Fix crash while receiving some kind of invalid from header.

README.md

@@ -61,7 +61,8 @@ Generating the grammar sources
 
 If you edit the `.g` files in the grammars directory you'll need to regenerate the sources.
 
-    ./src/antlr3c/generate_grammar_sources.py
+    cd src/antlr3c
+    ./generate_grammar_sources.py
 
 Build options
 -------------

src/grammars/belle_sdpLexer.c

@@ -2,7 +2,7 @@
  *  This C source file was generated by $ANTLR version 3.4
  *
  *     -  From the grammar source file : ../grammars/belle_sdp.g
- *     -                            On : 2021-05-03 11:52:42
+ *     -                            On : 2021-05-13 15:53:02
  *     -                 for the lexer : belle_sdpLexerLexer
  *
  * Editing it, at least manually, is not wise.

src/grammars/belle_sdpLexer.h

@@ -2,7 +2,7 @@
  *  This C header file was generated by $ANTLR version 3.4
  *
  *     -  From the grammar source file : ../grammars/belle_sdp.g
- *     -                            On : 2021-05-03 11:52:42
+ *     -                            On : 2021-05-13 15:53:02
  *     -                 for the lexer : belle_sdpLexerLexer
  *
  * Editing it, at least manually, is not wise.

src/grammars/belle_sdpParser.c

@@ -2,7 +2,7 @@
  *  This C source file was generated by $ANTLR version 3.4
  *
  *     -  From the grammar source file : ../grammars/belle_sdp.g
- *     -                            On : 2021-05-03 11:52:42
+ *     -                            On : 2021-05-13 15:53:02
  *     -                for the parser : belle_sdpParserParser
  *
  * Editing it, at least manually, is not wise.

src/grammars/belle_sdpParser.h

@@ -2,7 +2,7 @@
  *  This C header file was generated by $ANTLR version 3.4
  *
  *     -  From the grammar source file : ../grammars/belle_sdp.g
- *     -                            On : 2021-05-03 11:52:42
+ *     -                            On : 2021-05-13 15:53:02
  *     -                for the parser : belle_sdpParserParser
  *
  * Editing it, at least manually, is not wise.

src/grammars/belle_sip_message.g

@@ -764,8 +764,10 @@ addr_spec[belle_sip_header_address_t* object]
 addr_spec_with_generic_uri[belle_sip_header_address_t* object]
   :  lws? (	uri {belle_sip_header_address_set_uri(object,$uri.ret);}
   	|
-  	generic_uri { if (   strcasecmp(belle_generic_uri_get_scheme($generic_uri.ret),"sip") != 0
-					 &&  strcasecmp(belle_generic_uri_get_scheme($generic_uri.ret),"sips") != 0 ) {
+  	generic_uri {
+		const char *scheme = belle_generic_uri_get_scheme($generic_uri.ret);
+		if ( scheme && strcasecmp(scheme,"sip") != 0
+					 &&  strcasecmp(scheme, "sips") != 0 ) {
 						 belle_sip_header_address_set_absolute_uri(object,$generic_uri.ret);
 					 } else {
 						 belle_sip_message("Cannot parse a sip/sips uri as a generic uri");
@@ -776,9 +778,11 @@ addr_spec_with_generic_uri[belle_sip_header_address_t* object]
   fast_addr_spec_with_generic_uri[belle_sip_header_address_t* object]
   :  lws? (	fast_uri {belle_sip_header_address_set_uri(object,$fast_uri.ret);}
   	|
-  	generic_uri { if (   strcasecmp(belle_generic_uri_get_scheme($generic_uri.ret),"sip") != 0
-					 &&  strcasecmp(belle_generic_uri_get_scheme($generic_uri.ret),"sips") != 0 ) {
-						 belle_sip_header_address_set_absolute_uri(object,$generic_uri.ret);
+  	generic_uri {
+		const char *scheme = belle_generic_uri_get_scheme($generic_uri.ret);
+		if ( scheme && strcasecmp(scheme, "sip") != 0
+					 &&  strcasecmp(scheme, "sips") != 0 ) {
+						 belle_sip_header_address_set_absolute_uri(object, $generic_uri.ret);
 					 } else {
 						 belle_sip_message("Cannot parse a sip/sips uri as a generic uri");
 						 belle_sip_object_unref($generic_uri.ret);