socket.connect now implemented in the C core

This avoid socket.lua duplicating the iteration over the results
of getaddrinfo(). Some problems with the C implementation not
initializing sockets or the luasocket family have also been fixed,
and error reporting made more robust.

doc/reference.html

@@ -145,6 +145,8 @@ Support, Manual">
 <blockquote>
 <a href="socket.html#bind">bind</a>,
 <a href="socket.html#connect">connect</a>,
+<a href="socket.html#connect">connect4</a>,
+<a href="socket.html#connect">connect6</a>,
 <a href="socket.html#debug">_DEBUG</a>,
 <a href="dns.html#dns">dns</a>,
 <a href="socket.html#gettime">gettime</a>,

doc/socket.html

@@ -73,14 +73,19 @@ set to <tt><b>true</b></tt>.
 <!-- connect ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
 
 <p class=name id=connect> 
-socket.<b>connect(</b>address, port [, locaddr, locport]<b>)</b>
+socket.<b>connect[46](</b>address, port [, locaddr] [, locport] [, family]<b>)</b>
 </p>
 
 <p class=description>
 This function is a shortcut that creates and returns a TCP client object
-connected to a remote <tt>host</tt> at a given <tt>port</tt>. Optionally,
+connected to a remote <tt>address</tt> at a given <tt>port</tt>. Optionally,
 the user can also specify the local address and port to bind
-(<tt>locaddr</tt> and <tt>locport</tt>).
+(<tt>locaddr</tt> and <tt>locport</tt>), or restrict the socket family
+to "<tt>inet</tt>" or "<tt>inet6</tt>".
+Without specifying <tt>family</tt> to <tt>connect</tt>, whether a tcp or tcp6
+connection is created depends on your system configuration. Two variations
+of connect are defined as simple helper functions that restrict the
+<tt>family</tt>, <tt>socket.connect4</tt> and <tt>socket.connect6</tt>.
 </p>
 
 <!-- debug ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

src/inet.c

@@ -143,6 +143,22 @@ static int inet_global_toip(lua_State *L)
     return 2;
 }
 
+int inet_optfamily(lua_State* L, int narg, const char* def)
+{
+    static const char* optname[] = { "unspec", "inet", "inet6", NULL };
+    static int optvalue[] = { PF_UNSPEC, PF_INET, PF_INET6, 0 };
+
+    return optvalue[luaL_checkoption(L, narg, def, optname)];
+}
+
+int inet_optsocktype(lua_State* L, int narg, const char* def)
+{
+    static const char* optname[] = { "stream", "dgram", NULL };
+    static int optvalue[] = { SOCK_STREAM, SOCK_DGRAM, 0 };
+
+    return optvalue[luaL_checkoption(L, narg, def, optname)];
+}
+
 static int inet_global_getaddrinfo(lua_State *L)
 {
     const char *hostname = luaL_checkstring(L, 1);
@@ -197,7 +213,7 @@ static int inet_global_gethostname(lua_State *L)
     name[256] = '\0';
     if (gethostname(name, 256) < 0) {
         lua_pushnil(L);
-        lua_pushstring(L, "gethostname failed");
+        lua_pushstring(L, socket_strerror(errno));
         return 2;
     } else {
         lua_pushstring(L, name);
@@ -222,7 +238,7 @@ int inet_meth_getpeername(lua_State *L, p_socket ps, int family)
             char name[INET_ADDRSTRLEN];
             if (getpeername(*ps, (SA *) &peer, &peer_len) < 0) {
                 lua_pushnil(L);
-                lua_pushstring(L, "getpeername failed");
+                lua_pushstring(L, socket_strerror(errno));
                 return 2;
             } else {
                 inet_ntop(family, &peer.sin_addr, name, sizeof(name));
@@ -238,7 +254,7 @@ int inet_meth_getpeername(lua_State *L, p_socket ps, int family)
             char name[INET6_ADDRSTRLEN];
             if (getpeername(*ps, (SA *) &peer, &peer_len) < 0) {
                 lua_pushnil(L);
-                lua_pushstring(L, "getpeername failed");
+                lua_pushstring(L, socket_strerror(errno));
                 return 2;
             } else {
                 inet_ntop(family, &peer.sin6_addr, name, sizeof(name));
@@ -251,7 +267,7 @@ int inet_meth_getpeername(lua_State *L, p_socket ps, int family)
         }
         default:
             lua_pushnil(L);
-            lua_pushstring(L, "unknown family");
+            lua_pushfstring(L, "unknown family %d", family);
             return 2;
     }
 }
@@ -268,7 +284,7 @@ int inet_meth_getsockname(lua_State *L, p_socket ps, int family)
             char name[INET_ADDRSTRLEN];
             if (getsockname(*ps, (SA *) &local, &local_len) < 0) {
                 lua_pushnil(L);
-                lua_pushstring(L, "getsockname failed");
+                lua_pushstring(L, socket_strerror(errno));
                 return 2;
             } else {
                 inet_ntop(family, &local.sin_addr, name, sizeof(name));
@@ -284,7 +300,7 @@ int inet_meth_getsockname(lua_State *L, p_socket ps, int family)
             char name[INET6_ADDRSTRLEN];
             if (getsockname(*ps, (SA *) &local, &local_len) < 0) {
                 lua_pushnil(L);
-                lua_pushstring(L, "getsockname failed");
+                lua_pushstring(L, socket_strerror(errno));
                 return 2;
             } else {
                 inet_ntop(family, &local.sin6_addr, name, sizeof(name));
@@ -296,7 +312,7 @@ int inet_meth_getsockname(lua_State *L, p_socket ps, int family)
         }
         default:
             lua_pushnil(L);
-            lua_pushstring(L, "unknown family");
+            lua_pushfstring(L, "unknown family %d", family);
             return 2;
     }
 }
@@ -390,6 +406,7 @@ 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";
@@ -402,17 +419,30 @@ 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,
+                        iterator->ai_socktype, iterator->ai_protocol));
+            if(err)
+                continue;
+        }
         /* try binding to local address */
-        err = socket_strerror(socket_bind(ps,
+        err = socket_strerror(socket_bind(&sock,
             (SA *) iterator->ai_addr,
             iterator->ai_addrlen));
-        /* if faiiled, we try the next one */
-        if (err != NULL) socket_destroy(ps);
-        /* if success, we abort loop */
-        else break;
+
+        /* keep trying unless bind succeeded */
+        if (err) {
+            if(sock != *ps)
+                socket_destroy(&sock);
+        } else {
+            /* remember what we connected to, particularly the family */
+            *bindhints = *iterator;
+            break;
+        }
     }
     /* cleanup and return error */
     freeaddrinfo(resolved);
+    *ps = sock;
     return err;
 }
 

src/inet.h

@@ -33,6 +33,9 @@ const char *inet_trybind(p_socket ps, const char *address, const char *serv,
 int inet_meth_getpeername(lua_State *L, p_socket ps, int family);
 int inet_meth_getsockname(lua_State *L, p_socket ps, int family);
 
+int inet_optfamily(lua_State* L, int narg, const char* def);
+int inet_optsocktype(lua_State* L, int narg, const char* def);
+
 #ifdef INET_ATON
 int inet_aton(const char *cp, struct in_addr *inp);
 #endif

src/socket.lua

@@ -15,34 +15,12 @@ module("socket")
 -----------------------------------------------------------------------------
 -- Exported auxiliar functions
 -----------------------------------------------------------------------------
-function connect(address, port, laddress, lport)
-    if address == "*" then address = "0.0.0.0" end
-    local addrinfo, err = socket.dns.getaddrinfo(address);
-    if not addrinfo then return nil, err end
-    local sock, res
-    err = "no info on address"
-    for i, alt in base.ipairs(addrinfo) do 
-        if alt.family == "inet" then
-            sock, err = socket.tcp()
-        else
-            sock, err = socket.tcp6()
-        end
-        if not sock then return nil, err end
-        if laddress then
-            res, err = sock:bind(laddress, lport)
-            if not res then 
-                sock:close()
-                return nil, err 
-            end
-        end
-        res, err = sock:connect(alt.addr, port)
-        if not res then 
-            sock:close()
-        else
-            return sock 
-        end
-    end
-    return nil, err
+function connect4(address, port, laddress, lport)
+    return socket.connect(address, port, laddress, lport, "inet")
+end
+
+function connect6(address, port, laddress, lport)
+    return socket.connect(address, port, laddress, lport, "inet6")
 end
 
 function bind(host, port, backlog)

src/tcp.c

@@ -18,7 +18,7 @@
 \*=========================================================================*/
 static int global_create(lua_State *L);
 static int global_create6(lua_State *L);
-static int global_connect6(lua_State *L);
+static int global_connect(lua_State *L);
 static int meth_connect(lua_State *L);
 static int meth_listen(lua_State *L);
 static int meth_getfamily(lua_State *L);
@@ -89,7 +89,7 @@ static t_opt optset[] = {
 static luaL_Reg func[] = {
     {"tcp", global_create},
     {"tcp6", global_create6},
-    {"connect6", global_connect6},
+    {"connect", global_connect},
     {NULL, NULL}
 };
 
@@ -408,6 +408,7 @@ static const char *tryconnect6(const char *remoteaddr, const char *remoteserv,
                 freeaddrinfo(resolved);
                 return err;
             }
+            tcp->family = iterator->ai_family;
             /* all sockets initially non-blocking */
             socket_setnonblocking(&tcp->sock);
         }
@@ -424,11 +425,12 @@ static const char *tryconnect6(const char *remoteaddr, const char *remoteserv,
     return err;
 }
 
-static int global_connect6(lua_State *L) {
+static int global_connect(lua_State *L) {
     const char *remoteaddr = luaL_checkstring(L, 1);
     const char *remoteserv = luaL_checkstring(L, 2);
     const char *localaddr  = luaL_optstring(L, 3, NULL);
     const char *localserv  = luaL_optstring(L, 4, "0");
+    int family = inet_optfamily(L, 5, "unspec");
     p_tcp tcp = (p_tcp) lua_newuserdata(L, sizeof(t_tcp));
     struct addrinfo bindhints, connecthints;
     const char *err = NULL;
@@ -441,7 +443,7 @@ static int global_connect6(lua_State *L) {
     /* allow user to pick local address and port */
     memset(&bindhints, 0, sizeof(bindhints));
     bindhints.ai_socktype = SOCK_STREAM;
-    bindhints.ai_family = PF_UNSPEC;
+    bindhints.ai_family = family;
     bindhints.ai_flags = AI_PASSIVE;
     if (localaddr) {
         err = inet_trybind(&tcp->sock, localaddr, localserv, &bindhints);
@@ -450,6 +452,7 @@ static int global_connect6(lua_State *L) {
             lua_pushstring(L, err);
             return 2;
         }
+        tcp->family = bindhints.ai_family;
     }
     /* try to connect to remote address and port */
     memset(&connecthints, 0, sizeof(connecthints));

src/usocket.c

@@ -447,7 +447,7 @@ const char *socket_gaistrerror(int err) {
         case EAI_SERVICE: return "service not supported for socket type";
         case EAI_SOCKTYPE: return "ai_socktype not supported";
         case EAI_SYSTEM: return strerror(errno); 
-        default: return "unknown error";
+        default: return gai_strerror(err);
     }
 }