libraries/ob.lib.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  * Output buffer functions for phpMyAdmin
   5  *
   6  * Copyright 2001 Jeremy Brand <jeremy@nirvani.net>
   7  * http://www.jeremybrand.com/Jeremy/Brand/Jeremy_Brand.html
   8  *
   9  * Check for all the needed functions for output buffering
  10  * Make some wrappers for the top and bottoms of our files.
  11  *
  12  * @package phpMyAdmin
  13  */
  14
  15 /**
  16  * This function be used eventually to support more modes.  It is needed
  17  * because both header and footer functions must know what each other is
  18  * doing.
  19  *
  20  * @uses    $cfg['OBGzip']
  21  * @uses    function_exists()
  22  * @uses    ini_get()
  23  * @uses    ob_get_level()
  24  * @staticvar integer remember last calculated value
  25  * @return  integer  the output buffer mode
  26  */
  27 function PMA_outBufferModeGet()
  28 {
  29     static $mode = null;
  30
  31     if (null !== $mode) {
  32         return $mode;
  33     }
  34
  35     $mode = 0;
  36
  37     if ($GLOBALS['cfg']['OBGzip'] && function_exists('ob_start')) {
  38         if (ini_get('output_handler') == 'ob_gzhandler') {
  39             // If a user sets the output_handler in php.ini to ob_gzhandler, then
  40             // any right frame file in phpMyAdmin will not be handled properly by
  41             // the browser. My fix was to check the ini file within the
  42             // PMA_outBufferModeGet() function.
  43             $mode = 0;
  44         } elseif (function_exists('ob_get_level') && ob_get_level() > 0) {
  45             // If output buffering is enabled in php.ini it's not possible to
  46             // add the ob_gzhandler without a warning message from php 4.3.0.
  47             // Being better safe than sorry, check for any existing output handler
  48             // instead of just checking the 'output_buffering' setting.
  49             $mode = 0;
  50         } else {
  51             $mode = 1;
  52         }
  53     }
  54
  55     // Zero (0) is no mode or in other words output buffering is OFF.
  56     // Follow 2^0, 2^1, 2^2, 2^3 type values for the modes.
  57     // Usefull if we ever decide to combine modes.  Then a bitmask field of
  58     // the sum of all modes will be the natural choice.
  59
  60     return $mode;
  61 } // end of the 'PMA_outBufferModeGet()' function
  62
  63
  64 /**
  65  * This function will need to run at the top of all pages if output
  66  * output buffering is turned on.  It also needs to be passed $mode from
  67  * the PMA_outBufferModeGet() function or it will be useless.
  68  *
  69  * @uses    PMA_outBufferModeGet()
  70  * @uses    PMA_outBufferPost() to register it as shutdown function
  71  * @uses    ob_start()
  72  * @uses    header() to send X-ob_mode:
  73  * @uses    register_shutdown_function() to register PMA_outBufferPost()
  74  */
  75 function PMA_outBufferPre()
  76 {
  77     if ($mode = PMA_outBufferModeGet()) {
  78         ob_start('ob_gzhandler');
  79     }
  80
  81     header('X-ob_mode: ' . $mode);
  82
  83     register_shutdown_function('PMA_outBufferPost');
  84 } // end of the 'PMA_outBufferPre()' function
  85
  86
  87 /**
  88  * This function will need to run at the bottom of all pages if output
  89  * buffering is turned on.  It also needs to be passed $mode from the
  90  * PMA_outBufferModeGet() function or it will be useless.
  91  *
  92  * @uses    PMA_outBufferModeGet()
  93  * @uses    ob_flush()
  94  * @uses    flush()
  95  */
  96 function PMA_outBufferPost()
  97 {
  98     if (ob_get_status() && PMA_outBufferModeGet()) {
  99         ob_flush();
 100     }
 101     /**
 102      * previously we had here an "else flush()" but some PHP versions
 103      * (at least PHP 5.2.11) have a bug (49816) that produces garbled
 104      * data
 105      */
 106 } // end of the 'PMA_outBufferPost()' function
 107
 108 ?>