res_pjsip: Add utils for checking media types

Added two new functions to assist checking media types...

* ast_sip_are_media_types_equal compares two pjsip_media_types.
* ast_sip_is_media_type_in tests if one media type is in a list
  of others.

Added static definitions for commonly used media types to
res_pjsip.h.

Changed several modules to use the new functions and static
definitions.

ASTERISK_29813
(not ready to close)

Change-Id: Ief77675235bd3bf00a6b095d4673fd878d0801b9

include/asterisk/res_pjsip.h

@@ -953,6 +953,40 @@ struct ast_sip_endpoint {
 #define AST_SIP_X_AST_TXP "x-ast-txp"
 #define AST_SIP_X_AST_TXP_LEN 9
 
+/*! Common media types used throughout res_pjsip and pjproject */
+extern pjsip_media_type pjsip_media_type_application_json;
+extern pjsip_media_type pjsip_media_type_application_media_control_xml;
+extern pjsip_media_type pjsip_media_type_application_pidf_xml;
+extern pjsip_media_type pjsip_media_type_application_xpidf_xml;
+extern pjsip_media_type pjsip_media_type_application_cpim_xpidf_xml;
+extern pjsip_media_type pjsip_media_type_application_rlmi_xml;
+extern pjsip_media_type pjsip_media_type_application_simple_message_summary;
+extern pjsip_media_type pjsip_media_type_application_sdp;
+extern pjsip_media_type pjsip_media_type_multipart_alternative;
+extern pjsip_media_type pjsip_media_type_multipart_mixed;
+extern pjsip_media_type pjsip_media_type_multipart_related;
+extern pjsip_media_type pjsip_media_type_text_plain;
+
+/*!
+ * \brief Compare pjsip media types
+ *
+ * \param pjsip_media_type a
+ * \param pjsip_media_type b
+ * \retval 1 Media types are equal
+ * \retval 0 Media types are not equal
+ */
+int ast_sip_are_media_types_equal(pjsip_media_type *a, pjsip_media_type *b);
+
+/*!
+ * \brief Check if a media type is in a list of others
+ *
+ * \param a pjsip_media_type to search for
+ * \param ... one or more pointers to pjsip_media_types the last of which must be "SENTINEL"
+ * \retval 1 Media types are equal
+ * \retval 0 Media types are not equal
+ */
+int ast_sip_is_media_type_in(pjsip_media_type *a, ...) attribute_sentinel;
+
 /*!
  * \brief Initialize an auth vector with the configured values.
  *

res/res_pjsip.c

@@ -5292,6 +5292,34 @@ int ast_copy_pj_str2(char **dest, const pj_str_t *src)
 	return res;
 }
 
+int ast_sip_are_media_types_equal(pjsip_media_type *a, pjsip_media_type *b)
+{
+	int rc = 0;
+	if (a != NULL && b != NULL) {
+	    rc = pjsip_media_type_cmp(a, b, 0) ? 0 : 1;
+	}
+	return rc;
+}
+
+int ast_sip_is_media_type_in(pjsip_media_type *a, ...)
+{
+	int rc = 0;
+	pjsip_media_type *b = NULL;
+	va_list ap;
+
+	ast_assert(a != NULL);
+	va_start(ap, a);
+
+	while ((b = va_arg(ap, pjsip_media_type *)) != (pjsip_media_type *)SENTINEL) {
+		if (pjsip_media_type_cmp(a, b, 0) == 0) {
+			rc = 1;
+			break;
+		}
+	}
+	va_end(ap);
+
+	return rc;
+}
 
 int ast_sip_is_content_type(pjsip_media_type *content_type, char *type, char *subtype)
 {
@@ -5844,6 +5872,20 @@ void never_called_res_pjsip(void)
 	pjmedia_strerror(0, NULL, 0);
 }
 
+/* Definitions of media types declared "extern" in res_pjsip.h */
+pjsip_media_type pjsip_media_type_application_json;
+pjsip_media_type pjsip_media_type_application_media_control_xml;
+pjsip_media_type pjsip_media_type_application_pidf_xml;
+pjsip_media_type pjsip_media_type_application_xpidf_xml;
+pjsip_media_type pjsip_media_type_application_cpim_xpidf_xml;
+pjsip_media_type pjsip_media_type_application_rlmi_xml;
+pjsip_media_type pjsip_media_type_application_simple_message_summary;
+pjsip_media_type pjsip_media_type_application_sdp;
+pjsip_media_type pjsip_media_type_multipart_alternative;
+pjsip_media_type pjsip_media_type_multipart_mixed;
+pjsip_media_type pjsip_media_type_multipart_related;
+pjsip_media_type pjsip_media_type_text_plain;
+
 static int load_module(void)
 {
 	struct ast_threadpool_options options;
@@ -5863,6 +5905,21 @@ static int load_module(void)
 		ast_log(LOG_WARNING, "Failed to register pjmedia error codes.  Codes will not be decoded.\n");
 	}
 
+	/* Initialize common media types */
+	pjsip_media_type_init2(&pjsip_media_type_application_json, "application", "json");
+	pjsip_media_type_init2(&pjsip_media_type_application_media_control_xml, "application", "media_control+xml");
+	pjsip_media_type_init2(&pjsip_media_type_application_pidf_xml, "application", "pidf+xml");
+	pjsip_media_type_init2(&pjsip_media_type_application_xpidf_xml, "application", "xpidf+xml");
+	pjsip_media_type_init2(&pjsip_media_type_application_cpim_xpidf_xml, "application", "cpim-xpidf+xml");
+	pjsip_media_type_init2(&pjsip_media_type_application_rlmi_xml, "application", "rlmi+xml");
+	pjsip_media_type_init2(&pjsip_media_type_application_sdp, "application", "sdp");
+	pjsip_media_type_init2(&pjsip_media_type_application_simple_message_summary, "application",	"simple-message-summary");
+	pjsip_media_type_init2(&pjsip_media_type_multipart_alternative, "multipart", "alternative");
+	pjsip_media_type_init2(&pjsip_media_type_multipart_mixed, "multipart", "mixed");
+	pjsip_media_type_init2(&pjsip_media_type_multipart_related, "multipart", "related");
+	pjsip_media_type_init2(&pjsip_media_type_text_plain, "text", "plain");
+
+
 	if (ast_sip_initialize_system()) {
 		ast_log(LOG_ERROR, "Failed to initialize SIP 'system' configuration section. Aborting load\n");
 		goto error;

res/res_pjsip.exports.in

@@ -2,6 +2,7 @@
 	global:
 		LINKER_SYMBOL_PREFIXast_sip_*;
 		LINKER_SYMBOL_PREFIX__ast_sip_*;
+		LINKER_SYMBOL_PREFIXpjsip_media_type_*;
 		LINKER_SYMBOL_PREFIXast_copy_pj_str;
 		LINKER_SYMBOL_PREFIXast_copy_pj_str2;
 		LINKER_SYMBOL_PREFIXast_pjsip_rdata_get_endpoint;

res/res_pjsip_sdp_rtp.c

@@ -2317,9 +2317,8 @@ static int video_info_incoming_request(struct ast_sip_session *session, struct p
 	pjsip_tx_data *tdata;
 
 	if (!session->channel
-		|| !ast_sip_is_content_type(&rdata->msg_info.msg->body->content_type,
-			"application",
-			"media_control+xml")) {
+		|| !ast_sip_are_media_types_equal(&rdata->msg_info.msg->body->content_type,
+			&pjsip_media_type_application_media_control_xml)) {
 		return 0;
 	}
 

res/res_pjsip_session.c

@@ -3893,9 +3893,8 @@ static int check_content_disposition(pjsip_rx_data *rdata)
 	pjsip_ctype_hdr *ctype_hdr = rdata->msg_info.ctype;
 
 	if (body && ctype_hdr &&
-		!pj_stricmp2(&ctype_hdr->media.type, "multipart") &&
-		(!pj_stricmp2(&ctype_hdr->media.subtype, "mixed") ||
-		 !pj_stricmp2(&ctype_hdr->media.subtype, "alternative"))) {
+		ast_sip_is_media_type_in(&ctype_hdr->media, &pjsip_media_type_multipart_mixed,
+			&pjsip_media_type_multipart_alternative, SENTINEL)) {
 		pjsip_multipart_part *part = pjsip_multipart_get_first_part(body);
 		while (part != NULL) {
 			if (check_content_disposition_in_multipart(part)) {
@@ -5488,7 +5487,7 @@ static void session_outgoing_nat_hook(pjsip_tx_data *tdata, struct ast_sip_trans
 
 	/* SDP produced by us directly will never be multipart */
 	if (!transport_state || hook || !tdata->msg->body ||
-		!ast_sip_is_content_type(&tdata->msg->body->content_type, "application", "sdp") ||
+		!ast_sip_are_media_types_equal(&tdata->msg->body->content_type, &pjsip_media_type_application_sdp) ||
 		ast_strlen_zero(transport->external_media_address)) {
 		return;
 	}