Code Changes

	$db->sql_transaction('commit');

	return true;
}

/**
* Delete all PM(s) for a given user and delete the ones without references
*
* @param	int		$user_id	ID of the user whose private messages we want to delete
*
* @return	boolean		False if there were no pms found, true otherwise.
*/
function phpbb_delete_user_pms($user_id)
{
	global $db, $user, $phpbb_root_path, $phpEx;

	$user_id = (int) $user_id;

	if (!$user_id)
	{
		return false;
	}

	// Get PM Information for later deleting
	// The two queries where split, so we can use our indexes
	$undelivered_msg = $delete_ids = array();

	// Part 1: get PMs the user received
	$sql = 'SELECT msg_id
		FROM ' . PRIVMSGS_TO_TABLE . '
		WHERE user_id = ' . $user_id;
	$result = $db->sql_query($sql);

	while ($row = $db->sql_fetchrow($result))
	{
		$msg_id = (int) $row['msg_id'];
		$delete_ids[$msg_id] = $msg_id;
	}
	$db->sql_freeresult($result);

	// Part 2: get PMs the user sent, but have yet to be received
	// We cannot simply delete them. First we have to check,
	// whether another user already received and read the message.
	$sql = 'SELECT msg_id
		FROM ' . PRIVMSGS_TO_TABLE . '
		WHERE author_id = ' . $user_id . '
			AND folder_id = ' . PRIVMSGS_NO_BOX;
	$result = $db->sql_query($sql);

	while ($row = $db->sql_fetchrow($result))
	{
		$msg_id = (int) $row['msg_id'];
		$undelivered_msg[$msg_id] = $msg_id;
	}
	$db->sql_freeresult($result);

	if (empty($delete_ids) && empty($undelivered_msg))
	{
		return false;
	}

	$db->sql_transaction('begin');

	if (!empty($undelivered_msg))
	{
		// A pm is delivered, if for any recipient the message was moved
		// from their NO_BOX to another folder. We do not delete such
		// messages, but only delete them for users, who have not yet
		// received them.
		$sql = 'SELECT msg_id
			FROM ' . PRIVMSGS_TO_TABLE . '
			WHERE author_id = ' . $user_id . '
				AND folder_id <> ' . PRIVMSGS_NO_BOX . '
				AND folder_id <> ' . PRIVMSGS_OUTBOX . '
				AND folder_id <> ' . PRIVMSGS_SENTBOX;
		$result = $db->sql_query($sql);

		$delivered_msg = array();
		while ($row = $db->sql_fetchrow($result))
		{
			$msg_id = (int) $row['msg_id'];
			$delivered_msg[$msg_id] = $msg_id;
			unset($undelivered_msg[$msg_id]);
		}
		$db->sql_freeresult($result);

		$undelivered_user = array();

		// Count the messages we delete, so we can correct the user pm data
		$sql = 'SELECT user_id, COUNT(msg_id) as num_undelivered_privmsgs
			FROM ' . PRIVMSGS_TO_TABLE . '
			WHERE author_id = ' . $user_id . '
				AND folder_id = ' . PRIVMSGS_NO_BOX . '
					AND ' . $db->sql_in_set('msg_id', array_merge($undelivered_msg, $delivered_msg)) . '
			GROUP BY user_id';
		$result = $db->sql_query($sql);

		while ($row = $db->sql_fetchrow($result))
		{
			$num_pms = (int) $row['num_undelivered_privmsgs'];
			$undelivered_user[$num_pms][] = (int) $row['user_id'];

			if (sizeof($undelivered_user[$num_pms]) > 50)
			{
				// If there are too many users affected the query might get
				// too long, so we update the value for the first bunch here.
				$sql = 'UPDATE ' . USERS_TABLE . '
					SET user_new_privmsg = user_new_privmsg - ' . $num_pms . ',
						user_unread_privmsg = user_unread_privmsg - ' . $num_pms . '
					WHERE ' . $db->sql_in_set('user_id', $undelivered_user[$num_pms]);
				$db->sql_query($sql);
				unset($undelivered_user[$num_pms]);
			}
		}
		$db->sql_freeresult($result);

		foreach ($undelivered_user as $num_pms => $undelivered_user_set)
		{
			$sql = 'UPDATE ' . USERS_TABLE . '
				SET user_new_privmsg = user_new_privmsg - ' . $num_pms . ',
					user_unread_privmsg = user_unread_privmsg - ' . $num_pms . '
				WHERE ' . $db->sql_in_set('user_id', $undelivered_user_set);
			$db->sql_query($sql);
		}

		if (!empty($delivered_msg))
		{
			$sql = 'DELETE FROM ' . PRIVMSGS_TO_TABLE . '
				WHERE folder_id = ' . PRIVMSGS_NO_BOX . '
					AND ' . $db->sql_in_set('msg_id', $delivered_msg);
			$db->sql_query($sql);
		}

		if (!empty($undelivered_msg))
		{
			$sql = 'DELETE FROM ' . PRIVMSGS_TO_TABLE . '
				WHERE ' . $db->sql_in_set('msg_id', $undelivered_msg);
			$db->sql_query($sql);

			$sql = 'DELETE FROM ' . PRIVMSGS_TABLE . '
				WHERE ' . $db->sql_in_set('msg_id', $undelivered_msg);
			$db->sql_query($sql);
		}
	}

	// Reset the user's pm count to 0
	$sql = 'UPDATE ' . USERS_TABLE . '
		SET user_new_privmsg = 0,
			user_unread_privmsg = 0
		WHERE user_id = ' . $user_id;
	$db->sql_query($sql);

	// Delete private message data of the user
	$sql = 'DELETE FROM ' . PRIVMSGS_TO_TABLE . '
		WHERE user_id = ' . (int) $user_id;
	$db->sql_query($sql);

	if (!empty($delete_ids))
	{
		// Now we have to check which messages we can delete completely
		$sql = 'SELECT msg_id
			FROM ' . PRIVMSGS_TO_TABLE . '
			WHERE ' . $db->sql_in_set('msg_id', $delete_ids);
		$result = $db->sql_query($sql);

		while ($row = $db->sql_fetchrow($result))
		{
			unset($delete_ids[$row['msg_id']]);
		}
		$db->sql_freeresult($result);

		if (!empty($delete_ids))
		{
			// Check if there are any attachments we need to remove
			if (!function_exists('delete_attachments'))
			{
				include($phpbb_root_path . 'includes/functions_admin.' . $phpEx);
			}

			delete_attachments('message', $delete_ids, false);

			$sql = 'DELETE FROM ' . PRIVMSGS_TABLE . '
				WHERE ' . $db->sql_in_set('msg_id', $delete_ids);
			$db->sql_query($sql);
		}
	}

	// Set the remaining author id to anonymous
	// This way users are still able to read messages from users being removed
	$sql = 'UPDATE ' . PRIVMSGS_TO_TABLE . '
		SET author_id = ' . ANONYMOUS . '
		WHERE author_id = ' . $user_id;
	$db->sql_query($sql);

	$sql = 'UPDATE ' . PRIVMSGS_TABLE . '
		SET author_id = ' . ANONYMOUS . '
		WHERE author_id = ' . $user_id;
	$db->sql_query($sql);

	// Exclude guests, current user and banned users from notifications