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  * @version $Id$
  13  * @package phpMyAdmin
  14  */
  15
  16 /**
  17  * This function be used eventually to support more modes.  It is needed
  18  * because both header and footer functions must know what each other is
  19  * doing.
  20  *
  21  * @uses    $cfg['OBGzip']
  22  * @uses    function_exists()
  23  * @uses    ini_get()
  24  * @uses    ob_get_level()
  25  * @staticvar integer remember last calculated value
  26  * @return  integer  the output buffer mode
  27  */
  28 function PMA_outBufferModeGet()
  29 {
  30     static $mode = null;
  31
  32     if (null !== $mode) {
  33         return $mode;
  34     }
  35
  36     $mode = 0;
  37
  38     if ($GLOBALS['cfg']['OBGzip'] && function_exists('ob_start')) {
  39         if (ini_get('output_handler') == 'ob_gzhandler') {
  40             // If a user sets the output_handler in php.ini to ob_gzhandler, then
  41             // any right frame file in phpMyAdmin will not be handled properly by
  42             // the browser. My fix was to check the ini file within the
  43             // PMA_outBufferModeGet() function.
  44             //
  45             // (Patch by Garth Gillespie, modified by Marc Delisle)
  46             $mode = 0;
  47         } elseif (function_exists('ob_get_level') && ob_get_level() > 0) {
  48             // If output buffering is enabled in php.ini it's not possible to
  49             // add the ob_gzhandler without a warning message from php 4.3.0.
  50             // Being better safe than sorry, check for any existing output handler
  51             // instead of just checking the 'output_buffering' setting.
  52             $mode = 0;
  53         } else {
  54             $mode = 1;
  55         }
  56     }
  57
  58     // Zero (0) is no mode or in other words output buffering is OFF.
  59     // Follow 2^0, 2^1, 2^2, 2^3 type values for the modes.
  60     // Usefull if we ever decide to combine modes.  Then a bitmask field of
  61     // the sum of all modes will be the natural choice.
  62
  63     return $mode;
  64 } // end of the 'PMA_outBufferModeGet()' function
  65
  66
  67 /**
  68  * This function will need to run at the top of all pages if output
  69  * output buffering is turned on.  It also needs to be passed $mode from
  70  * the PMA_outBufferModeGet() function or it will be useless.
  71  *
  72  * @uses    PMA_outBufferModeGet()
  73  * @uses    PMA_outBufferPost() to register it as shutdown function
  74  * @uses    ob_start()
  75  * @uses    header() to send X-ob_mode:
  76  * @uses    register_shutdown_function() to register PMA_outBufferPost()
  77  */
  78 function PMA_outBufferPre()
  79 {
  80     if ($mode = PMA_outBufferModeGet()) {
  81         ob_start('ob_gzhandler');
  82     }
  83
  84     header('X-ob_mode: ' . $mode);
  85
  86     register_shutdown_function('PMA_outBufferPost');
  87 } // end of the 'PMA_outBufferPre()' function
  88
  89
  90 /**
  91  * This function will need to run at the bottom of all pages if output
  92  * buffering is turned on.  It also needs to be passed $mode from the
  93  * PMA_outBufferModeGet() function or it will be useless.
  94  *
  95  * @uses    PMA_outBufferModeGet()
  96  * @uses    ob_flush()
  97  * @uses    flush()
  98  */
  99 function PMA_outBufferPost()
 100 {
 101     if (ob_get_status() && PMA_outBufferModeGet()) {
 102         ob_flush();
 103     }
 104     /**
 105      * previously we had here an "else flush()" but some PHP versions
 106      * (at least PHP 5.2.11) have a bug (49816) that produces garbled
 107      * data
 108      */
 109 } // end of the 'PMA_outBufferPost()' function
 110
 111 ?>