stanza: return const char* for non allocated strings

If interface function returns char* the result must be freed with
xmpp_free().

In case of const char* the result must not be changed by user. Also, the
result is valid only during stanza lifetime.

examples/active.c

@@ -24,7 +24,7 @@ int handle_reply(xmpp_conn_t * const conn,
 		 void * const userdata)
 {
     xmpp_stanza_t *query, *item;
-    char *type;
+    const char *type;
 
     type = xmpp_stanza_get_type(stanza);
     if (strcmp(type, "error") == 0)

examples/bot.c

@@ -26,7 +26,7 @@
 int version_handler(xmpp_conn_t * const conn, xmpp_stanza_t * const stanza, void * const userdata)
 {
 	xmpp_stanza_t *reply, *query, *name, *version, *text;
-	char *ns;
+	const char *ns;
 	xmpp_ctx_t *ctx = (xmpp_ctx_t*)userdata;
 	printf("Received version request from %s\n", xmpp_stanza_get_from(stanza));
 	

examples/roster.c

@@ -23,7 +23,7 @@ int handle_reply(xmpp_conn_t * const conn,
 		 void * const userdata)
 {
     xmpp_stanza_t *query, *item;
-    char *type, *name;
+    const char *type, *name;
 
     type = xmpp_stanza_get_type(stanza);
     if (strcmp(type, "error") == 0)

src/auth.c

@@ -111,7 +111,7 @@ static int _handle_error(xmpp_conn_t * const conn,
 			 void * const userdata)
 {
     xmpp_stanza_t *child;
-    char *name;
+    const char *name;
 
     /* free old stream error if it's still there */
     if (conn->stream_error) {
@@ -130,7 +130,7 @@ static int _handle_error(xmpp_conn_t * const conn,
     if (conn->stream_error) {
 	child = xmpp_stanza_get_children(stanza);
 	do {
-	    char *ns = NULL;
+	    const char *ns = NULL;
 
 	    if (child) {
 		ns = xmpp_stanza_get_ns(child);
@@ -279,7 +279,7 @@ static int _handle_proceedtls_default(xmpp_conn_t * const conn,
 			      xmpp_stanza_t * const stanza,
 			      void * const userdata)
 {
-    char *name;
+    const char *name;
 
     name = xmpp_stanza_get_name(stanza);
     xmpp_debug(conn->ctx, "xmpp", "handle proceedtls called for %s", name);
@@ -302,7 +302,7 @@ static int _handle_sasl_result(xmpp_conn_t * const conn,
 			       xmpp_stanza_t * const stanza,
 			       void * const userdata)
 {
-    char *name;
+    const char *name;
 
     name = xmpp_stanza_get_name(stanza);
 
@@ -341,7 +341,7 @@ static int _handle_digestmd5_challenge(xmpp_conn_t * const conn,
     char *text;
     char *response;
     xmpp_stanza_t *auth, *authdata;
-    char *name;
+    const char *name;
 
     name = xmpp_stanza_get_name(stanza);
     xmpp_debug(conn->ctx, "xmpp",\
@@ -396,7 +396,7 @@ static int _handle_digestmd5_rspauth(xmpp_conn_t * const conn,
 			      void * const userdata)
 {
     xmpp_stanza_t *auth;
-    char *name;
+    const char *name;
 
     name = xmpp_stanza_get_name(stanza);
     xmpp_debug(conn->ctx, "xmpp",
@@ -429,7 +429,7 @@ static int _handle_scram_sha1_challenge(xmpp_conn_t * const conn,
     char *text;
     char *response;
     xmpp_stanza_t *auth, *authdata;
-    char *name;
+    const char *name;
     char *challenge;
     char *scram_init = (char *)userdata;
 
@@ -979,7 +979,7 @@ static int _handle_bind(xmpp_conn_t * const conn,
 			xmpp_stanza_t * const stanza,
 			void * const userdata)
 {
-    char *type;
+    const char *type;
     xmpp_stanza_t *iq, *session;
 
     /* delete missing bind handler */
@@ -1062,7 +1062,7 @@ static int _handle_session(xmpp_conn_t * const conn,
 			   xmpp_stanza_t * const stanza,
 			   void * const userdata)
 {
-    char *type;
+    const char *type;
 
     /* delete missing session handler */
     xmpp_timed_handler_delete(conn, _handle_missing_session);
@@ -1099,7 +1099,8 @@ static int _handle_legacy(xmpp_conn_t * const conn,
 			  xmpp_stanza_t * const stanza,
 			  void * const userdata)
 {
-    char *type, *name;
+    const char *type;
+    const char *name;
 
     /* delete missing handler */
     xmpp_timed_handler_delete(conn, _handle_missing_legacy);
@@ -1201,7 +1202,7 @@ int _handle_component_hs_response(xmpp_conn_t * const conn,
             xmpp_stanza_t * const stanza,
             void * const userdata)
 {
-    char *name;
+    const char *name;
 
     xmpp_timed_handler_delete(conn, _handle_missing_handshake);
 

src/handler.c

@@ -35,7 +35,7 @@ void handler_fire_stanza(xmpp_conn_t * const conn,
 			 xmpp_stanza_t * const stanza)
 {
     xmpp_handlist_t *item, *prev;
-    char *id, *ns, *name, *type;
+    const char *id, *ns, *name, *type;
     
     /* call id handlers */
     id = xmpp_stanza_get_id(stanza);

src/stanza.c

@@ -415,9 +415,9 @@ static int _render_stanza_recursive(xmpp_stanza_t *stanza,
  *
  *  @ingroup Stanza
  */
-int  xmpp_stanza_to_text(xmpp_stanza_t *stanza,
+int xmpp_stanza_to_text(xmpp_stanza_t *stanza,
-			 char ** const buf,
+                        char ** const buf,
-			 size_t * const buflen)
+                        size_t * const buflen)
 {
     char *buffer, *tmp;
     size_t length;
@@ -491,7 +491,7 @@ int xmpp_stanza_set_name(xmpp_stanza_t *stanza,
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_name(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_name(xmpp_stanza_t * const stanza)
 {
     if (stanza->type == XMPP_STANZA_TEXT) return NULL;
     return stanza->data;
@@ -710,7 +710,7 @@ int xmpp_stanza_set_text_with_size(xmpp_stanza_t *stanza,
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_id(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_id(xmpp_stanza_t * const stanza)
 {
     return xmpp_stanza_get_attribute(stanza, "id");
 }
@@ -725,7 +725,7 @@ char *xmpp_stanza_get_id(xmpp_stanza_t * const stanza)
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_ns(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_ns(xmpp_stanza_t * const stanza)
 {
     return xmpp_stanza_get_attribute(stanza, "xmlns");
 }
@@ -740,7 +740,7 @@ char *xmpp_stanza_get_ns(xmpp_stanza_t * const stanza)
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_type(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_type(xmpp_stanza_t * const stanza)
 {
     return xmpp_stanza_get_attribute(stanza, "type");
 }
@@ -755,7 +755,7 @@ char *xmpp_stanza_get_type(xmpp_stanza_t * const stanza)
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_to(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_to(xmpp_stanza_t * const stanza)
 {
     return xmpp_stanza_get_attribute(stanza, "to");
 }
@@ -770,7 +770,7 @@ char *xmpp_stanza_get_to(xmpp_stanza_t * const stanza)
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_from(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_from(xmpp_stanza_t * const stanza)
 {
     return xmpp_stanza_get_attribute(stanza, "from");
 }
@@ -915,7 +915,7 @@ char *xmpp_stanza_get_text(xmpp_stanza_t * const stanza)
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_text_ptr(xmpp_stanza_t * const stanza)
+const char *xmpp_stanza_get_text_ptr(xmpp_stanza_t * const stanza)
 {
     if (stanza->type == XMPP_STANZA_TEXT)
 	return stanza->data;
@@ -1004,8 +1004,8 @@ int xmpp_stanza_set_from(xmpp_stanza_t * const stanza,
  *
  *  @ingroup Stanza
  */
-char *xmpp_stanza_get_attribute(xmpp_stanza_t * const stanza,
+const char *xmpp_stanza_get_attribute(xmpp_stanza_t * const stanza,
-				const char * const name)
+                                      const char * const name)
 {
     if (stanza->type != XMPP_STANZA_TAG)
 	return NULL;

strophe.h

@@ -295,7 +295,7 @@ xmpp_stanza_t *xmpp_stanza_new(xmpp_ctx_t *ctx);
 xmpp_stanza_t *xmpp_stanza_clone(xmpp_stanza_t * const stanza);
 
 /** copies a stanza and all children */
-xmpp_stanza_t * xmpp_stanza_copy(const xmpp_stanza_t * const stanza);
+xmpp_stanza_t *xmpp_stanza_copy(const xmpp_stanza_t * const stanza);
 
 /** free a stanza object and it's contents */
 int xmpp_stanza_release(xmpp_stanza_t * const stanza);
@@ -317,21 +317,18 @@ xmpp_stanza_t *xmpp_stanza_get_child_by_name(xmpp_stanza_t * const stanza,
 xmpp_stanza_t *xmpp_stanza_get_child_by_ns(xmpp_stanza_t * const stanza,
 					   const char * const ns);
 xmpp_stanza_t *xmpp_stanza_get_next(xmpp_stanza_t * const stanza);
-char *xmpp_stanza_get_attribute(xmpp_stanza_t * const stanza,
+int xmpp_stanza_add_child(xmpp_stanza_t *stanza, xmpp_stanza_t *child);
-				const char * const name);
+
+const char *xmpp_stanza_get_attribute(xmpp_stanza_t * const stanza,
+				      const char * const name);
 int xmpp_stanza_get_attribute_count(xmpp_stanza_t * const stanza);
 int xmpp_stanza_get_attributes(xmpp_stanza_t * const stanza,
 			       const char **attr, int attrlen);
-char *xmpp_stanza_get_ns(xmpp_stanza_t * const stanza);
 /* concatenate all child text nodes.  this function
  * returns a string that must be freed by the caller */
-
 char *xmpp_stanza_get_text(xmpp_stanza_t * const stanza);
-char *xmpp_stanza_get_text_ptr(xmpp_stanza_t * const stanza);
+const char *xmpp_stanza_get_text_ptr(xmpp_stanza_t * const stanza);
-char *xmpp_stanza_get_name(xmpp_stanza_t * const stanza);
+const char *xmpp_stanza_get_name(xmpp_stanza_t * const stanza);
-
-int xmpp_stanza_add_child(xmpp_stanza_t *stanza, xmpp_stanza_t *child);
-int xmpp_stanza_set_ns(xmpp_stanza_t * const stanza, const char * const ns);
 /* set_attribute adds/replaces attributes */
 int xmpp_stanza_set_attribute(xmpp_stanza_t * const stanza, 
 			      const char * const key,
@@ -343,23 +340,20 @@ int xmpp_stanza_set_text(xmpp_stanza_t *stanza,
 int xmpp_stanza_set_text_with_size(xmpp_stanza_t *stanza,
 				   const char * const text, 
 				   const size_t size);
-
 int xmpp_stanza_del_attribute(xmpp_stanza_t * const stanza,
                               const char * const name);
 
 /* common stanza helpers */
-char *xmpp_stanza_get_type(xmpp_stanza_t * const stanza);
+const char *xmpp_stanza_get_ns(xmpp_stanza_t * const stanza);
-char *xmpp_stanza_get_id(xmpp_stanza_t * const stanza);
+const char *xmpp_stanza_get_type(xmpp_stanza_t * const stanza);
-char *xmpp_stanza_get_to(xmpp_stanza_t * const stanza);
+const char *xmpp_stanza_get_id(xmpp_stanza_t * const stanza);
-char *xmpp_stanza_get_from(xmpp_stanza_t * const stanza);
+const char *xmpp_stanza_get_to(xmpp_stanza_t * const stanza);
-int xmpp_stanza_set_id(xmpp_stanza_t * const stanza, 
+const char *xmpp_stanza_get_from(xmpp_stanza_t * const stanza);
-		       const char * const id);
+int xmpp_stanza_set_ns(xmpp_stanza_t * const stanza, const char * const ns);
-int xmpp_stanza_set_type(xmpp_stanza_t * const stanza, 
+int xmpp_stanza_set_id(xmpp_stanza_t * const stanza, const char * const id);
-			 const char * const type);
+int xmpp_stanza_set_type(xmpp_stanza_t * const stanza, const char * const type);
-int xmpp_stanza_set_to(xmpp_stanza_t * const stanza,
+int xmpp_stanza_set_to(xmpp_stanza_t * const stanza, const char * const to);
-                       const char * const to);
+int xmpp_stanza_set_from(xmpp_stanza_t * const stanza, const char * const from);
-int xmpp_stanza_set_from(xmpp_stanza_t * const stanza,
-                         const char * const from);
 
 /* allocate and initialize a stanza in reply to another */
 xmpp_stanza_t *xmpp_stanza_reply(xmpp_stanza_t * const stanza);