Fix udp:setpeername("*")

There seems to be a curious difference between MacOS and
Linux and I am not sure if this is documented. When you
break a "connection" on Mac OS, you only eliminate the peer
association, but the local address remains bound. On Linux,
breaking a "connection" eliminates the binding to the local
address. Have you guys ever come accross this?

Another irritating difference is that connect() returns the
error EAFNOSUPPORT on Mac OS. I am going to ignore all
errors when the reason for calling connect() is simply to
break the "connection".

.gitignore

@@ -1,3 +1,4 @@
 *.o
 *.so
 *.so.*
+mac

TODO

@@ -1,3 +1,5 @@
+- bizarre default values for getnameinfo should throw error instead!
+
 - document the new bind and connect behavior.
 - shouldn't we instead make the code compatible to Lua 5.2
   without any compat stuff, and use a compatibility layer to

doc/tcp.html

@@ -125,7 +125,9 @@ local host.
 <tt>Port</tt> must be an integer number in the range [0..64K). 
 If <tt>address</tt>
 is '<tt>*</tt>', the system binds to all local interfaces
-using the <tt>INADDR_ANY</tt> constant. If <tt>port</tt> is 0, the system automatically
+using the <tt>INADDR_ANY</tt> constant or
+<tt>IN6ADDR_ANY_INIT</tt>, according to the family. 
+If <tt>port</tt> is 0, the system automatically
 chooses an ephemeral port.  
 </p>
 

src/inet.c

@@ -177,8 +177,8 @@ static int inet_global_getaddrinfo(lua_State *L)
     lua_newtable(L);
     for (iterator = resolved; iterator; iterator = iterator->ai_next) {
         char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
-        getnameinfo(iterator->ai_addr, iterator->ai_addrlen, hbuf, sizeof(hbuf),
-                sbuf, 0, NI_NUMERICHOST);
+        getnameinfo(iterator->ai_addr, iterator->ai_addrlen, hbuf, 
+            sizeof(hbuf), sbuf, 0, NI_NUMERICHOST);
         lua_pushnumber(L, i);
         lua_newtable(L);
         switch (iterator->ai_family) {
@@ -367,6 +367,34 @@ const char *inet_trycreate(p_socket ps, int family, int type) {
     return socket_strerror(socket_create(ps, family, type, 0));
 }
 
+/*-------------------------------------------------------------------------*\
+* "Disconnects" a DGRAM socket
+\*-------------------------------------------------------------------------*/
+const char *inet_trydisconnect(p_socket ps, int family, p_timeout tm)
+{
+    switch (family) {
+        case PF_INET: {
+            struct sockaddr_in sin;
+            memset((char *) &sin, 0, sizeof(sin));
+            sin.sin_family = AF_UNSPEC;
+            sin.sin_addr.s_addr = INADDR_ANY;
+            return socket_strerror(socket_connect(ps, (SA *) &sin, 
+                sizeof(sin), tm));
+        }
+        case PF_INET6: {
+            struct sockaddr_in6 sin6;
+            struct in6_addr addrany = IN6ADDR_ANY_INIT; 
+            memset((char *) &sin6, 0, sizeof(sin6));
+            sin6.sin6_family = AF_UNSPEC;
+fprintf(stderr, "disconnecting\n");
+            sin6.sin6_addr = addrany;
+            return socket_strerror(socket_connect(ps, (SA *) &sin6, 
+                sizeof(sin6), tm));
+        }
+    }
+    return NULL;
+}
+
 /*-------------------------------------------------------------------------*\
 * Tries to connect to remote address (address, port)
 \*-------------------------------------------------------------------------*/
@@ -382,17 +410,14 @@ const char *inet_tryconnect(p_socket ps, const char *address,
         if (resolved) freeaddrinfo(resolved);
         return err;
     }
-    /* iterate over all returned addresses trying to connect */
     for (iterator = resolved; iterator; iterator = iterator->ai_next) {
         timeout_markstart(tm);
         /* try connecting to remote address */
-        err = socket_strerror(socket_connect(ps,
-            (SA *) iterator->ai_addr,
+        err = socket_strerror(socket_connect(ps, (SA *) iterator->ai_addr, 
             iterator->ai_addrlen, tm));
         /* if success, break out of loop */
         if (err == NULL) break;
     }
-
     freeaddrinfo(resolved);
     /* here, if err is set, we failed */
     return err;
@@ -407,12 +432,8 @@ const char *inet_trybind(p_socket ps, const char *address, const char *serv,
     struct addrinfo *iterator = NULL, *resolved = NULL;
     const char *err = NULL;
     t_socket sock = *ps;
-    /* translate luasocket special values to C */
-    if (strcmp(address, "*") == 0) address = NULL;
-    if  (!serv) serv = "0";
     /* try resolving */
-    err = socket_gaistrerror(getaddrinfo(address, serv,
-            bindhints, &resolved));
+    err = socket_gaistrerror(getaddrinfo(address, serv, bindhints, &resolved));
     if (err) {
         if (resolved) freeaddrinfo(resolved);
         return err;
@@ -420,7 +441,7 @@ const char *inet_trybind(p_socket ps, const char *address, const char *serv,
     /* iterate over resolved addresses until one is good */
     for (iterator = resolved; iterator; iterator = iterator->ai_next) {
         if(sock == SOCKET_INVALID) {
-            err = socket_strerror( socket_create(&sock, iterator->ai_family,
+            err = socket_strerror(socket_create(&sock, iterator->ai_family,
                         iterator->ai_socktype, iterator->ai_protocol));
             if(err)
                 continue;

src/inet.h

@@ -29,6 +29,7 @@ const char *inet_tryconnect(p_socket ps, const char *address,
         const char *serv, p_timeout tm, struct addrinfo *connecthints);
 const char *inet_trybind(p_socket ps, const char *address, const char *serv,
         struct addrinfo *bindhints);
+const char *inet_trydisconnect(p_socket ps, int family, p_timeout tm);
 
 int inet_meth_getpeername(lua_State *L, p_socket ps, int family);
 int inet_meth_getsockname(lua_State *L, p_socket ps, int family);

src/tcp.c

@@ -222,6 +222,7 @@ static int meth_bind(lua_State *L)
     bindhints.ai_socktype = SOCK_STREAM;
     bindhints.ai_family = tcp->family;
     bindhints.ai_flags = AI_PASSIVE;
+    address = strcmp(address, "*")? address: NULL;
     err = inet_trybind(&tcp->sock, address, port, &bindhints);
     if (err) {
         lua_pushnil(L);
@@ -247,8 +248,7 @@ static int meth_connect(lua_State *L)
     /* make sure we try to connect only to the same family */
     connecthints.ai_family = tcp->family;
     timeout_markstart(&tcp->tm);
-    err = inet_tryconnect(&tcp->sock, address, port,
-		    &tcp->tm, &connecthints);
+    err = inet_tryconnect(&tcp->sock, address, port, &tcp->tm, &connecthints);
     /* have to set the class even if it failed due to non-blocking connects */
     auxiliar_setclass(L, "tcp{client}", 1);
     if (err) {

src/udp.c

@@ -275,10 +275,10 @@ static int meth_receivefrom(lua_State *L) {
 	    }
 	    break;
 	}
-        default:
-            lua_pushnil(L);
-            lua_pushfstring(L, "unknown family %d", udp->family);
-            return 2;
+    default:
+        lua_pushnil(L);
+        lua_pushfstring(L, "unknown family %d", udp->family);
+        return 2;
     }
     lua_pushnil(L);
     lua_pushstring(L, udp_strerror(err));
@@ -366,27 +366,30 @@ static int meth_settimeout(lua_State *L) {
 static int meth_setpeername(lua_State *L) {
     p_udp udp = (p_udp) auxiliar_checkgroup(L, "udp{any}", 1);
     p_timeout tm = &udp->tm;
-    const char *address =  luaL_checkstring(L, 2);
+    const char *address = luaL_checkstring(L, 2);
     int connecting = strcmp(address, "*");
-    const char *port = connecting ?
-        luaL_checkstring(L, 3) :
-        luaL_optstring(L, 3, "0");
+    const char *port = connecting? luaL_checkstring(L, 3): "0";
     struct addrinfo connecthints;
     const char *err;
     memset(&connecthints, 0, sizeof(connecthints));
     connecthints.ai_socktype = SOCK_DGRAM;
     /* make sure we try to connect only to the same family */
     connecthints.ai_family = udp->family;
-    err = inet_tryconnect(&udp->sock, address, port,
-		    tm, &connecthints);
-    if (err) {
-        lua_pushnil(L);
-        lua_pushstring(L, err);
-        return 2;
+    if (connecting) {
+        err = inet_tryconnect(&udp->sock, address, port, tm, &connecthints);
+        if (err) {
+            lua_pushnil(L);
+            lua_pushstring(L, err);
+            return 2;
+        }
+        auxiliar_setclass(L, "udp{connected}", 1);
+    } else {
+        /* we ignore possible errors because Mac OS X always
+         * returns EAFNOSUPPORT */
+        inet_trydisconnect(&udp->sock, udp->family, tm);
+        auxiliar_setclass(L, "udp{unconnected}", 1);
     }
     /* change class to connected or unconnected depending on address */
-    if (connecting) auxiliar_setclass(L, "udp{connected}", 1);
-    else auxiliar_setclass(L, "udp{unconnected}", 1);
     lua_pushnumber(L, 1);
     return 1;
 }

test/udpconnectclnt.lua

@@ -0,0 +1,19 @@
+local socket = require"socket"
+local udp = socket.udp
+local localhost = "127.0.0.1"
+local port = arg[1]
+
+se = udp(); se:setoption("reuseaddr", true)
+se:setsockname(localhost, 5062)
+print("se", se:getsockname())
+sc = udp(); sc:setoption("reuseaddr", true)
+sc:setsockname(localhost, 5061)
+print("sc", sc:getsockname())
+
+se:sendto("this is a test from se", localhost, port)
+socket.sleep(1)
+sc:sendto("this is a test from sc", localhost, port)
+socket.sleep(1)
+se:sendto("this is a test from se", localhost, port)
+socket.sleep(1)
+sc:sendto("this is a test from sc", localhost, port)

test/udpconnectsrvr.lua

@@ -0,0 +1,16 @@
+local socket = require"socket"
+local udp = socket.udp
+local localhost = "127.0.0.1"
+local s = assert(udp())
+assert(tostring(s):find("udp{unconnected}"))
+print("setpeername", s:setpeername(localhost, 5061))
+print("getsockname", s:getsockname())
+assert(tostring(s):find("udp{connected}"))
+print(s:receive())
+print("setpeername", s:setpeername("*"))
+print("getsockname", s:getsockname())
+s:sendto("a", localhost, 12345)
+print("getsockname", s:getsockname())
+assert(tostring(s):find("udp{unconnected}"))
+print(s:receivefrom())
+s:close()