src/Database/DBA.php

   1 <?php
   2
   3 namespace Friendica\Database;
   4
   5 use Friendica\Core\Config\Cache\IConfigCache;
   6 use Friendica\Core\Logger;
   7 use Friendica\Core\System;
   8 use Friendica\Util\DateTimeFormat;
   9 use Friendica\Util\Profiler;
  10 use mysqli;
  11 use mysqli_result;
  12 use mysqli_stmt;
  13 use PDO;
  14 use PDOException;
  15 use PDOStatement;
  16
  17 /**
  18  * @class MySQL database class
  19  *
  20  * This class is for the low level database stuff that does driver specific things.
  21  */
  22 class DBA
  23 {
  24         /**
  25          * Lowest possible date value
  26          */
  27         const NULL_DATE     = '0001-01-01';
  28         /**
  29          * Lowest possible datetime value
  30          */
  31         const NULL_DATETIME = '0001-01-01 00:00:00';
  32
  33         public static $connected = false;
  34
  35         /**
  36          * @var IConfigCache
  37          */
  38         private static $configCache;
  39         /**
  40          * @var Profiler
  41          */
  42         private static $profiler;
  43         /**
  44          * @var string
  45          */
  46         private static $basePath;
  47         private static $server_info = '';
  48         private static $connection;
  49         private static $driver;
  50         private static $error = false;
  51         private static $errorno = 0;
  52         private static $affected_rows = 0;
  53         private static $in_transaction = false;
  54         private static $in_retrial = false;
  55         private static $relation = [];
  56         private static $db_serveraddr = '';
  57         private static $db_user = '';
  58         private static $db_pass = '';
  59         private static $db_name = '';
  60         private static $db_charset = '';
  61
  62         public static function connect($basePath, IConfigCache $configCache, Profiler $profiler, $serveraddr, $user, $pass, $db, $charset = null)
  63         {
  64                 if (!is_null(self::$connection) && self::connected()) {
  65                         return true;
  66                 }
  67
  68                 // We are storing these values for being able to perform a reconnect
  69                 self::$basePath = $basePath;
  70                 self::$configCache = $configCache;
  71                 self::$profiler = $profiler;
  72                 self::$db_serveraddr = $serveraddr;
  73                 self::$db_user = $user;
  74                 self::$db_pass = $pass;
  75                 self::$db_name = $db;
  76                 self::$db_charset = $charset;
  77
  78                 $port = 0;
  79                 $serveraddr = trim($serveraddr);
  80
  81                 $serverdata = explode(':', $serveraddr);
  82                 $server = $serverdata[0];
  83
  84                 if (count($serverdata) > 1) {
  85                         $port = trim($serverdata[1]);
  86                 }
  87
  88                 $server = trim($server);
  89                 $user = trim($user);
  90                 $pass = trim($pass);
  91                 $db = trim($db);
  92                 $charset = trim($charset);
  93
  94                 if (!(strlen($server) && strlen($user))) {
  95                         return false;
  96                 }
  97
  98                 if (class_exists('\PDO') && in_array('mysql', PDO::getAvailableDrivers())) {
  99                         self::$driver = 'pdo';
 100                         $connect = "mysql:host=".$server.";dbname=".$db;
 101
 102                         if ($port > 0) {
 103                                 $connect .= ";port=".$port;
 104                         }
 105
 106                         if ($charset) {
 107                                 $connect .= ";charset=".$charset;
 108                         }
 109
 110                         try {
 111                                 self::$connection = @new PDO($connect, $user, $pass);
 112                                 self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
 113                                 self::$connected = true;
 114                         } catch (PDOException $e) {
 115                                 /// @TODO At least log exception, don't ignore it!
 116                         }
 117                 }
 118
 119                 if (!self::$connected && class_exists('\mysqli')) {
 120                         self::$driver = 'mysqli';
 121
 122                         if ($port > 0) {
 123                                 self::$connection = @new mysqli($server, $user, $pass, $db, $port);
 124                         } else {
 125                                 self::$connection = @new mysqli($server, $user, $pass, $db);
 126                         }
 127
 128                         if (!mysqli_connect_errno()) {
 129                                 self::$connected = true;
 130
 131                                 if ($charset) {
 132                                         self::$connection->set_charset($charset);
 133                                 }
 134                         }
 135                 }
 136
 137                 // No suitable SQL driver was found.
 138                 if (!self::$connected) {
 139                         self::$driver = null;
 140                         self::$connection = null;
 141                 }
 142
 143                 return self::$connected;
 144         }
 145
 146         /**
 147          * Disconnects the current database connection
 148          */
 149         public static function disconnect()
 150         {
 151                 if (is_null(self::$connection)) {
 152                         return;
 153                 }
 154
 155                 switch (self::$driver) {
 156                         case 'pdo':
 157                                 self::$connection = null;
 158                                 break;
 159                         case 'mysqli':
 160                                 self::$connection->close();
 161                                 self::$connection = null;
 162                                 break;
 163                 }
 164         }
 165
 166         /**
 167          * Perform a reconnect of an existing database connection
 168          */
 169         public static function reconnect() {
 170                 self::disconnect();
 171
 172                 $ret = self::connect(self::$basePath, self::$configCache, self::$profiler, self::$db_serveraddr, self::$db_user, self::$db_pass, self::$db_name, self::$db_charset);
 173                 return $ret;
 174         }
 175
 176         /**
 177          * Return the database object.
 178          * @return PDO|mysqli
 179          */
 180         public static function getConnection()
 181         {
 182                 return self::$connection;
 183         }
 184
 185         /**
 186          * @brief Returns the MySQL server version string
 187          *
 188          * This function discriminate between the deprecated mysql API and the current
 189          * object-oriented mysqli API. Example of returned string: 5.5.46-0+deb8u1
 190          *
 191          * @return string
 192          */
 193         public static function serverInfo() {
 194                 if (self::$server_info == '') {
 195                         switch (self::$driver) {
 196                                 case 'pdo':
 197                                         self::$server_info = self::$connection->getAttribute(PDO::ATTR_SERVER_VERSION);
 198                                         break;
 199                                 case 'mysqli':
 200                                         self::$server_info = self::$connection->server_info;
 201                                         break;
 202                         }
 203                 }
 204                 return self::$server_info;
 205         }
 206
 207         /**
 208          * @brief Returns the selected database name
 209          *
 210          * @return string
 211          * @throws \Exception
 212          */
 213         public static function databaseName() {
 214                 $ret = self::p("SELECT DATABASE() AS `db`");
 215                 $data = self::toArray($ret);
 216                 return $data[0]['db'];
 217         }
 218
 219         /**
 220          * @brief Analyze a database query and log this if some conditions are met.
 221          *
 222          * @param string $query The database query that will be analyzed
 223          * @throws \Exception
 224          */
 225         private static function logIndex($query) {
 226
 227                 if (!self::$configCache->get('system', 'db_log_index')) {
 228                         return;
 229                 }
 230
 231                 // Don't explain an explain statement
 232                 if (strtolower(substr($query, 0, 7)) == "explain") {
 233                         return;
 234                 }
 235
 236                 // Only do the explain on "select", "update" and "delete"
 237                 if (!in_array(strtolower(substr($query, 0, 6)), ["select", "update", "delete"])) {
 238                         return;
 239                 }
 240
 241                 $r = self::p("EXPLAIN ".$query);
 242                 if (!self::isResult($r)) {
 243                         return;
 244                 }
 245
 246                 $watchlist = explode(',', self::$configCache->get('system', 'db_log_index_watch'));
 247                 $blacklist = explode(',', self::$configCache->get('system', 'db_log_index_blacklist'));
 248
 249                 while ($row = self::fetch($r)) {
 250                         if ((intval(self::$configCache->get('system', 'db_loglimit_index')) > 0)) {
 251                                 $log = (in_array($row['key'], $watchlist) &&
 252                                         ($row['rows'] >= intval(self::$configCache->get('system', 'db_loglimit_index'))));
 253                         } else {
 254                                 $log = false;
 255                         }
 256
 257                         if ((intval(self::$configCache->get('system', 'db_loglimit_index_high')) > 0) && ($row['rows'] >= intval(self::$configCache->get('system', 'db_loglimit_index_high')))) {
 258                                 $log = true;
 259                         }
 260
 261                         if (in_array($row['key'], $blacklist) || ($row['key'] == "")) {
 262                                 $log = false;
 263                         }
 264
 265                         if ($log) {
 266                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 267                                 @file_put_contents(self::$configCache->get('system', 'db_log_index'), DateTimeFormat::utcNow()."\t".
 268                                                 $row['key']."\t".$row['rows']."\t".$row['Extra']."\t".
 269                                                 basename($backtrace[1]["file"])."\t".
 270                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 271                                                 substr($query, 0, 2000)."\n", FILE_APPEND);
 272                         }
 273                 }
 274         }
 275
 276         public static function escape($str) {
 277                 if (self::$connected) {
 278                         switch (self::$driver) {
 279                                 case 'pdo':
 280                                         return substr(@self::$connection->quote($str, PDO::PARAM_STR), 1, -1);
 281
 282                                 case 'mysqli':
 283                                         return @self::$connection->real_escape_string($str);
 284                         }
 285                 } else {
 286                         return str_replace("'", "\\'", $str);
 287                 }
 288         }
 289
 290         public static function connected() {
 291                 $connected = false;
 292
 293                 if (is_null(self::$connection)) {
 294                         return false;
 295                 }
 296
 297                 switch (self::$driver) {
 298                         case 'pdo':
 299                                 $r = self::p("SELECT 1");
 300                                 if (self::isResult($r)) {
 301                                         $row = self::toArray($r);
 302                                         $connected = ($row[0]['1'] == '1');
 303                                 }
 304                                 break;
 305                         case 'mysqli':
 306                                 $connected = self::$connection->ping();
 307                                 break;
 308                 }
 309                 return $connected;
 310         }
 311
 312         /**
 313          * @brief Replaces ANY_VALUE() function by MIN() function,
 314          *  if the database server does not support ANY_VALUE().
 315          *
 316          * Considerations for Standard SQL, or MySQL with ONLY_FULL_GROUP_BY (default since 5.7.5).
 317          * ANY_VALUE() is available from MySQL 5.7.5 https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html
 318          * A standard fall-back is to use MIN().
 319          *
 320          * @param string $sql An SQL string without the values
 321          * @return string The input SQL string modified if necessary.
 322          */
 323         public static function anyValueFallback($sql) {
 324                 $server_info = self::serverInfo();
 325                 if (version_compare($server_info, '5.7.5', '<') ||
 326                         (stripos($server_info, 'MariaDB') !== false)) {
 327                         $sql = str_ireplace('ANY_VALUE(', 'MIN(', $sql);
 328                 }
 329                 return $sql;
 330         }
 331
 332         /**
 333          * @brief beautifies the query - useful for "SHOW PROCESSLIST"
 334          *
 335          * This is safe when we bind the parameters later.
 336          * The parameter values aren't part of the SQL.
 337          *
 338          * @param string $sql An SQL string without the values
 339          * @return string The input SQL string modified if necessary.
 340          */
 341         public static function cleanQuery($sql) {
 342                 $search = ["\t", "\n", "\r", "  "];
 343                 $replace = [' ', ' ', ' ', ' '];
 344                 do {
 345                         $oldsql = $sql;
 346                         $sql = str_replace($search, $replace, $sql);
 347                 } while ($oldsql != $sql);
 348
 349                 return $sql;
 350         }
 351
 352
 353         /**
 354          * @brief Replaces the ? placeholders with the parameters in the $args array
 355          *
 356          * @param string $sql SQL query
 357          * @param array $args The parameters that are to replace the ? placeholders
 358          * @return string The replaced SQL query
 359          */
 360         private static function replaceParameters($sql, $args) {
 361                 $offset = 0;
 362                 foreach ($args AS $param => $value) {
 363                         if (is_int($args[$param]) || is_float($args[$param])) {
 364                                 $replace = intval($args[$param]);
 365                         } else {
 366                                 $replace = "'".self::escape($args[$param])."'";
 367                         }
 368
 369                         $pos = strpos($sql, '?', $offset);
 370                         if ($pos !== false) {
 371                                 $sql = substr_replace($sql, $replace, $pos, 1);
 372                         }
 373                         $offset = $pos + strlen($replace);
 374                 }
 375                 return $sql;
 376         }
 377
 378         /**
 379          * @brief Convert parameter array to an universal form
 380          * @param array $args Parameter array
 381          * @return array universalized parameter array
 382          */
 383         private static function getParam($args) {
 384                 unset($args[0]);
 385
 386                 // When the second function parameter is an array then use this as the parameter array
 387                 if ((count($args) > 0) && (is_array($args[1]))) {
 388                         return $args[1];
 389                 } else {
 390                         return $args;
 391                 }
 392         }
 393
 394         /**
 395          * @brief Executes a prepared statement that returns data
 396          * @usage Example: $r = p("SELECT * FROM `item` WHERE `guid` = ?", $guid);
 397          *
 398          * Please only use it with complicated queries.
 399          * For all regular queries please use DBA::select or DBA::exists
 400          *
 401          * @param string $sql SQL statement
 402          * @return bool|object statement object or result object
 403          * @throws \Exception
 404          */
 405         public static function p($sql) {
 406
 407                 $stamp1 = microtime(true);
 408
 409                 $params = self::getParam(func_get_args());
 410
 411                 // Renumber the array keys to be sure that they fit
 412                 $i = 0;
 413                 $args = [];
 414                 foreach ($params AS $param) {
 415                         // Avoid problems with some MySQL servers and boolean values. See issue #3645
 416                         if (is_bool($param)) {
 417                                 $param = (int)$param;
 418                         }
 419                         $args[++$i] = $param;
 420                 }
 421
 422                 if (!self::$connected) {
 423                         return false;
 424                 }
 425
 426                 if ((substr_count($sql, '?') != count($args)) && (count($args) > 0)) {
 427                         // Question: Should we continue or stop the query here?
 428                         Logger::warning('Query parameters mismatch.', ['query' => $sql, 'args' => $args, 'callstack' => System::callstack()]);
 429                 }
 430
 431                 $sql = self::cleanQuery($sql);
 432                 $sql = self::anyValueFallback($sql);
 433
 434                 $orig_sql = $sql;
 435
 436                 if (self::$configCache->get('system', 'db_callstack') !== null) {
 437                         $sql = "/*".System::callstack()." */ ".$sql;
 438                 }
 439
 440                 self::$error = '';
 441                 self::$errorno = 0;
 442                 self::$affected_rows = 0;
 443
 444                 // We have to make some things different if this function is called from "e"
 445                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
 446
 447                 if (isset($trace[1])) {
 448                         $called_from = $trace[1];
 449                 } else {
 450                         // We use just something that is defined to avoid warnings
 451                         $called_from = $trace[0];
 452                 }
 453                 // We are having an own error logging in the function "e"
 454                 $called_from_e = ($called_from['function'] == 'e');
 455
 456                 switch (self::$driver) {
 457                         case 'pdo':
 458                                 // If there are no arguments we use "query"
 459                                 if (count($args) == 0) {
 460                                         if (!$retval = self::$connection->query($sql)) {
 461                                                 $errorInfo = self::$connection->errorInfo();
 462                                                 self::$error = $errorInfo[2];
 463                                                 self::$errorno = $errorInfo[1];
 464                                                 $retval = false;
 465                                                 break;
 466                                         }
 467                                         self::$affected_rows = $retval->rowCount();
 468                                         break;
 469                                 }
 470
 471                                 if (!$stmt = self::$connection->prepare($sql)) {
 472                                         $errorInfo = self::$connection->errorInfo();
 473                                         self::$error = $errorInfo[2];
 474                                         self::$errorno = $errorInfo[1];
 475                                         $retval = false;
 476                                         break;
 477                                 }
 478
 479                                 foreach ($args AS $param => $value) {
 480                                         if (is_int($args[$param])) {
 481                                                 $data_type = PDO::PARAM_INT;
 482                                         } else {
 483                                                 $data_type = PDO::PARAM_STR;
 484                                         }
 485                                         $stmt->bindParam($param, $args[$param], $data_type);
 486                                 }
 487
 488                                 if (!$stmt->execute()) {
 489                                         $errorInfo = $stmt->errorInfo();
 490                                         self::$error = $errorInfo[2];
 491                                         self::$errorno = $errorInfo[1];
 492                                         $retval = false;
 493                                 } else {
 494                                         $retval = $stmt;
 495                                         self::$affected_rows = $retval->rowCount();
 496                                 }
 497                                 break;
 498                         case 'mysqli':
 499                                 // There are SQL statements that cannot be executed with a prepared statement
 500                                 $parts = explode(' ', $orig_sql);
 501                                 $command = strtolower($parts[0]);
 502                                 $can_be_prepared = in_array($command, ['select', 'update', 'insert', 'delete']);
 503
 504                                 // The fallback routine is called as well when there are no arguments
 505                                 if (!$can_be_prepared || (count($args) == 0)) {
 506                                         $retval = self::$connection->query(self::replaceParameters($sql, $args));
 507                                         if (self::$connection->errno) {
 508                                                 self::$error = self::$connection->error;
 509                                                 self::$errorno = self::$connection->errno;
 510                                                 $retval = false;
 511                                         } else {
 512                                                 if (isset($retval->num_rows)) {
 513                                                         self::$affected_rows = $retval->num_rows;
 514                                                 } else {
 515                                                         self::$affected_rows = self::$connection->affected_rows;
 516                                                 }
 517                                         }
 518                                         break;
 519                                 }
 520
 521                                 $stmt = self::$connection->stmt_init();
 522
 523                                 if (!$stmt->prepare($sql)) {
 524                                         self::$error = $stmt->error;
 525                                         self::$errorno = $stmt->errno;
 526                                         $retval = false;
 527                                         break;
 528                                 }
 529
 530                                 $param_types = '';
 531                                 $values = [];
 532                                 foreach ($args AS $param => $value) {
 533                                         if (is_int($args[$param])) {
 534                                                 $param_types .= 'i';
 535                                         } elseif (is_float($args[$param])) {
 536                                                 $param_types .= 'd';
 537                                         } elseif (is_string($args[$param])) {
 538                                                 $param_types .= 's';
 539                                         } else {
 540                                                 $param_types .= 'b';
 541                                         }
 542                                         $values[] = &$args[$param];
 543                                 }
 544
 545                                 if (count($values) > 0) {
 546                                         array_unshift($values, $param_types);
 547                                         call_user_func_array([$stmt, 'bind_param'], $values);
 548                                 }
 549
 550                                 if (!$stmt->execute()) {
 551                                         self::$error = self::$connection->error;
 552                                         self::$errorno = self::$connection->errno;
 553                                         $retval = false;
 554                                 } else {
 555                                         $stmt->store_result();
 556                                         $retval = $stmt;
 557                                         self::$affected_rows = $retval->affected_rows;
 558                                 }
 559                                 break;
 560                 }
 561
 562                 // We are having an own error logging in the function "e"
 563                 if ((self::$errorno != 0) && !$called_from_e) {
 564                         // We have to preserve the error code, somewhere in the logging it get lost
 565                         $error = self::$error;
 566                         $errorno = self::$errorno;
 567
 568                         Logger::log('DB Error '.self::$errorno.': '.self::$error."\n".
 569                                 System::callstack(8)."\n".self::replaceParameters($sql, $args));
 570
 571                         // On a lost connection we try to reconnect - but only once.
 572                         if ($errorno == 2006) {
 573                                 if (self::$in_retrial || !self::reconnect()) {
 574                                         // It doesn't make sense to continue when the database connection was lost
 575                                         if (self::$in_retrial) {
 576                                                 Logger::log('Giving up retrial because of database error '.$errorno.': '.$error);
 577                                         } else {
 578                                                 Logger::log("Couldn't reconnect after database error ".$errorno.': '.$error);
 579                                         }
 580                                         exit(1);
 581                                 } else {
 582                                         // We try it again
 583                                         Logger::log('Reconnected after database error '.$errorno.': '.$error);
 584                                         self::$in_retrial = true;
 585                                         $ret = self::p($sql, $args);
 586                                         self::$in_retrial = false;
 587                                         return $ret;
 588                                 }
 589                         }
 590
 591                         self::$error = $error;
 592                         self::$errorno = $errorno;
 593                 }
 594
 595                 self::$profiler->saveTimestamp($stamp1, 'database', System::callstack());
 596
 597                 if (self::$configCache->get('system', 'db_log')) {
 598                         $stamp2 = microtime(true);
 599                         $duration = (float)($stamp2 - $stamp1);
 600
 601                         if (($duration > self::$configCache->get('system', 'db_loglimit'))) {
 602                                 $duration = round($duration, 3);
 603                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 604
 605                                 @file_put_contents(self::$configCache->get('system', 'db_log'), DateTimeFormat::utcNow()."\t".$duration."\t".
 606                                                 basename($backtrace[1]["file"])."\t".
 607                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 608                                                 substr(self::replaceParameters($sql, $args), 0, 2000)."\n", FILE_APPEND);
 609                         }
 610                 }
 611                 return $retval;
 612         }
 613
 614         /**
 615          * @brief Executes a prepared statement like UPDATE or INSERT that doesn't return data
 616          *
 617          * Please use DBA::delete, DBA::insert, DBA::update, ... instead
 618          *
 619          * @param string $sql SQL statement
 620          * @return boolean Was the query successfull? False is returned only if an error occurred
 621          * @throws \Exception
 622          */
 623         public static function e($sql) {
 624
 625                 $stamp = microtime(true);
 626
 627                 $params = self::getParam(func_get_args());
 628
 629                 // In a case of a deadlock we are repeating the query 20 times
 630                 $timeout = 20;
 631
 632                 do {
 633                         $stmt = self::p($sql, $params);
 634
 635                         if (is_bool($stmt)) {
 636                                 $retval = $stmt;
 637                         } elseif (is_object($stmt)) {
 638                                 $retval = true;
 639                         } else {
 640                                 $retval = false;
 641                         }
 642
 643                         self::close($stmt);
 644
 645                 } while ((self::$errorno == 1213) && (--$timeout > 0));
 646
 647                 if (self::$errorno != 0) {
 648                         // We have to preserve the error code, somewhere in the logging it get lost
 649                         $error = self::$error;
 650                         $errorno = self::$errorno;
 651
 652                         Logger::log('DB Error '.self::$errorno.': '.self::$error."\n".
 653                                 System::callstack(8)."\n".self::replaceParameters($sql, $params));
 654
 655                         // On a lost connection we simply quit.
 656                         // A reconnect like in self::p could be dangerous with modifications
 657                         if ($errorno == 2006) {
 658                                 Logger::log('Giving up because of database error '.$errorno.': '.$error);
 659                                 exit(1);
 660                         }
 661
 662                         self::$error = $error;
 663                         self::$errorno = $errorno;
 664                 }
 665
 666                 self::$profiler->saveTimestamp($stamp, "database_write", System::callstack());
 667
 668                 return $retval;
 669         }
 670
 671         /**
 672          * @brief Check if data exists
 673          *
 674          * @param string $table     Table name
 675          * @param array  $condition array of fields for condition
 676          *
 677          * @return boolean Are there rows for that condition?
 678          * @throws \Exception
 679          */
 680         public static function exists($table, $condition) {
 681                 if (empty($table)) {
 682                         return false;
 683                 }
 684
 685                 $fields = [];
 686
 687                 if (empty($condition)) {
 688                         return DBStructure::existsTable($table);
 689                 }
 690
 691                 reset($condition);
 692                 $first_key = key($condition);
 693                 if (!is_int($first_key)) {
 694                         $fields = [$first_key];
 695                 }
 696
 697                 $stmt = self::select($table, $fields, $condition, ['limit' => 1]);
 698
 699                 if (is_bool($stmt)) {
 700                         $retval = $stmt;
 701                 } else {
 702                         $retval = (self::numRows($stmt) > 0);
 703                 }
 704
 705                 self::close($stmt);
 706
 707                 return $retval;
 708         }
 709
 710         /**
 711          * Fetches the first row
 712          *
 713          * Please use DBA::selectFirst or DBA::exists whenever this is possible.
 714          *
 715          * @brief Fetches the first row
 716          * @param string $sql SQL statement
 717          * @return array first row of query
 718          * @throws \Exception
 719          */
 720         public static function fetchFirst($sql) {
 721                 $params = self::getParam(func_get_args());
 722
 723                 $stmt = self::p($sql, $params);
 724
 725                 if (is_bool($stmt)) {
 726                         $retval = $stmt;
 727                 } else {
 728                         $retval = self::fetch($stmt);
 729                 }
 730
 731                 self::close($stmt);
 732
 733                 return $retval;
 734         }
 735
 736         /**
 737          * @brief Returns the number of affected rows of the last statement
 738          *
 739          * @return int Number of rows
 740          */
 741         public static function affectedRows() {
 742                 return self::$affected_rows;
 743         }
 744
 745         /**
 746          * @brief Returns the number of columns of a statement
 747          *
 748          * @param object Statement object
 749          * @return int Number of columns
 750          */
 751         public static function columnCount($stmt) {
 752                 if (!is_object($stmt)) {
 753                         return 0;
 754                 }
 755                 switch (self::$driver) {
 756                         case 'pdo':
 757                                 return $stmt->columnCount();
 758                         case 'mysqli':
 759                                 return $stmt->field_count;
 760                 }
 761                 return 0;
 762         }
 763         /**
 764          * @brief Returns the number of rows of a statement
 765          *
 766          * @param PDOStatement|mysqli_result|mysqli_stmt Statement object
 767          * @return int Number of rows
 768          */
 769         public static function numRows($stmt) {
 770                 if (!is_object($stmt)) {
 771                         return 0;
 772                 }
 773                 switch (self::$driver) {
 774                         case 'pdo':
 775                                 return $stmt->rowCount();
 776                         case 'mysqli':
 777                                 return $stmt->num_rows;
 778                 }
 779                 return 0;
 780         }
 781
 782         /**
 783          * @brief Fetch a single row
 784          *
 785          * @param mixed $stmt statement object
 786          * @return array current row
 787          */
 788         public static function fetch($stmt) {
 789
 790                 $stamp1 = microtime(true);
 791
 792                 $columns = [];
 793
 794                 if (!is_object($stmt)) {
 795                         return false;
 796                 }
 797
 798                 switch (self::$driver) {
 799                         case 'pdo':
 800                                 $columns = $stmt->fetch(PDO::FETCH_ASSOC);
 801                                 break;
 802                         case 'mysqli':
 803                                 if (get_class($stmt) == 'mysqli_result') {
 804                                         $columns = $stmt->fetch_assoc();
 805                                         break;
 806                                 }
 807
 808                                 // This code works, but is slow
 809
 810                                 // Bind the result to a result array
 811                                 $cols = [];
 812
 813                                 $cols_num = [];
 814                                 for ($x = 0; $x < $stmt->field_count; $x++) {
 815                                         $cols[] = &$cols_num[$x];
 816                                 }
 817
 818                                 call_user_func_array([$stmt, 'bind_result'], $cols);
 819
 820                                 if (!$stmt->fetch()) {
 821                                         return false;
 822                                 }
 823
 824                                 // The slow part:
 825                                 // We need to get the field names for the array keys
 826                                 // It seems that there is no better way to do this.
 827                                 $result = $stmt->result_metadata();
 828                                 $fields = $result->fetch_fields();
 829
 830                                 foreach ($cols_num AS $param => $col) {
 831                                         $columns[$fields[$param]->name] = $col;
 832                                 }
 833                 }
 834
 835                 self::$profiler->saveTimestamp($stamp1, 'database', System::callstack());
 836
 837                 return $columns;
 838         }
 839
 840         /**
 841          * @brief Insert a row into a table
 842          *
 843          * @param string $table               Table name
 844          * @param array  $param               parameter array
 845          * @param bool   $on_duplicate_update Do an update on a duplicate entry
 846          *
 847          * @return boolean was the insert successful?
 848          * @throws \Exception
 849          */
 850         public static function insert($table, $param, $on_duplicate_update = false) {
 851
 852                 if (empty($table) || empty($param)) {
 853                         Logger::log('Table and fields have to be set');
 854                         return false;
 855                 }
 856
 857                 $sql = "INSERT INTO `".self::escape($table)."` (`".implode("`, `", array_keys($param))."`) VALUES (".
 858                         substr(str_repeat("?, ", count($param)), 0, -2).")";
 859
 860                 if ($on_duplicate_update) {
 861                         $sql .= " ON DUPLICATE KEY UPDATE `".implode("` = ?, `", array_keys($param))."` = ?";
 862
 863                         $values = array_values($param);
 864                         $param = array_merge_recursive($values, $values);
 865                 }
 866
 867                 return self::e($sql, $param);
 868         }
 869
 870         /**
 871          * @brief Fetch the id of the last insert command
 872          *
 873          * @return integer Last inserted id
 874          */
 875         public static function lastInsertId() {
 876                 switch (self::$driver) {
 877                         case 'pdo':
 878                                 $id = self::$connection->lastInsertId();
 879                                 break;
 880                         case 'mysqli':
 881                                 $id = self::$connection->insert_id;
 882                                 break;
 883                 }
 884                 return $id;
 885         }
 886
 887         /**
 888          * @brief Locks a table for exclusive write access
 889          *
 890          * This function can be extended in the future to accept a table array as well.
 891          *
 892          * @param string $table Table name
 893          *
 894          * @return boolean was the lock successful?
 895          * @throws \Exception
 896          */
 897         public static function lock($table) {
 898                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
 899                 if (self::$driver == 'pdo') {
 900                         self::e("SET autocommit=0");
 901                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
 902                 } else {
 903                         self::$connection->autocommit(false);
 904                 }
 905
 906                 $success = self::e("LOCK TABLES `".self::escape($table)."` WRITE");
 907
 908                 if (self::$driver == 'pdo') {
 909                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
 910                 }
 911
 912                 if (!$success) {
 913                         if (self::$driver == 'pdo') {
 914                                 self::e("SET autocommit=1");
 915                         } else {
 916                                 self::$connection->autocommit(true);
 917                         }
 918                 } else {
 919                         self::$in_transaction = true;
 920                 }
 921                 return $success;
 922         }
 923
 924         /**
 925          * @brief Unlocks all locked tables
 926          *
 927          * @return boolean was the unlock successful?
 928          * @throws \Exception
 929          */
 930         public static function unlock() {
 931                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
 932                 self::performCommit();
 933
 934                 if (self::$driver == 'pdo') {
 935                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
 936                 }
 937
 938                 $success = self::e("UNLOCK TABLES");
 939
 940                 if (self::$driver == 'pdo') {
 941                         self::$connection->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
 942                         self::e("SET autocommit=1");
 943                 } else {
 944                         self::$connection->autocommit(true);
 945                 }
 946
 947                 self::$in_transaction = false;
 948                 return $success;
 949         }
 950
 951         /**
 952          * @brief Starts a transaction
 953          *
 954          * @return boolean Was the command executed successfully?
 955          */
 956         public static function transaction() {
 957                 if (!self::performCommit()) {
 958                         return false;
 959                 }
 960
 961                 switch (self::$driver) {
 962                         case 'pdo':
 963                                 if (!self::$connection->inTransaction() && !self::$connection->beginTransaction()) {
 964                                         return false;
 965                                 }
 966                                 break;
 967
 968                         case 'mysqli':
 969                                 if (!self::$connection->begin_transaction()) {
 970                                         return false;
 971                                 }
 972                                 break;
 973                 }
 974
 975                 self::$in_transaction = true;
 976                 return true;
 977         }
 978
 979         private static function performCommit()
 980         {
 981                 switch (self::$driver) {
 982                         case 'pdo':
 983                                 if (!self::$connection->inTransaction()) {
 984                                         return true;
 985                                 }
 986
 987                                 return self::$connection->commit();
 988
 989                         case 'mysqli':
 990                                 return self::$connection->commit();
 991                 }
 992
 993                 return true;
 994         }
 995
 996         /**
 997          * @brief Does a commit
 998          *
 999          * @return boolean Was the command executed successfully?
1000          */
1001         public static function commit() {
1002                 if (!self::performCommit()) {
1003                         return false;
1004                 }
1005                 self::$in_transaction = false;
1006                 return true;
1007         }
1008
1009         /**
1010          * @brief Does a rollback
1011          *
1012          * @return boolean Was the command executed successfully?
1013          */
1014         public static function rollback() {
1015                 $ret = false;
1016
1017                 switch (self::$driver) {
1018                         case 'pdo':
1019                                 if (!self::$connection->inTransaction()) {
1020                                         $ret = true;
1021                                         break;
1022                                 }
1023                                 $ret = self::$connection->rollBack();
1024                                 break;
1025
1026                         case 'mysqli':
1027                                 $ret = self::$connection->rollback();
1028                                 break;
1029                 }
1030                 self::$in_transaction = false;
1031                 return $ret;
1032         }
1033
1034         /**
1035          * @brief Build the array with the table relations
1036          *
1037          * The array is build from the database definitions in DBStructure.php
1038          *
1039          * This process must only be started once, since the value is cached.
1040          */
1041         private static function buildRelationData() {
1042                 $definition = DBStructure::definition(self::$basePath);
1043
1044                 foreach ($definition AS $table => $structure) {
1045                         foreach ($structure['fields'] AS $field => $field_struct) {
1046                                 if (isset($field_struct['relation'])) {
1047                                         foreach ($field_struct['relation'] AS $rel_table => $rel_field) {
1048                                                 self::$relation[$rel_table][$rel_field][$table][] = $field;
1049                                         }
1050                                 }
1051                         }
1052                 }
1053         }
1054
1055         /**
1056          * @brief Delete a row from a table
1057          *
1058          * @param string $table      Table name
1059          * @param array  $conditions Field condition(s)
1060          * @param array  $options
1061          *                           - cascade: If true we delete records in other tables that depend on the one we're deleting through
1062          *                           relations (default: true)
1063          * @param array  $callstack  Internal use: prevent endless loops
1064          *
1065          * @return boolean was the delete successful?
1066          * @throws \Exception
1067          */
1068         public static function delete($table, array $conditions, array $options = [], array &$callstack = [])
1069         {
1070                 if (empty($table) || empty($conditions)) {
1071                         Logger::log('Table and conditions have to be set');
1072                         return false;
1073                 }
1074
1075                 $commands = [];
1076
1077                 // Create a key for the loop prevention
1078                 $key = $table . ':' . json_encode($conditions);
1079
1080                 // We quit when this key already exists in the callstack.
1081                 if (isset($callstack[$key])) {
1082                         return $commands;
1083                 }
1084
1085                 $callstack[$key] = true;
1086
1087                 $table = self::escape($table);
1088
1089                 $commands[$key] = ['table' => $table, 'conditions' => $conditions];
1090
1091                 // Don't use "defaults" here, since it would set "false" to "true"
1092                 if (isset($options['cascade'])) {
1093                         $cascade = $options['cascade'];
1094                 } else {
1095                         $cascade = true;
1096                 }
1097
1098                 // To speed up the whole process we cache the table relations
1099                 if ($cascade && count(self::$relation) == 0) {
1100                         self::buildRelationData();
1101                 }
1102
1103                 // Is there a relation entry for the table?
1104                 if ($cascade && isset(self::$relation[$table])) {
1105                         // We only allow a simple "one field" relation.
1106                         $field = array_keys(self::$relation[$table])[0];
1107                         $rel_def = array_values(self::$relation[$table])[0];
1108
1109                         // Create a key for preventing double queries
1110                         $qkey = $field . '-' . $table . ':' . json_encode($conditions);
1111
1112                         // When the search field is the relation field, we don't need to fetch the rows
1113                         // This is useful when the leading record is already deleted in the frontend but the rest is done in the backend
1114                         if ((count($conditions) == 1) && ($field == array_keys($conditions)[0])) {
1115                                 foreach ($rel_def AS $rel_table => $rel_fields) {
1116                                         foreach ($rel_fields AS $rel_field) {
1117                                                 self::delete($rel_table, [$rel_field => array_values($conditions)[0]], $options, $callstack);
1118                                         }
1119                                 }
1120                                 // We quit when this key already exists in the callstack.
1121                         } elseif (!isset($callstack[$qkey])) {
1122                                 $callstack[$qkey] = true;
1123
1124                                 // Fetch all rows that are to be deleted
1125                                 $data = self::select($table, [$field], $conditions);
1126
1127                                 while ($row = self::fetch($data)) {
1128                                         self::delete($table, [$field => $row[$field]], $options, $callstack);
1129                                 }
1130
1131                                 self::close($data);
1132
1133                                 // Since we had split the delete command we don't need the original command anymore
1134                                 unset($commands[$key]);
1135                         }
1136                 }
1137
1138                 // Now we finalize the process
1139                 $do_transaction = !self::$in_transaction;
1140
1141                 if ($do_transaction) {
1142                         self::transaction();
1143                 }
1144
1145                 $compacted = [];
1146                 $counter = [];
1147
1148                 foreach ($commands AS $command) {
1149                         $conditions = $command['conditions'];
1150                         reset($conditions);
1151                         $first_key = key($conditions);
1152
1153                         $condition_string = self::buildCondition($conditions);
1154
1155                         if ((count($command['conditions']) > 1) || is_int($first_key)) {
1156                                 $sql = "DELETE FROM `" . $command['table'] . "`" . $condition_string;
1157                                 Logger::log(self::replaceParameters($sql, $conditions), Logger::DATA);
1158
1159                                 if (!self::e($sql, $conditions)) {
1160                                         if ($do_transaction) {
1161                                                 self::rollback();
1162                                         }
1163                                         return false;
1164                                 }
1165                         } else {
1166                                 $key_table = $command['table'];
1167                                 $key_condition = array_keys($command['conditions'])[0];
1168                                 $value = array_values($command['conditions'])[0];
1169
1170                                 // Split the SQL queries in chunks of 100 values
1171                                 // We do the $i stuff here to make the code better readable
1172                                 $i = isset($counter[$key_table][$key_condition]) ? $counter[$key_table][$key_condition] : 0;
1173                                 if (isset($compacted[$key_table][$key_condition][$i]) && count($compacted[$key_table][$key_condition][$i]) > 100) {
1174                                         ++$i;
1175                                 }
1176
1177                                 $compacted[$key_table][$key_condition][$i][$value] = $value;
1178                                 $counter[$key_table][$key_condition] = $i;
1179                         }
1180                 }
1181                 foreach ($compacted AS $table => $values) {
1182                         foreach ($values AS $field => $field_value_list) {
1183                                 foreach ($field_value_list AS $field_values) {
1184                                         $sql = "DELETE FROM `" . $table . "` WHERE `" . $field . "` IN (" .
1185                                                 substr(str_repeat("?, ", count($field_values)), 0, -2) . ");";
1186
1187                                         Logger::log(self::replaceParameters($sql, $field_values), Logger::DATA);
1188
1189                                         if (!self::e($sql, $field_values)) {
1190                                                 if ($do_transaction) {
1191                                                         self::rollback();
1192                                                 }
1193                                                 return false;
1194                                         }
1195                                 }
1196                         }
1197                 }
1198                 if ($do_transaction) {
1199                         self::commit();
1200                 }
1201                 return true;
1202         }
1203
1204         /**
1205          * @brief Updates rows
1206          *
1207          * Updates rows in the database. When $old_fields is set to an array,
1208          * the system will only do an update if the fields in that array changed.
1209          *
1210          * Attention:
1211          * Only the values in $old_fields are compared.
1212          * This is an intentional behaviour.
1213          *
1214          * Example:
1215          * We include the timestamp field in $fields but not in $old_fields.
1216          * Then the row will only get the new timestamp when the other fields had changed.
1217          *
1218          * When $old_fields is set to a boolean value the system will do this compare itself.
1219          * When $old_fields is set to "true" the system will do an insert if the row doesn't exists.
1220          *
1221          * Attention:
1222          * Only set $old_fields to a boolean value when you are sure that you will update a single row.
1223          * When you set $old_fields to "true" then $fields must contain all relevant fields!
1224          *
1225          * @param string        $table      Table name
1226          * @param array         $fields     contains the fields that are updated
1227          * @param array         $condition  condition array with the key values
1228          * @param array|boolean $old_fields array with the old field values that are about to be replaced (true = update on duplicate)
1229          *
1230          * @return boolean was the update successfull?
1231          * @throws \Exception
1232          */
1233         public static function update($table, $fields, $condition, $old_fields = []) {
1234
1235                 if (empty($table) || empty($fields) || empty($condition)) {
1236                         Logger::log('Table, fields and condition have to be set');
1237                         return false;
1238                 }
1239
1240                 $table = self::escape($table);
1241
1242                 $condition_string = self::buildCondition($condition);
1243
1244                 if (is_bool($old_fields)) {
1245                         $do_insert = $old_fields;
1246
1247                         $old_fields = self::selectFirst($table, [], $condition);
1248
1249                         if (is_bool($old_fields)) {
1250                                 if ($do_insert) {
1251                                         $values = array_merge($condition, $fields);
1252                                         return self::insert($table, $values, $do_insert);
1253                                 }
1254                                 $old_fields = [];
1255                         }
1256                 }
1257
1258                 $do_update = (count($old_fields) == 0);
1259
1260                 foreach ($old_fields AS $fieldname => $content) {
1261                         if (isset($fields[$fieldname])) {
1262                                 if (($fields[$fieldname] == $content) && !is_null($content)) {
1263                                         unset($fields[$fieldname]);
1264                                 } else {
1265                                         $do_update = true;
1266                                 }
1267                         }
1268                 }
1269
1270                 if (!$do_update || (count($fields) == 0)) {
1271                         return true;
1272                 }
1273
1274                 $sql = "UPDATE `".$table."` SET `".
1275                         implode("` = ?, `", array_keys($fields))."` = ?".$condition_string;
1276
1277                 $params1 = array_values($fields);
1278                 $params2 = array_values($condition);
1279                 $params = array_merge_recursive($params1, $params2);
1280
1281                 return self::e($sql, $params);
1282         }
1283
1284         /**
1285          * Retrieve a single record from a table and returns it in an associative array
1286          *
1287          * @brief Retrieve a single record from a table
1288          * @param string $table
1289          * @param array  $fields
1290          * @param array  $condition
1291          * @param array  $params
1292          * @return bool|array
1293          * @throws \Exception
1294          * @see   self::select
1295          */
1296         public static function selectFirst($table, array $fields = [], array $condition = [], $params = [])
1297         {
1298                 $params['limit'] = 1;
1299                 $result = self::select($table, $fields, $condition, $params);
1300
1301                 if (is_bool($result)) {
1302                         return $result;
1303                 } else {
1304                         $row = self::fetch($result);
1305                         self::close($result);
1306                         return $row;
1307                 }
1308         }
1309
1310         /**
1311          * @brief Select rows from a table
1312          *
1313          * @param string $table     Table name
1314          * @param array  $fields    Array of selected fields, empty for all
1315          * @param array  $condition Array of fields for condition
1316          * @param array  $params    Array of several parameters
1317          *
1318          * @return boolean|object
1319          *
1320          * Example:
1321          * $table = "item";
1322          * $fields = array("id", "uri", "uid", "network");
1323          *
1324          * $condition = array("uid" => 1, "network" => 'dspr');
1325          * or:
1326          * $condition = array("`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr');
1327          *
1328          * $params = array("order" => array("id", "received" => true), "limit" => 10);
1329          *
1330          * $data = DBA::select($table, $fields, $condition, $params);
1331          * @throws \Exception
1332          */
1333         public static function select($table, array $fields = [], array $condition = [], array $params = [])
1334         {
1335                 if ($table == '') {
1336                         return false;
1337                 }
1338
1339                 $table = self::escape($table);
1340
1341                 if (count($fields) > 0) {
1342                         $select_fields = "`" . implode("`, `", array_values($fields)) . "`";
1343                 } else {
1344                         $select_fields = "*";
1345                 }
1346
1347                 $condition_string = self::buildCondition($condition);
1348
1349                 $param_string = self::buildParameter($params);
1350
1351                 $sql = "SELECT " . $select_fields . " FROM `" . $table . "`" . $condition_string . $param_string;
1352
1353                 $result = self::p($sql, $condition);
1354
1355                 return $result;
1356         }
1357
1358         /**
1359          * @brief Counts the rows from a table satisfying the provided condition
1360          *
1361          * @param string $table     Table name
1362          * @param array  $condition array of fields for condition
1363          *
1364          * @return int
1365          *
1366          * Example:
1367          * $table = "item";
1368          *
1369          * $condition = ["uid" => 1, "network" => 'dspr'];
1370          * or:
1371          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1372          *
1373          * $count = DBA::count($table, $condition);
1374          * @throws \Exception
1375          */
1376         public static function count($table, array $condition = [])
1377         {
1378                 if ($table == '') {
1379                         return false;
1380                 }
1381
1382                 $condition_string = self::buildCondition($condition);
1383
1384                 $sql = "SELECT COUNT(*) AS `count` FROM `".$table."`".$condition_string;
1385
1386                 $row = self::fetchFirst($sql, $condition);
1387
1388                 return $row['count'];
1389         }
1390
1391         /**
1392          * @brief Returns the SQL condition string built from the provided condition array
1393          *
1394          * This function operates with two modes.
1395          * - Supplied with a filed/value associative array, it builds simple strict
1396          *   equality conditions linked by AND.
1397          * - Supplied with a flat list, the first element is the condition string and
1398          *   the following arguments are the values to be interpolated
1399          *
1400          * $condition = ["uid" => 1, "network" => 'dspr'];
1401          * or:
1402          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1403          *
1404          * In either case, the provided array is left with the parameters only
1405          *
1406          * @param array $condition
1407          * @return string
1408          */
1409         public static function buildCondition(array &$condition = [])
1410         {
1411                 $condition_string = '';
1412                 if (count($condition) > 0) {
1413                         reset($condition);
1414                         $first_key = key($condition);
1415                         if (is_int($first_key)) {
1416                                 $condition_string = " WHERE (" . array_shift($condition) . ")";
1417                         } else {
1418                                 $new_values = [];
1419                                 $condition_string = "";
1420                                 foreach ($condition as $field => $value) {
1421                                         if ($condition_string != "") {
1422                                                 $condition_string .= " AND ";
1423                                         }
1424                                         if (is_array($value)) {
1425                                                 /* Workaround for MySQL Bug #64791.
1426                                                  * Never mix data types inside any IN() condition.
1427                                                  * In case of mixed types, cast all as string.
1428                                                  * Logic needs to be consistent with DBA::p() data types.
1429                                                  */
1430                                                 $is_int = false;
1431                                                 $is_alpha = false;
1432                                                 foreach ($value as $single_value) {
1433                                                         if (is_int($single_value)) {
1434                                                                 $is_int = true;
1435                                                         } else {
1436                                                                 $is_alpha = true;
1437                                                         }
1438                                                 }
1439
1440                                                 if ($is_int && $is_alpha) {
1441                                                         foreach ($value as &$ref) {
1442                                                                 if (is_int($ref)) {
1443                                                                         $ref = (string)$ref;
1444                                                                 }
1445                                                         }
1446                                                         unset($ref); //Prevent accidental re-use.
1447                                                 }
1448
1449                                                 $new_values = array_merge($new_values, array_values($value));
1450                                                 $placeholders = substr(str_repeat("?, ", count($value)), 0, -2);
1451                                                 $condition_string .= "`" . $field . "` IN (" . $placeholders . ")";
1452                                         } else {
1453                                                 $new_values[$field] = $value;
1454                                                 $condition_string .= "`" . $field . "` = ?";
1455                                         }
1456                                 }
1457                                 $condition_string = " WHERE (" . $condition_string . ")";
1458                                 $condition = $new_values;
1459                         }
1460                 }
1461
1462                 return $condition_string;
1463         }
1464
1465         /**
1466          * @brief Returns the SQL parameter string built from the provided parameter array
1467          *
1468          * @param array $params
1469          * @return string
1470          */
1471         public static function buildParameter(array $params = [])
1472         {
1473                 $order_string = '';
1474                 if (isset($params['order'])) {
1475                         $order_string = " ORDER BY ";
1476                         foreach ($params['order'] AS $fields => $order) {
1477                                 if (!is_int($fields)) {
1478                                         $order_string .= "`" . $fields . "` " . ($order ? "DESC" : "ASC") . ", ";
1479                                 } else {
1480                                         $order_string .= "`" . $order . "`, ";
1481                                 }
1482                         }
1483                         $order_string = substr($order_string, 0, -2);
1484                 }
1485
1486                 $limit_string = '';
1487                 if (isset($params['limit']) && is_numeric($params['limit'])) {
1488                         $limit_string = " LIMIT " . intval($params['limit']);
1489                 }
1490
1491                 if (isset($params['limit']) && is_array($params['limit'])) {
1492                         $limit_string = " LIMIT " . intval($params['limit'][0]) . ", " . intval($params['limit'][1]);
1493                 }
1494
1495                 return $order_string.$limit_string;
1496         }
1497
1498         /**
1499          * @brief Fills an array with data from a query
1500          *
1501          * @param object $stmt statement object
1502          * @param bool   $do_close
1503          * @return array Data array
1504          */
1505         public static function toArray($stmt, $do_close = true) {
1506                 if (is_bool($stmt)) {
1507                         return $stmt;
1508                 }
1509
1510                 $data = [];
1511                 while ($row = self::fetch($stmt)) {
1512                         $data[] = $row;
1513                 }
1514                 if ($do_close) {
1515                         self::close($stmt);
1516                 }
1517                 return $data;
1518         }
1519
1520         /**
1521          * @brief Returns the error number of the last query
1522          *
1523          * @return string Error number (0 if no error)
1524          */
1525         public static function errorNo() {
1526                 return self::$errorno;
1527         }
1528
1529         /**
1530          * @brief Returns the error message of the last query
1531          *
1532          * @return string Error message ('' if no error)
1533          */
1534         public static function errorMessage() {
1535                 return self::$error;
1536         }
1537
1538         /**
1539          * @brief Closes the current statement
1540          *
1541          * @param object $stmt statement object
1542          * @return boolean was the close successful?
1543          */
1544         public static function close($stmt) {
1545
1546                 $stamp1 = microtime(true);
1547
1548                 if (!is_object($stmt)) {
1549                         return false;
1550                 }
1551
1552                 switch (self::$driver) {
1553                         case 'pdo':
1554                                 $ret = $stmt->closeCursor();
1555                                 break;
1556                         case 'mysqli':
1557                                 // MySQLi offers both a mysqli_stmt and a mysqli_result class.
1558                                 // We should be careful not to assume the object type of $stmt
1559                                 // because DBA::p() has been able to return both types.
1560                                 if ($stmt instanceof mysqli_stmt) {
1561                                         $stmt->free_result();
1562                                         $ret = $stmt->close();
1563                                 } elseif ($stmt instanceof mysqli_result) {
1564                                         $stmt->free();
1565                                         $ret = true;
1566                                 } else {
1567                                         $ret = false;
1568                                 }
1569                                 break;
1570                 }
1571
1572                 self::$profiler->saveTimestamp($stamp1, 'database', System::callstack());
1573
1574                 return $ret;
1575         }
1576
1577         /**
1578          * @brief Return a list of database processes
1579          *
1580          * @return array
1581          *      'list' => List of processes, separated in their different states
1582          *      'amount' => Number of concurrent database processes
1583          * @throws \Exception
1584          */
1585         public static function processlist()
1586         {
1587                 $ret = self::p("SHOW PROCESSLIST");
1588                 $data = self::toArray($ret);
1589
1590                 $processes = 0;
1591                 $states = [];
1592                 foreach ($data as $process) {
1593                         $state = trim($process["State"]);
1594
1595                         // Filter out all non blocking processes
1596                         if (!in_array($state, ["", "init", "statistics", "updating"])) {
1597                                 ++$states[$state];
1598                                 ++$processes;
1599                         }
1600                 }
1601
1602                 $statelist = "";
1603                 foreach ($states as $state => $usage) {
1604                         if ($statelist != "") {
1605                                 $statelist .= ", ";
1606                         }
1607                         $statelist .= $state.": ".$usage;
1608                 }
1609                 return(["list" => $statelist, "amount" => $processes]);
1610         }
1611
1612         /**
1613          * Checks if $array is a filled array with at least one entry.
1614          *
1615          * @param mixed $array A filled array with at least one entry
1616          *
1617          * @return boolean Whether $array is a filled array or an object with rows
1618          */
1619         public static function isResult($array)
1620         {
1621                 // It could be a return value from an update statement
1622                 if (is_bool($array)) {
1623                         return $array;
1624                 }
1625
1626                 if (is_object($array)) {
1627                         return self::numRows($array) > 0;
1628                 }
1629
1630                 return (is_array($array) && (count($array) > 0));
1631         }
1632
1633         /**
1634          * @brief Callback function for "esc_array"
1635          *
1636          * @param mixed   $value         Array value
1637          * @param string  $key           Array key
1638          * @param boolean $add_quotation add quotation marks for string values
1639          * @return void
1640          */
1641         private static function escapeArrayCallback(&$value, $key, $add_quotation)
1642         {
1643                 if (!$add_quotation) {
1644                         if (is_bool($value)) {
1645                                 $value = ($value ? '1' : '0');
1646                         } else {
1647                                 $value = self::escape($value);
1648                         }
1649                         return;
1650                 }
1651
1652                 if (is_bool($value)) {
1653                         $value = ($value ? 'true' : 'false');
1654                 } elseif (is_float($value) || is_integer($value)) {
1655                         $value = (string) $value;
1656                 } else {
1657                         $value = "'" . self::escape($value) . "'";
1658                 }
1659         }
1660
1661         /**
1662          * @brief Escapes a whole array
1663          *
1664          * @param mixed   $arr           Array with values to be escaped
1665          * @param boolean $add_quotation add quotation marks for string values
1666          * @return void
1667          */
1668         public static function escapeArray(&$arr, $add_quotation = false)
1669         {
1670                 array_walk($arr, 'self::escapeArrayCallback', $add_quotation);
1671         }
1672 }