added 'star' as special word for the contact option -C

git-svn-id: http://svn.berlios.de/svnroot/repos/sipsak/trunk@426 75b5f7c7-cfd4-0310-b54c-e118b2c5249a
(cherry picked from commit 3860d1a03ef2d9840487969994fa3a68ff4d9d85)

sipsak.1

@@ -175,6 +175,12 @@ or
 .B none
 will result in no contact header in the REGISTER request and thus the server
 should answer with the current bindings for the account at the registrar.
+The special words 
+.B *
+or
+.B star
+will result in Contact header containing just a star, e.g. to remove all
+bindings by using expires value 0 together with this Contact.
 
 .IP "-d, --ignore-redirects"
 If this option is set all redirects will be ignored. By default without this 

sipsak.c

@@ -393,7 +393,8 @@ int main(int argc, char *argv[])
 					(strlen(optarg) == 4 && STRNCASECMP(optarg, "none", 4) == 0)) {
 					empty_contact = 1;
 				}
-				else if (strlen(optarg) == 1 && STRNCASECMP(optarg, "*", 1) == 0) {
+				else if ((strlen(optarg) == 1 && STRNCASECMP(optarg, "*", 1) == 0) ||
+						(strlen(optarg) == 4 && STRNCASECMP(optarg, "star", 4) == 0)) {
 					contact_uri=str_alloc(strlen(optarg)+1);
 					strncpy(contact_uri, optarg, strlen(optarg));
 				}