xml: add support for 3.0 xml format

For now, it only changes the XML header to <topology version="3.0">

We still use hwloc2.dtd, we'll fork it later into a hwloc3.dtd if needed.

2.0 is still enabled internally for now,
but 2.0 and 3.0 import/export is supported.

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>

NEWS

@@ -43,6 +43,9 @@ Version 3.0.0
     - hwloc_cpuset_from_nodeset_strict()
   + HWLOC_PCI_<domain>_<bus>_LOCALCPUS environment variables,
     superseded with a single HWLOC_PCI_LOCALITY since 2.0.
+* Misc
+  + XML format switches to 3.0 by default. Exporting to 2.x is
+    possible with the new V2 XML export flag.
 
 
 Version 2.9.0

hwloc/topology-xml-libxml.c

@@ -1,6 +1,6 @@
 /*
  * Copyright © 2009 CNRS
- * Copyright © 2009-2018 Inria.  All rights reserved.
+ * Copyright © 2009-2022 Inria.  All rights reserved.
  * Copyright © 2009-2011, 2020 Université Bordeaux
  * Copyright © 2009-2011 Cisco Systems, Inc.  All rights reserved.
  * See COPYING in top-level directory.
@@ -438,6 +438,7 @@ hwloc__libxml2_prepare_export(hwloc_topology_t topology, struct hwloc__xml_expor
   struct hwloc__xml_export_state_s state;
   hwloc__libxml_export_state_data_t data = (void *) state.data;
   int v1export = flags & HWLOC_TOPOLOGY_EXPORT_XML_FLAG_V1;
+  int v2export = flags & HWLOC_TOPOLOGY_EXPORT_XML_FLAG_V2;
   xmlDocPtr doc = NULL;       /* document pointer */
   xmlNodePtr root_node = NULL; /* root pointer */
 
@@ -449,8 +450,12 @@ hwloc__libxml2_prepare_export(hwloc_topology_t topology, struct hwloc__xml_expor
   /* Creates a new document, a node and set it as a root node. */
   doc = xmlNewDoc(BAD_CAST "1.0");
   root_node = xmlNewNode(NULL, BAD_CAST "topology");
-  if (!(flags & HWLOC_TOPOLOGY_EXPORT_XML_FLAG_V1))
-    xmlNewProp(root_node, BAD_CAST "version", BAD_CAST "2.0");
+  if (!v1export) {
+    if (v2export)
+      xmlNewProp(root_node, BAD_CAST "version", BAD_CAST "2.0");
+    else
+      xmlNewProp(root_node, BAD_CAST "version", BAD_CAST "3.0");
+  }
   xmlDocSetRootElement(doc, root_node);
 
   /* Creates a DTD declaration. Isn't mandatory. */

hwloc/topology-xml-nolibxml.c

@@ -1,6 +1,6 @@
 /*
  * Copyright © 2009 CNRS
- * Copyright © 2009-2020 Inria.  All rights reserved.
+ * Copyright © 2009-2022 Inria.  All rights reserved.
  * Copyright © 2009-2011 Université Bordeaux
  * Copyright © 2009-2011 Cisco Systems, Inc.  All rights reserved.
  * See COPYING in top-level directory.
@@ -676,6 +676,7 @@ hwloc___nolibxml_prepare_export(hwloc_topology_t topology, struct hwloc__xml_exp
   struct hwloc__xml_export_state_s state, childstate;
   hwloc__nolibxml_export_state_data_t ndata = (void *) &state.data;
   int v1export = flags & HWLOC_TOPOLOGY_EXPORT_XML_FLAG_V1;
+  int v2export = flags & HWLOC_TOPOLOGY_EXPORT_XML_FLAG_V2;
   int res;
 
   HWLOC_BUILD_ASSERT(sizeof(*ndata) <= sizeof(state.data));
@@ -699,8 +700,12 @@ hwloc___nolibxml_prepare_export(hwloc_topology_t topology, struct hwloc__xml_exp
 		 "<!DOCTYPE topology SYSTEM \"%s\">\n", v1export ? "hwloc.dtd" : "hwloc2.dtd");
   hwloc__nolibxml_export_update_buffer(ndata, res);
   hwloc__nolibxml_export_new_child(&state, &childstate, "topology");
-  if (!(flags & HWLOC_TOPOLOGY_EXPORT_XML_FLAG_V1))
-    hwloc__nolibxml_export_new_prop(&childstate, "version", "2.0");
+  if (!v1export) {
+    if (v2export)
+      hwloc__nolibxml_export_new_prop(&childstate, "version", "2.0");
+    else
+      hwloc__nolibxml_export_new_prop(&childstate, "version", "3.0");
+  }
   hwloc__xml_export_topology (&childstate, topology, flags);
   hwloc__nolibxml_export_end_object(&childstate, "topology");
 

hwloc/topology-xml.c

@@ -2081,7 +2081,7 @@ hwloc_look_xml(struct hwloc_backend *backend, struct hwloc_disc_status *dstatus)
   if (ret < 0)
     goto failed;
 
-  if (data->version_major > 2) {
+  if (data->version_major > 3) {
     if (hwloc__xml_verbose())
       fprintf(stderr, "%s: cannot import XML version %u.%u > 2\n",
 	      data->msgprefix, data->version_major, data->version_minor);

utils/lstopo/lstopo-no-graphics.1in

@@ -69,7 +69,7 @@ Enforce flags when exporting to the XML format.
 Flags may be given as numeric values or as a comma-separated list of flag names
 that are passed to \fIhwloc_topology_export_xml()\fR.
 Those names may be substrings of actual flag names as long as a single one matches.
-A value of \fB1\fR (or \fBv1\fR) reverts to the format of hwloc v1.x.
+A value of \fB2\fR (or \fBv2\fR) reverts to the format of hwloc v2.x.
 The default is \fB0\fR (or \fBnone\fR).
 .TP
 \fB\-\-export\-synthetic\-flags\fR <flags>