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  * @uses    extension_loaded()
  16  * @uses    substr()
  17  * @uses    function_exists()
  18  * @uses    mb_internal_encoding()
  19  * @uses    defined()
  20  * @todo a .lib filename should not have code in main(), split or rename file
  21  * @package phpMyAdmin
  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 /**
  35  * Load proper code for handling input.
  36  */
  37 if (defined('PMA_MULTIBYTE_ENCODING') || $GLOBALS['PMA_allow_mbstr']) {
  38     $GLOBALS['PMA_strpos']      = 'mb_strpos';
  39     $GLOBALS['PMA_substr']      = 'mb_substr';
  40     require './libraries/string_mb.lib.php';
  41 } else {
  42     $GLOBALS['PMA_strpos']      = 'strpos';
  43     $GLOBALS['PMA_substr']      = 'substr';
  44     require './libraries/string_native.lib.php';
  45 }
  46
  47 /**
  48  * Load ctype handler.
  49  */
  50 if ($GLOBALS['PMA_allow_ctype']) {
  51     $GLOBALS['PMA_STR_isAlnum'] = 'ctype_alnum';
  52     $GLOBALS['PMA_STR_isDigit'] = 'ctype_digit';
  53     $GLOBALS['PMA_STR_isSpace'] = 'ctype_space';
  54     require './libraries/string_type_ctype.lib.php';
  55 } else {
  56     $GLOBALS['PMA_STR_isAlnum'] = 'PMA_STR_isAlnum';
  57     $GLOBALS['PMA_STR_isDigit'] = 'PMA_STR_isDigit';
  58     $GLOBALS['PMA_STR_isSpace'] = 'PMA_STR_isSpace';
  59     require './libraries/string_type_native.lib.php';
  60 }
  61
  62 /**
  63  * Checks if a given character position in the string is escaped or not
  64  *
  65  * @uses    PMA_strlen()
  66  * @uses    PMA_substr()
  67  * @uses    max()
  68  * @uses    intval()
  69  * @param   string   string to check for
  70  * @param   integer  the character to check for
  71  * @param   integer  starting position in the string
  72  * @return  boolean  whether the character is escaped or not
  73  */
  74 function PMA_STR_charIsEscaped($string, $pos, $start = 0)
  75 {
  76     $pos = max(intval($pos), 0);
  77     $start = max(intval($start), 0);
  78     $len = PMA_strlen($string);
  79     // Base case:
  80     // Check for string length or invalid input or special case of input
  81     // (pos == $start)
  82     if ($pos <= $start || $len <= max($pos, $start)) {
  83         return false;
  84     }
  85
  86     $pos--;
  87     $escaped     = false;
  88     while ($pos >= $start && PMA_substr($string, $pos, 1) == '\\') {
  89         $escaped = !$escaped;
  90         $pos--;
  91     } // end while
  92
  93     return $escaped;
  94 } // end of the "PMA_STR_charIsEscaped()" function
  95
  96
  97 /**
  98  * Checks if a number is in a range
  99  *
 100  * @param   integer  number to check for
 101  * @param   integer  lower bound
 102  * @param   integer  upper bound
 103  * @return  boolean  whether the number is in the range or not
 104  */
 105 function PMA_STR_numberInRangeInclusive($num, $lower, $upper)
 106 {
 107     return ($num >= $lower && $num <= $upper);
 108 } // end of the "PMA_STR_numberInRangeInclusive()" function
 109
 110 /**
 111  * Checks if a character is an SQL identifier
 112  *
 113  * @uses    PMA_STR_isAlnum()
 114  * @param   string   character to check for
 115  * @param   boolean  whether the dot character is valid or not
 116  * @return  boolean  whether the character is an SQL identifier or not
 117  */
 118 function PMA_STR_isSqlIdentifier($c, $dot_is_valid = false)
 119 {
 120     return ($GLOBALS['PMA_STR_isAlnum']($c)
 121         || ($ord_c = ord($c)) && $ord_c >= 192 && $ord_c != 215 && $ord_c != 249
 122         || $c == '_'
 123         || $c == '$'
 124         || ($dot_is_valid != false && $c == '.'));
 125 } // end of the "PMA_STR_isSqlIdentifier()" function
 126
 127
 128 /**
 129  * Binary search of a value in a sorted array
 130  *
 131  * $arr MUST be sorted, due to binary search
 132  *
 133  * @param   string   string to search for
 134  * @param   array    sorted array to search into
 135  * @param   integer  size of sorted array to search into
 136  *
 137  * @return  boolean  whether the string has been found or not
 138  */
 139 function PMA_STR_binarySearchInArr($str, $arr, $arrsize)
 140 {
 141     $top    = $arrsize - 1;
 142     $bottom = 0;
 143     $found  = false;
 144
 145     while ($top >= $bottom && $found == false) {
 146         $mid        = intval(($top + $bottom) / 2);
 147         $res        = strcmp($str, $arr[$mid]);
 148         if ($res == 0) {
 149             $found  = true;
 150         } elseif ($res < 0) {
 151             $top    = $mid - 1;
 152         } else {
 153             $bottom = $mid + 1;
 154         }
 155     } // end while
 156
 157     return $found;
 158 } // end of the "PMA_STR_binarySearchInArr()" function
 159
 160 ?>