/* lsocket_sock_recvfrom
*
* reads data from a socket
*
* Arguments:
* L Lua State
*
* Lua Stack:
* 1 the lSocket userdata
* 2 (optional) the length of the buffer to use for reading, defaults
* to some internal value
*
* Lua Returns:
* +1 a string containing the data read
* +2 ip address if remote end
* +3 port of remote end
* or +1 false if nonblocking socket returned EAGAIN (no data available)
* or +1 nil if the remote end has closed the socket
* or +1 nil, +2 error message on error
*/
static int lsocket_sock_recvfrom(lua_State *L)
{
lSocket *sock = lsocket_checklSocket(L, 1);
uint32_t howmuch = luaL_optnumber(L, 2, READER_BUFSIZ);
if (lua_tonumber(L, 2) > UINT_MAX)
return luaL_error(L, "bad argument #1 to 'recvfrom' (invalid number)");
char sabuf[sizeof(struct sockaddr_in6)];
struct sockaddr *sa = (struct sockaddr*) sabuf;
socklen_t slen = sizeof(sabuf);
char *buf = malloc(howmuch);
int nrd = recvfrom(sock->sockfd, buf, howmuch, 0, sa, &slen);
if (nrd < 0) {
free(buf);
if (errno == EAGAIN || errno == EWOULDBLOCK)
lua_pushboolean(L, 0);
else
return lsocket_error(L, strerror(errno));
} else if (nrd == 0)
lua_pushnil(L); /* not possible for udp, so should not get here */
else {
lua_pushlstring(L, buf, nrd);
free(buf);
char ipbuf[TOSTRING_BUFSIZ];
const char *s = _addr2string(sa, ipbuf, TOSTRING_BUFSIZ);
if (s)
lua_pushstring(L, s);
else
return lsocket_error(L, strerror(errno)); /* should not happen */
lua_pushnumber(L, _portnumber(sa));
return 3;
}
return 1;
}
/* lsocket_sock_accept
*
* accept a new connection on a socket
*
* Arguments:
* L Lua State
*
* Lua Stack:
* 1 the lSocket userdata
*
* Lua Returns:
* +1 new socket, +2 client ip, +3 client port on success
* or +1 false if nonblocking socket returned EAGAIN
* or +1 nil, +2 error message on error
*/
static int lsocket_sock_accept(lua_State *L)
{
lSocket *sock = lsocket_checklSocket(L, 1);
char buf[TOSTRING_BUFSIZ];
if (!_canacceptdata(sock->sockfd, 0)) {
lua_pushboolean(L, 0);
return 1;
}
char sabuf[sizeof(struct sockaddr_in6)];
struct sockaddr *sa = (struct sockaddr*) sabuf;
socklen_t slen = sizeof(sabuf);
int newfd = accept(sock->sockfd, sa, &slen);
if (newfd < 0)
return lsocket_error(L, strerror(errno));
lSocket *nsock = lsocket_pushlSocket(L);
nsock->sockfd = newfd;
if (_initsocket(nsock, sa->sa_family, sock->type, sock->mcast, sock->protocol, 0) == -1)
return lsocket_error(L, strerror(errno));
lua_pushstring(L, _addr2string(sa, buf, TOSTRING_BUFSIZ));
lua_pushnumber(L, _portnumber(sa));
return 3;
}
// deprecated: may hang up, use dns.resolve for cooperative dns query
static int
_resolve(lua_State *L) {
const char* host = luaL_checkstring(L, 1);
struct addrinfo *res = 0;
int err, i;
char buf[sizeof(struct in6_addr)];
struct addrinfo hints;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
err = getaddrinfo(host, NULL, &hints, &res);
if(err != 0) {
lua_pushnil(L);
lua_pushinteger(L, err);
return 2;
}
i = 1;
lua_newtable(L);
while(res) {
// ignore all unsupported address
if((res->ai_family == AF_INET || res->ai_family == AF_INET6) && res->ai_socktype == SOCK_STREAM) {
lua_createtable(L, 0, 2);
lua_pushinteger(L, res->ai_family);
lua_setfield(L, -2, "family");
lua_pushstring(L, _addr2string(res->ai_addr, buf, sizeof(buf)));
lua_setfield(L, -2, "addr");
lua_rawseti(L, -2, i++);
}
res = res->ai_next;
}
return 1;
}
/* lsocket_getinterfaces
*
* enumerates all available interfaces
*
* Arguments:
* L lua State
*
* Lua Stack:
* -
*
* Lua Returns:
* +1 a table with information on all available interfaces. For each
* interface, a subtable is returned with the fields name, family,
* address and mask
*/
static int lsocket_getinterfaces(lua_State *L)
{
struct ifaddrs *ifa;
char buf[TOSTRING_BUFSIZ];
const char *s;
int i = 1;
if (getifaddrs(&ifa) < 0)
return lsocket_error(L, strerror(errno));
lua_newtable(L);
while (ifa) {
lua_newtable(L);
lua_pushliteral(L, "name");
lua_pushstring(L, ifa->ifa_name);
lua_rawset(L, -3);
s = _addr2string(ifa->ifa_addr, buf, TOSTRING_BUFSIZ);
if (s) {
lua_pushliteral(L, "family");
lua_pushstring(L, ifa->ifa_addr->sa_family == AF_INET ? LSOCKET_INET : LSOCKET_INET6);
lua_rawset(L, -3);
lua_pushliteral(L, "addr");
lua_pushstring(L, s);
lua_rawset(L, -3);
s = _addr2string(ifa->ifa_netmask, buf, TOSTRING_BUFSIZ);
if (s) {
lua_pushliteral(L, "mask");
lua_pushstring(L, s);
lua_rawset(L, -3);
}
lua_rawseti(L, -2, i++);
} else
lua_pop(L, 1);
ifa = ifa->ifa_next;
}
freeifaddrs(ifa);
return 1;
}
/* _push_sockname
*
* helper for lsocket_sock_info: create a table with fields port, family
* and addr from the sockaddr passed as argument, and leave it on the
* stack. Leave nil on error.
*
* Arguments:
* L Lua State
* sa pointer to sockaddr to get data from
*
* Lua Returns:
* +1 table with info about address, or nil
*/
static void _push_sockname(lua_State *L, struct sockaddr *sa)
{
char buf[TOSTRING_BUFSIZ];
const char *s;
lua_newtable(L);
lua_pushliteral(L, "port");
lua_pushnumber(L, _portnumber(sa));
lua_rawset(L, -3);
lua_pushliteral(L, "family");
lua_pushstring(L, sa->sa_family == AF_INET ? LSOCKET_INET : LSOCKET_INET6);
lua_rawset(L, -3);
lua_pushliteral(L, "addr");
s = _addr2string(sa, buf, TOSTRING_BUFSIZ);
if (s) {
lua_pushstring(L, s);
lua_rawset(L, -3);
} else {
lua_pop(L, 1);
}
}
/* lsocket_resolve
*
* resolves a name to an address
*
* Arguments:
* L lua State
*
* Lua Stack:
* 1 name of host to resolve
*
* Lua Returns:
* +1 a table of all addresses the argument resolves to. For each address,
* a subtable with the fields family and addr is created.
*/
static int lsocket_resolve(lua_State *L)
{
const char *name = luaL_checkstring(L, 1);
char buf[TOSTRING_BUFSIZ];
struct addrinfo hint, *info =0;
memset(&hint, 0, sizeof(hint));
hint.ai_family = AF_UNSPEC;
if (_needsnolookup(name))
hint.ai_flags = AI_NUMERICHOST;
int err = getaddrinfo(name, 0, &hint, &info);
if (err != 0) {
if (info) freeaddrinfo(info);
return lsocket_error(L, gai_strerror(err));
}
int i = 1;
lua_newtable(L);
while (info) {
if (info->ai_family == AF_INET || info->ai_family == AF_INET6) {
lua_newtable(L);
lua_pushliteral(L, "family");
lua_pushstring(L, info->ai_family == AF_INET ? LSOCKET_INET : LSOCKET_INET6);
lua_rawset(L, -3);
lua_pushliteral(L, "addr");
lua_pushstring(L, _addr2string(info->ai_addr, buf, TOSTRING_BUFSIZ));
lua_rawset(L, -3);
lua_rawseti(L, -2, i++);
info = info->ai_next;
}
/* silently ignore unknown address families */
}
freeaddrinfo(info);
return 1;
}
