sip: added Remote-Party-ID, P-Asserted-Identity, P-Preferred-Identity

Added functions sip_update_default_mclass() and sip_extend_mclass()
for handling the extended parser. Note that Reply-To and Alert-Info are only
available with the extended parser.

darcs-hash:20070919225959-65a35-6727d2eb6dd015e46ba88a556ca32a8e5c8e9369.gz

libsofia-sip-ua/sip/ADD-A-HEADER

-Description of Adding a SIP Header to Sofia SIP
-===============================================
+Adding a SIP Header to Sofia SIP
+================================
 
-by Pekka Pessi (2002-08-16, updated 2006-10-03)
+by Pekka Pessi (2002-08-16, last updated 2007-09-19)
 
-There are three ways to extend the Sofia SIP parser, including a standard
-header in sip_t structure, including a standard header in extra headers or
-putting the extension headers into a separate library.
-
-Probalem with extending #sip_t is that it breaks binary compatibility.
+There are two recommended ways to extend the Sofia SIP parser, including a
+standard header in extra headers or putting the extension headers into a
+separate library.
 
 In the text below, we use "Example" header as our example with following
 ABNF:
@@ -18,30 +16,18 @@ ABNF:
 IF YOUR HEADER IS A STANDARD ONE
 --------------------------------
 
-  * In <sip.h>, add:
+  * In <sofia-sip/sip_extra.h>, add:
 
   - Add typedef to the header structure.
 
-    The typedefs to ordinary headers are in more or less alphabetic
-    order after typedef of sip_unknown_t. You should add a typedef line
-    like this:
+    You should add a typedef line like this:
 
      typedef struct sip_example_s sip_example_t;
 	
     Note that the typedefs are documented together with the
     implementation in the .c file.
 
-  - Add field to the sip_t structure (struct sip_s)
-    - Remember to add a comment containing the header name
-      after field for benefit of the AWK script autmatically generating
-      boilerplate functions and macros:
-      sip_example_t *sip_example; /**< Example */
-    - The AWK script msg_parser.awk automatically creates the default
-      prototypes and tags for the newly created header when the entry in
-      sip_t structure is formatted like to the example above. 
-      It will complain about mismatches between header name and field name.
-
-  * Add the actual header structure:
+ - Add the actual header structure:
 
     The header structure would look like below. The first field MUST be a
     sip_common_t structure, second field MUST be a pointer to next header
@@ -61,6 +47,21 @@ IF YOUR HEADER IS A STANDARD ONE
          unsigned long  ex_value;	    /**< Value of example. */
        };
 
+  * Add entry to sip_extra_headers.txt:
+   - In this case:
+     example @NEW_2_0 /* Example header */
+   - The first is the base C name used for functions and types related to 
+     the type. The AWK script msg_parser.awk automatically creates the
+     default prototypes and tags for the newly created header. It will
+     complain about mismatches between header name and the base name.
+
+   - If the entry is before #### DEFAULT HEADER LIST ENDS HERE #### 
+     the new header is added to the default parser
+   - If after, the new header is added only to the extended parser.
+
+   - The extended parser will be used after call to 
+     sip_update_default_mclass(NULL)
+
   * Write parsing tests for your new headers in torture_sip.c:
 
     Add all relevant parsing/processing cases you can think of
@@ -86,8 +87,10 @@ IF YOUR HEADER IS A STANDARD ONE
   * Run "make check" after you are ready. Really.
 
 
-IF YOUR HEADERS ARE NON-STANDARD
---------------------------------
+IF YOUR HEADERS ARE COMPLETELY NON-STANDARD
+-------------------------------------------
+
+  * Add a separate library package for them
 
     - There is an example package sofia-sip-2543.tar.gz, available from
       sofia-sip.sourceforge.net
@@ -147,6 +150,3 @@ struct sip_example_dummy_structure {
 
 #endif /** !defined(SIP_EXAMPLE_H) */
 --->8---->8---->8---->8---->8---->8---->8---->8---->8---->8---->8---->8---
-
-
-

libsofia-sip-ua/sip/sip.doxyaliases

@@ -69,4 +69,6 @@ ALIASES += \
  "ReplyTo=@ref sip_reply_to \"Reply-To\"" \
  "SuppressBodyIfMatch=@ref sip_suppress_body_if_match \"Suppress-Body-If-Match\"" \
  "SuppressNotifyIfMatch=@ref sip_suppress_notify_if_match \"Suppress-Notify-If-Match\"" \
-  
+ "RemotePartyID=@ref sip_remote_party_id \"Remote-Party-ID\"" \  
+ "PAssertedIdentity=@ref sip_p_asserted_identity \"P-Asserted-Identity\"" \  
+ "PPreferredIdentity=@ref sip_p_preferred_identity \"P-Preferred-Identity\"" \  

libsofia-sip-ua/sip/sip_extra.c

@@ -219,7 +219,9 @@ issize_t sip_error_info_e(char b[], isize_t bsiz, sip_header_t const *h, int f)
  *
  * The parsed Alert-Info header is stored in #sip_alert_info_t structure.
  *
- * @NEW_1_12_7
+ * @NEW_1_12_7. In order to use @b Alert-Info header, 
+ * initialize the SIP parser with, e.g.,
+ * sip_update_default_mclass(sip_extend_mclass(NULL))
  */
 
 /**@ingroup sip_alert_info
@@ -276,6 +278,12 @@ issize_t sip_alert_info_e(char b[], isize_t bsiz, sip_header_t const *h, int f)
  * @endcode
  *
  * The parsed Reply-To header is stored in #sip_reply_to_t structure.
+ *
+ * @sa sip_update_default_mclass()
+ *
+ * @NEW_1_12_7. In order to use @b Reply-To header,
+ * initialize the SIP parser with, e.g.,
+ * sip_update_default_mclass(sip_extend_mclass(NULL)).
  */
 
 /**@ingroup sip_reply_to
@@ -336,11 +344,10 @@ static isize_t sip_reply_to_dup_xtra(sip_header_t const *h, isize_t offset)
 {
   sip_reply_to_t const *rplyto = (sip_reply_to_t const *)h;
 
-  MSG_PARAMS_SIZE(offset, rplyto->rplyto_params);
-  offset += MSG_STRING_SIZE(rplyto->rplyto_display);
-  offset += url_xtra(rplyto->rplyto_url);
-
-  return offset;
+  return sip_name_addr_xtra(rplyto->rplyto_display,
+			    rplyto->rplyto_url,
+			    rplyto->rplyto_params,
+			    offset);
 }
 
 /**@internal Duplicate one sip_reply_to_t object. */
@@ -349,15 +356,11 @@ static char *sip_reply_to_dup_one(sip_header_t *dst, sip_header_t const *src,
 {
   sip_reply_to_t *rplyto = (sip_reply_to_t *)dst;
   sip_reply_to_t const *o = (sip_reply_to_t *)src;
-  char *end = b + xtra;
-
-  b = msg_params_dup(&rplyto->rplyto_params, o->rplyto_params, b, xtra);
-  MSG_STRING_DUP(b, rplyto->rplyto_display, o->rplyto_display);
-  URL_DUP(b, end, rplyto->rplyto_url, o->rplyto_url);
 
-  assert(b <= end);
-
-  return b;
+  return sip_name_addr_dup(&rplyto->rplyto_display, o->rplyto_display,
+			   rplyto->rplyto_url, o->rplyto_url,
+			   &rplyto->rplyto_params, o->rplyto_params,
+			   b, xtra);
 }
 
 /* ====================================================================== */
@@ -889,10 +892,10 @@ isize_t sip_info_dup_xtra(sip_header_t const *h, isize_t offset)
 {
   sip_call_info_t const *ci = h->sh_call_info;
 
-  MSG_PARAMS_SIZE(offset, ci->ci_params);
-  offset += url_xtra(ci->ci_url);
-
-  return offset;
+  return sip_name_addr_xtra(NULL,
+			    ci->ci_url,
+			    ci->ci_params,
+			    offset);
 }
 
 char *sip_info_dup_one(sip_header_t *dst,
@@ -902,14 +905,11 @@ char *sip_info_dup_one(sip_header_t *dst,
 {
   sip_call_info_t *ci = dst->sh_call_info;
   sip_call_info_t const *o = src->sh_call_info;
-  char *end = b + xtra;
-
-  b = msg_params_dup(&ci->ci_params, o->ci_params, b, xtra);
-  URL_DUP(b, end, ci->ci_url, o->ci_url);
-
-  assert(b <= end);
 
-  return b;
+  return sip_name_addr_dup(NULL, NULL,
+			   ci->ci_url, o->ci_url,
+			   &ci->ci_params, o->ci_params,
+			   b, xtra);
 }
 
 /* ====================================================================== */
@@ -1047,3 +1047,319 @@ issize_t sip_suppress_notify_if_match_e(char b[], isize_t bsiz,
 }
 
 #endif
+
+#if SIP_HAVE_REMOTE_PARTY_ID
+
+/**@SIP_HEADER sip_remote_party_id Remote-Party-ID Header
+ *
+ * The syntax of the Remote-Party-ID header is described as follows:
+ * @code
+ *   Remote-Party-ID  = "Remote-Party-ID" HCOLON rpid *(COMMA rpid)
+ *
+ *   rpid             =  [display-name] LAQUOT addr-spec RAQUOT
+ *                                                 *(SEMI rpi-token)
+ *
+ *   rpi-token        = rpi-screen / rpi-pty-type /
+ *                       rpi-id-type / rpi-privacy / other-rpi-token
+ *
+ *   rpi-screen       = "screen" EQUAL ("no" / "yes")
+ *
+ *   rpi-pty-type     = "party" EQUAL ("calling" / "called" / token)
+ *
+ *   rpi-id-type      = "id-type" EQUAL ("subscriber" / "user" /
+ *                                                  "term"  / token)
+ *
+ *   rpi-privacy      = "privacy" EQUAL
+ *                      ( rpi-priv-element
+ *                        / (LDQUOT rpi-priv-element
+ *                          *(COMMA rpi-priv-element) RDQUOT) )
+ *
+ *   rpi-priv-element = ("full" / "name" / "uri" / "off" / token)
+ *                                      ["-" ( "network" / token )]
+ *
+ *   other-rpi-token  = ["-"] token [EQUAL (token / quoted-string)]
+ *
+ * @endcode
+ *
+ * @sa sip_update_default_mclass(), draft-ietf-sip-privacy-04.txt, @RFC3325
+ *
+ * @NEW_1_12_7. In order to use @b Remote-Party-ID header,
+ * initialize the SIP parser with, e.g.,
+ * sip_update_default_mclass(sip_extend_mclass(NULL)).
+ */
+
+/**@ingroup sip_remote_party_id
+ * @typedef typedef struct sip_remote_party_id_s sip_remote_party_id_t;
+ *
+ * The structure #sip_remote_party_id_t contains representation of SIP
+ * @RemotePartyID header.
+ *
+ * The #sip_remote_party_id_t is defined as follows:
+ * @code
+ * typedef struct sip_remote_party_id_s {
+ *   sip_common_t           rpid_common[1]; // Common fragment info
+ *   sip_remote_party_id_t *rpid_next;      // Link to next
+ *   char const        *rpid_display;       // Display name
+ *   url_t              rpid_url[1];        // URL
+ *   sip_param_t const *rpid_params;        // Parameters
+ *   // Shortcuts to screen, party, id-type and privacy parameters
+ *   char const        *rpid_screen, *rpid_party, *rpid_id_type, *rpid_privacy;
+ * } sip_remote_party_id_t;
+ * @endcode
+ */
+
+extern msg_xtra_f sip_remote_party_id_dup_xtra;
+extern msg_dup_f sip_remote_party_id_dup_one;
+
+static msg_update_f sip_remote_party_id_update;
+
+msg_hclass_t sip_remote_party_id_class[] =
+SIP_HEADER_CLASS(remote_party_id, "Remote-Party-ID", "",
+		 rpid_params, append, remote_party_id);
+
+issize_t sip_remote_party_id_d(su_home_t *home, sip_header_t *h,
+			       char *s, isize_t slen)
+{
+  sip_remote_party_id_t *rpid = (sip_remote_party_id_t *)h;
+
+  while (*s == ',')   /* Ignore empty entries (comma-whitespace) */
+    *s = '\0', s += span_lws(s + 1) + 1;
+
+  if (sip_name_addr_d(home, &s,
+		      &rpid->rpid_display,
+		      rpid->rpid_url,
+		      &rpid->rpid_params, NULL) == -1)
+    return -1;
+
+  return msg_parse_next_field(home, h, s, slen);
+}
+
+issize_t sip_remote_party_id_e(char b[], isize_t bsiz,
+			       sip_header_t const *h, int f)
+{
+  sip_remote_party_id_t const *rpid = (sip_remote_party_id_t *)h;
+
+  return sip_name_addr_e(b, bsiz, f,
+			 rpid->rpid_display, 1,
+			 rpid->rpid_url,
+			 rpid->rpid_params,
+			 NULL);
+}
+
+/** Calculate size of extra data required for duplicating one
+ *  sip_remote_party_id_t header. 
+ */
+isize_t sip_remote_party_id_dup_xtra(sip_header_t const *h, isize_t offset)
+{
+  sip_remote_party_id_t const *rpid = (sip_remote_party_id_t *)h;
+  return sip_name_addr_xtra(rpid->rpid_display, 
+			    rpid->rpid_url,
+			    rpid->rpid_params,
+			    offset);
+}
+
+/** Duplicate one sip_remote_party_id_t object */
+char *sip_remote_party_id_dup_one(sip_header_t *dst,
+				  sip_header_t const *src,
+				  char *b, int xtra)
+{
+  sip_remote_party_id_t *rpid = (sip_remote_party_id_t *)dst;
+  sip_remote_party_id_t const *o = (sip_remote_party_id_t const *)src;
+
+  return sip_name_addr_dup(&rpid->rpid_display, o->rpid_display,
+			   rpid->rpid_url, o->rpid_url,
+			   &rpid->rpid_params, o->rpid_params,
+			   b, xtra);
+}
+
+static int sip_remote_party_id_update(msg_common_t *h, 
+				      char const *name, int namelen,
+				      char const *value)
+{
+  sip_remote_party_id_t *rpid = (sip_remote_party_id_t *)h;
+
+  if (name == NULL) {
+    rpid->rpid_screen = NULL;
+    rpid->rpid_party = NULL;
+    rpid->rpid_id_type = NULL;
+    rpid->rpid_privacy = NULL;
+  }
+
+#define MATCH(s) (namelen == strlen(#s) && !strncasecmp(name, #s, strlen(#s)))
+
+  else if (MATCH(screen))
+    rpid->rpid_screen = value;
+  else if (MATCH(party))
+    rpid->rpid_party = value;
+  else if (MATCH(id-type))
+    rpid->rpid_id_type = value;
+  else if (MATCH(privacy))
+    rpid->rpid_privacy = value;
+
+#undef MATCH
+
+  return 0;
+}
+
+#endif
+
+#if SIP_HAVE_P_ASSERTED_IDENTITY
+
+/**@SIP_HEADER sip_p_asserted_identity P-Asserted-Identity Header
+ *
+ * The P-Asserted-Identity header is used used among trusted SIP entities
+ * (typically intermediaries) to carry the identity of the user sending a
+ * SIP message as it was verified by authentication. It is "defined" in
+ * @RFC3325 section 9.1 as follows:
+ *
+ * @code
+ *    PAssertedID = "P-Asserted-Identity" HCOLON PAssertedID-value
+ *                    *(COMMA PAssertedID-value)
+ *    PAssertedID-value = name-addr / addr-spec
+ * @endcode
+ *
+ * @sa @RFC3325, @PPreferredIdentity
+ *
+ * @NEW_1_12_7. In order to use @b P-Asserted-Identity header, 
+ * initialize the SIP parser with, e.g.,
+ * sip_update_default_mclass(sip_extend_mclass(NULL)).
+ */
+
+/**@ingroup sip_p_asserted_identity
+ * @typedef typedef struct sip_p_asserted_identity_s sip_p_asserted_identity_t;
+ *
+ * The structure #sip_p_asserted_identity_t contains representation of SIP
+ * @PAssertedIdentity header.
+ *
+ * The #sip_p_asserted_identity_t is defined as follows:
+ * @code
+ * typedef struct sip_p_asserted_identity_s {
+ *   sip_common_t           paid_common[1];   // Common fragment info
+ *   sip_p_asserted_identity_t *paid_next;    // Link to next
+ *   char const                *paid_display; // Display name
+ *   url_t                      paid_url[1];  // URL
+ * } sip_p_asserted_identity_t;
+ * @endcode
+ */
+
+static msg_xtra_f sip_p_asserted_identity_dup_xtra;
+static msg_dup_f sip_p_asserted_identity_dup_one;
+
+#define sip_p_asserted_identity_update NULL
+
+msg_hclass_t sip_p_asserted_identity_class[] =
+SIP_HEADER_CLASS(p_asserted_identity, "P-Asserted-Identity", "",
+		 paid_common, append, p_asserted_identity);
+
+issize_t sip_p_asserted_identity_d(su_home_t *home, sip_header_t *h,
+				   char *s, isize_t slen)
+{
+  sip_p_asserted_identity_t *paid = (sip_p_asserted_identity_t *)h;
+
+  while (*s == ',')   /* Ignore empty entries (comma-whitespace) */
+    *s = '\0', s += span_lws(s + 1) + 1;
+
+  if (sip_name_addr_d(home, &s,
+		      &paid->paid_display,
+		      paid->paid_url,
+		      NULL, NULL) == -1)
+    return -1;
+
+  return msg_parse_next_field(home, h, s, slen);
+}
+
+issize_t sip_p_asserted_identity_e(char b[], isize_t bsiz,
+				   sip_header_t const *h, int f)
+{
+  sip_p_asserted_identity_t const *paid = (sip_p_asserted_identity_t *)h;
+
+  return sip_name_addr_e(b, bsiz, f,
+			 paid->paid_display, MSG_IS_CANONIC(f),
+			 paid->paid_url,
+			 NULL,
+			 NULL);
+}
+
+isize_t sip_p_asserted_identity_dup_xtra(sip_header_t const *h, isize_t offset)
+{
+  sip_p_asserted_identity_t const *paid = (sip_p_asserted_identity_t *)h;
+
+  return sip_name_addr_xtra(paid->paid_display, 
+			    paid->paid_url,
+			    NULL,
+			    offset);
+}
+
+/** Duplicate one sip_p_asserted_identity_t object */
+char *sip_p_asserted_identity_dup_one(sip_header_t *dst,
+				      sip_header_t const *src,
+				      char *b, isize_t xtra)
+{
+  sip_p_asserted_identity_t *paid = (sip_p_asserted_identity_t *)dst;
+  sip_p_asserted_identity_t const *o = (sip_p_asserted_identity_t *)src;
+
+  return sip_name_addr_dup(&paid->paid_display, o->paid_display,
+			   paid->paid_url, o->paid_url,
+			   NULL, NULL,
+			   b, xtra);
+}
+
+#endif
+
+#if SIP_HAVE_P_PREFERRED_IDENTITY
+
+/**@SIP_HEADER sip_p_preferred_identity P-Preferred-Identity Header
+ *
+ * The P-Preferred-Identity header is used used among trusted SIP entities
+ * (typically intermediaries) to carry the identity of the user sending a
+ * SIP message as it was verified by authentication. It is "defined" in
+ * @RFC3325 section 9.1 as follows:
+ *
+ * @code
+ *    PPreferredID = "P-Preferred-Identity" HCOLON PPreferredID-value
+ *                    *(COMMA PPreferredID-value)
+ *    PPreferredID-value = name-addr / addr-spec
+ * @endcode
+ *
+ * @sa @RFC3325, @PAssertedIdentity
+ *
+ * @NEW_1_12_7. In order to use @b P-Preferred-Identity header,
+ * initialize the SIP parser with, e.g.,
+ * sip_update_default_mclass(sip_extend_mclass(NULL)).
+ */
+
+/**@ingroup sip_p_preferred_identity
+ * @typedef typedef struct sip_p_preferred_identity_s sip_p_preferred_identity_t;
+ *
+ * The structure #sip_p_preferred_identity_t contains representation of SIP
+ * @PPreferredIdentity header.
+ *
+ * The #sip_p_preferred_identity_t is defined as follows:
+ * @code
+ * typedef struct sip_p_preferred_identity_s {
+ *   sip_common_t           ppid_common[1]; // Common fragment info
+ *   sip_p_preferred_identity_t *ppid_next; // Link to next
+ *   char const        *ppid_display;       // Display name
+ *   url_t              ppid_url[1];        // URL
+ * } sip_p_preferred_identity_t;
+ * @endcode
+ */
+
+
+msg_hclass_t sip_p_preferred_identity_class[] =
+SIP_HEADER_CLASS(p_preferred_identity, "P-Preferred-Identity", "",
+		 ppid_common, append, p_asserted_identity);
+
+issize_t sip_p_preferred_identity_d(su_home_t *home, sip_header_t *h,
+				    char *s, isize_t slen)
+{
+  return sip_p_asserted_identity_d(home, h, s, slen);
+}
+
+issize_t sip_p_preferred_identity_e(char b[], isize_t bsiz,
+				    sip_header_t const *h, int f)
+{
+  return sip_p_asserted_identity_e(b, bsiz, h, f);
+}
+
+#endif 

libsofia-sip-ua/sip/sip_extra_headers.txt

 #
 # This file specifies extra SIP headers not included in sip_t structure
 #
+# The parsed headers are accessed with function (or macro) like sip_refer_sub()
+# e.g., sip_refer_sub_t *rsub = sip_refer_sub(sip);
+#
 # The line format is: 
 # C-name @SINCE sip_t-like-comment
 #
@@ -9,8 +12,19 @@
 #### EXTRA HEADER LIST STARTS HERE ####
 
 refer_sub @NEW_1_12_5 /**< Refer-Sub header */
+
+#### DEFAULT HEADER LIST ENDS HERE ####
+
+#
+# These headers are added to the extended parser, installed
+# as default with sip_update_default_mclass(NULL)
+#
+
 alert_info @NEW_1_12_7 /**< Alert-Info header */
 reply_to @NEW_1_12_7 /**< Reply-To header */
+remote_party_id @NEW_1_12_7 /**< Remote-Party-ID header */
+p_asserted_identity @NEW_1_12_7  /**<P-Asserted-Identity*/
+p_preferred_identity @NEW_1_12_7 /**<P-Preferred-Identity*/
 
 #### EXPERIMENTAL HEADER LIST STARTS HERE ####
 

libsofia-sip-ua/sip/sip_parser.c

@@ -60,11 +60,84 @@ char const sip_parser_version[] = VERSION;
 char const sip_version_2_0[] = "SIP/2.0";
 
 /** Default message class */
-extern msg_mclass_t const sip_mclass[];
+extern msg_mclass_t sip_mclass[];
 
+static msg_mclass_t const *_default = sip_mclass;
+
+/** Return a built-in SIP parser object. */
 msg_mclass_t const *sip_default_mclass(void)
 {
-  return sip_mclass;
+  return _default;
+}
+
+/** Update the default SIP parser.
+ *
+ * Use the extended SIP parser as default one.
+ *
+ * If the applications want to use headers added after @VERSION_1_12_5,
+ * they should call this function before doing any other initialization, e.g.,
+ * @code
+ *   su_init();
+ *   if (sip_update_default_mclass(sip_extend_mclass(NULL)) < 0) {
+ *     su_deinit();
+ *     exit(2);
+ *   }
+ * @endcode
+ *
+ * The default parser is not extended because it may break the old
+ * applications looking for extension headers from sip_unknown list.
+ *
+ * @retval 0 when successful
+ * @retval -1 upon an error
+ *
+ * @NEW_1_12_7
+ */
+int sip_update_default_mclass(msg_mclass_t const *mclass)
+{
+  if (mclass == NULL)
+    return -1;
+  _default = mclass;
+  return 0;
+}
+
+/**Extend SIP parser class with extension headers.
+ *
+ * Extend given SIP parser class with extension headers. If the given parser
+ * class is the default one or NULL, make a clone of it before extending it.
+ *
+ * @param input pointer to a SIP message class (may be NULL)
+ *
+ * @return Pointer to extended mclass, or NULL upon an error.
+ *
+ * @NEW_1_12_7
+ */
+msg_mclass_t *sip_extend_mclass(msg_mclass_t *input)
+{
+  msg_mclass_t *mclass;
+
+  if (input == NULL || input == _default)
+    mclass = msg_mclass_clone(_default, 0, 0);
+  else
+    mclass = input;
+
+  if (mclass) {
+    extern msg_hclass_t const * const sip_extensions[];
+    int i;
+
+    for (i = 0; sip_extensions[i]; i++) {
+      msg_hclass_t const *hclass = sip_extensions[i];
+      if (mclass->mc_unknown != msg_find_hclass(mclass, hclass->hc_name, NULL))
+	continue;
+
+      if (msg_mclass_insert_header(mclass, hclass, 0) < 0) {
+	if (input != mclass)
+	  free(mclass);
+	return mclass = NULL;
+      }