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  * If this doesnt work correctly for you (although it should), you can
 464  * remove all this code except the last two lines, and have it return
 465  * the right URL for your site, something like:
 466  *
 467  *   http://www.example.com/squirrelmail/
 468  *
 469  * @return string the base url for this SquirrelMail installation
 470  * @since 1.0
 471  */
 472 function get_location () {
 473
 474     global $imap_server_type;
 475
 476     /* Get the path, handle virtual directories */
 477     if(strpos(php_self(), '?')) {
 478         $path = substr(php_self(), 0, strpos(php_self(), '?'));
 479     } else {
 480         $path = php_self();
 481     }
 482     $path = substr($path, 0, strrpos($path, '/'));
 483     if ( sqgetGlobalVar('sq_base_url', $full_url, SQ_SESSION) ) {
 484       return $full_url . $path;
 485     }
 486
 487     /* Check if this is a HTTPS or regular HTTP request. */
 488     $proto = 'http://';
 489
 490     /*
 491      * If you have 'SSLOptions +StdEnvVars' in your apache config
 492      *     OR if you have HTTPS=on in your HTTP_SERVER_VARS
 493      *     OR if you are on port 443
 494      */
 495     $getEnvVar = getenv('HTTPS');
 496     if ((isset($getEnvVar) && strcasecmp($getEnvVar, 'on') === 0) ||
 497         (sqgetGlobalVar('HTTPS', $https_on, SQ_SERVER) && strcasecmp($https_on, 'on') === 0) ||
 498         (sqgetGlobalVar('SERVER_PORT', $server_port, SQ_SERVER) &&  $server_port == 443)) {
 499         $proto = 'https://';
 500     }
 501
 502     /* Get the hostname from the Host header or server config. */
 503     if ( !sqgetGlobalVar('HTTP_X_FORWARDED_HOST', $host, SQ_SERVER) || empty($host) ) {
 504         if ( !sqgetGlobalVar('HTTP_HOST', $host, SQ_SERVER) || empty($host) ) {
 505             if ( !sqgetGlobalVar('SERVER_NAME', $host, SQ_SERVER) || empty($host) ) {
 506                 $host = '';
 507             }
 508         }
 509     }
 510
 511     $port = '';
 512     if (! strstr($host, ':')) {
 513         if (sqgetGlobalVar('SERVER_PORT', $server_port, SQ_SERVER)) {
 514             if (($server_port != 80 && $proto == 'http://') ||
 515                 ($server_port != 443 && $proto == 'https://')) {
 516                 $port = sprintf(':%d', $server_port);
 517             }
 518         }
 519     }
 520
 521    /* this is a workaround for the weird macosx caching that
 522       causes Apache to return 16080 as the port number, which causes
 523       SM to bail */
 524
 525    if ($imap_server_type == 'macosx' && $port == ':16080') {
 526         $port = '';
 527    }
 528
 529    /* Fallback is to omit the server name and use a relative */
 530    /* URI, although this is not RFC 2616 compliant.          */
 531    $full_url = ($host ? $proto . $host . $port : '');
 532    sqsession_register($full_url, 'sq_base_url');
 533    return $full_url . $path;
 534 }
 535
 536
 537 /**
 538  * Encrypts password
 539  *
 540  * These functions are used to encrypt the password before it is
 541  * stored in a cookie. The encryption key is generated by
 542  * OneTimePadCreate();
 543  *
 544  * @param string $string the (password)string to encrypt
 545  * @param string $epad the encryption key
 546  * @return string the base64-encoded encrypted password
 547  * @since 1.0
 548  */
 549 function OneTimePadEncrypt ($string, $epad) {
 550     $pad = base64_decode($epad);
 551
 552     if (strlen($pad)>0) {
 553         // make sure that pad is longer than string
 554         while (strlen($string)>strlen($pad)) {
 555             $pad.=$pad;
 556         }
 557     } else {
 558         // FIXME: what should we do when $epad is not base64 encoded or empty.
 559     }
 560
 561     $encrypted = '';
 562     for ($i = 0; $i < strlen ($string); $i++) {
 563         $encrypted .= chr (ord($string[$i]) ^ ord($pad[$i]));
 564     }
 565
 566     return base64_encode($encrypted);
 567 }
 568
 569 /**
 570  * Decrypts a password from the cookie
 571  *
 572  * Decrypts a password from the cookie, encrypted by OneTimePadEncrypt.
 573  * This uses the encryption key that is stored in the session.
 574  *
 575  * @param string $string the string to decrypt
 576  * @param string $epad the encryption key from the session
 577  * @return string the decrypted password
 578  * @since 1.0
 579  */
 580 function OneTimePadDecrypt ($string, $epad) {
 581     $pad = base64_decode($epad);
 582
 583     if (strlen($pad)>0) {
 584         // make sure that pad is longer than string
 585         while (strlen($string)>strlen($pad)) {
 586             $pad.=$pad;
 587         }
 588     } else {
 589         // FIXME: what should we do when $epad is not base64 encoded or empty.
 590     }
 591
 592     $encrypted = base64_decode ($string);
 593     $decrypted = '';
 594     for ($i = 0; $i < strlen ($encrypted); $i++) {
 595         $decrypted .= chr (ord($encrypted[$i]) ^ ord($pad[$i]));
 596     }
 597
 598     return $decrypted;
 599 }
 600
 601
 602 /**
 603  * Randomizes the mt_rand() function.
 604  *
 605  * Toss this in strings or integers and it will seed the generator
 606  * appropriately. With strings, it is better to get them long.
 607  * Use md5() to lengthen smaller strings.
 608  *
 609  * @param mixed $val a value to seed the random number generator. mixed = integer or string.
 610  * @return void
 611  * @since 1.0
 612  */
 613 function sq_mt_seed($Val) {
 614     /* if mt_getrandmax() does not return a 2^n - 1 number,
 615        this might not work well.  This uses $Max as a bitmask. */
 616     $Max = mt_getrandmax();
 617
 618     if (! is_int($Val)) {
 619             $Val = crc32($Val);
 620     }
 621
 622     if ($Val < 0) {
 623         $Val *= -1;
 624     }
 625
 626     if ($Val == 0) {
 627         return;
 628     }
 629
 630     mt_srand(($Val ^ mt_rand(0, $Max)) & $Max);
 631 }
 632
 633
 634 /**
 635  * Init random number generator
 636  *
 637  * This function initializes the random number generator fairly well.
 638  * It also only initializes it once, so you don't accidentally get
 639  * the same 'random' numbers twice in one session.
 640  *
 641  * @return void
 642  * @since 1.0
 643  */
 644 function sq_mt_randomize() {
 645     static $randomized;
 646
 647     if ($randomized) {
 648         return;
 649     }
 650
 651     /* Global. */
 652     sqgetGlobalVar('REMOTE_PORT', $remote_port, SQ_SERVER);
 653     sqgetGlobalVar('REMOTE_ADDR', $remote_addr, SQ_SERVER);
 654     sq_mt_seed((int)((double) microtime() * 1000000));
 655     sq_mt_seed(md5($remote_port . $remote_addr . getmypid()));
 656
 657     /* getrusage */
 658     if (function_exists('getrusage')) {
 659         /* Avoid warnings with Win32 */
 660         $dat = @getrusage();
 661         if (isset($dat) && is_array($dat)) {
 662             $Str = '';
 663             foreach ($dat as $k => $v)
 664                 {
 665                     $Str .= $k . $v;
 666                 }
 667             sq_mt_seed(md5($Str));
 668         }
 669     }
 670
 671     if(sqgetGlobalVar('UNIQUE_ID', $unique_id, SQ_SERVER)) {
 672         sq_mt_seed(md5($unique_id));
 673     }
 674
 675     $randomized = 1;
 676 }
 677
 678 /**
 679  * Creates encryption key
 680  *
 681  * Creates an encryption key for encrypting the password stored in the cookie.
 682  * The encryption key itself is stored in the session.
 683  *
 684  * Pad must be longer or equal to encoded string length in 1.4.4/1.5.0 and older.
 685  * @param int $length optional, length of the string to generate
 686  * @return string the encryption key
 687  * @since 1.0
 688  */
 689 function OneTimePadCreate ($length=100) {
 690     sq_mt_randomize();
 691
 692     $pad = '';
 693     for ($i = 0; $i < $length; $i++) {
 694         $pad .= chr(mt_rand(0,255));
 695     }
 696
 697     return base64_encode($pad);
 698 }
 699
 700 /**
 701  * Returns a string showing the size of the message/attachment.
 702  *
 703  * @param int $bytes the filesize in bytes
 704  * @return string the filesize in human readable format
 705  * @since 1.0
 706  */
 707 function show_readable_size($bytes) {
 708     $bytes /= 1024;
 709     $type = 'KiB';
 710
 711     if ($bytes / 1024 > 1) {
 712         $bytes /= 1024;
 713         $type = 'MiB';
 714     }
 715
 716     if ($bytes < 10) {
 717         $bytes *= 10;
 718         settype($bytes, 'integer');
 719         $bytes /= 10;
 720     } else {
 721         settype($bytes, 'integer');
 722     }
 723
 724     return $bytes . '&nbsp;' . $type;
 725 }
 726
 727 /**
 728  * Generates a random string from the character set you pass in
 729  *
 730  * @param int $size the length of the string to generate
 731  * @param string $chars a string containing the characters to use
 732  * @param int $flags a flag to add a specific set to the characters to use:
 733  *     Flags:
 734  *       1 = add lowercase a-z to $chars
 735  *       2 = add uppercase A-Z to $chars
 736  *       4 = add numbers 0-9 to $chars
 737  * @return string the random string
 738  * @since 1.0
 739  */
 740 function GenerateRandomString($size, $chars, $flags = 0) {
 741     if ($flags & 0x1) {
 742         $chars .= 'abcdefghijklmnopqrstuvwxyz';
 743     }
 744     if ($flags & 0x2) {
 745         $chars .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
 746     }
 747     if ($flags & 0x4) {
 748         $chars .= '0123456789';
 749     }
 750
 751     if (($size < 1) || (strlen($chars) < 1)) {
 752         return '';
 753     }
 754
 755     sq_mt_randomize(); /* Initialize the random number generator */
 756
 757     $String = '';
 758     $j = strlen( $chars ) - 1;
 759     while (strlen($String) < $size) {
 760         $String .= $chars{mt_rand(0, $j)};
 761     }
 762
 763     return $String;
 764 }
 765
 766 /**
 767  * Escapes special characters for use in IMAP commands.
 768  *
 769  * @param string $str the string to escape
 770  * @return string the escaped string
 771  * @since 1.0.3
 772  */
 773 function quoteimap($str) {
 774     return preg_replace("/([\"\\\\])/", "\\\\$1", $str);
 775 }
 776
 777 /**
 778  * Trims array
 779  *
 780  * Trims every element in the array, ie. remove the first char of each element
 781  * @param array $array the array to trim
 782  * @since 1.2.0
 783  */
 784 function TrimArray(&$array) {
 785     foreach ($array as $k => $v) {
 786         global $$k;
 787         if (is_array($$k)) {
 788             foreach ($$k as $k2 => $v2) {
 789                 $$k[$k2] = substr($v2, 1);
 790             }
 791         } else {
 792             $$k = substr($v, 1);
 793         }
 794
 795         /* Re-assign back to array. */
 796         $array[$k] = $$k;
 797     }
 798 }
 799
 800 /**
 801  * Create compose link
 802  *
 803  * Returns a link to the compose-page, taking in consideration
 804  * the compose_in_new and javascript settings.
 805  * @param string $url the URL to the compose page
 806  * @param string $text the link text, default "Compose"
 807  * @param string $target (since 1.4.3) url target
 808  * @return string a link to the compose page
 809  * @since 1.4.2
 810  */
 811 function makeComposeLink($url, $text = null, $target='') {
 812     global $compose_new_win,$javascript_on, $compose_width, $compose_height;
 813
 814     if(!$text) {
 815         $text = _("Compose");
 816     }
 817
 818     // if not using "compose in new window", make
 819     // regular link and be done with it
 820     if($compose_new_win != '1') {
 821         return makeInternalLink($url, $text, $target);
 822     }
 823
 824     // build the compose in new window link...
 825
 826
 827     // if javascript is on, use onclick event to handle it
 828     if($javascript_on) {
 829         sqgetGlobalVar('base_uri', $base_uri, SQ_SESSION);
 830         $compuri = SM_BASE_URI.$url;
 831         return "<a href=\"javascript:void(0)\" onclick=\"comp_in_new('$compuri','$compose_width','$compose_height')\">$text</a>";
 832     }
 833
 834     // otherwise, just open new window using regular HTML
 835     return makeInternalLink($url, $text, '_blank');
 836 }
 837
 838 /**
 839  * Print variable
 840  *
 841  * sm_print_r($some_variable, [$some_other_variable [, ...]]);
 842  *
 843  * Debugging function - does the same as print_r, but makes sure special
 844  * characters are converted to htmlentities first.  This will allow
 845  * values like <some@email.address> to be displayed.
 846  * The output is wrapped in <<pre>> and <</pre>> tags.
 847  * Since 1.4.2 accepts unlimited number of arguments.
 848  * @since 1.4.1
 849  * @return void
 850  */
 851 function sm_print_r() {
 852     ob_start();  // Buffer output
 853     foreach(func_get_args() as $var) {
 854         print_r($var);
 855         echo "\n";
 856         // php has get_class_methods function that can print class methods
 857         if (is_object($var)) {
 858             // get class methods if $var is object
 859             $aMethods=get_class_methods(get_class($var));
 860             // make sure that $aMethods is array and array is not empty
 861             if (is_array($aMethods) && $aMethods!=array()) {
 862                 echo "Object methods:\n";
 863                 foreach($aMethods as $method) {
 864                     echo '* ' . $method . "\n";
 865                 }
 866             }
 867             echo "\n";
 868         }
 869     }
 870     $buffer = ob_get_contents(); // Grab the print_r output
 871     ob_end_clean();  // Silently discard the output & stop buffering
 872     print '<div align="left"><pre>';
 873     print htmlentities($buffer);
 874     print '</pre></div>';
 875 }
 876
 877 /**
 878  * version of fwrite which checks for failure
 879  * @param resource $fp
 880  * @param string $string
 881  * @return number of written bytes. false on failure
 882  * @since 1.4.3
 883  */
 884 function sq_fwrite($fp, $string) {
 885         // write to file
 886         $count = @fwrite($fp,$string);
 887         // the number of bytes written should be the length of the string
 888         if($count != strlen($string)) {
 889                 return FALSE;
 890         }
 891
 892         return $count;
 893 }
 894
 895 /**
 896  * sq_get_html_translation_table
 897  *
 898  * Returns the translation table used by sq_htmlentities()
 899  *
 900  * @param integer $table html translation table. Possible values (without quotes):
 901  *             <ul>
 902  *                <li>HTML_ENTITIES - full html entities table defined by charset</li>
 903  *                <li>HTML_SPECIALCHARS - html special characters table</li>
 904  *             </ul>
 905  * @param integer $quote_style quote encoding style. Possible values (without quotes):
 906  *              <ul>
 907  *                <li>ENT_COMPAT - (default) encode double quotes</li>
 908  *                <li>ENT_NOQUOTES -  don't encode double or single quotes</li>
 909  *                <li>ENT_QUOTES - encode double and single quotes</li>
 910  *              </ul>
 911  * @param string $charset charset used for encoding. default to us-ascii, 'auto' uses $default_charset global value.
 912  * @return array html translation array
 913  * @since 1.5.1
 914  */
 915 function sq_get_html_translation_table($table,$quote_style=ENT_COMPAT,$charset='us-ascii') {
 916   global $default_charset;
 917
 918   if ($table == HTML_SPECIALCHARS) $charset='us-ascii';
 919
 920   // Start array with ampersand
 921   $sq_html_ent_table = array( "&" => '&amp;' );
 922
 923   // < and >
 924   $sq_html_ent_table = array_merge($sq_html_ent_table,
 925                         array("<" => '&lt;',
 926                               ">" => '&gt;')
 927                         );
 928   // double quotes
 929   if ($quote_style == ENT_COMPAT)
 930      $sq_html_ent_table = array_merge($sq_html_ent_table,
 931                             array("\"" => '&quot;')
 932                             );
 933
 934   // double and single quotes
 935   if ($quote_style == ENT_QUOTES)
 936      $sq_html_ent_table = array_merge($sq_html_ent_table,
 937                             array("\"" => '&quot;',
 938                               "'" => '&#39;')
 939                             );
 940
 941   if ($charset=='auto') $charset=$default_charset;
 942
 943   // add entities that depend on charset
 944   switch($charset){
 945   case 'iso-8859-1':
 946     include_once(SM_PATH . 'functions/htmlentities/iso-8859-1.php');
 947     break;
 948   case 'utf-8':
 949     include_once(SM_PATH . 'functions/htmlentities/utf-8.php');
 950     break;
 951   case 'us-ascii':
 952   default:
 953     break;
 954   }
 955   // return table
 956   return $sq_html_ent_table;
 957 }
 958
 959 /**
 960  * sq_htmlentities
 961  *
 962  * Convert all applicable characters to HTML entities.
 963  * Minimal php requirement - v.4.0.5.
 964  *
 965  * Function is designed for people that want to use full power of htmlentities() in
 966  * i18n environment.
 967  *
 968  * @param string $string string that has to be sanitized
 969  * @param integer $quote_style quote encoding style. Possible values (without quotes):
 970  *              <ul>
 971  *                <li>ENT_COMPAT - (default) encode double quotes</li>
 972  *                <li>ENT_NOQUOTES - don't encode double or single quotes</li>
 973  *                <li>ENT_QUOTES - encode double and single quotes</li>
 974  *              </ul>
 975  * @param string $charset charset used for encoding. defaults to 'us-ascii', 'auto' uses $default_charset global value.
 976  * @return string sanitized string
 977  * @since 1.5.1
 978  */
 979 function sq_htmlentities($string,$quote_style=ENT_COMPAT,$charset='us-ascii') {
 980   // get translation table
 981   $sq_html_ent_table=sq_get_html_translation_table(HTML_ENTITIES,$quote_style,$charset);
 982   // convert characters
 983   return str_replace(array_keys($sq_html_ent_table),array_values($sq_html_ent_table),$string);
 984 }
 985
 986 /**
 987  * Tests if string contains 8bit symbols.
 988  *
 989  * If charset is not set, function defaults to default_charset.
 990  * $default_charset global must be set correctly if $charset is
 991  * not used.
 992  * @param string $string tested string
 993  * @param string $charset charset used in a string
 994  * @return bool true if 8bit symbols are detected
 995  * @since 1.5.1 and 1.4.4
 996  */
 997 function sq_is8bit($string,$charset='') {
 998     global $default_charset;
 999
1000     if ($charset=='') $charset=$default_charset;
1001
1002     /**
1003      * Don't use \240 in ranges. Sometimes RH 7.2 doesn't like it.
1004      * Don't use \200-\237 for iso-8859-x charsets. This range
1005      * stores control symbols in those charsets.
1006      * Use preg_match instead of ereg in order to avoid problems
1007      * with mbstring overloading
1008      */
1009     if (preg_match("/^iso-8859/i",$charset)) {
1010         $needle='/\240|[\241-\377]/';
1011     } else {
1012         $needle='/[\200-\237]|\240|[\241-\377]/';
1013     }
1014     return preg_match("$needle",$string);
1015 }
1016
1017 /**
1018  * Replacement of mb_list_encodings function
1019  *
1020  * This function provides replacement for function that is available only
1021  * in php 5.x. Function does not test all mbstring encodings. Only the ones
1022  * that might be used in SM translations.
1023  *
1024  * Supported strings are stored in session in order to reduce number of
1025  * mb_internal_encoding function calls.
1026  *
1027  * If you want to test all mbstring encodings - fill $list_of_encodings
1028  * array.
1029  * @return array list of encodings supported by php mbstring extension
1030  * @since 1.5.1 and 1.4.6
1031  */
1032 function sq_mb_list_encodings() {
1033     if (! function_exists('mb_internal_encoding'))
1034         return array();
1035
1036     // php 5+ function
1037     if (function_exists('mb_list_encodings')) {
1038         $ret = mb_list_encodings();
1039         array_walk($ret,'sq_lowercase_array_vals');
1040         return $ret;
1041     }
1042
1043     // don't try to test encodings, if they are already stored in session
1044     if (sqgetGlobalVar('mb_supported_encodings',$mb_supported_encodings,SQ_SESSION))
1045         return $mb_supported_encodings;
1046
1047     // save original encoding
1048     $orig_encoding=mb_internal_encoding();
1049
1050     $list_of_encoding=array(
1051         'pass',
1052         'auto',
1053         'ascii',
1054         'jis',
1055         'utf-8',
1056         'sjis',
1057         'euc-jp',
1058         'iso-8859-1',
1059         'iso-8859-2',
1060         'iso-8859-7',
1061         'iso-8859-9',
1062         'iso-8859-15',
1063         'koi8-r',
1064         'koi8-u',
1065         'big5',
1066         'gb2312',
1067         'gb18030',
1068         'windows-1251',
1069         'windows-1255',
1070         'windows-1256',
1071         'tis-620',
1072         'iso-2022-jp',
1073         'euc-cn',
1074         'euc-kr',
1075         'euc-tw',
1076         'uhc',
1077         'utf7-imap');
1078
1079     $supported_encodings=array();
1080
1081     foreach ($list_of_encoding as $encoding) {
1082         // try setting encodings. suppress warning messages
1083         if (@mb_internal_encoding($encoding))
1084             $supported_encodings[]=$encoding;
1085     }
1086
1087     // restore original encoding
1088     mb_internal_encoding($orig_encoding);
1089
1090     // register list in session
1091     sqsession_register($supported_encodings,'mb_supported_encodings');
1092
1093     return $supported_encodings;
1094 }
1095
1096 /**
1097  * Callback function used to lowercase array values.
1098  * @param string $val array value
1099  * @param mixed $key array key
1100  * @since 1.5.1 and 1.4.6
1101  */
1102 function sq_lowercase_array_vals(&$val,$key) {
1103     $val = strtolower($val);
1104 }
1105
1106
1107 /**
1108  * Function returns number of characters in string.
1109  *
1110  * Returned number might be different from number of bytes in string,
1111  * if $charset is multibyte charset. Detection depends on mbstring
1112  * functions. If mbstring does not support tested multibyte charset,
1113  * vanilla string length function is used.
1114  * @param string $str string
1115  * @param string $charset charset
1116  * @since 1.5.1 and 1.4.6
1117  * @return integer number of characters in string
1118  */
1119 function sq_strlen($str, $charset=null){
1120     // default option
1121     if (is_null($charset)) return strlen($str);
1122
1123     // lowercase charset name
1124     $charset=strtolower($charset);
1125
1126     // use automatic charset detection, if function call asks for it
1127     if ($charset=='auto') {
1128         global $default_charset, $squirrelmail_language;
1129         set_my_charset();
1130         $charset=$default_charset;
1131         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1132     }
1133
1134     // Use mbstring only with listed charsets
1135     $aList_of_mb_charsets=array('utf-8','big5','gb2312','gb18030','euc-jp','euc-cn','euc-tw','euc-kr');
1136
1137     // calculate string length according to charset
1138     if (in_array($charset,$aList_of_mb_charsets) && in_array($charset,sq_mb_list_encodings())) {
1139         $real_length = mb_strlen($str,$charset);
1140     } else {
1141         // own strlen detection code is removed because missing strpos,
1142         // strtoupper and substr implementations break string wrapping.
1143         $real_length=strlen($str);
1144     }
1145     return $real_length;
1146 }
1147
1148 /**
1149  * string padding with multibyte support
1150  *
1151  * @link http://www.php.net/str_pad
1152  * @param string $string original string
1153  * @param integer $width padded string width
1154  * @param string $pad padding symbols
1155  * @param integer $padtype padding type
1156  *  (internal php defines, see str_pad() description)
1157  * @param string $charset charset used in original string
1158  * @return string padded string
1159  */
1160 function sq_str_pad($string, $width, $pad, $padtype, $charset='') {
1161
1162     $charset = strtolower($charset);
1163     $padded_string = '';
1164
1165     switch ($charset) {
1166     case 'utf-8':
1167     case 'big5':
1168     case 'gb2312':
1169     case 'euc-kr':
1170         /*
1171          * all multibyte charsets try to increase width value by
1172          * adding difference between number of bytes and real length
1173          */
1174         $width = $width - sq_strlen($string,$charset) + strlen($string);
1175     default:
1176         $padded_string=str_pad($string,$width,$pad,$padtype);
1177     }
1178     return $padded_string;
1179 }
1180
1181 /**
1182  * Wrapper that is used to switch between vanilla and multibyte substr
1183  * functions.
1184  * @param string $string
1185  * @param integer $start
1186  * @param integer $length
1187  * @param string $charset
1188  * @return string
1189  * @since 1.5.1
1190  * @link http://www.php.net/substr
1191  * @link http://www.php.net/mb_substr
1192  */
1193 function sq_substr($string,$start,$length,$charset='auto') {
1194     // use automatic charset detection, if function call asks for it
1195     if ($charset=='auto') {
1196         global $default_charset, $squirrelmail_language;
1197         set_my_charset();
1198         $charset=$default_charset;
1199         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1200     }
1201     $charset = strtolower($charset);
1202     if (function_exists('mb_internal_encoding') &&
1203         in_array($charset,sq_mb_list_encodings())) {
1204         return mb_substr($string,$start,$length,$charset);
1205     }
1206     // TODO: add mbstring independent code
1207
1208     // use vanilla string functions as last option
1209     return substr($string,$start,$length);
1210 }
1211
1212 /**
1213  * Wrapper that is used to switch between vanilla and multibyte strpos
1214  * functions.
1215  * @param string $haystack
1216  * @param mixed $needle
1217  * @param integer $offset
1218  * @param string $charset
1219  * @return string
1220  * @since 1.5.1
1221  * @link http://www.php.net/strpos
1222  * @link http://www.php.net/mb_strpos
1223  */
1224 function sq_strpos($haystack,$needle,$offset,$charset='auto') {
1225     // use automatic charset detection, if function call asks for it
1226     if ($charset=='auto') {
1227         global $default_charset, $squirrelmail_language;
1228         set_my_charset();
1229         $charset=$default_charset;
1230         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1231     }
1232     $charset = strtolower($charset);
1233     if (function_exists('mb_internal_encoding') &&
1234         in_array($charset,sq_mb_list_encodings())) {
1235         return mb_strpos($haystack,$needle,$offset,$charset);
1236     }
1237     // TODO: add mbstring independent code
1238
1239     // use vanilla string functions as last option
1240     return strpos($haystack,$needle,$offset);
1241 }
1242
1243 /**
1244  * Wrapper that is used to switch between vanilla and multibyte strtoupper
1245  * functions.
1246  * @param string $string
1247  * @param string $charset
1248  * @return string
1249  * @since 1.5.1
1250  * @link http://www.php.net/strtoupper
1251  * @link http://www.php.net/mb_strtoupper
1252  */
1253 function sq_strtoupper($string,$charset='auto') {
1254     // use automatic charset detection, if function call asks for it
1255     if ($charset=='auto') {
1256         global $default_charset,$squirrelmail_language;
1257         set_my_charset();
1258         $charset=$default_charset;
1259         if ($squirrelmail_language=='ja_JP') $charset='euc-jp';
1260     }
1261     $charset = strtolower($charset);
1262     if (function_exists('mb_strtoupper') &&
1263         in_array($charset,sq_mb_list_encodings())) {
1264         return mb_strtoupper($string,$charset);
1265     }
1266     // TODO: add mbstring independent code
1267
1268     // use vanilla string functions as last option
1269     return strtoupper($string);
1270 }
1271
1272 /**
1273  * Counts 8bit bytes in string
1274  * @param string $string tested string
1275  * @return integer number of 8bit bytes
1276  */
1277 function sq_count8bit($string) {
1278     $count=0;
1279     for ($i=0; $i<strlen($string); $i++) {
1280         if (ord($string[$i]) > 127) $count++;
1281     }
1282     return $count;
1283 }
1284
1285 /**
1286  * Callback function to trim whitespace from a value, to be used in array_walk
1287  * @param string $value value to trim
1288  * @since 1.5.2 and 1.4.7
1289  */
1290 function sq_trim_value ( &$value ) {
1291     $value = trim($value);
1292 }