Drop remaining MySQL <5.5.3 support (utf8 without multibyte)

It's over 10 years out-of-date and EOL and the version code isn't failsafe which causes issues with some MariaDB versions, resulting in broken multibyte character behaviors.

inc/database.php

@@ -78,10 +78,7 @@ function sql_open() {
 		if ($config['debug'])
 			$debug['time']['db_connect'] = '~' . round((microtime(true) - $start) * 1000, 2) . 'ms';
 		
-		if (mysql_version() >= 50503)
-			query('SET NAMES utf8mb4') or error(db_error());
-		else
-			query('SET NAMES utf8') or error(db_error());
+		query('SET NAMES utf8mb4') or error(db_error());
 		return $pdo;
 	} catch(PDOException $e) {
 		$message = $e->getMessage();
@@ -95,17 +92,6 @@ function sql_open() {
 	}
 }
 
-// 5.6.10 becomes 50610
-function mysql_version() {
-	global $pdo;
-	
-	$version = $pdo->getAttribute(PDO::ATTR_SERVER_VERSION);
-	$v = explode('.', $version);
-	if (count($v) != 3)
-		return false;
-	return (int) sprintf("%02d%02d%02d", $v[0], $v[1], $v[2]);
-}
-
 function prepare($query) {
 	global $pdo, $debug, $config;
 	

inc/functions.php

@@ -2445,9 +2445,6 @@ function markup(&$body, $track_cites = false, $op = false) {
 	$body = str_replace("\r", '', $body);
 	$body = utf8tohtml($body);
 
-	if (mysql_version() < 50503)
-		$body = mb_encode_numericentity($body, array(0x010000, 0xffffff, 0, 0xffffff), 'UTF-8');
-
 	if ($config['markup_code']) {
 		$code_markup = array();
 		$body = preg_replace_callback($config['markup_code'], function($matches) use (&$code_markup) {

inc/mod/pages.php

@@ -502,9 +502,6 @@ function mod_new_board() {
 		
 		$query = Element('posts.sql', array('board' => $board['uri']));
 		
-		if (mysql_version() < 50503)
-			$query = preg_replace('/(CHARSET=|CHARACTER SET )utf8mb4/', '$1utf8', $query);
-		
 		query($query) or error(db_error());
 
 		// Create shadow copy table

install.php

@@ -68,10 +68,7 @@ if (file_exists($config['has_installed'])) {
 	function __query($sql) {
 		sql_open();
 		
-		if (mysql_version() >= 50503)
-			return query($sql);
-		else
-			return query(str_replace('utf8mb4', 'utf8', $sql));
+		return query($sql);
 	}
 	
 	$boards = listBoards();
@@ -1118,7 +1115,6 @@ if ($step == 0) {
 	$sql = @file_get_contents('install.sql') or error("Couldn't load install.sql.");
 	
 	sql_open();
-	$mysql_version = mysql_version();
 	
 	// This code is probably horrible, but what I'm trying
 	// to do is find all of the SQL queires and put them
@@ -1130,8 +1126,6 @@ if ($step == 0) {
 	
 	$sql_errors = '';
 	foreach ($queries as $query) {
-		if ($mysql_version < 50503)
-			$query = preg_replace('/(CHARSET=|CHARACTER SET )utf8mb4/', '$1utf8', $query);
 		$query = preg_replace('/^([\w\s]*)`([0-9a-zA-Z$_\x{0080}-\x{FFFF}]+)`/u', '$1``$2``', $query);
 		if (!query($query))
 			$sql_errors .= '<li>' . db_error() . '</li>';

post.php

@@ -834,22 +834,7 @@ if (isset($_POST['delete'])) {
 		$post['body'] .= "\n<tinyboard proxy>".$proxy."</tinyboard>";
 	}
 	
-	if (mysql_version() >= 50503) {
-		$post['body_nomarkup'] = $post['body']; // Assume we're using the utf8mb4 charset
-	} else {
-		// MySQL's `utf8` charset only supports up to 3-byte symbols
-		// Remove anything >= 0x010000
-		
-		$chars = preg_split('//u', $post['body'], -1, PREG_SPLIT_NO_EMPTY);
-		$post['body_nomarkup'] = '';
-		foreach ($chars as $char) {
-			$o = 0;
-			$ord = ordutf8($char, $o);
-			if ($ord >= 0x010000)
-				continue;
-			$post['body_nomarkup'] .= $char;
-		}
-	}
+	$post['body_nomarkup'] = $post['body']; // Assume we're using the utf8mb4 charset
 	
 	$post['tracked_cites'] = markup($post['body'], true);