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 /**
  34  * Load proper code for handling input.
  35  */
  36 if (defined('PMA_MULTIBYTE_ENCODING') || $GLOBALS['PMA_allow_mbstr']) {
  37     $GLOBALS['PMA_strpos']      = 'mb_strpos';
  38     $GLOBALS['PMA_substr']      = 'mb_substr';
  39     $GLOBALS['PMA_STR_isAlnum'] = 'ctype_alnum';
  40     $GLOBALS['PMA_STR_isDigit'] = 'ctype_digit';
  41     $GLOBALS['PMA_STR_isSpace'] = 'ctype_space';
  42     require './libraries/string_mb.lib.php';
  43 } else {
  44     $GLOBALS['PMA_strpos']      = 'strpos';
  45     $GLOBALS['PMA_substr']      = 'substr';
  46     $GLOBALS['PMA_STR_isAlnum'] = 'PMA_STR_isAlnum';
  47     $GLOBALS['PMA_STR_isDigit'] = 'PMA_STR_isDigit';
  48     $GLOBALS['PMA_STR_isSpace'] = 'PMA_STR_isSpace';
  49     require './libraries/string_native.lib.php';
  50 }
  51
  52 /**
  53  * Load ctype handler.
  54  */
  55 if (@extension_loaded('ctype')) {
  56     require './libraries/string_type_ctype.lib.php';
  57 } else {
  58     require './libraries/string_type_native.lib.php';
  59 }
  60
  61 /**
  62  * Checks if a given character position in the string is escaped or not
  63  *
  64  * @uses    PMA_strlen()
  65  * @uses    PMA_substr()
  66  * @uses    max()
  67  * @uses    intval()
  68  * @param   string   string to check for
  69  * @param   integer  the character to check for
  70  * @param   integer  starting position in the string
  71  * @return  boolean  whether the character is escaped or not
  72  */
  73 function PMA_STR_charIsEscaped($string, $pos, $start = 0)
  74 {
  75     $pos = max(intval($pos), 0);
  76     $start = max(intval($start), 0);
  77     $len = PMA_strlen($string);
  78     // Base case:
  79     // Check for string length or invalid input or special case of input
  80     // (pos == $start)
  81     if ($pos <= $start || $len <= max($pos, $start)) {
  82         return false;
  83     }
  84
  85     $pos--;
  86     $escaped     = false;
  87     while ($pos >= $start && PMA_substr($string, $pos, 1) == '\\') {
  88         $escaped = !$escaped;
  89         $pos--;
  90     } // end while
  91
  92     return $escaped;
  93 } // end of the "PMA_STR_charIsEscaped()" function
  94
  95
  96 /**
  97  * Checks if a number is in a range
  98  *
  99  * @param   integer  number to check for
 100  * @param   integer  lower bound
 101  * @param   integer  upper bound
 102  * @return  boolean  whether the number is in the range or not
 103  */
 104 function PMA_STR_numberInRangeInclusive($num, $lower, $upper)
 105 {
 106     return ($num >= $lower && $num <= $upper);
 107 } // end of the "PMA_STR_numberInRangeInclusive()" function
 108
 109 /**
 110  * Checks if a character is an SQL identifier
 111  *
 112  * @uses    PMA_STR_isAlnum()
 113  * @param   string   character to check for
 114  * @param   boolean  whether the dot character is valid or not
 115  * @return  boolean  whether the character is an SQL identifier or not
 116  */
 117 function PMA_STR_isSqlIdentifier($c, $dot_is_valid = false)
 118 {
 119     return ($GLOBALS['PMA_STR_isAlnum']($c)
 120         || ($ord_c = ord($c)) && $ord_c >= 192 && $ord_c != 215 && $ord_c != 249
 121         || $c == '_'
 122         || $c == '$'
 123         || ($dot_is_valid != false && $c == '.'));
 124 } // end of the "PMA_STR_isSqlIdentifier()" function
 125
 126
 127 /**
 128  * Binary search of a value in a sorted array
 129  *
 130  * $arr MUST be sorted, due to binary search
 131  *
 132  * @param   string   string to search for
 133  * @param   array    sorted array to search into
 134  * @param   integer  size of sorted array to search into
 135  *
 136  * @return  boolean  whether the string has been found or not
 137  */
 138 function PMA_STR_binarySearchInArr($str, $arr, $arrsize)
 139 {
 140     $top    = $arrsize - 1;
 141     $bottom = 0;
 142     $found  = false;
 143
 144     while ($top >= $bottom && $found == false) {
 145         $mid        = intval(($top + $bottom) / 2);
 146         $res        = strcmp($str, $arr[$mid]);
 147         if ($res == 0) {
 148             $found  = true;
 149         } elseif ($res < 0) {
 150             $top    = $mid - 1;
 151         } else {
 152             $bottom = $mid + 1;
 153         }
 154     } // end while
 155
 156     return $found;
 157 } // end of the "PMA_STR_binarySearchInArr()" function
 158
 159 ?>