Add upstream

wp-content/plugins/jetpack/modules/sitemaps/sitemap-buffer-page.php

@@ -0,0 +1,67 @@
+<?php
+/**
+ * Sitemaps (per the protocol) are essentially lists of XML fragments;
+ * lists which are subject to size constraints. The Jetpack_Sitemap_Buffer_Page
+ * extends the Jetpack_Sitemap_Buffer class to represent the single page sitemap
+ * buffer.
+ *
+ * @since 5.3.0
+ * @package Jetpack
+ */
+
+/**
+ * A buffer for constructing sitemap page xml files.
+ *
+ * @since 5.3.0
+ */
+class Jetpack_Sitemap_Buffer_Page extends Jetpack_Sitemap_Buffer {
+
+	public function __construct( $item_limit, $byte_limit, $time = '1970-01-01 00:00:00' ) {
+		parent::__construct( $item_limit, $byte_limit, $time );
+
+		$this->doc->appendChild(
+			$this->doc->createComment( "generator='jetpack-" . JETPACK__VERSION . "'" )
+		);
+
+		$this->doc->appendChild(
+			$this->doc->createProcessingInstruction(
+				'xml-stylesheet',
+				'type="text/xsl" href="' . $this->finder->construct_sitemap_url( 'sitemap.xsl' ) . '"'
+			)
+		);
+	}
+
+	protected function get_root_element() {
+		if ( ! isset( $this->root ) ) {
+
+			/**
+			 * Filter the attribute value pairs used for namespace and namespace URI mappings.
+			 *
+			 * @module sitemaps
+			 *
+			 * @since 3.9.0
+			 *
+			 * @param array $namespaces Associative array with namespaces and namespace URIs.
+			 */
+			$namespaces = apply_filters(
+				'jetpack_sitemap_ns',
+				array(
+					'xmlns:xsi'          => 'http://www.w3.org/2001/XMLSchema-instance',
+					'xsi:schemaLocation' => 'http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd',
+					'xmlns'              => 'http://www.sitemaps.org/schemas/sitemap/0.9',
+				)
+			);
+
+			$this->root = $this->doc->createElement( 'urlset' );
+
+			foreach ( $namespaces as $name => $value ) {
+				$this->root->setAttribute( $name, $value );
+			}
+
+			$this->doc->appendChild( $this->root );
+			$this->byte_capacity -= strlen( $this->doc->saveXML( $this->root ) );
+		}
+
+		return $this->root;
+	}
+}