libraries/string.lib.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  * Specialized String Functions for phpMyAdmin
   5  *
   6  * Copyright 2002 Robin Johnson <robbat2@users.sourceforge.net>
   7  * http://www.orbis-terrarum.net/?l=people.robbat2
   8  *
   9  * Defines a set of function callbacks that have a pure C version available if
  10  * the "ctype" extension is available, but otherwise have PHP versions to use
  11  * (that are slower).
  12  *
  13  * The SQL Parser code relies heavily on these functions.
  14  *
  15  * @version $Id$
  16  * @uses    extension_loaded()
  17  * @uses    substr()
  18  * @uses    function_exists()
  19  * @uses    mb_internal_encoding()
  20  * @uses    defined()
  21  * @todo a .lib filename should not have code in main(), split or rename file
  22  */
  23 if (! defined('PHPMYADMIN')) {
  24     exit;
  25 }
  26
  27 $GLOBALS['PMA_allow_mbstr'] = @function_exists('mb_strlen');
  28
  29 if ($GLOBALS['PMA_allow_mbstr']) {
  30     mb_internal_encoding($GLOBALS['charset']);
  31 }
  32
  33 // This is for handling input better
  34 if (defined('PMA_MULTIBYTE_ENCODING') || $GLOBALS['PMA_allow_mbstr']) {
  35     $GLOBALS['PMA_strpos']      = 'mb_strpos';
  36     $GLOBALS['PMA_substr']      = 'mb_substr';
  37     $GLOBALS['PMA_STR_isAlnum'] = 'ctype_alnum';
  38     $GLOBALS['PMA_STR_isDigit'] = 'ctype_digit';
  39     $GLOBALS['PMA_STR_isSpace'] = 'ctype_space';
  40     require './libraries/string_mb.lib.php';
  41 } else {
  42     $GLOBALS['PMA_strpos']      = 'strpos';
  43     $GLOBALS['PMA_substr']      = 'substr';
  44     $GLOBALS['PMA_STR_isAlnum'] = 'PMA_STR_isAlnum';
  45     $GLOBALS['PMA_STR_isDigit'] = 'PMA_STR_isDigit';
  46     $GLOBALS['PMA_STR_isSpace'] = 'PMA_STR_isSpace';
  47     require './libraries/string_native.lib.php';
  48 }
  49
  50 if (@extension_loaded('ctype')) {
  51     require './libraries/string_type_ctype.lib.php';
  52 } else {
  53     require './libraries/string_type_native.lib.php';
  54 }
  55
  56 /**
  57  * Checks if a given character position in the string is escaped or not
  58  *
  59  * @uses    PMA_strlen()
  60  * @uses    PMA_substr()
  61  * @uses    max()
  62  * @uses    intval()
  63  * @param   string   string to check for
  64  * @param   integer  the character to check for
  65  * @param   integer  starting position in the string
  66  * @return  boolean  whether the character is escaped or not
  67  */
  68 function PMA_STR_charIsEscaped($string, $pos, $start = 0)
  69 {
  70     $pos = max(intval($pos), 0);
  71     $start = max(intval($start), 0);
  72     $len = PMA_strlen($string);
  73     // Base case:
  74     // Check for string length or invalid input or special case of input
  75     // (pos == $start)
  76     if ($pos <= $start || $len <= max($pos, $start)) {
  77         return false;
  78     }
  79
  80     $pos--;
  81     $escaped     = false;
  82     while ($pos >= $start && PMA_substr($string, $pos, 1) == '\\') {
  83         $escaped = !$escaped;
  84         $pos--;
  85     } // end while
  86
  87     return $escaped;
  88 } // end of the "PMA_STR_charIsEscaped()" function
  89
  90
  91 /**
  92  * Checks if a number is in a range
  93  *
  94  * @param   integer  number to check for
  95  * @param   integer  lower bound
  96  * @param   integer  upper bound
  97  * @return  boolean  whether the number is in the range or not
  98  */
  99 function PMA_STR_numberInRangeInclusive($num, $lower, $upper)
 100 {
 101     return ($num >= $lower && $num <= $upper);
 102 } // end of the "PMA_STR_numberInRangeInclusive()" function
 103
 104 /**
 105  * Checks if a character is an SQL identifier
 106  *
 107  * @uses    PMA_STR_isAlnum()
 108  * @param   string   character to check for
 109  * @param   boolean  whether the dot character is valid or not
 110  * @return  boolean  whether the character is an SQL identifier or not
 111  */
 112 function PMA_STR_isSqlIdentifier($c, $dot_is_valid = false)
 113 {
 114     return ($GLOBALS['PMA_STR_isAlnum']($c)
 115         || ($ord_c = ord($c)) && $ord_c >= 192 && $ord_c != 215 && $ord_c != 249
 116         || $c == '_'
 117         || $c == '$'
 118         || ($dot_is_valid != false && $c == '.'));
 119 } // end of the "PMA_STR_isSqlIdentifier()" function
 120
 121
 122 /**
 123  * Binary search of a value in a sorted array
 124  *
 125  * $arr MUST be sorted, due to binary search
 126  *
 127  * @param   string   string to search for
 128  * @param   array    sorted array to search into
 129  * @param   integer  size of sorted array to search into
 130  *
 131  * @return  boolean  whether the string has been found or not
 132  */
 133 function PMA_STR_binarySearchInArr($str, $arr, $arrsize)
 134 {
 135     $top    = $arrsize - 1;
 136     $bottom = 0;
 137     $found  = false;
 138
 139     while ($top >= $bottom && $found == false) {
 140         $mid        = intval(($top + $bottom) / 2);
 141         $res        = strcmp($str, $arr[$mid]);
 142         if ($res == 0) {
 143             $found  = true;
 144         } elseif ($res < 0) {
 145             $top    = $mid - 1;
 146         } else {
 147             $bottom = $mid + 1;
 148         }
 149     } // end while
 150
 151     return $found;
 152 } // end of the "PMA_STR_binarySearchInArr()" function
 153
 154 ?>