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 $GLOBALS['PMA_allow_ctype'] = @extension_loaded('ctype');
  29
  30 if ($GLOBALS['PMA_allow_mbstr']) {
  31     mb_internal_encoding($GLOBALS['charset']);
  32 }
  33
  34 // This is for handling input better
  35 if (defined('PMA_MULTIBYTE_ENCODING') || $GLOBALS['PMA_allow_mbstr']) {
  36     $GLOBALS['PMA_strpos']      = 'mb_strpos';
  37     $GLOBALS['PMA_substr']      = 'mb_substr';
  38     require './libraries/string_mb.lib.php';
  39 } else {
  40     $GLOBALS['PMA_strpos']      = 'strpos';
  41     $GLOBALS['PMA_substr']      = 'substr';
  42     require './libraries/string_native.lib.php';
  43 }
  44
  45 if ($GLOBALS['PMA_allow_ctype']) {
  46     $GLOBALS['PMA_STR_isAlnum'] = 'ctype_alnum';
  47     $GLOBALS['PMA_STR_isDigit'] = 'ctype_digit';
  48     $GLOBALS['PMA_STR_isSpace'] = 'ctype_space';
  49     require './libraries/string_type_ctype.lib.php';
  50 } else {
  51     $GLOBALS['PMA_STR_isAlnum'] = 'PMA_STR_isAlnum';
  52     $GLOBALS['PMA_STR_isDigit'] = 'PMA_STR_isDigit';
  53     $GLOBALS['PMA_STR_isSpace'] = 'PMA_STR_isSpace';
  54     require './libraries/string_type_native.lib.php';
  55 }
  56
  57 /**
  58  * Checks if a given character position in the string is escaped or not
  59  *
  60  * @uses    PMA_strlen()
  61  * @uses    PMA_substr()
  62  * @uses    max()
  63  * @uses    intval()
  64  * @param   string   string to check for
  65  * @param   integer  the character to check for
  66  * @param   integer  starting position in the string
  67  * @return  boolean  whether the character is escaped or not
  68  */
  69 function PMA_STR_charIsEscaped($string, $pos, $start = 0)
  70 {
  71     $pos = max(intval($pos), 0);
  72     $start = max(intval($start), 0);
  73     $len = PMA_strlen($string);
  74     // Base case:
  75     // Check for string length or invalid input or special case of input
  76     // (pos == $start)
  77     if ($pos <= $start || $len <= max($pos, $start)) {
  78         return false;
  79     }
  80
  81     $pos--;
  82     $escaped     = false;
  83     while ($pos >= $start && PMA_substr($string, $pos, 1) == '\\') {
  84         $escaped = !$escaped;
  85         $pos--;
  86     } // end while
  87
  88     return $escaped;
  89 } // end of the "PMA_STR_charIsEscaped()" function
  90
  91
  92 /**
  93  * Checks if a number is in a range
  94  *
  95  * @param   integer  number to check for
  96  * @param   integer  lower bound
  97  * @param   integer  upper bound
  98  * @return  boolean  whether the number is in the range or not
  99  */
 100 function PMA_STR_numberInRangeInclusive($num, $lower, $upper)
 101 {
 102     return ($num >= $lower && $num <= $upper);
 103 } // end of the "PMA_STR_numberInRangeInclusive()" function
 104
 105 /**
 106  * Checks if a character is an SQL identifier
 107  *
 108  * @uses    PMA_STR_isAlnum()
 109  * @param   string   character to check for
 110  * @param   boolean  whether the dot character is valid or not
 111  * @return  boolean  whether the character is an SQL identifier or not
 112  */
 113 function PMA_STR_isSqlIdentifier($c, $dot_is_valid = false)
 114 {
 115     return ($GLOBALS['PMA_STR_isAlnum']($c)
 116         || ($ord_c = ord($c)) && $ord_c >= 192 && $ord_c != 215 && $ord_c != 249
 117         || $c == '_'
 118         || $c == '$'
 119         || ($dot_is_valid != false && $c == '.'));
 120 } // end of the "PMA_STR_isSqlIdentifier()" function
 121
 122
 123 /**
 124  * Binary search of a value in a sorted array
 125  *
 126  * $arr MUST be sorted, due to binary search
 127  *
 128  * @param   string   string to search for
 129  * @param   array    sorted array to search into
 130  * @param   integer  size of sorted array to search into
 131  *
 132  * @return  boolean  whether the string has been found or not
 133  */
 134 function PMA_STR_binarySearchInArr($str, $arr, $arrsize)
 135 {
 136     $top    = $arrsize - 1;
 137     $bottom = 0;
 138     $found  = false;
 139
 140     while ($top >= $bottom && $found == false) {
 141         $mid        = intval(($top + $bottom) / 2);
 142         $res        = strcmp($str, $arr[$mid]);
 143         if ($res == 0) {
 144             $found  = true;
 145         } elseif ($res < 0) {
 146             $top    = $mid - 1;
 147         } else {
 148             $bottom = $mid + 1;
 149         }
 150     } // end while
 151
 152     return $found;
 153 } // end of the "PMA_STR_binarySearchInArr()" function
 154
 155 ?>