Problem/Motivation

Upgrade Status module reports the following PHP 8.4 deprecation problems for a D11 migration:

modules/contrib/captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php	128	Call to deprecated function lcg_value().
modules/contrib/captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php	129	Call to deprecated function lcg_value().
modules/contrib/captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php	132	Call to deprecated function lcg_value().
modules/contrib/captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php	133	Call to deprecated function lcg_value().

Steps to reproduce

Install the upgrade_status module on 10.x site with Captcha installed..
Scan the captcha module

See https://www.php.net/manual/en/function.lcg-value.php

Proposed resolution

Change the lcg_value calls to use the Random extension. E.g:

$randomizer = new Random\Randomizer();
$random_float = $randomizer->getFloat();

Note this was added in PHP 8.2. But since PHP 8.1 officially reached End of Life (EOL) on December 31, 2025 this shouldn't be a blocker.

Remaining tasks

Make changes

User interface changes

N/A

API changes

N/A

Data model changes

N/A

CommentFileSizeAuthor
#2 captcha-3570435-replace_lcg_value-2.patch1.53 KBcgmonroe

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Comments

cgmonroe created an issue. See original summary.

cgmonroe’s picture

cgmonroe commented
Status: Active » Needs review
StatusFileSize
new captcha-3570435-replace_lcg_value-2.patch1.53 KB

Here's a patch to remove the deprecated calls

anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented
Version: 2.0.9 » 2.x-dev
Status: Needs review » Needs work

@cgmonroe could you please provide this as MR, not patch? Thanks!

cgmonroe opened merge request !131

anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented
Priority: Normal » Major
Status: Needs work » Needs review
lfersoy’s picture

lfersoy commented

Patch confirmed. +1 RTBC

anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented
Issue summary: View changes
anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented

Still needs someone to set it RTBC once reviewed.

herved’s picture

herved commented

There are also other deprecations for 8.5, like imagedestroy(), but maybe that should be a followup?

------ --------------------------------------------------------------------------------------------------------------------------------------- 
  Line   captcha/captcha.install                                                                                                                
 ------ --------------------------------------------------------------------------------------------------------------------------------------- 
  119    Call to deprecated function node_type_get_names():                                                                                     
         in drupal:11.3.0 and is removed from drupal:13.0.0. Use \Drupal::service('entity_type.bundle.info')->getBundleLabels('node') instead.  
         🪪  function.deprecated                                                                                                                
 ------ --------------------------------------------------------------------------------------------------------------------------------------- 

 ------ ------------------------------------------------------- 
  Line   captcha/modules/image_captcha/image_captcha.admin.inc  
 ------ ------------------------------------------------------- 
  67     Call to deprecated function imagedestroy().            
         🪪  function.deprecated                                
 ------ ------------------------------------------------------- 

 ------ ------------------------------------------------------------------------------- 
  Line   captcha/modules/image_captcha/src/Controller/CaptchaFontPreviewController.php  
 ------ ------------------------------------------------------------------------------- 
  100    Call to deprecated function imagedestroy().                                    
         🪪  function.deprecated                                                        
 ------ ------------------------------------------------------------------------------- 

 ------ ---------------------------------------------------------------------------------- 
  Line   captcha/modules/image_captcha/src/Controller/CaptchaImageGeneratorController.php  
 ------ ---------------------------------------------------------------------------------- 
  144    Call to deprecated function imagedestroy().                                       
         🪪  function.deprecated                                                           
 ------ ---------------------------------------------------------------------------------- 

 ------ ------------------------------------------------------------------------- 
  Line   captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php  
 ------ ------------------------------------------------------------------------- 
  128    Call to deprecated function lcg_value().                                 
         🪪  function.deprecated                                                  
  129    Call to deprecated function lcg_value().                                 
         🪪  function.deprecated                                                  
  132    Call to deprecated function lcg_value().                                 
         🪪  function.deprecated                                                  
  133    Call to deprecated function lcg_value().                                 
         🪪  function.deprecated                                                  
 ------ -------------------------------------------------------------------------

 ------ ------------------------------------------------------------------------------------------ 
  Line   captcha/src/Element/Captcha.php                                                           
 ------ ------------------------------------------------------------------------------------------ 
  41     Call to method __construct() of deprecated class Drupal\Core\Render\Element\FormElement:  
         in drupal:10.3.0 and is removed from drupal:12.0.0. use                                   
           \Drupal\Core\Render\Element\FormElementBase instead.                                    
         🪪  method.deprecatedClass                                                                
 ------ ------------------------------------------------------------------------------------------
anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented

@herved yes I think let's do that separately.

csakiistvan’s picture

csakiistvan
Primary language Hungarian
Location Budapest, Hungary
commented
Status: Needs review » Reviewed & tested by the community

Environment

  • Drupal 11.3.9, PHP 8.3.30, DDEV v1.25.2
  • drupal/captcha: 2.0.10

Step 1 — Install the module

composer require drupal/captcha
ddev drush en captcha image_captcha -y

Step 2 — Enable distortion to trigger the affected code path

The lcg_value() calls only execute when image_captcha_distortion_amplitude is greater than 1:

ddev drush config:set image_captcha.settings image_captcha_distortion_amplitude 5 -y

Step 3 — Apply the fix from MR !131

In modules/image_captcha/src/Service/ImageCaptchaRenderService.php, replace the four lcg_value() calls with \Random\Randomizer:

$randomizer = new \Random\Randomizer();
$wavelength_xr = (2 + 3 * $randomizer->getFloat(0, 1)) * $font_size;
$wavelength_yr = (2 + 3 * $randomizer->getFloat(0, 1)) * $font_size;
// ...
$wavelength_xt = (2 + 3 * $randomizer->getFloat(0, 1)) * $font_size;
$wavelength_yt = (2 + 3 * $randomizer->getFloat(0, 1)) * $font_size;

Step 4 — Verify the fix

Syntax check:

ddev exec php -l web/modules/contrib/captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php

Expected: No syntax errors detected

Confirm the image endpoint returns a valid image:

curl -s -o /dev/null -w "%{http_code} %{content_type}" https://tester.ddev.site/image-captcha-generate/{session_id}/{timestamp}

Expected: 200 image/jpeg

Results

Test Result
Module installs and enables without errors ✅ Pass
All four lcg_value() calls replaced with \Random\Randomizer::getFloat() ✅ Pass
PHP syntax check passes after the change ✅ Pass
CAPTCHA image generates successfully with distortion enabled ✅ Pass

The fix works correctly. \Random\Randomizer::getFloat() is available since PHP 8.2 and is the appropriate replacement for the deprecated lcg_value().

This comment was produced with the assistance of an LLM

anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented

Thanks, merged into dev to push things forward here. Could we please have a separate follow-up for #9?

anybody’s picture

anybody
Primary language German
Location Porta Westfalica
commented
Status: Reviewed & tested by the community » Fixed

Now that this issue is closed, review the contribution record.

As a contributor, attribute any organization that helped you, or if you volunteered your own time.

Maintainers, credit people who helped resolve this issue.

Status: Fixed » Closed (fixed)

Automatically closed - issue fixed for 2 weeks with no activity.

pfrenssen’s picture

pfrenssen
Location Sofia
commented

Created followup to address #9: #3601310: Remove deprecated calls to imagedestroy()

hoporr’s picture

hoporr commented

(issue was closed, cannot reopen, so I created a second issue with this text)

Captcha 2.0.10:
Drupal core 11.3.13
PHP 8.4

1) Tried to install the MR patch, and it failed.

2) I then installed the patch from #2, and am getting this error when the captcha is supposed to be rendered (also on the image_captcha config page):

ParseError: syntax error, unexpected token ".", expecting identifier or variable or "{" or "$" in {closure:Composer\Autoload\ClassLoader::initializeIncludeClosure():575}() (Zeile 131 in /...../www/modules/contrib/captcha/modules/image_captcha/src/Service/ImageCaptchaRenderService.php).

The patch applied like this -- note the '.' in front of "getFloat" , so yes here is a problem:
$wavelength_yr = (2 + 3 * $randomizer->.getFloat(0, 1)) * $font_size;

I then inspected the actual patches, and noticed this:

patch #2 actually has the error in it, note the '.' :
+ $wavelength_yr = (2 + 3 * $randomizer->.getFloat(0, 1)) * $font_size;

In the MR, the line is correct:
+ $wavelength_yr = (2 + 3 * $randomizer->getFloat(0, 1)) * $font_size;

But the MR fails to install for me.