bp_blogs_post_pre_publish( bool $return = true, int $blog_id, int $post_id, int $user_id )

function bp_blogs_post_pre_publish( $return = true, $blog_id = 0, $post_id = 0, $user_id = 0 ) {
	$bp = buddypress();

	// If blog is not trackable, do not record the activity.
	if ( ! bp_blogs_is_blog_trackable( $blog_id, $user_id ) ) {
		return false;
	}

	/*
	 * Stop infinite loops with WordPress MU Sitewide Tags.
	 * That plugin changed the way its settings were stored at some point. Thus the dual check.
	 */
	$sitewide_tags_blog_settings = bp_core_get_root_option( 'sitewide_tags_blog' );
	if ( ! empty( $sitewide_tags_blog_settings ) ) {
		$st_options = maybe_unserialize( $sitewide_tags_blog_settings );
		$tags_blog_id = isset( $st_options['tags_blog_id'] ) ? $st_options['tags_blog_id'] : 0;
	} else {
		$tags_blog_id = bp_core_get_root_option( 'sitewide_tags_blog' );
		$tags_blog_id = intval( $tags_blog_id );
	}

	/**
	 * Filters whether or not BuddyPress should block sitewide tags activity.
	 *
	 * @since BuddyPress 2.2.0
	 *
	 * @param bool $value Current status of the sitewide tags activity.
	 */
	if ( (int) $blog_id == $tags_blog_id && apply_filters( 'bp_blogs_block_sitewide_tags_activity', true ) ) {
		return false;
	}

	/**
	 * Filters whether or not the current blog is public.
	 *
	 * @since BuddyPress 2.2.0
	 *
	 * @param int $value Value from the blog_public option for the current blog.
	 */
	$is_blog_public = apply_filters( 'bp_is_blog_public', (int) get_blog_option( $blog_id, 'blog_public' ) );

	if ( 0 === $is_blog_public && is_multisite() ) {
		return false;
	}

	return $return;
}