presence_reginfo: Add option for aggregating presentities

src/modules/presence_reginfo/Makefile

@@ -8,6 +8,25 @@ include ../../Makefile.defs
 auto_gen=
 NAME=presence_reginfo.so
 
+ifeq ($(CROSS_COMPILE),)
+XML2CFG=$(shell which xml2-config)
+ifeq ($(XML2CFG),)
+XML2CFG=$(shell \
+	if pkg-config --exists libxml-2.0; then \
+		echo 'pkg-config libxml-2.0'; \
+	fi)
+endif
+endif
+
+ifneq ($(XML2CFG),)
+	DEFS += $(shell $(XML2CFG) --cflags )
+	LIBS += $(shell $(XML2CFG) --libs)
+else
+	DEFS+=-I$(LOCALBASE)/include/libxml2 \
+		-I$(LOCALBASE)/include
+	LIBS+=-L$(LOCALBASE)/lib -lxml2
+endif
+
 include ../../Makefile.modules
 
 

src/modules/presence_reginfo/add_events.c

@@ -27,6 +27,9 @@
 #include "../../core/parser/parse_content.h"
 #include "../presence/event_list.h"
 #include "presence_reginfo.h"
+#include "notify_body.h"
+
+extern int pres_reginfo_aggregate_presentities;
 
 int reginfo_add_events(void)
 {
@@ -39,12 +42,22 @@ int reginfo_add_events(void)
 
 	event.content_type.s = "application/reginfo+xml";
 	event.content_type.len = 23;
-	event.default_expires= pres_reginfo_default_expires;
+	event.default_expires = pres_reginfo_default_expires;
 	event.type = PUBL_TYPE;
 	event.req_auth = 0;
 	event.evs_publ_handl = 0;
 
-	if (pres_add_event(&event) < 0) {
+
+	if(pres_reginfo_aggregate_presentities) {
+		/* aggregate XML body and free() fuction */
+		event.agg_nbody = reginfo_agg_nbody;
+		event.free_body = free_xml_body;
+		/* modify XML body for each watcher to set the correct "version" */
+		event.aux_body_processing = reginfo_body_setversion;
+		event.aux_free_body = free_xml_body;
+	}
+
+	if(pres_add_event(&event) < 0) {
 		LM_ERR("failed to add event \"reginfo\"\n");
 		return -1;
 	}

src/modules/presence_reginfo/doc/presence_reginfo_admin.xml

@@ -86,6 +86,27 @@
             </example>
         </section>
 
+				<section id="presence_reginfo.p.aggregate_presentities">
+							<title><varname>aggregate_presentities</varname> (int)</title>
+							<para>
+							Whether to aggregate in a single notify body all registration 
+							presentities. Useful to have all registrations on first NOTIFY
+							following initial SUBSCRIBE.
+							</para>
+							<para>
+							<emphasis>Default value is <quote>0</quote> (disabled).
+							</emphasis>
+							</para>
+							<example>
+							<title>Set <varname>aggregate_presentities</varname> parameter</title>
+							<programlisting format="linespecific">
+					...
+					modparam("presence_reginfo", "aggregate_presentities", 1)
+					...
+					</programlisting>
+							</example>
+					</section>
+
 	</section>
 
 

src/modules/presence_reginfo/notify_body.c

@@ -0,0 +1,314 @@
+/*
+ * presence_dialoginfo module
+ *
+ * Copyright (C) 2006 Voice Sistem S.R.L.
+ * Copyright (C) 2008 Klaus Darilion, IPCom
+ * Copyright (C) 2022 Matteo Brancaleoni, VoiSmart
+ *
+ * This file is part of Kamailio, a free SIP server.
+ *
+ * Kamailio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version
+ *
+ * Kamailio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+/*! \file
+ * \brief Kamailio Presence_reginfo :: Notify BODY handling
+ * \ingroup presence_reginfo
+ */
+
+#define MAX_INT_LEN 11 /* 2^32: 10 chars + 1 char sign */
+
+#include <string.h>
+#include <stdlib.h>
+#include <libxml/parser.h>
+
+#include "../../core/mem/mem.h"
+#include "../presence/hash.h"
+#include "../presence/presence.h"
+
+
+str *agregate_xmls(str *pres_user, str *pres_domain, str **body_array, int n);
+
+void free_xml_body(char *body)
+{
+	if(body == NULL)
+		return;
+
+	xmlFree(body);
+	body = NULL;
+}
+
+str *reginfo_agg_nbody(str *pres_user, str *pres_domain, str **body_array,
+		int n, int off_index)
+{
+	str *n_body = NULL;
+
+	LM_DBG("[pres_user]=%.*s [pres_domain]= %.*s, [n]=%d\n", pres_user->len,
+			pres_user->s, pres_domain->len, pres_domain->s, n);
+
+	if(body_array == NULL) {
+		return NULL;
+	}
+
+	n_body = agregate_xmls(pres_user, pres_domain, body_array, n);
+	LM_DBG("[n_body]=%p\n", n_body);
+	if(n_body) {
+		LM_DBG("[*n_body]=%.*s\n", n_body->len, n_body->s);
+	}
+	if(n_body == NULL && n != 0) {
+		LM_ERR("while aggregating body\n");
+	}
+
+	xmlCleanupParser();
+	xmlMemoryDump();
+
+	return n_body;
+}
+
+str *agregate_xmls(str *pres_user, str *pres_domain, str **body_array, int n)
+{
+	int i, j = 0;
+
+	str *body = NULL;
+
+	xmlDocPtr doc = NULL;
+	xmlNodePtr root_node = NULL;
+	xmlNsPtr namespace = NULL;
+	xmlNodePtr p_root = NULL;
+	xmlDocPtr *xml_array;
+	xmlNodePtr node = NULL;
+	xmlNodePtr next_node = NULL;
+
+	LM_DBG("[pres_user]=%.*s [pres_domain]= %.*s, [n]=%d\n", pres_user->len,
+			pres_user->s, pres_domain->len, pres_domain->s, n);
+
+	xml_array = (xmlDocPtr *)pkg_malloc(n * sizeof(xmlDocPtr));
+	if(xml_array == NULL) {
+		PKG_MEM_ERROR;
+		return NULL;
+	}
+	memset(xml_array, 0, n * sizeof(xmlDocPtr));
+
+	/* parse all the XML documents into xml_array[] */
+	for(i = 0; i < n; i++) {
+		if(body_array[i] == NULL)
+			continue;
+
+		xml_array[j] = NULL;
+		xml_array[j] = xmlParseMemory(body_array[i]->s, body_array[i]->len);
+		if(xml_array[j] == NULL) {
+			LM_ERR("while parsing xml body message\n");
+			goto error;
+		}
+		j++;
+	}
+
+	if(j == 0) /* no body */
+	{
+		LM_DBG("no body to be built\n");
+		goto error;
+	}
+
+	/* n: number of bodies in total */
+	/* j: number of useful bodies; created XML structures */
+	/* i: loop counter */
+
+	/* create the new NOTIFY body  */
+	doc = xmlNewDoc(BAD_CAST "1.0");
+	if(doc == 0) {
+		LM_ERR("unable to create xml document\n");
+		goto error;
+	}
+
+	root_node = xmlNewNode(NULL, BAD_CAST "reginfo");
+	if(root_node == 0) {
+		goto error;
+	}
+
+	xmlDocSetRootElement(doc, root_node);
+	namespace = xmlNewNs(
+			root_node, BAD_CAST "urn:ietf:params:xml:ns:reginfo", NULL);
+	if(!namespace) {
+		LM_ERR("creating namespace failed\n");
+	}
+	xmlSetNs(root_node, namespace);
+
+	/* The version must be increased for each new document and is a 32bit int.
+	 * As the version is different for each watcher, we can not set here the
+	 * correct value. Thus, we just put here a placeholder which will be
+	 * replaced by the correct value in the aux_body_processing callback.
+	 * Thus we have CPU intensive XML aggregation only once and can use
+	 * quick search&replace in the per-watcher aux_body_processing callback.
+	 * We use 11 chracters as an signed int (although RFC says unsigned int we
+	 * use signed int as presence module stores "version" in DB as
+	 * signed int) has max. 10 characters + 1 character for the sign
+	 */
+	xmlNewProp(root_node, BAD_CAST "version", BAD_CAST "00000000000");
+	xmlNewProp(root_node, BAD_CAST "state", BAD_CAST "full");
+
+	/* loop over all bodies and create the aggregated body */
+	for(i = 0; i < j; i++) {
+		// get the root reginfo element
+		p_root = xmlDocGetRootElement(xml_array[i]);
+		if(p_root == NULL) {
+			LM_ERR("the xml_tree root element is null\n");
+			goto error;
+		}
+
+		// get the children registration elements
+		if(p_root->children) {
+			// loop over registration elements
+			for(node = p_root->children; node; node = next_node) {
+				next_node = node->next;
+				if(node->type != XML_ELEMENT_NODE) {
+					continue;
+				}
+				LM_DBG("node type: Element, name: %s\n", node->name);
+
+				/* we do not copy the node, but unlink it and then add it ot the new node
+				 * this destroys the original document but we do not need it anyway.
+				 */
+				xmlUnlinkNode(node);
+				if(xmlAddChild(root_node, node) == NULL) {
+					xmlFreeNode(node);
+					LM_ERR("while adding child\n");
+					goto error;
+				}
+			} // end of loop over registration elements
+		}
+	} // end of loop over all bodies
+
+	// convert to string & cleanup
+	body = (str *)pkg_malloc(sizeof(str));
+	if(body == NULL) {
+		ERR_MEM(PKG_MEM_STR);
+	}
+
+	xmlDocDumpFormatMemory(doc, (xmlChar **)(void *)&body->s, &body->len, 1);
+
+	for(i = 0; i < j; i++) {
+		if(xml_array[i] != NULL)
+			xmlFreeDoc(xml_array[i]);
+	}
+	if(doc) {
+		xmlFreeDoc(doc);
+	}
+	if(xml_array)
+		pkg_free(xml_array);
+
+	xmlCleanupParser();
+	xmlMemoryDump();
+
+	return body;
+
+	// error handling, cleanup and return NULL
+error:
+	if(xml_array != NULL) {
+		for(i = 0; i < j; i++) {
+			if(xml_array[i] != NULL)
+				xmlFreeDoc(xml_array[i]);
+		}
+		pkg_free(xml_array);
+	}
+	if(body) {
+		pkg_free(body);
+	}
+	if(doc) {
+		xmlFreeDoc(doc);
+	}
+
+	return NULL;
+}
+
+str *reginfo_body_setversion(subs_t *subs, str *body)
+{
+	char *version_start = 0;
+	char version[MAX_INT_LEN + 2]; /* +2 becasue of trailing " and \0 */
+	int version_len;
+	str *aux_body = NULL;
+
+	if(!body) {
+		return NULL;
+	}
+
+	/* xmlDocDumpFormatMemory creates \0 terminated string */
+	/* version parameters starts at minimum at character 30 */
+	if(body->len < 37) {
+		LM_ERR("body string too short!\n");
+		return NULL;
+	}
+	version_start = strstr(body->s + 30, "version=");
+	if(!version_start) {
+		LM_ERR("version string not found!\n");
+		return NULL;
+	}
+	version_start += 9;
+
+	/* safety check for placeholder - if it is body not set by the module,
+	 * don't update the version */
+	if(strncmp(version_start, "00000000000\"", 12) != 0)
+		return NULL;
+
+	version_len = snprintf(version, MAX_INT_LEN + 2, "%d\"", subs->version);
+	if(version_len >= MAX_INT_LEN + 2) {
+		LM_ERR("failed to convert 'version' to string (truncated output)\n");
+		return NULL;
+	} else if(version_len < 0) {
+		LM_ERR("failed to convert 'version' to string (encoding error)\n");
+		return NULL;
+	}
+
+	aux_body = (str *)pkg_malloc(sizeof(str));
+	if(aux_body == NULL) {
+		PKG_MEM_ERROR_FMT("error allocating memory for aux body str\n");
+		return NULL;
+	}
+	memset(aux_body, 0, sizeof(str));
+	aux_body->s = (char *)pkg_malloc(body->len * sizeof(char));
+	if(aux_body->s == NULL) {
+		pkg_free(aux_body);
+		PKG_MEM_ERROR_FMT("error allocating memory for aux body buffer\n");
+		return NULL;
+	}
+	memcpy(aux_body->s, body->s, body->len);
+	aux_body->len = body->len;
+
+	/* again but on the copied str, no checks needed */
+	version_start = strstr(aux_body->s + 30, "version=");
+	version_start += 9;
+	/* Replace the placeholder 00000000000 with the version.
+	 * Put the padding behind the ""
+	 */
+	LM_DBG("replace version with \"%s\n", version);
+	memcpy(version_start, version, version_len);
+	memset(version_start + version_len, ' ', 12 - version_len);
+
+	xmlDocPtr doc =
+			xmlReadMemory(aux_body->s, aux_body->len, "noname.xml", NULL, 0);
+	if(doc == NULL) {
+		LM_ERR("error allocation xmldoc\n");
+		pkg_free(aux_body->s);
+		pkg_free(aux_body);
+		return NULL;
+	}
+	pkg_free(aux_body->s);
+	xmlDocDumpFormatMemory(
+			doc, (xmlChar **)(void *)&aux_body->s, &aux_body->len, 1);
+	xmlFreeDoc(doc);
+	xmlCleanupParser();
+	xmlMemoryDump();
+
+	return aux_body;
+}

src/modules/presence_reginfo/notify_body.h

@@ -0,0 +1,43 @@
+/*
+ * presence_dialoginfo module
+ *
+ * Copyright (C) 2006 Voice Sistem S.R.L.
+ * Copyright (C) 2008 Klaus Darilion, IPCom
+ * Copyright (C) 2022 Matteo Brancaleoni, VoiSmart
+ *
+ * This file is part of Kamailio, a free SIP server.
+ *
+ * Kamailio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version
+ *
+ * Kamailio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+/*! \file
+ * \brief Kamailio presence reginfo  ::
+ * \ref notify_body.c
+ * \ingroup presence_reginfo
+ */
+
+
+#ifndef _NBODY_H_
+#define _NBODY_H_
+
+str *reginfo_agg_nbody(str *pres_user, str *pres_domain, str **body_array,
+		int n, int off_index);
+
+str *reginfo_body_setversion(subs_t *subs, str *body);
+
+void free_xml_body(char *body);
+
+#endif

src/modules/presence_reginfo/presence_reginfo.c

@@ -47,11 +47,13 @@ static int mod_init(void);
 add_event_t pres_add_event;
 
 /* module parameters */
+int pres_reginfo_aggregate_presentities = 0;
 unsigned int pres_reginfo_default_expires = 3600;
 
 /* module exported paramaters */
 static param_export_t params[] = {
 	{ "default_expires", INT_PARAM, &pres_reginfo_default_expires },
+	{ "aggregate_presentities", INT_PARAM, &pres_reginfo_aggregate_presentities },
 	{0, 0, 0}
 };
 
@@ -89,6 +91,12 @@ static int mod_init(void)
 		return -1;
 	}
 
+	if (pres_reginfo_aggregate_presentities != 0
+			&& pres_reginfo_aggregate_presentities != 1) {
+		LM_ERR("invalid aggregate_presentities param value, should be 0 or 1\n");
+		return -1;
+	}
+
 	pres_add_event = pres.add_event;
 	if (pres_add_event == NULL) {
 		LM_ERR("could not import add_event\n");