From cd1228df78eb15ae9ce226417e4d7a709571ddf6 Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov@git.wordpress.org>
Date: Mon, 20 Feb 2023 16:03:17 +0000
Subject: [PATCH] Bootstrap/Load: Check that either `mysqli_connect()` or
 `mysql_connect()` is available.

This resolves a fatal error and displays an actionable message if the `mysqli` PHP extension is missing.

Previously, `wp_check_php_mysql_versions()` performed an early check whether `mysql`, `mysqli`, or `mysqlnd` extensions are loaded, but that did not work if the `mysqlnd` extension is the only one present.

Checking specifically for `mysqli_connect()` or `mysql_connect()` functions should be a more reliable approach and more closely mirrors the existing checks in the `wpdb` class.

Follow-up to [1955], [4489], [7234], [12732], [19760], [27257], [36434].

Props bgin, desrosj, dimadin, ipajen, hellofromTonya, sc0ttkclark, azaozz, SergeyBiryukov.
Fixes #51988.

git-svn-id: https://develop.svn.wordpress.org/trunk@55367 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/load.php | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/src/wp-includes/load.php b/src/wp-includes/load.php
index c2450e582f..533155b987 100644
--- a/src/wp-includes/load.php
+++ b/src/wp-includes/load.php
@@ -149,23 +149,43 @@ function wp_check_php_mysql_versions() {
 		$protocol = wp_get_server_protocol();
 		header( sprintf( '%s 500 Internal Server Error', $protocol ), true, 500 );
 		header( 'Content-Type: text/html; charset=utf-8' );
-		printf( 'Your server is running PHP version %1$s but WordPress %2$s requires at least %3$s.', $php_version, $wp_version, $required_php_version );
+		printf(
+			'Your server is running PHP version %1$s but WordPress %2$s requires at least %3$s.',
+			$php_version,
+			$wp_version,
+			$required_php_version
+		);
 		exit( 1 );
 	}
 
-	if ( ! extension_loaded( 'mysql' ) && ! extension_loaded( 'mysqli' ) && ! extension_loaded( 'mysqlnd' )
+	if ( ! function_exists( 'mysqli_connect' ) && ! function_exists( 'mysql_connect' )
 		// This runs before default constants are defined, so we can't assume WP_CONTENT_DIR is set yet.
 		&& ( defined( 'WP_CONTENT_DIR' ) && ! file_exists( WP_CONTENT_DIR . '/db.php' )
 			|| ! file_exists( ABSPATH . 'wp-content/db.php' ) )
 	) {
 		require_once ABSPATH . WPINC . '/functions.php';
 		wp_load_translations_early();
+
+		$message = '<p>' . __( 'Your PHP installation appears to be missing the MySQL extension which is required by WordPress.' ) . "</p>\n";
+
+		$message .= '<p>' . sprintf(
+			/* translators: %s: mysqli. */
+			__( 'Please check that the %s PHP extension is installed and enabled.' ),
+			'<code>mysqli</code>'
+		) . "</p>\n";
+
+		$message .= '<p>' . sprintf(
+			/* translators: %s: Support forums URL. */
+			__( 'If you are unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href="%s">WordPress Support Forums</a>.' ),
+			__( 'https://wordpress.org/support/forums/' )
+		) . "</p>\n";
+
 		$args = array(
 			'exit' => false,
 			'code' => 'mysql_not_found',
 		);
 		wp_die(
-			__( 'Your PHP installation appears to be missing the MySQL extension which is required by WordPress.' ),
+			$message,
 			__( 'Requirements Not Met' ),
 			$args
 		);