include/dba.php

   1 <?php
   2 require_once("dbm.php");
   3 require_once('include/datetime.php');
   4
   5 /**
   6  * @class MySQL database class
   7  *
   8  * For debugging, insert 'dbg(1);' anywhere in the program flow.
   9  * dbg(0); will turn it off. Logging is performed at LOGGER_DATA level.
  10  * When logging, all binary info is converted to text and html entities are escaped so that
  11  * the debugging stream is safe to view within both terminals and web pages.
  12  *
  13  * This class is for the low level database stuff that does driver specific things.
  14  */
  15
  16 class dba {
  17
  18         private $debug = 0;
  19         private $db;
  20         private $result;
  21         private $driver;
  22         public  $connected = false;
  23         public  $error = false;
  24         private $_server_info = '';
  25         private static $dbo;
  26
  27         function __construct($server, $user, $pass, $db, $install = false) {
  28                 $a = get_app();
  29
  30                 $stamp1 = microtime(true);
  31
  32                 $server = trim($server);
  33                 $user = trim($user);
  34                 $pass = trim($pass);
  35                 $db = trim($db);
  36
  37                 if (!(strlen($server) && strlen($user))) {
  38                         $this->connected = false;
  39                         $this->db = null;
  40                         return;
  41                 }
  42
  43                 if ($install) {
  44                         if (strlen($server) && ($server !== 'localhost') && ($server !== '127.0.0.1')) {
  45                                 if (! dns_get_record($server, DNS_A + DNS_CNAME + DNS_PTR)) {
  46                                         $this->error = sprintf(t('Cannot locate DNS info for database server \'%s\''), $server);
  47                                         $this->connected = false;
  48                                         $this->db = null;
  49                                         return;
  50                                 }
  51                         }
  52                 }
  53
  54                 if (class_exists('\PDO') && in_array('mysql', PDO::getAvailableDrivers())) {
  55                         $this->driver = 'pdo';
  56                         $connect = "mysql:host=".$server.";dbname=".$db;
  57                         if (isset($a->config["system"]["db_charset"])) {
  58                                 $connect .= ";charset=".$a->config["system"]["db_charset"];
  59                         }
  60                         $this->db = @new PDO($connect, $user, $pass);
  61                         if (!$this->db->errorCode()) {
  62                                 $this->connected = true;
  63                         }
  64                 } elseif (class_exists('mysqli')) {
  65                         $this->driver = 'mysqli';
  66                         $this->db = @new mysqli($server,$user,$pass,$db);
  67                         if (!mysqli_connect_errno()) {
  68                                 $this->connected = true;
  69
  70                                 if (isset($a->config["system"]["db_charset"])) {
  71                                         $this->db->set_charset($a->config["system"]["db_charset"]);
  72                                 }
  73                         }
  74                 } elseif (function_exists('mysql_connect')) {
  75                         $this->driver = 'mysql';
  76                         $this->db = mysql_connect($server,$user,$pass);
  77                         if ($this->db && mysql_select_db($db,$this->db)) {
  78                                 $this->connected = true;
  79
  80                                 if (isset($a->config["system"]["db_charset"])) {
  81                                         mysql_set_charset($a->config["system"]["db_charset"], $this->db);
  82                                 }
  83                         }
  84                 } else {
  85                         // No suitable SQL driver was found.
  86                         if (!$install) {
  87                                 system_unavailable();
  88                         }
  89                 }
  90
  91                 if (!$this->connected) {
  92                         $this->db = null;
  93                         if (!$install) {
  94                                 system_unavailable();
  95                         }
  96                 }
  97                 $a->save_timestamp($stamp1, "network");
  98
  99                 self::$dbo = $this;
 100         }
 101
 102         /**
 103          * @brief Returns the MySQL server version string
 104          *
 105          * This function discriminate between the deprecated mysql API and the current
 106          * object-oriented mysqli API. Example of returned string: 5.5.46-0+deb8u1
 107          *
 108          * @return string
 109          */
 110         public function server_info() {
 111                 if ($this->_server_info == '') {
 112                         switch ($this->driver) {
 113                                 case 'pdo':
 114                                         $this->_server_info = $this->db->getAttribute(PDO::ATTR_SERVER_VERSION);
 115                                         break;
 116                                 case 'mysqli':
 117                                         $this->_server_info = $this->db->server_info;
 118                                         break;
 119                                 case 'mysql':
 120                                         $this->_server_info = mysql_get_server_info($this->db);
 121                                         break;
 122                         }
 123                 }
 124                 return $this->_server_info;
 125         }
 126
 127         /**
 128          * @brief Returns the selected database name
 129          *
 130          * @return string
 131          */
 132         public function database_name() {
 133                 $r = $this->q("SELECT DATABASE() AS `db`");
 134
 135                 return $r[0]['db'];
 136         }
 137
 138         /**
 139          * @brief Analyze a database query and log this if some conditions are met.
 140          *
 141          * @param string $query The database query that will be analyzed
 142          */
 143         public function log_index($query) {
 144                 $a = get_app();
 145
 146                 if ($a->config["system"]["db_log_index"] == "") {
 147                         return;
 148                 }
 149
 150                 // Don't explain an explain statement
 151                 if (strtolower(substr($query, 0, 7)) == "explain") {
 152                         return;
 153                 }
 154
 155                 // Only do the explain on "select", "update" and "delete"
 156                 if (!in_array(strtolower(substr($query, 0, 6)), array("select", "update", "delete"))) {
 157                         return;
 158                 }
 159
 160                 $r = $this->q("EXPLAIN ".$query);
 161                 if (!dbm::is_result($r)) {
 162                         return;
 163                 }
 164
 165                 $watchlist = explode(',', $a->config["system"]["db_log_index_watch"]);
 166                 $blacklist = explode(',', $a->config["system"]["db_log_index_blacklist"]);
 167
 168                 foreach ($r AS $row) {
 169                         if ((intval($a->config["system"]["db_loglimit_index"]) > 0)) {
 170                                 $log = (in_array($row['key'], $watchlist) AND
 171                                         ($row['rows'] >= intval($a->config["system"]["db_loglimit_index"])));
 172                         } else {
 173                                 $log = false;
 174                         }
 175
 176                         if ((intval($a->config["system"]["db_loglimit_index_high"]) > 0) AND ($row['rows'] >= intval($a->config["system"]["db_loglimit_index_high"]))) {
 177                                 $log = true;
 178                         }
 179
 180                         if (in_array($row['key'], $blacklist) OR ($row['key'] == "")) {
 181                                 $log = false;
 182                         }
 183
 184                         if ($log) {
 185                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 186                                 @file_put_contents($a->config["system"]["db_log_index"], datetime_convert()."\t".
 187                                                 $row['key']."\t".$row['rows']."\t".$row['Extra']."\t".
 188                                                 basename($backtrace[1]["file"])."\t".
 189                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 190                                                 substr($query, 0, 2000)."\n", FILE_APPEND);
 191                         }
 192                 }
 193         }
 194
 195         public function q($sql, $onlyquery = false) {
 196                 $a = get_app();
 197
 198                 if (!$this->db || !$this->connected) {
 199                         return false;
 200                 }
 201
 202                 $this->error = '';
 203
 204                 $connstr = ($this->connected() ? "Connected" : "Disonnected");
 205
 206                 $stamp1 = microtime(true);
 207
 208                 $orig_sql = $sql;
 209
 210                 if (x($a->config,'system') && x($a->config['system'], 'db_callstack')) {
 211                         $sql = "/*".$a->callstack()." */ ".$sql;
 212                 }
 213
 214                 $columns = 0;
 215
 216                 switch ($this->driver) {
 217                         case 'pdo':
 218                                 $result = @$this->db->query($sql);
 219                                 // Is used to separate between queries that returning data - or not
 220                                 if (!is_bool($result)) {
 221                                         $columns = $result->columnCount();
 222                                 }
 223                                 break;
 224                         case 'mysqli':
 225                                 $result = @$this->db->query($sql);
 226                                 break;
 227                         case 'mysql':
 228                                 $result = @mysql_query($sql,$this->db);
 229                                 break;
 230                 }
 231                 $stamp2 = microtime(true);
 232                 $duration = (float)($stamp2 - $stamp1);
 233
 234                 $a->save_timestamp($stamp1, "database");
 235
 236                 if (strtolower(substr($orig_sql, 0, 6)) != "select") {
 237                         $a->save_timestamp($stamp1, "database_write");
 238                 }
 239                 if (x($a->config,'system') && x($a->config['system'],'db_log')) {
 240                         if (($duration > $a->config["system"]["db_loglimit"])) {
 241                                 $duration = round($duration, 3);
 242                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 243                                 @file_put_contents($a->config["system"]["db_log"], datetime_convert()."\t".$duration."\t".
 244                                                 basename($backtrace[1]["file"])."\t".
 245                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 246                                                 substr($sql, 0, 2000)."\n", FILE_APPEND);
 247                         }
 248                 }
 249
 250                 switch ($this->driver) {
 251                         case 'pdo':
 252                                 $errorInfo = $this->db->errorInfo();
 253                                 if ($errorInfo) {
 254                                         $this->error = $errorInfo[2];
 255                                         $this->errorno = $errorInfo[1];
 256                                 }
 257                                 break;
 258                         case 'mysqli':
 259                                 if ($this->db->errno) {
 260                                         $this->error = $this->db->error;
 261                                         $this->errorno = $this->db->errno;
 262                                 }
 263                                 break;
 264                         case 'mysql':
 265                                 if (mysql_errno($this->db)) {
 266                                         $this->error = mysql_error($this->db);
 267                                         $this->errorno = mysql_errno($this->db);
 268                                 }
 269                                 break;
 270                 }
 271                 if (strlen($this->error)) {
 272                         logger('DB Error ('.$connstr.') '.$this->errorno.': '.$this->error);
 273                 }
 274
 275                 if ($this->debug) {
 276
 277                         $mesg = '';
 278
 279                         if ($result === false) {
 280                                 $mesg = 'false';
 281                         } elseif ($result === true) {
 282                                 $mesg = 'true';
 283                         } else {
 284                                 switch ($this->driver) {
 285                                         case 'pdo':
 286                                                 $mesg = $result->rowCount().' results'.EOL;
 287                                                 break;
 288                                         case 'mysqli':
 289                                                 $mesg = $result->num_rows.' results'.EOL;
 290                                                 break;
 291                                         case 'mysql':
 292                                                 $mesg = mysql_num_rows($result).' results'.EOL;
 293                                                 break;
 294                                 }
 295                         }
 296
 297                         $str =  'SQL = ' . printable($sql) . EOL . 'SQL returned ' . $mesg
 298                                 . (($this->error) ? ' error: ' . $this->error : '')
 299                                 . EOL;
 300
 301                         logger('dba: ' . $str );
 302                 }
 303
 304                 /**
 305                  * If dbfail.out exists, we will write any failed calls directly to it,
 306                  * regardless of any logging that may or may nor be in effect.
 307                  * These usually indicate SQL syntax errors that need to be resolved.
 308                  */
 309
 310                 if ($result === false) {
 311                         logger('dba: ' . printable($sql) . ' returned false.' . "\n" . $this->error);
 312                         if (file_exists('dbfail.out')) {
 313                                 file_put_contents('dbfail.out', datetime_convert() . "\n" . printable($sql) . ' returned false' . "\n" . $this->error . "\n", FILE_APPEND);
 314                         }
 315                 }
 316
 317                 if (is_bool($result)) {
 318                         return $result;
 319                 }
 320                 if ($onlyquery) {
 321                         $this->result = $result;
 322                         return true;
 323                 }
 324
 325                 $r = array();
 326                 switch ($this->driver) {
 327                         case 'pdo':
 328                                 while ($x = $result->fetch(PDO::FETCH_ASSOC)) {
 329                                         $r[] = $x;
 330                                 }
 331                                 $result->closeCursor();
 332                                 break;
 333                         case 'mysqli':
 334                                 while ($x = $result->fetch_array(MYSQLI_ASSOC)) {
 335                                         $r[] = $x;
 336                                 }
 337                                 $result->free_result();
 338                                 break;
 339                         case 'mysql':
 340                                 while ($x = mysql_fetch_array($result, MYSQL_ASSOC)) {
 341                                         $r[] = $x;
 342                                 }
 343                                 mysql_free_result($result);
 344                                 break;
 345                 }
 346
 347                 // PDO doesn't return "true" on successful operations - like mysqli does
 348                 // Emulate this behaviour by checking if the query returned data and had columns
 349                 // This should be reliable enough
 350                 if (($this->driver == 'pdo') AND (count($r) == 0) AND ($columns == 0)) {
 351                         return true;
 352                 }
 353
 354                 //$a->save_timestamp($stamp1, "database");
 355
 356                 if ($this->debug) {
 357                         logger('dba: ' . printable(print_r($r, true)));
 358                 }
 359                 return($r);
 360         }
 361
 362         public function dbg($dbg) {
 363                 $this->debug = $dbg;
 364         }
 365
 366         public function escape($str) {
 367                 if ($this->db && $this->connected) {
 368                         switch ($this->driver) {
 369                                 case 'pdo':
 370                                         return substr(@$this->db->quote($str, PDO::PARAM_STR), 1, -1);
 371                                 case 'mysqli':
 372                                         return @$this->db->real_escape_string($str);
 373                                 case 'mysql':
 374                                         return @mysql_real_escape_string($str,$this->db);
 375                         }
 376                 }
 377         }
 378
 379         function connected() {
 380                 switch ($this->driver) {
 381                         case 'pdo':
 382                                 // Not sure if this really is working like expected
 383                                 $connected = ($this->db->getAttribute(PDO::ATTR_CONNECTION_STATUS) != "");
 384                                 break;
 385                         case 'mysqli':
 386                                 $connected = $this->db->ping();
 387                                 break;
 388                         case 'mysql':
 389                                 $connected = mysql_ping($this->db);
 390                                 break;
 391                 }
 392                 return $connected;
 393         }
 394
 395         function insert_id() {
 396                 switch ($this->driver) {
 397                         case 'pdo':
 398                                 $id = $this->db->lastInsertId();
 399                                 break;
 400                         case 'mysqli':
 401                                 $id = $this->db->insert_id;
 402                                 break;
 403                         case 'mysql':
 404                                 $id = mysql_insert_id($this->db);
 405                                 break;
 406                 }
 407                 return $id;
 408         }
 409
 410         function __destruct() {
 411                 if ($this->db) {
 412                         switch ($this->driver) {
 413                                 case 'pdo':
 414                                         $this->db = null;
 415                                         break;
 416                                 case 'mysqli':
 417                                         $this->db->close();
 418                                         break;
 419                                 case 'mysql':
 420                                         mysql_close($this->db);
 421                                         break;
 422                         }
 423                 }
 424         }
 425
 426         /**
 427          * @brief Replaces ANY_VALUE() function by MIN() function,
 428          *  if the database server does not support ANY_VALUE().
 429          *
 430          * Considerations for Standard SQL, or MySQL with ONLY_FULL_GROUP_BY (default since 5.7.5).
 431          * ANY_VALUE() is available from MySQL 5.7.5 https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html
 432          * A standard fall-back is to use MIN().
 433          *
 434          * @param string $sql An SQL string without the values
 435          * @return string The input SQL string modified if necessary.
 436          */
 437         public function any_value_fallback($sql) {
 438                 $server_info = $this->server_info();
 439                 if (version_compare($server_info, '5.7.5', '<') ||
 440                         (stripos($server_info, 'MariaDB') !== false)) {
 441                         $sql = str_ireplace('ANY_VALUE(', 'MIN(', $sql);
 442                 }
 443                 return $sql;
 444         }
 445
 446         /**
 447          * @brief Replaces the ? placeholders with the parameters in the $args array
 448          *
 449          * @param string $sql SQL query
 450          * @param array $args The parameters that are to replace the ? placeholders
 451          * @return string The replaced SQL query
 452          */
 453         static private function replace_parameters($sql, $args) {
 454                 $offset = 0;
 455                 foreach ($args AS $param => $value) {
 456                         if (is_int($args[$param]) OR is_float($args[$param])) {
 457                                 $replace = intval($args[$param]);
 458                         } else {
 459                                 $replace = "'".dbesc($args[$param])."'";
 460                         }
 461
 462                         $pos = strpos($sql, '?', $offset);
 463                         if ($pos !== false) {
 464                                 $sql = substr_replace($sql, $replace, $pos, 1);
 465                         }
 466                         $offset = $pos + strlen($replace);
 467                 }
 468                 return $sql;
 469         }
 470
 471         /**
 472          * @brief Executes a prepared statement that returns data
 473          * @usage Example: $r = p("SELECT * FROM `item` WHERE `guid` = ?", $guid);
 474          * @param string $sql SQL statement
 475          * @return object statement object
 476          */
 477         static public function p($sql) {
 478                 $a = get_app();
 479
 480                 $stamp1 = microtime(true);
 481
 482                 $args = func_get_args();
 483                 unset($args[0]);
 484
 485                 if (!self::$dbo OR !self::$dbo->connected) {
 486                         return false;
 487                 }
 488
 489                 $sql = self::$dbo->any_value_fallback($sql);
 490
 491                 if (x($a->config,'system') && x($a->config['system'], 'db_callstack')) {
 492                         $sql = "/*".$a->callstack()." */ ".$sql;
 493                 }
 494
 495                 switch (self::$dbo->driver) {
 496                         case 'pdo':
 497                                 if (!$stmt = self::$dbo->db->prepare($sql)) {
 498                                         $errorInfo = self::$dbo->db->errorInfo();
 499                                         self::$dbo->error = $errorInfo[2];
 500                                         self::$dbo->errorno = $errorInfo[1];
 501                                         $retval = false;
 502                                         break;
 503                                 }
 504
 505                                 foreach ($args AS $param => $value) {
 506                                         $stmt->bindParam($param, $args[$param]);
 507                                 }
 508
 509                                 if (!$stmt->execute()) {
 510                                         $errorInfo = self::$dbo->db->errorInfo();
 511                                         self::$dbo->error = $errorInfo[2];
 512                                         self::$dbo->errorno = $errorInfo[1];
 513                                         $retval = false;
 514                                 } else {
 515                                         $retval = $stmt;
 516                                 }
 517                                 break;
 518                         case 'mysqli':
 519                                 $stmt = self::$dbo->db->stmt_init();
 520
 521                                 if (!$stmt->prepare($sql)) {
 522                                         self::$dbo->error = self::$dbo->db->error;
 523                                         self::$dbo->errorno = self::$dbo->db->errno;
 524                                         $retval = false;
 525                                         break;
 526                                 }
 527
 528                                 $params = '';
 529                                 $values = array();
 530                                 foreach ($args AS $param => $value) {
 531                                         if (is_int($args[$param])) {
 532                                                 $params .= 'i';
 533                                         } elseif (is_float($args[$param])) {
 534                                                 $params .= 'd';
 535                                         } elseif (is_string($args[$param])) {
 536                                                 $params .= 's';
 537                                         } else {
 538                                                 $params .= 'b';
 539                                         }
 540                                         $values[] = &$args[$param];
 541                                 }
 542
 543                                 array_unshift($values, $params);
 544
 545                                 call_user_func_array(array($stmt, 'bind_param'), $values);
 546
 547                                 if (!$stmt->execute()) {
 548                                         self::$dbo->error = self::$dbo->db->error;
 549                                         self::$dbo->errorno = self::$dbo->db->errno;
 550                                         $retval = false;
 551                                 } else {
 552                                         $stmt->store_result();
 553                                         $retval = $stmt;
 554                                 }
 555                                 break;
 556                         case 'mysql':
 557                                 // For the old "mysql" functions we cannot use prepared statements
 558                                 $retval = mysql_query(self::replace_parameters($sql, $args), self::$dbo->db);
 559                                 if (mysql_errno(self::$dbo->db)) {
 560                                         self::$dbo->error = mysql_error(self::$dbo->db);
 561                                         self::$dbo->errorno = mysql_errno(self::$dbo->db);
 562                                 }
 563                                 break;
 564                 }
 565
 566                 $a->save_timestamp($stamp1, 'database');
 567
 568                 if (x($a->config,'system') && x($a->config['system'], 'db_log')) {
 569
 570                         $stamp2 = microtime(true);
 571                         $duration = (float)($stamp2 - $stamp1);
 572
 573                         if (($duration > $a->config["system"]["db_loglimit"])) {
 574                                 $duration = round($duration, 3);
 575                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 576
 577                                 @file_put_contents($a->config["system"]["db_log"], datetime_convert()."\t".$duration."\t".
 578                                                 basename($backtrace[1]["file"])."\t".
 579                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 580                                                 substr(self::replace_parameters($sql, $args), 0, 2000)."\n", FILE_APPEND);
 581                         }
 582                 }
 583                 return $retval;
 584         }
 585
 586         /**
 587          * @brief Executes a prepared statement like UPDATE or INSERT that doesn't return data
 588          *
 589          * @param string $sql SQL statement
 590          * @return boolean Was the query successfull? False is returned only if an error occurred
 591          */
 592         static public function e($sql) {
 593                 $a = get_app();
 594
 595                 $stamp = microtime(true);
 596
 597                 $args = func_get_args();
 598
 599                 $stmt = call_user_func_array('self::p', $args);
 600
 601                 if (is_bool($stmt)) {
 602                         $retval = $stmt;
 603                 } elseif (is_object($stmt)) {
 604                         $retval = true;
 605                 } else {
 606                         $retval = false;
 607                 }
 608
 609                 self::close($stmt);
 610
 611                 $a->save_timestamp($stamp, "database_write");
 612
 613                 return $retval;
 614         }
 615
 616         /**
 617          * @brief Check if data exists
 618          *
 619          * @param string $sql SQL statement
 620          * @return boolean Are there rows for that query?
 621          */
 622         static public function exists($sql) {
 623                 $args = func_get_args();
 624
 625                 $stmt = call_user_func_array('self::p', $args);
 626
 627                 if (is_bool($stmt)) {
 628                         $retval = $stmt;
 629                 } else {
 630                         $retval = (self::rows($stmt) > 0);
 631                 }
 632
 633                 self::close($stmt);
 634
 635                 return $retval;
 636         }
 637
 638         /**
 639          * @brief Returns the number of rows of a statement
 640          *
 641          * @param object Statement object
 642          * @return int Number of rows
 643          */
 644         static public function num_rows($stmt) {
 645                 switch (self::$dbo->driver) {
 646                         case 'pdo':
 647                                 return $stmt->rowCount();
 648                         case 'mysqli':
 649                                 return $stmt->num_rows;
 650                         case 'mysql':
 651                                 return mysql_num_rows($stmt);
 652                 }
 653                 return 0;
 654         }
 655
 656         /**
 657          * @brief Fetch a single row
 658          *
 659          * @param object $stmt statement object
 660          * @return array current row
 661          */
 662         static public function fetch($stmt) {
 663                 if (!is_object($stmt)) {
 664                         return false;
 665                 }
 666
 667                 switch (self::$dbo->driver) {
 668                         case 'pdo':
 669                                 return $stmt->fetch(PDO::FETCH_ASSOC);
 670                         case 'mysqli':
 671                                 // This code works, but is slow
 672
 673                                 // Bind the result to a result array
 674                                 $cols = array();
 675
 676                                 $cols_num = array();
 677                                 for ($x = 0; $x < $stmt->field_count; $x++) {
 678                                         $cols[] = &$cols_num[$x];
 679                                 }
 680
 681                                 call_user_func_array(array($stmt, 'bind_result'), $cols);
 682
 683                                 if (!$stmt->fetch()) {
 684                                         return false;
 685                                 }
 686
 687                                 // The slow part:
 688                                 // We need to get the field names for the array keys
 689                                 // It seems that there is no better way to do this.
 690                                 $result = $stmt->result_metadata();
 691                                 $fields = $result->fetch_fields();
 692
 693                                 $columns = array();
 694                                 foreach ($cols_num AS $param => $col) {
 695                                         $columns[$fields[$param]->name] = $col;
 696                                 }
 697                                 return $columns;
 698                         case 'mysql':
 699                                 return mysql_fetch_array(self::$dbo->result, MYSQL_ASSOC);
 700                 }
 701         }
 702
 703         /**
 704          * @brief Closes the current statement
 705          *
 706          * @param object $stmt statement object
 707          * @return boolean was the close successfull?
 708          */
 709         static public function close($stmt) {
 710                 if (!is_object($stmt)) {
 711                         return false;
 712                 }
 713
 714                 switch (self::$dbo->driver) {
 715                         case 'pdo':
 716                                 return $stmt->closeCursor();
 717                         case 'mysqli':
 718                                 return $stmt->free_result();
 719                                 return $stmt->close();
 720                         case 'mysql':
 721                                 return mysql_free_result($stmt);
 722                 }
 723         }
 724 }
 725
 726 function printable($s) {
 727         $s = preg_replace("~([\x01-\x08\x0E-\x0F\x10-\x1F\x7F-\xFF])~",".", $s);
 728         $s = str_replace("\x00",'.',$s);
 729         if (x($_SERVER,'SERVER_NAME')) {
 730                 $s = escape_tags($s);
 731         }
 732         return $s;
 733 }
 734
 735 // Procedural functions
 736 function dbg($state) {
 737         global $db;
 738
 739         if ($db) {
 740                 $db->dbg($state);
 741         }
 742 }
 743
 744 function dbesc($str) {
 745         global $db;
 746
 747         if ($db && $db->connected) {
 748                 return($db->escape($str));
 749         } else {
 750                 return(str_replace("'","\\'",$str));
 751         }
 752 }
 753
 754 // Function: q($sql,$args);
 755 // Description: execute SQL query with printf style args.
 756 // Example: $r = q("SELECT * FROM `%s` WHERE `uid` = %d",
 757 //                   'user', 1);
 758 function q($sql) {
 759         global $db;
 760         $args = func_get_args();
 761         unset($args[0]);
 762
 763         if ($db && $db->connected) {
 764                 $sql = $db->any_value_fallback($sql);
 765                 $stmt = @vsprintf($sql,$args); // Disabled warnings
 766                 //logger("dba: q: $stmt", LOGGER_ALL);
 767                 if ($stmt === false)
 768                         logger('dba: vsprintf error: ' . print_r(debug_backtrace(),true), LOGGER_DEBUG);
 769
 770                 $db->log_index($stmt);
 771
 772                 return $db->q($stmt);
 773         }
 774
 775         /**
 776          *
 777          * This will happen occasionally trying to store the
 778          * session data after abnormal program termination
 779          *
 780          */
 781         logger('dba: no database: ' . print_r($args,true));
 782         return false;
 783 }
 784
 785 /**
 786  * @brief Performs a query with "dirty reads"
 787  *
 788  * By doing dirty reads (reading uncommitted data) no locks are performed
 789  * This function can be used to fetch data that doesn't need to be reliable.
 790  *
 791  * @param $args Query parameters (1 to N parameters of different types)
 792  * @return array Query array
 793  */
 794 function qu($sql) {
 795         global $db;
 796
 797         $args = func_get_args();
 798         unset($args[0]);
 799
 800         if ($db && $db->connected) {
 801                 $sql = $db->any_value_fallback($sql);
 802                 $stmt = @vsprintf($sql,$args); // Disabled warnings
 803                 if ($stmt === false)
 804                         logger('dba: vsprintf error: ' . print_r(debug_backtrace(),true), LOGGER_DEBUG);
 805
 806                 $db->log_index($stmt);
 807
 808                 $db->q("SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;");
 809                 $retval = $db->q($stmt);
 810                 $db->q("SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;");
 811                 return $retval;
 812         }
 813
 814         /**
 815          *
 816          * This will happen occasionally trying to store the
 817          * session data after abnormal program termination
 818          *
 819          */
 820         logger('dba: no database: ' . print_r($args,true));
 821         return false;
 822 }
 823
 824 /**
 825  *
 826  * Raw db query, no arguments
 827  *
 828  */
 829 function dbq($sql) {
 830         global $db;
 831
 832         if ($db && $db->connected) {
 833                 $ret = $db->q($sql);
 834         } else {
 835                 $ret = false;
 836         }
 837         return $ret;
 838 }
 839
 840 // Caller is responsible for ensuring that any integer arguments to
 841 // dbesc_array are actually integers and not malformed strings containing
 842 // SQL injection vectors. All integer array elements should be specifically
 843 // cast to int to avoid trouble.
 844 function dbesc_array_cb(&$item, $key) {
 845         if (is_string($item))
 846                 $item = dbesc($item);
 847 }
 848
 849 function dbesc_array(&$arr) {
 850         if (is_array($arr) && count($arr)) {
 851                 array_walk($arr,'dbesc_array_cb');
 852         }
 853 }
 854
 855 function dba_timer() {
 856         return microtime(true);
 857 }