functions/strings.php

   1 <?php
   2
   3 /**
   4  * strings.php
   5  *
   6  * This code provides various string manipulation functions that are
   7  * used by the rest of the SquirrelMail code.
   8  *
   9  * @copyright &copy; 1999-2006 The SquirrelMail Project Team
  10  * @license http://opensource.org/licenses/gpl-license.php GNU Public License
  11  * @version $Id$
  12  * @package squirrelmail
  13  */
  14
  15 /**
  16  * Appends citation markers to the string.
  17  * Also appends a trailing space.
  18  *
  19  * @author Justus Pendleton
  20  * @param string $str The string to append to
  21  * @param int $citeLevel the number of markers to append
  22  * @return null
  23  * @since 1.5.1
  24  */
  25 function sqMakeCite (&$str, $citeLevel) {
  26     for ($i = 0; $i < $citeLevel; $i++) {
  27         $str .= '>';
  28     }
  29     if ($citeLevel != 0) {
  30         $str .= ' ';
  31     }
  32 }
  33
  34 /**
  35  * Create a newline in the string, adding citation
  36  * markers to the newline as necessary.
  37  *
  38  * @author Justus Pendleton
  39  * @param string $str the string to make a newline in
  40  * @param int $citeLevel the citation level the newline is at
  41  * @param int $column starting column of the newline
  42  * @return null
  43  * @since 1.5.1
  44  */
  45 function sqMakeNewLine (&$str, $citeLevel, &$column) {
  46     $str .= "\n";
  47     $column = 0;
  48     if ($citeLevel > 0) {
  49         sqMakeCite ($str, $citeLevel);
  50         $column = $citeLevel + 1;
  51     } else {
  52         $column = 0;
  53     }
  54 }
  55
  56 /**
  57  * Checks for spaces in strings - only used if PHP doesn't have native ctype support
  58  *
  59  * You might be able to rewrite the function by adding short evaluation form.
  60  *
  61  * possible problems:
  62  *  - iso-2022-xx charsets  - hex 20 might be part of other symbol. I might
  63  * be wrong. 0x20 is not used in iso-2022-jp. I haven't checked iso-2022-kr
  64  * and iso-2022-cn mappings.
  65  *
  66  *  - no-break space (&nbsp;) - it is 8bit symbol, that depends on charset.
  67  * there are at least three different charset groups that have nbsp in
  68  * different places.
  69  *
  70  * I don't see any charset/nbsp options in php ctype either.
  71  *
  72  * @param string $string tested string
  73  * @return bool true when only whitespace symbols are present in test string
  74  * @since 1.5.1
  75  */
  76 function sm_ctype_space($string) {
  77     if ( preg_match('/^[\x09-\x0D]|^\x20/', $string) || $string=='') {
  78         return true;
  79     } else {
  80         return false;
  81     }
  82 }
  83
  84 /**
  85  * Wraps text at $wrap characters.  While sqWordWrap takes
  86  * a single line of text and wraps it, this function works
  87  * on the entire corpus at once, this allows it to be a little
  88  * bit smarter and when and how to wrap.
  89  *
  90  * @author Justus Pendleton
  91  * @param string $body the entire body of text
  92  * @param int $wrap the maximum line length
  93  * @return string the wrapped text
  94  * @since 1.5.1
  95  */
  96 function &sqBodyWrap (&$body, $wrap) {
  97     //check for ctype support, and fake it if it doesn't exist
  98     if (!function_exists('ctype_space')) {
  99         function ctype_space ($string) {
 100             return sm_ctype_space($string);
 101         }
 102     }
 103
 104     // the newly wrapped text
 105     $outString = '';
 106     // current column since the last newline in the outstring
 107     $outStringCol = 0;
 108     $length = sq_strlen($body);
 109     // where we are in the original string
 110     $pos = 0;
 111     // the number of >>> citation markers we are currently at
 112     $citeLevel = 0;
 113
 114     // the main loop, whenever we start a newline of input text
 115     // we start from here
 116     while ($pos < $length) {
 117        // we're at the beginning of a line, get the new cite level
 118        $newCiteLevel = 0;
 119
 120        while (($pos < $length) && (sq_substr($body,$pos,1) == '>')) {
 121            $newCiteLevel++;
 122            $pos++;
 123
 124            // skip over any spaces interleaved among the cite markers
 125            while (($pos < $length) && (sq_substr($body,$pos,1) == ' ')) {
 126
 127                $pos++;
 128
 129            }
 130            if ($pos >= $length) {
 131                break;
 132            }
 133        }
 134
 135        // special case: if this is a blank line then maintain it
 136        // (i.e. try to preserve original paragraph breaks)
 137        // unless they occur at the very beginning of the text
 138        if ((sq_substr($body,$pos,1) == "\n" ) && (sq_strlen($outString) != 0)) {
 139            $outStringLast = $outString{sq_strlen($outString) - 1};
 140            if ($outStringLast != "\n") {
 141                $outString .= "\n";
 142            }
 143            sqMakeCite ($outString, $newCiteLevel);
 144            $outString .= "\n";
 145            $pos++;
 146            $outStringCol = 0;
 147            continue;
 148        }
 149
 150        // if the cite level has changed, then start a new line
 151        // with the new cite level.
 152        if (($citeLevel != $newCiteLevel) && ($pos > ($newCiteLevel + 1)) && ($outStringCol != 0)) {
 153            sqMakeNewLine ($outString, 0, $outStringCol);
 154        }
 155
 156        $citeLevel = $newCiteLevel;
 157
 158        // prepend the quote level if necessary
 159        if ($outStringCol == 0) {
 160            sqMakeCite ($outString, $citeLevel);
 161            // if we added a citation then move the column
 162            // out by citelevel + 1 (the cite markers + the space)
 163            $outStringCol = $citeLevel + ($citeLevel ? 1 : 0);
 164        } else if ($outStringCol > $citeLevel) {
 165            // not a cite and we're not at the beginning of a line
 166            // in the output.  add a space to separate the new text
 167            // from previous text.
 168            $outString .= ' ';
 169            $outStringCol++;
 170        }
 171
 172        // find the next newline -- we don't want to go further than that
 173        $nextNewline = sq_strpos ($body, "\n", $pos);
 174        if ($nextNewline === FALSE) {
 175            $nextNewline = $length;
 176        }
 177
 178        // Don't wrap unquoted lines at all.  For now the textarea
 179        // will work fine for this.  Maybe revisit this later though
 180        // (for completeness more than anything else, I think)
 181        if ($citeLevel == 0) {
 182            $outString .= sq_substr ($body, $pos, ($nextNewline - $pos));
 183            $outStringCol = $nextNewline - $pos;
 184            if ($nextNewline != $length) {
 185                sqMakeNewLine ($outString, 0, $outStringCol);
 186            }
 187            $pos = $nextNewline + 1;
 188            continue;
 189        }
 190        /**
 191         * Set this to false to stop appending short strings to previous lines
 192         */
 193        $smartwrap = true;
 194        // inner loop, (obviously) handles wrapping up to
 195        // the next newline
 196        while ($pos < $nextNewline) {
 197            // skip over initial spaces
 198            while (($pos < $nextNewline) && (ctype_space (sq_substr($body,$pos,1)))) {
 199                $pos++;
 200            }
 201            // if this is a short line then just append it and continue outer loop
 202            if (($outStringCol + $nextNewline - $pos) <= ($wrap - $citeLevel - 1) ) {
 203                // if this is the final line in the input string then include
 204                // any trailing newlines
 205                //      echo substr($body,$pos,$wrap). "<br />";
 206                if (($nextNewline + 1 == $length) && (sq_substr($body,$nextNewline,1) == "\n")) {
 207                    $nextNewline++;
 208                }
 209
 210                // trim trailing spaces
 211                $lastRealChar = $nextNewline;
 212                while (($lastRealChar > $pos && $lastRealChar < $length) && (ctype_space (sq_substr($body,$lastRealChar,1)))) {
 213                    $lastRealChar--;
 214                }
 215                // decide if appending the short string is what we want
 216                if (($nextNewline < $length && sq_substr($body,$nextNewline,1) == "\n") &&
 217                      isset($lastRealChar)) {
 218                    $mypos = $pos;
 219                    //check the first word:
 220                    while (($mypos < $length) && (sq_substr($body,$mypos,1) == '>')) {
 221                        $mypos++;
 222                        // skip over any spaces interleaved among the cite markers
 223                        while (($mypos < $length) && (sq_substr($body,$mypos,1) == ' ')) {
 224                            $mypos++;
 225                        }
 226                    }
 227 /*
 228                      $ldnspacecnt = 0;
 229                      if ($mypos == $nextNewline+1) {
 230                         while (($mypos < $length) && ($body{$mypos} == ' ')) {
 231                          $ldnspacecnt++;
 232                         }
 233                      }
 234 */
 235
 236                    $firstword = sq_substr($body,$mypos,sq_strpos($body,' ',$mypos) - $mypos);
 237                    //if ($dowrap || $ldnspacecnt > 1 || ($firstword && (
 238                    if (!$smartwrap || $firstword && (
 239                                         $firstword{0} == '-' ||
 240                                         $firstword{0} == '+' ||
 241                                         $firstword{0} == '*' ||
 242                                         sq_substr($firstword,0,1) == sq_strtoupper(sq_substr($firstword,0,1)) ||
 243                                         strpos($firstword,':'))) {
 244                         $outString .= sq_substr($body,$pos,($lastRealChar - $pos+1));
 245                         $outStringCol += ($lastRealChar - $pos);
 246                         sqMakeNewLine($outString,$citeLevel,$outStringCol);
 247                         $nextNewline++;
 248                         $pos = $nextNewline;
 249                         $outStringCol--;
 250                         continue;
 251                    }
 252
 253                }
 254
 255                $outString .= sq_substr ($body, $pos, ($lastRealChar - $pos + 1));
 256                $outStringCol += ($lastRealChar - $pos);
 257                $pos = $nextNewline + 1;
 258                continue;
 259            }
 260
 261            $eol = $pos + $wrap - $citeLevel - $outStringCol;
 262            // eol is the tentative end of line.
 263            // look backwards for there for a whitespace to break at.
 264            // if it's already less than our current position then
 265            // our current line is already too long, break immediately
 266            // and restart outer loop
 267            if ($eol <= $pos) {
 268                sqMakeNewLine ($outString, $citeLevel, $outStringCol);
 269                continue;
 270            }
 271
 272            // start looking backwards for whitespace to break at.
 273            $breakPoint = $eol;
 274            while (($breakPoint > $pos) && (! ctype_space (sq_substr($body,$breakPoint,1)))) {
 275                $breakPoint--;
 276            }
 277
 278            // if we didn't find a breakpoint by looking backward then we
 279            // need to figure out what to do about that
 280            if ($breakPoint == $pos) {
 281                // if we are not at the beginning then end this line
 282                // and start a new loop
 283                if ($outStringCol > ($citeLevel + 1)) {
 284                    sqMakeNewLine ($outString, $citeLevel, $outStringCol);
 285                    continue;
 286                } else {
 287                    // just hard break here.  most likely we are breaking
 288                    // a really long URL.  could also try searching
 289                    // forward for a break point, which is what Mozilla
 290                    // does.  don't bother for now.
 291                    $breakPoint = $eol;
 292                }
 293            }
 294
 295            // special case: maybe we should have wrapped last
 296            // time.  if the first breakpoint here makes the
 297            // current line too long and there is already text on
 298            // the current line, break and loop again if at
 299            // beginning of current line, don't force break
 300            $SLOP = 6;
 301            if ((($outStringCol + ($breakPoint - $pos)) > ($wrap + $SLOP)) && ($outStringCol > ($citeLevel + 1))) {
 302                sqMakeNewLine ($outString, $citeLevel, $outStringCol);
 303                continue;
 304            }
 305
 306            // skip newlines or whitespace at the beginning of the string
 307            $substring = sq_substr ($body, $pos, ($breakPoint - $pos));
 308            $substring = rtrim ($substring); // do rtrim and ctype_space have the same ideas about whitespace?
 309            $outString .= $substring;
 310            $outStringCol += sq_strlen ($substring);
 311            // advance past the whitespace which caused the wrap
 312            $pos = $breakPoint;
 313            while (($pos < $length) && (ctype_space (sq_substr($body,$pos,1)))) {
 314                $pos++;
 315            }
 316            if ($pos < $length) {
 317                sqMakeNewLine ($outString, $citeLevel, $outStringCol);
 318            }
 319        }
 320     }
 321
 322     return $outString;
 323 }
 324
 325 /**
 326  * Wraps text at $wrap characters
 327  *
 328  * Has a problem with special HTML characters, so call this before
 329  * you do character translation.
 330  *
 331  * Specifically, &amp;#039; comes up as 5 characters instead of 1.
 332  * This should not add newlines to the end of lines.
 333  *
 334  * @param string $line the line of text to wrap, by ref
 335  * @param int $wrap the maximum line lenth
 336  * @param string $charset name of charset used in $line string. Available since v.1.5.1.
 337  * @return void
 338  * @since 1.0
 339  */
 340 function sqWordWrap(&$line, $wrap, $charset='') {
 341     global $languages, $squirrelmail_language;
 342
 343     // Use custom wrapping function, if translation provides it
 344     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 345         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_wordwrap')) {
 346         if (mb_detect_encoding($line) != 'ASCII') {
 347             $line = call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_wordwrap', $line, $wrap);
 348             return;
 349         }
 350     }
 351
 352     ereg("^([\t >]*)([^\t >].*)?$", $line, $regs);
 353     $beginning_spaces = $regs[1];
 354     if (isset($regs[2])) {
 355         $words = explode(' ', $regs[2]);
 356     } else {
 357         $words = '';
 358     }
 359
 360     $i = 0;
 361     $line = $beginning_spaces;
 362
 363     while ($i < count($words)) {
 364         /* Force one word to be on a line (minimum) */
 365         $line .= $words[$i];
 366         $line_len = strlen($beginning_spaces) + sq_strlen($words[$i],$charset) + 2;
 367         if (isset($words[$i + 1]))
 368             $line_len += sq_strlen($words[$i + 1],$charset);
 369         $i ++;
 370
 371         /* Add more words (as long as they fit) */
 372         while ($line_len < $wrap && $i < count($words)) {
 373             $line .= ' ' . $words[$i];
 374             $i++;
 375             if (isset($words[$i]))
 376                 $line_len += sq_strlen($words[$i],$charset) + 1;
 377             else
 378                 $line_len += 1;
 379         }
 380
 381         /* Skip spaces if they are the first thing on a continued line */
 382         while (!isset($words[$i]) && $i < count($words)) {
 383             $i ++;
 384         }
 385
 386         /* Go to the next line if we have more to process */
 387         if ($i < count($words)) {
 388             $line .= "\n";
 389         }
 390     }
 391 }
 392
 393 /**
 394  * Does the opposite of sqWordWrap()
 395  * @param string $body the text to un-wordwrap
 396  * @return void
 397  * @since 1.0
 398  */
 399 function sqUnWordWrap(&$body) {
 400     global $squirrelmail_language;
 401
 402     if ($squirrelmail_language == 'ja_JP') {
 403         return;
 404     }
 405
 406     $lines = explode("\n", $body);
 407     $body = '';
 408     $PreviousSpaces = '';
 409     $cnt = count($lines);
 410     for ($i = 0; $i < $cnt; $i ++) {
 411         preg_match("/^([\t >]*)([^\t >].*)?$/", $lines[$i], $regs);
 412         $CurrentSpaces = $regs[1];
 413         if (isset($regs[2])) {
 414             $CurrentRest = $regs[2];
 415         } else {
 416             $CurrentRest = '';
 417         }
 418
 419         if ($i == 0) {
 420             $PreviousSpaces = $CurrentSpaces;
 421             $body = $lines[$i];
 422         } else if (($PreviousSpaces == $CurrentSpaces) /* Do the beginnings match */
 423                    && (strlen($lines[$i - 1]) > 65)    /* Over 65 characters long */
 424                    && strlen($CurrentRest)) {          /* and there's a line to continue with */
 425             $body .= ' ' . $CurrentRest;
 426         } else {
 427             $body .= "\n" . $lines[$i];
 428             $PreviousSpaces = $CurrentSpaces;
 429         }
 430     }
 431     $body .= "\n";
 432 }
 433
 434 /**
 435  * If $haystack is a full mailbox name and $needle is the mailbox
 436  * separator character, returns the last part of the mailbox name.
 437  *
 438  * @param string haystack full mailbox name to search
 439  * @param string needle the mailbox separator character
 440  * @return string the last part of the mailbox name
 441  * @since 1.0
 442  */
 443 function readShortMailboxName($haystack, $needle) {
 444
 445     if ($needle == '') {
 446         $elem = $haystack;
 447     } else {
 448         $parts = explode($needle, $haystack);
 449         $elem = array_pop($parts);
 450         while ($elem == '' && count($parts)) {
 451             $elem = array_pop($parts);
 452         }
 453     }
 454     return( $elem );
 455 }
 456
 457
 458 /**
 459  * get_location
 460  *
 461  * Determines the location to forward to, relative to your server.
 462  * This is used in HTTP Location: redirects.
 463  *
 464  * If set, it uses $config_location_base as the first part of the URL,
 465  * specifically, the protocol, hostname and port parts. The path is
 466  * always autodetected.
 467  *
 468  * @return string the base url for this SquirrelMail installation
 469  * @since 1.0
 470  */
 471 function get_location () {
 472
 473     global $imap_server_type, $config_location_base;
 474
 475     /* Get the path, handle virtual directories */
 476     if(strpos(php_self(), '?')) {
 477         $path = substr(php_self(), 0, strpos(php_self(), '?'));
 478     } else {
 479         $path = php_self();
 480     }
 481     $path = substr($path, 0, strrpos($path, '/'));
 482
 483     // proto+host+port are already set in config:
 484     if ( !empty($config_location_base) ) {
 485         return $config_location_base . $path ;
 486     }
 487     // we computed it before, get it from the session:
 488     if ( sqgetGlobalVar('sq_base_url', $full_url, SQ_SESSION) ) {
 489       return $full_url . $path;
 490     }
 491     // else: autodetect
 492
 493     /* Check if this is a HTTPS or regular HTTP request. */
 494     $proto = 'http://';
 495
 496     /*
 497      * If you have 'SSLOptions +StdEnvVars' in your apache config
 498      *     OR if you have HTTPS=on in your HTTP_SERVER_VARS
 499      *     OR if you are on port 443
 500      */
 501     $getEnvVar = getenv('HTTPS');
 502     if ((isset($getEnvVar) && strcasecmp($getEnvVar, 'on') === 0) ||
 503         (sqgetGlobalVar('HTTPS', $https_on, SQ_SERVER) && strcasecmp($https_on, 'on') === 0) ||
 504         (sqgetGlobalVar('SERVER_PORT', $server_port, SQ_SERVER) &&  $server_port == 443)) {
 505         $proto = 'https://';
 506     }
 507
 508     /* Get the hostname from the Host header or server config. */
 509     if ( !sqgetGlobalVar('HTTP_X_FORWARDED_HOST', $host, SQ_SERVER) || empty($host) ) {
 510         if ( !sqgetGlobalVar('HTTP_HOST', $host, SQ_SERVER) || empty($host) ) {
 511             if ( !sqgetGlobalVar('SERVER_NAME', $host, SQ_SERVER) || empty($host) ) {
 512                 $host = '';
 513             }
 514         }
 515     }
 516
 517     $port = '';
 518     if (! strstr($host, ':')) {
 519         if (sqgetGlobalVar('SERVER_PORT', $server_port, SQ_SERVER)) {
 520             if (($server_port != 80 && $proto == 'http://') ||
 521                 ($server_port != 443 && $proto == 'https://')) {
 522                 $port = sprintf(':%d', $server_port);
 523             }
 524         }
 525     }
 526
 527     /* this is a workaround for the weird macosx caching that
 528      * causes Apache to return 16080 as the port number, which causes
 529      * SM to bail */
 530
 531     if ($imap_server_type == 'macosx' && $port == ':16080') {
 532         $port = '';
 533     }
 534
 535     /* Fallback is to omit the server name and use a relative */
 536     /* URI, although this is not RFC 2616 compliant.          */
 537     $full_url = ($host ? $proto . $host . $port : '');
 538     sqsession_register($full_url, 'sq_base_url');
 539     return $full_url . $path;
 540 }
 541
 542
 543 /**
 544  * Encrypts password
 545  *
 546  * These functions are used to encrypt the password before it is
 547  * stored in a cookie. The encryption key is generated by
 548  * OneTimePadCreate();
 549  *
 550  * @param string $string the (password)string to encrypt
 551  * @param string $epad the encryption key
 552  * @return string the base64-encoded encrypted password
 553  * @since 1.0
 554  */
 555 function OneTimePadEncrypt ($string, $epad) {
 556     $pad = base64_decode($epad);
 557
 558     if (strlen($pad)>0) {
 559         // make sure that pad is longer than string
 560         while (strlen($string)>strlen($pad)) {
 561             $pad.=$pad;
 562         }
 563     } else {
 564         // FIXME: what should we do when $epad is not base64 encoded or empty.
 565     }
 566
 567     $encrypted = '';
 568     for ($i = 0; $i < strlen ($string); $i++) {
 569         $encrypted .= chr (ord($string[$i]) ^ ord($pad[$i]));
 570     }
 571
 572     return base64_encode($encrypted);
 573 }
 574
 575 /**
 576  * Decrypts a password from the cookie
 577  *
 578  * Decrypts a password from the cookie, encrypted by OneTimePadEncrypt.
 579  * This uses the encryption key that is stored in the session.
 580  *
 581  * @param string $string the string to decrypt
 582  * @param string $epad the encryption key from the session
 583  * @return string the decrypted password
 584  * @since 1.0
 585  */
 586 function OneTimePadDecrypt ($string, $epad) {
 587     $pad = base64_decode($epad);
 588
 589     if (strlen($pad)>0) {
 590         // make sure that pad is longer than string
 591         while (strlen($string)>strlen($pad)) {
 592             $pad.=$pad;
 593         }
 594     } else {
 595         // FIXME: what should we do when $epad is not base64 encoded or empty.
 596     }
 597
 598     $encrypted = base64_decode ($string);
 599     $decrypted = '';
 600     for ($i = 0; $i < strlen ($encrypted); $i++) {
 601         $decrypted .= chr (ord($encrypted[$i]) ^ ord($pad[$i]));
 602     }
 603
 604     return $decrypted;
 605 }
 606
 607
 608 /**
 609  * Randomizes the mt_rand() function.
 610  *
 611  * Toss this in strings or integers and it will seed the generator
 612  * appropriately. With strings, it is better to get them long.
 613  * Use md5() to lengthen smaller strings.
 614  *
 615  * @param mixed $val a value to seed the random number generator. mixed = integer or string.
 616  * @return void
 617  * @since 1.0
 618  */
 619 function sq_mt_seed($Val) {
 620     /* if mt_getrandmax() does not return a 2^n - 1 number,
 621        this might not work well.  This uses $Max as a bitmask. */
 622     $Max = mt_getrandmax();
 623
 624     if (! is_int($Val)) {
 625             $Val = crc32($Val);
 626     }
 627
 628     if ($Val < 0) {
 629         $Val *= -1;
 630     }
 631
 632     if ($Val == 0) {
 633         return;
 634     }
 635
 636     mt_srand(($Val ^ mt_rand(0, $Max)) & $Max);
 637 }
 638
 639
 640 /**
 641  * Init random number generator
 642  *
 643  * This function initializes the random number generator fairly well.
 644  * It also only initializes it once, so you don't accidentally get
 645  * the same 'random' numbers twice in one session.
 646  *
 647  * @return void
 648  * @since 1.0
 649  */
 650 function sq_mt_randomize() {
 651     static $randomized;
 652
 653     if ($randomized) {
 654         return;
 655     }
 656
 657     /* Global. */
 658     sqgetGlobalVar('REMOTE_PORT', $remote_port, SQ_SERVER);
 659     sqgetGlobalVar('REMOTE_ADDR', $remote_addr, SQ_SERVER);
 660     sq_mt_seed((int)((double) microtime() * 1000000));
 661     sq_mt_seed(md5($remote_port . $remote_addr . getmypid()));
 662
 663     /* getrusage */
 664     if (function_exists('getrusage')) {
 665         /* Avoid warnings with Win32 */
 666         $dat = @getrusage();
 667         if (isset($dat) && is_array($dat)) {
 668             $Str = '';
 669             foreach ($dat as $k => $v)
 670                 {
 671                     $Str .= $k . $v;
 672                 }
 673             sq_mt_seed(md5($Str));
 674         }
 675     }
 676
 677     if(sqgetGlobalVar('UNIQUE_ID', $unique_id, SQ_SERVER)) {
 678         sq_mt_seed(md5($unique_id));
 679     }
 680
 681     $randomized = 1;
 682 }
 683
 684 /**
 685  * Creates encryption key
 686  *
 687  * Creates an encryption key for encrypting the password stored in the cookie.
 688  * The encryption key itself is stored in the session.
 689  *
 690  * Pad must be longer or equal to encoded string length in 1.4.4/1.5.0 and older.
 691  * @param int $length optional, length of the string to generate
 692  * @return string the encryption key
 693  * @since 1.0
 694  */
 695 function OneTimePadCreate ($length=100) {
 696     sq_mt_randomize();
 697
 698     $pad = '';
 699     for ($i = 0; $i < $length; $i++) {
 700         $pad .= chr(mt_rand(0,255));
 701     }
 702
 703     return base64_encode($pad);
 704 }
 705
 706 /**
 707  * Returns a string showing the size of the message/attachment.
 708  *
 709  * @param int $bytes the filesize in bytes
 710  * @return string the filesize in human readable format
 711  * @since 1.0
 712  */
 713 function show_readable_size($bytes) {
 714     $bytes /= 1024;
 715     $type = 'KiB';
 716
 717     if ($bytes / 1024 > 1) {
 718         $bytes /= 1024;
 719         $type = 'MiB';
 720     }
 721
 722     if ($bytes < 10) {
 723         $bytes *= 10;
 724         settype($bytes, 'integer');
 725         $bytes /= 10;
 726     } else {
 727         settype($bytes, 'integer');
 728     }
 729
 730     return $bytes . '&nbsp;' . $type;
 731 }
 732
 733 /**
 734  * Generates a random string from the character set you pass in
 735  *
 736  * @param int $size the length of the string to generate
 737  * @param string $chars a string containing the characters to use
 738  * @param int $flags a flag to add a specific set to the characters to use:
 739  *     Flags:
 740  *       1 = add lowercase a-z to $chars
 741  *       2 = add uppercase A-Z to $chars
 742  *       4 = add numbers 0-9 to $chars
 743  * @return string the random string
 744  * @since 1.0
 745  */
 746 function GenerateRandomString($size, $chars, $flags = 0) {
 747     if ($flags & 0x1) {
 748         $chars .= 'abcdefghijklmnopqrstuvwxyz';
 749     }
 750     if ($flags & 0x2) {
 751         $chars .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
 752     }
 753     if ($flags & 0x4) {
 754         $chars .= '0123456789';
 755     }
 756
 757     if (($size < 1) || (strlen($chars) < 1)) {
 758         return '';
 759     }
 760
 761     sq_mt_randomize(); /* Initialize the random number generator */
 762
 763     $String = '';
 764     $j = strlen( $chars ) - 1;
 765     while (strlen($String) < $size) {
 766         $String .= $chars{mt_rand(0, $j)};
 767     }
 768
 769     return $String;
 770 }
 771
 772 /**
 773  * Escapes special characters for use in IMAP commands.
 774  *
 775  * @param string $str the string to escape
 776  * @return string the escaped string
 777  * @since 1.0.3
 778  */
 779 function quoteimap($str) {
 780     return preg_replace("/([\"\\\\])/", "\\\\$1", $str);
 781 }
 782
 783 /**
 784  * Trims array
 785  *
 786  * Trims every element in the array, ie. remove the first char of each element
 787  * @param array $array the array to trim
 788  * @since 1.2.0
 789  */
 790 function TrimArray(&$array) {
 791     foreach ($array as $k => $v) {
 792         global $$k;
 793         if (is_array($$k)) {
 794             foreach ($$k as $k2 => $v2) {
 795                 $$k[$k2] = substr($v2, 1);
 796             }
 797         } else {
 798             $$k = substr($v, 1);
 799         }
 800
 801         /* Re-assign back to array. */
 802         $array[$k] = $$k;
 803     }
 804 }
 805
 806 /**
 807  * Create compose link
 808  *
 809  * Returns a link to the compose-page, taking in consideration
 810  * the compose_in_new and javascript settings.
 811  * @param string $url the URL to the compose page
 812  * @param string $text the link text, default "Compose"
 813  * @param string $target (since 1.4.3) url target
 814  * @return string a link to the compose page
 815  * @since 1.4.2
 816  */
 817 function makeComposeLink($url, $text = null, $target='') {
 818     global $compose_new_win,$javascript_on, $compose_width, $compose_height;
 819
 820     if(!$text) {
 821         $text = _("Compose");
 822     }
 823
 824     // if not using "compose in new window", make
 825     // regular link and be done with it
 826     if($compose_new_win != '1') {
 827         return makeInternalLink($url, $text, $target);
 828     }
 829
 830     // build the compose in new window link...
 831
 832
 833     // if javascript is on, use onclick event to handle it
 834     if($javascript_on) {
 835         sqgetGlobalVar('base_uri', $base_uri, SQ_SESSION);
 836         $compuri = SM_BASE_URI.$url;
 837         return "<a href=\"javascript:void(0)\" onclick=\"comp_in_new('$compuri','$compose_width','$compose_height')\">$text</a>";
 838     }
 839
 840     // otherwise, just open new window using regular HTML
 841     return makeInternalLink($url, $text, '_blank');
 842 }
 843
 844 /**
 845  * Print variable
 846  *
 847  * sm_print_r($some_variable, [$some_other_variable [, ...]]);
 848  *
 849  * Debugging function - does the same as print_r, but makes sure special
 850  * characters are converted to htmlentities first.  This will allow
 851  * values like <some@email.address> to be displayed.
 852  * The output is wrapped in <<pre>> and <</pre>> tags.
 853  * Since 1.4.2 accepts unlimited number of arguments.
 854  * @since 1.4.1
 855  * @return void
 856  */
 857 function sm_print_r() {
 858     ob_start();  // Buffer output
 859     foreach(func_get_args() as $var) {
 860         print_r($var);
 861         echo "\n";
 862         // php has get_class_methods function that can print class methods
 863         if (is_object($var)) {
 864             // get class methods if $var is object
 865             $aMethods=get_class_methods(get_class($var));
 866             // make sure that $aMethods is array and array is not empty
 867             if (is_array($aMethods) && $aMethods!=array()) {
 868                 echo "Object methods:\n";
 869                 foreach($aMethods as $method) {
 870                     echo '* ' . $method . "\n";
 871                 }
 872             }
 873             echo "\n";
 874         }
 875     }
 876     $buffer = ob_get_contents(); // Grab the print_r output
 877     ob_end_clean();  // Silently discard the output & stop buffering
 878     print '<div align="left"><pre>';
 879     print htmlentities($buffer);
 880     print '</pre></div>';
 881 }
 882
 883 /**
 884  * version of fwrite which checks for failure
 885  * @param resource $fp
 886  * @param string $string
 887  * @return number of written bytes. false on failure
 888  * @since 1.4.3
 889  */
 890 function sq_fwrite($fp, $string) {
 891         // write to file
 892         $count = @fwrite($fp,$string);
 893         // the number of bytes written should be the length of the string
 894         if($count != strlen($string)) {
 895                 return FALSE;
 896         }
 897
 898         return $count;
 899 }
 900
 901 /**
 902  * sq_get_html_translation_table
 903  *
 904  * Returns the translation table used by sq_htmlentities()
 905  *
 906  * @param integer $table html translation table. Possible values (without quotes):
 907  *             <ul>
 908  *                <li>HTML_ENTITIES - full html entities table defined by charset</li>
 909  *                <li>HTML_SPECIALCHARS - html special characters table</li>
 910  *             </ul>
 911  * @param integer $quote_style quote encoding style. Possible values (without quotes):
 912  *              <ul>
 913  *                <li>ENT_COMPAT - (default) encode double quotes</li>
 914  *                <li>ENT_NOQUOTES -  don't encode double or single quotes</li>
 915  *                <li>ENT_QUOTES - encode double and single quotes</li>
 916  *              </ul>
 917  * @param string $charset charset used for encoding. default to us-ascii, 'auto' uses $default_charset global value.
 918  * @return array html translation array
 919  * @since 1.5.1
 920  */
 921 function sq_get_html_translation_table($table,$quote_style=ENT_COMPAT,$charset='us-ascii') {
 922   global $default_charset;
 923
 924   if ($table == HTML_SPECIALCHARS) $charset='us-ascii';
 925
 926   // Start array with ampersand
 927   $sq_html_ent_table = array( "&" => '&amp;' );
 928
 929   // < and >
 930   $sq_html_ent_table = array_merge($sq_html_ent_table,
 931                         array("<" => '&lt;',
 932                               ">" => '&gt;')
 933                         );
 934   // double quotes
 935   if ($quote_style == ENT_COMPAT)
 936      $sq_html_ent_table = array_merge($sq_html_ent_table,
 937                             array("\"" => '&quot;')
 938                             );
 939
 940   // double and single quotes
 941   if ($quote_style == ENT_QUOTES)
 942      $sq_html_ent_table = array_merge($sq_html_ent_table,
 943                             array("\"" => '&quot;',
 944                               "'" => '&#39;')
 945                             );
 946
 947   if ($charset=='auto') $charset=$default_charset;
 948
 949   // add entities that depend on charset
 950   switch($charset){
 951   case 'iso-8859-1':
 952     include_once(SM_PATH . 'functions/htmlentities/iso-8859-1.php');
 953     break;
 954   case 'utf-8':
 955     include_once(SM_PATH . 'functions/htmlentities/utf-8.php');
 956     break;
 957   case 'us-ascii':
 958   default:
 959     break;
 960   }
 961   // return table
 962   return $sq_html_ent_table;
 963 }
 964
 965 /**
 966  * sq_htmlentities
 967  *
 968  * Convert all applicable characters to HTML entities.
 969  * Minimal php requirement - v.4.0.5.
 970  *
 971  * Function is designed for people that want to use full power of htmlentities() in
 972  * i18n environment.
 973  *
 974  * @param string $string string that has to be sanitized
 975  * @param integer $quote_style quote encoding style. Possible values (without quotes):
 976  *              <ul>
 977  *                <li>ENT_COMPAT - (default) encode double quotes</li>
 978  *                <li>ENT_NOQUOTES - don't encode double or single quotes</li>
 979  *                <li>ENT_QUOTES - encode double and single quotes</li>
 980  *              </ul>
 981  * @param string $charset charset used for encoding. defaults to 'us-ascii', 'auto' uses $default_charset global value.
 982  * @return string sanitized string
 983  * @since 1.5.1
 984  */
 985 function sq_htmlentities($string,$quote_style=ENT_COMPAT,$charset='us-ascii') {
 986   // get translation table
 987   $sq_html_ent_table=sq_get_html_translation_table(HTML_ENTITIES,$quote_style,$charset);
 988   // convert characters
 989   return str_replace(array_keys($sq_html_ent_table),array_values($sq_html_ent_table),$string);
 990 }
 991
 992 /**
 993  * Tests if string contains 8bit symbols.
 994  *
 995  * If charset is not set, function defaults to default_charset.
 996  * $default_charset global must be set correctly if $charset is
 997  * not used.
 998  * @param string $string tested string
 999  * @param string $charset charset used in a string
1000  * @return bool true if 8bit symbols are detected
1001  * @since 1.5.1 and 1.4.4
1002  */
1003 function sq_is8bit($string,$charset='') {
1004     global $default_charset;
1005
1006     if ($charset=='') $charset=$default_charset;
1007
1008     /**
1009      * Don't use \240 in ranges. Sometimes RH 7.2 doesn't like it.
1010      * Don't use \200-\237 for iso-8859-x charsets. This range
1011      * stores control symbols in those charsets.
1012      * Use preg_match instead of ereg in order to avoid problems
1013      * with mbstring overloading
1014      */
1015     if (preg_match("/^iso-8859/i",$charset)) {
1016         $needle='/\240|[\241-\377]/';
1017     } else {
1018         $needle='/[\200-\237]|\240|[\241-\377]/';
1019     }
1020     return preg_match("$needle",$string);
1021 }
1022
1023 /**
1024  * Replacement of mb_list_encodings function
1025  *
1026  * This function provides replacement for function that is available only
1027  * in php 5.x. Function does not test all mbstring encodings. Only the ones
1028  * that might be used in SM translations.
1029  *
1030  * Supported strings are stored in session in order to reduce number of
1031  * mb_internal_encoding function calls.
1032  *
1033  * If you want to test all mbstring encodings - fill $list_of_encodings
1034  * array.
1035  * @return array list of encodings supported by php mbstring extension
1036  * @since 1.5.1 and 1.4.6
1037  */
1038 function sq_mb_list_encodings() {
1039     if (! function_exists('mb_internal_encoding'))
1040         return array();
1041
1042     // php 5+ function
1043     if (function_exists('mb_list_encodings')) {
1044         $ret = mb_list_encodings();
1045         array_walk($ret,'sq_lowercase_array_vals');
1046         return $ret;
1047     }
1048
1049     // don't try to test encodings, if they are already stored in session
1050     if (sqgetGlobalVar('mb_supported_encodings',$mb_supported_encodings,SQ_SESSION))
1051         return $mb_supported_encodings;
1052
1053     // save original encoding
1054     $orig_encoding=mb_internal_encoding();
1055
1056     $list_of_encoding=array(
1057         'pass',
1058         'auto',
1059         'ascii',
1060         'jis',
1061         'utf-8',
1062         'sjis',
1063         'euc-jp',
1064         'iso-8859-1',
1065         'iso-8859-2',
1066         'iso-8859-7',
1067         'iso-8859-9',
1068         'iso-8859-15',
1069         'koi8-r',
1070         'koi8-u',
1071         'big5',
1072         'gb2312',
1073         'gb18030',
1074         'windows-1251',
1075         'windows-1255',
1076         'windows-1256',
1077         'tis-620',
1078         'iso-2022-jp',
1079         'euc-cn',
1080         'euc-kr',
1081         'euc-tw',
1082         'uhc',
1083         'utf7-imap');
1084
1085     $supported_encodings=array();
1086
1087     foreach ($list_of_encoding as $encoding) {
1088         // try setting encodings. suppress warning messages
1089         if (@mb_internal_encoding($encoding))
1090             $supported_encodings[]=$encoding;
1091     }
1092
1093     // restore original encoding
1094     mb_internal_encoding($orig_encoding);
1095
1096     // register list in session
1097     sqsession_register($supported_encodings,'mb_supported_encodings');
1098
1099     return $supported_encodings;
1100 }
1101
1102 /**
1103  * Callback function used to lowercase array values.
1104  * @param string $val array value
1105  * @param mixed $key array key
1106  * @since 1.5.1 and 1.4.6
1107  */
1108 function sq_lowercase_array_vals(&$val,$key) {
1109     $val = strtolower($val);
1110 }
1111
1112
1113 /**
1114  * Function returns number of characters in string.
1115  *
1116  * Returned number might be different from number of bytes in string,
1117  * if $charset is multibyte charset. Detection depends on mbstring
1118  * functions. If mbstring does not support tested multibyte charset,
1119  * vanilla string length function is used.
1120  * @param string $str string
1121  * @param string $charset charset
1122  * @since 1.5.1 and 1.4.6
1123  * @return integer number of characters in string
1124  */
1125 function sq_strlen($str, $charset=null){
1126     // default option
1127     if (is_null($charset)) return strlen($str);
1128
1129     // lowercase charset name
1130     $charset=strtolower($charset);
1131
1132     // use automatic charset detection, if function call asks for it
1133     if ($charset=='auto') {
1134         global $default_charset, $squirrelmail_language;
1135         set_my_charset();
1136         $charset=$default_charset;
1137         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1138     }
1139
1140     // Use mbstring only with listed charsets
1141     $aList_of_mb_charsets=array('utf-8','big5','gb2312','gb18030','euc-jp','euc-cn','euc-tw','euc-kr');
1142
1143     // calculate string length according to charset
1144     if (in_array($charset,$aList_of_mb_charsets) && in_array($charset,sq_mb_list_encodings())) {
1145         $real_length = mb_strlen($str,$charset);
1146     } else {
1147         // own strlen detection code is removed because missing strpos,
1148         // strtoupper and substr implementations break string wrapping.
1149         $real_length=strlen($str);
1150     }
1151     return $real_length;
1152 }
1153
1154 /**
1155  * string padding with multibyte support
1156  *
1157  * @link http://www.php.net/str_pad
1158  * @param string $string original string
1159  * @param integer $width padded string width
1160  * @param string $pad padding symbols
1161  * @param integer $padtype padding type
1162  *  (internal php defines, see str_pad() description)
1163  * @param string $charset charset used in original string
1164  * @return string padded string
1165  */
1166 function sq_str_pad($string, $width, $pad, $padtype, $charset='') {
1167
1168     $charset = strtolower($charset);
1169     $padded_string = '';
1170
1171     switch ($charset) {
1172     case 'utf-8':
1173     case 'big5':
1174     case 'gb2312':
1175     case 'euc-kr':
1176         /*
1177          * all multibyte charsets try to increase width value by
1178          * adding difference between number of bytes and real length
1179          */
1180         $width = $width - sq_strlen($string,$charset) + strlen($string);
1181     default:
1182         $padded_string=str_pad($string,$width,$pad,$padtype);
1183     }
1184     return $padded_string;
1185 }
1186
1187 /**
1188  * Wrapper that is used to switch between vanilla and multibyte substr
1189  * functions.
1190  * @param string $string
1191  * @param integer $start
1192  * @param integer $length
1193  * @param string $charset
1194  * @return string
1195  * @since 1.5.1
1196  * @link http://www.php.net/substr
1197  * @link http://www.php.net/mb_substr
1198  */
1199 function sq_substr($string,$start,$length,$charset='auto') {
1200     // use automatic charset detection, if function call asks for it
1201     if ($charset=='auto') {
1202         global $default_charset, $squirrelmail_language;
1203         set_my_charset();
1204         $charset=$default_charset;
1205         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1206     }
1207     $charset = strtolower($charset);
1208     if (function_exists('mb_internal_encoding') &&
1209         in_array($charset,sq_mb_list_encodings())) {
1210         return mb_substr($string,$start,$length,$charset);
1211     }
1212     // TODO: add mbstring independent code
1213
1214     // use vanilla string functions as last option
1215     return substr($string,$start,$length);
1216 }
1217
1218 /**
1219  * Wrapper that is used to switch between vanilla and multibyte strpos
1220  * functions.
1221  * @param string $haystack
1222  * @param mixed $needle
1223  * @param integer $offset
1224  * @param string $charset
1225  * @return string
1226  * @since 1.5.1
1227  * @link http://www.php.net/strpos
1228  * @link http://www.php.net/mb_strpos
1229  */
1230 function sq_strpos($haystack,$needle,$offset,$charset='auto') {
1231     // use automatic charset detection, if function call asks for it
1232     if ($charset=='auto') {
1233         global $default_charset, $squirrelmail_language;
1234         set_my_charset();
1235         $charset=$default_charset;
1236         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1237     }
1238     $charset = strtolower($charset);
1239     if (function_exists('mb_internal_encoding') &&
1240         in_array($charset,sq_mb_list_encodings())) {
1241         return mb_strpos($haystack,$needle,$offset,$charset);
1242     }
1243     // TODO: add mbstring independent code
1244
1245     // use vanilla string functions as last option
1246     return strpos($haystack,$needle,$offset);
1247 }
1248
1249 /**
1250  * Wrapper that is used to switch between vanilla and multibyte strtoupper
1251  * functions.
1252  * @param string $string
1253  * @param string $charset
1254  * @return string
1255  * @since 1.5.1
1256  * @link http://www.php.net/strtoupper
1257  * @link http://www.php.net/mb_strtoupper
1258  */
1259 function sq_strtoupper($string,$charset='auto') {
1260     // use automatic charset detection, if function call asks for it
1261     if ($charset=='auto') {
1262         global $default_charset,$squirrelmail_language;
1263         set_my_charset();
1264         $charset=$default_charset;
1265         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1266     }
1267     $charset = strtolower($charset);
1268     if (function_exists('mb_strtoupper') &&
1269         in_array($charset,sq_mb_list_encodings())) {
1270         return mb_strtoupper($string,$charset);
1271     }
1272     // TODO: add mbstring independent code
1273
1274     // use vanilla string functions as last option
1275     return strtoupper($string);
1276 }
1277
1278 /**
1279  * Counts 8bit bytes in string
1280  * @param string $string tested string
1281  * @return integer number of 8bit bytes
1282  */
1283 function sq_count8bit($string) {
1284     $count=0;
1285     for ($i=0; $i<strlen($string); $i++) {
1286         if (ord($string[$i]) > 127) $count++;
1287     }
1288     return $count;
1289 }
1290
1291 /**
1292  * Callback function to trim whitespace from a value, to be used in array_walk
1293  * @param string $value value to trim
1294  * @since 1.5.2 and 1.4.7
1295  */
1296 function sq_trim_value ( &$value ) {
1297     $value = trim($value);
1298 }