From: Aaron Bannert <aaron@php.net>
Date: Sun, 5 May 2002 18:11:41 +0000 (+0000)
Subject: Fix an elusive and intermittent startup SEGV. The problem was
X-Git-Tag: php-4.3.0dev-ZendEngine2-Preview1~218
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b759322411220e9c165776be743700b8799ffec2;p=php

Fix an elusive and intermittent startup SEGV. The problem was
the static string we were using to set an initialization flag
would get remapped to a different location when Apache reloaded
the DSO, causing us to not run our initialization routines.

Submitted by: Justin Erenkrantz <jerenkrantz@apache.org>
Reviewed by: Aaron Bannert (I added the big comment too)
---

diff --git a/sapi/apache2filter/sapi_apache2.c b/sapi/apache2filter/sapi_apache2.c
index e512a89e8f..81f3fd6d0e 100644
--- a/sapi/apache2filter/sapi_apache2.c
+++ b/sapi/apache2filter/sapi_apache2.c
@@ -454,14 +454,19 @@ php_apache_server_startup(apr_pool_t *pconf, apr_pool_t *plog,
 	 * prevents us from starting PHP until the second load. */
 	apr_pool_userdata_get(&data, userdata_key, s->process->pool);
 	if (data == NULL) {
-		apr_pool_userdata_setn((const void *)1, userdata_key,
-							   apr_pool_cleanup_null, s->process->pool);
+		/* We must use set() here and *not* setn(), otherwise the
+		 * static string pointed to by userdata_key will be mapped
+		 * to a different location when the DSO is reloaded and the
+		 * pointers won't match, causing get() to return NULL when
+		 * we expected it to return non-NULL. */
+		apr_pool_userdata_set((const void *)1, userdata_key,
+							  apr_pool_cleanup_null, s->process->pool);
 		return OK;
 	}
 	else if (data == (const void *)2) {
 		return OK;
 	}
-	apr_pool_userdata_setn((const void *)2, userdata_key,
+	apr_pool_userdata_set((const void *)2, userdata_key,
 						   apr_pool_cleanup_null, s->process->pool);
 
 	/* Set up our overridden path. */