From 952830b5290de9176336bd8d938389a8fcd4e15b Mon Sep 17 00:00:00 2001
From: Andy Miller <rhuk@mac.com>
Date: Thu, 25 Dec 2025 21:17:22 -0700
Subject: [PATCH] fix gzip encoding issue with newer PHP 8 versions

Signed-off-by: Andy Miller <rhuk@mac.com>
---
 system/src/Grav/Common/Grav.php               | 32 ++++++++++---------
 .../Common/Processors/InitializeProcessor.php |  8 +++--
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/system/src/Grav/Common/Grav.php b/system/src/Grav/Common/Grav.php
index 3ad09ba2f..d73b803f3 100644
--- a/system/src/Grav/Common/Grav.php
+++ b/system/src/Grav/Common/Grav.php
@@ -608,23 +608,25 @@ class Grav extends Container
                 // Unfortunately without FastCGI there is no way to force close the connection.
                 // We need to ask browser to close the connection for us.
 
-                if ($config->get('system.cache.gzip')) {
-                    // Flush gzhandler buffer if gzip setting was enabled to get the size of the compressed output.
-                    ob_end_flush();
-                } elseif ($config->get('system.cache.allow_webserver_gzip')) {
-                    // Let web server to do the hard work.
-                    header('Content-Encoding: identity');
-                } elseif (function_exists('apache_setenv')) {
-                    // Without gzip we have no other choice than to prevent server from compressing the output.
-                    // This action turns off mod_deflate which would prevent us from closing the connection.
-                    @apache_setenv('no-gzip', '1');
-                } else {
-                    // Fall back to unknown content encoding, it prevents most servers from deflating the content.
-                    header('Content-Encoding: none');
+                // With zlib.output_compression enabled, PHP handles compression automatically.
+                // We cannot set Content-Length when compression is active (size unknown until compressed).
+                if (!$config->get('system.cache.gzip') && !ini_get('zlib.output_compression')) {
+                    if ($config->get('system.cache.allow_webserver_gzip')) {
+                        // Let web server to do the hard work.
+                        header('Content-Encoding: identity');
+                    } elseif (function_exists('apache_setenv')) {
+                        // Without gzip we have no other choice than to prevent server from compressing the output.
+                        // This action turns off mod_deflate which would prevent us from closing the connection.
+                        @apache_setenv('no-gzip', '1');
+                    } else {
+                        // Fall back to unknown content encoding, it prevents most servers from deflating the content.
+                        header('Content-Encoding: none');
+                    }
+
+                    // Get length and close the connection (only when not using compression).
+                    header('Content-Length: ' . ob_get_length());
                 }
 
-                // Get length and close the connection.
-                header('Content-Length: ' . ob_get_length());
                 header('Connection: close');
 
                 ob_end_flush();
diff --git a/system/src/Grav/Common/Processors/InitializeProcessor.php b/system/src/Grav/Common/Processors/InitializeProcessor.php
index af8d59711..70620f300 100644
--- a/system/src/Grav/Common/Processors/InitializeProcessor.php
+++ b/system/src/Grav/Common/Processors/InitializeProcessor.php
@@ -345,9 +345,11 @@ class InitializeProcessor extends ProcessorBase
 
         // Use output buffering to prevent headers from being sent too early.
         ob_start();
-        if ($config->get('system.cache.gzip') && !@ob_start('ob_gzhandler')) {
-            // Enable zip/deflate with a fallback in case of if browser does not support compressing.
-            ob_start();
+        if ($config->get('system.cache.gzip')) {
+            // Try to use zlib.output_compression instead of ob_gzhandler (more robust)
+            if (!ini_get('zlib.output_compression') && !headers_sent()) {
+                ini_set('zlib.output_compression', '4096');
+            }
         }
 
         $this->stopTimer('_init_ob');