                 $is_int = true;
1416                                                         } else {
1417                                                                 $is_alpha = true;
1418                                                         }
1419                                                 }
1420
1421                                                 if ($is_int && $is_alpha) {
1422                                                         foreach ($value as &$ref) {
1423                                                                 if (is_int($ref)) {
1424                                                                         $ref = (string)$ref;
1425                                                                 }
1426                                                         }
1427                                                         unset($ref); //Prevent accidental re-use.
1428                                                 }
1429
1430                                                 $new_values = array_merge($new_values, array_values($value));
1431                                                 $placeholders = substr(str_repeat("?, ", count($value)), 0, -2);
1432                                                 $condition_string .= "`" . $field . "` IN (" . $placeholders . ")";
1433                                         } else {
1434                                                 $new_values[$field] = $value;
1435                                                 $condition_string .= "`" . $field . "` = ?";
1436                                         }
1437                                 }
1438                                 $condition_string = " WHERE (" . $condition_string . ")";
1439                                 $condition = $new_values;
1440                         }
1441                 }
1442
1443                 return $condition_string;
1444         }
1445
1446         /**
1447          * @brief Returns the SQL parameter string built from the provided parameter array
1448          *
1449          * @param array $params
1450          * @return string
1451          */
1452         public static function buildParameter(array $params = [])
1453         {
1454                 $order_string = '';
1455                 if (isset($params['order'])) {
1456                         $order_string = " ORDER BY ";
1457                         foreach ($params['order'] AS $fields => $order) {
1458                                 if (!is_int($fields)) {
1459                                         $order_string .= "`" . $fields . "` " . ($order ? "DESC" : "ASC") . ", ";
1460                                 } else {
1461                                         $order_string .= "`" . $order . "`, ";
1462                                 }
1463                         }
1464                         $order_string = substr($order_string, 0, -2);
1465                 }
1466
1467                 $limit_string = '';
1468                 if (isset($params['limit']) && is_int($params['limit'])) {
1469                         $limit_string = " LIMIT " . intval($params['limit']);
1470                 }
1471
1472                 if (isset($params['limit']) && is_array($params['limit'])) {
1473                         $limit_string = " LIMIT " . intval($params['limit'][0]) . ", " . intval($params['limit'][1]);
1474                 }
1475
1476                 return $order_string.$limit_string;
1477         }
1478
1479         /**
1480          * @brief Fills an array with data from a query
1481          *
1482          * @param object $stmt statement object
1483          * @return array Data array
1484          */
1485         public static function toArray($stmt, $do_close = true) {
1486                 if (is_bool($stmt)) {
1487                         return $stmt;
1488                 }
1489
1490                 $data = [];
1491                 while ($row = self::fetch($stmt)) {
1492                         $data[] = $row;
1493                 }
1494                 if ($do_close) {
1495                         self::close($stmt);
1496                 }
1497                 return $data;
1498         }
1499
1500         /**
1501          * @brief Returns the error number of the last query
1502          *
1503          * @return string Error number (0 if no error)
1504          */
1505         public static function errorNo() {
1506                 return self::$errorno;
1507         }
1508
1509         /**
1510          * @brief Returns the error message of the last query
1511          *
1512          * @return string Error message ('' if no error)
1513          */
1514         public static function errorMessage() {
1515                 return self::$error;
1516         }
1517
1518         /**
1519          * @brief Closes the current statement
1520          *
1521          * @param object $stmt statement object
1522          * @return boolean was the close successful?
1523          */
1524         public static function close($stmt) {
1525                 $a = get_app();
1526
1527                 $stamp1 = microtime(true);
1528
1529                 if (!is_object($stmt)) {
1530                         return false;
1531                 }
1532
1533                 switch (self::$driver) {
1534                         case 'pdo':
1535                                 $ret = $stmt->closeCursor();
1536                                 break;
1537                         case 'mysqli':
1538                                 // MySQLi offers both a mysqli_stmt and a mysqli_result class.
1539                                 // We should be careful not to assume the object type of $stmt
1540                                 // because DBA::p() has been able to return both types.
1541                                 if ($stmt instanceof mysqli_stmt) {
1542                                         $stmt->free_result();
1543                                         $ret = $stmt->close();
1544                                 } elseif ($stmt instanceof mysqli_result) {
1545                                         $stmt->free();
1546                                         $ret = true;
1547                                 } else {
1548                                         $ret = false;
1549                                 }
1550                                 break;
1551                 }
1552
1553                 $a->saveTimestamp($stamp1, 'database');
1554
1555                 return $ret;
1556         }
1557
1558         /**
1559          * @brief Return a list of database processes
1560          *
1561          * @return array
1562          *      'list' => List of processes, separated in their different states
1563          *      'amount' => Number of concurrent database processes
1564          */
1565         public static function processlist()
1566         {
1567                 $ret = self::p("SHOW PROCESSLIST");
1568                 $data = self::toArray($ret);
1569
1570                 $s = [];
1571
1572                 $processes = 0;
1573                 $states = [];
1574                 foreach ($data as $process) {
1575                         $state = trim($process["State"]);
1576
1577                         // Filter out all non blocking processes
1578                         if (!in_array($state, ["", "init", "statistics", "updating"])) {
1579                                 ++$states[$state];
1580                                 ++$processes;
1581                         }
1582                 }
1583
1584                 $statelist = "";
1585                 foreach ($states as $state => $usage) {
1586                         if ($statelist != "") {
1587                                 $statelist .= ", ";
1588                         }
1589                         $statelist .= $state.": ".$usage;
1590                 }
1591                 return(["list" => $statelist, "amount" => $processes]);
1592         }
1593
1594         /**
1595          * Checks if $array is a filled array with at least one entry.
1596          *
1597          * @param mixed $array A filled array with at least one entry
1598          *
1599          * @return boolean Whether $array is a filled array or an object with rows
1600          */
1601         public static function isResult($array)
1602         {
1603                 // It could be a return value from an update statement
1604                 if (is_bool($array)) {
1605                         return $array;
1606                 }
1607
1608                 if (is_object($array)) {
1609                         return self::numRows($array) > 0;
1610                 }
1611
1612                 return (is_array($array) && (count($array) > 0));
1613         }
1614
1615         /**
1616          * @brief Callback function for "esc_array"
1617          *
1618          * @param mixed   $value         Array value
1619          * @param string  $key           Array key
1620          * @param boolean $add_quotation add quotation marks for string values
1621          * @return void
1622          */
1623         private static function escapeArrayCallback(&$value, $key, $add_quotation)
1624         {
1625                 if (!$add_quotation) {
1626                         if (is_bool($value)) {
1627                                 $value = ($value ? '1' : '0');
1628                         } else {
1629                                 $value = self::escape($value);
1630                         }
1631                         return;
1632                 }
1633
1634                 if (is_bool($value)) {
1635                         $value = ($value ? 'true' : 'false');
1636                 } elseif (is_float($value) || is_integer($value)) {
1637                         $value = (string) $value;
1638                 } else {
1639                         $value = "'" . self::escape($value) . "'";
1640                 }
1641         }
1642
1643         /**
1644          * @brief Escapes a whole array
1645          *
1646          * @param mixed   $arr           Array with values to be escaped
1647          * @param boolean $add_quotation add quotation marks for string values
1648          * @return void
1649          */
1650         public static function escapeArray(&$arr, $add_quotation = false)
1651         {
1652                 array_walk($arr, 'self::escapeArrayCallback', $add_quotation);
1653         }
1654 }