/*
simgear::Socket, adapted from PLIB Socket by James Turner
Copyright (C) 2010 James Turner
-
+
PLIB - A Suite of Portable Game Libraries
Copyright (C) 1998,2002 Steve Baker
-
+
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
-
+
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
-
+
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#include <errno.h>
#if defined(WINSOCK)
-# include <winsock.h>
+# include <winsock2.h>
+# include <ws2tcpip.h>
# include <stdarg.h>
#else
# include <sys/types.h>
# include <sys/socket.h>
# include <netinet/in.h>
# include <arpa/inet.h>
-# include <sys/time.h>
+# include <sys/time.h>
# include <unistd.h>
# include <netdb.h>
# include <fcntl.h>
#define socklen_t int
#endif
+#include <map>
+
#include <simgear/debug/logstream.hxx>
#include <simgear/structure/exception.hxx>
+#include <simgear/threads/SGThread.hxx>
+
+namespace {
+
+class Resolver : public SGThread
+{
+public:
+ static Resolver* instance()
+ {
+ if (!static_instance) {
+ static_instance = new Resolver;
+ atexit(&Resolver::cleanup);
+ static_instance->start();
+ }
+
+ return static_instance;
+ }
+
+ static void cleanup()
+ {
+ static_instance->shutdown();
+ static_instance->join();
+ }
+
+ Resolver() :
+ _done(false)
+ {
+ }
+
+ void shutdown()
+ {
+ _lock.lock();
+ _done = true;
+ _wait.signal();
+ _lock.unlock();
+ }
+
+ simgear::IPAddress* lookup(const string& host)
+ {
+ simgear::IPAddress* result = NULL;
+ _lock.lock();
+ AddressCache::iterator it = _cache.find(host);
+ if (it == _cache.end()) {
+ _cache[host] = NULL; // mark as needing looked up
+ _wait.signal(); // if the thread was sleeping, poke it
+ } else {
+ result = it->second;
+ }
+ _lock.unlock();
+ return result;
+ }
+
+ simgear::IPAddress* lookupSync(const string& host)
+ {
+ simgear::IPAddress* result = NULL;
+ _lock.lock();
+ AddressCache::iterator it = _cache.find(host);
+ if (it == _cache.end()) {
+ _lock.unlock();
+ result = new simgear::IPAddress;
+ bool ok = lookupHost(host.c_str(), *result);
+ _lock.lock();
+ if (ok) {
+ _cache[host] = result; // mark as needing looked up
+ } else {
+ delete result;
+ result = NULL;
+ }
+ } else { // found in cache, easy
+ result = it->second;
+ }
+ _lock.unlock();
+ return result;
+ }
+protected:
+ /**
+ * run method waits on a condition (_wait), and when awoken,
+ * finds any unresolved entries in _cache, resolves them, and goes
+ * back to sleep.
+ */
+ virtual void run()
+ {
+ _lock.lock();
+ while (!_done) {
+ AddressCache::iterator it;
+
+ for (it = _cache.begin(); it != _cache.end(); ++it) {
+ if (it->second == NULL) {
+ string h = it->first;
+
+ _lock.unlock();
+ simgear::IPAddress* addr = new simgear::IPAddress;
+ // may take seconds or even minutes!
+ lookupHost(h.c_str(), *addr);
+ _lock.lock();
+
+ // cahce may have changed while we had the lock released -
+ // so iterators may be invalid: restart the traversal
+ it = _cache.begin();
+ _cache[h] = addr;
+ } // of found un-resolved entry
+ } // of un-resolved address iteration
+ _wait.wait(_lock);
+ } // of thread run loop
+ _lock.unlock();
+ }
+private:
+ static Resolver* static_instance;
+
+ /**
+ * The actual synchronous, blocking host lookup function
+ * do *not* call this with any locks (mutexs) held, since depending
+ * on local system configuration / network availability, it
+ * may block for seconds or minutes.
+ */
+ bool lookupHost(const char* host, simgear::IPAddress& addr)
+ {
+ struct addrinfo hints;
+ memset(&hints, 0, sizeof(struct addrinfo));
+ hints.ai_family = AF_INET;
+ bool ok = false;
+
+ struct addrinfo* result0 = NULL;
+ int err = getaddrinfo(host, NULL, &hints, &result0);
+ if (err) {
+ SG_LOG(SG_IO, SG_WARN, "getaddrinfo failed for '" << host << "' : " << gai_strerror(err));
+ return false;
+ } else {
+ struct addrinfo* result;
+ for (result = result0; result != NULL; result = result->ai_next) {
+ if (result->ai_family != AF_INET) { // only accept IP4 for the moment
+ continue;
+ }
+
+ if (result->ai_addrlen != addr.getAddrLen()) {
+ SG_LOG(SG_IO, SG_ALERT, "mismatch in socket address sizes: got " <<
+ result->ai_addrlen << ", expected " << addr.getAddrLen());
+ continue;
+ }
+
+ memcpy(addr.getAddr(), result->ai_addr, result->ai_addrlen);
+ ok = true;
+ break;
+ } // of getaddrinfo results iteration
+ } // of getaddrinfo succeeded
+
+ freeaddrinfo(result0);
+ return ok;
+ }
+
+ SGMutex _lock;
+ SGWaitCondition _wait;
+
+ typedef std::map<string, simgear::IPAddress*> AddressCache;
+ AddressCache _cache;
+ bool _done;
+};
+
+Resolver* Resolver::static_instance = NULL;
+
+} // of anonymous namespace
namespace simgear
{
-
+
IPAddress::IPAddress ( const char* host, int port )
{
set ( host, port ) ;
addr->sin_addr.s_addr = INADDR_ANY;
return;
}
-
+
if (strcmp(host, "<broadcast>") == 0) {
addr->sin_addr.s_addr = INADDR_BROADCAST;
return;
}
-
- struct addrinfo* result = NULL;
- int err = getaddrinfo(host, NULL, NULL /* no hints */, &result);
- if (err) {
- SG_LOG(SG_IO, SG_WARN, "getaddrinfo failed for '" << host << "' : " << gai_strerror(err));
- } else if (result->ai_addrlen != getAddrLen()) {
- SG_LOG(SG_IO, SG_ALERT, "mismatch in socket address sizes");
- } else {
- memcpy(addr, result->ai_addr, result->ai_addrlen);
+
+// check the cache
+ IPAddress* cached = Resolver::instance()->lookupSync(host);
+ if (cached) {
+ memcpy(addr, cached->getAddr(), cached->getAddrLen());
}
-
- freeaddrinfo(result);
+
addr->sin_port = htons (port); // fix up port after getaddrinfo
}
}
}
+bool IPAddress::lookupNonblocking(const char* host, IPAddress& addr)
+{
+ IPAddress* cached = Resolver::instance()->lookup(host);
+ if (!cached) {
+ return false;
+ }
+
+ addr = *cached;
+ return true;
+}
+
/* Create a string object representing an IP address.
This is always a string of the form 'dd.dd.dd.dd' (with variable
size numbers). */
const char* IPAddress::getHost () const
{
+ if (!addr) {
+ return NULL;
+ }
+
static char buf [32];
long x = ntohl(addr->sin_addr.s_addr);
sprintf(buf, "%d.%d.%d.%d",
return buf;
}
-unsigned int IPAddress::getIP () const
-{
- return addr->sin_addr.s_addr;
+unsigned int IPAddress::getIP () const
+{
+ if (!addr) {
+ return 0;
+ }
+
+ return addr->sin_addr.s_addr;
}
unsigned int IPAddress::getPort() const
{
+ if (!addr) {
+ return 0;
+ }
+
return ntohs(addr->sin_port);
}
-unsigned int IPAddress::getFamily () const
-{
- return addr->sin_family;
+void IPAddress::setPort(int port)
+{
+ if (!addr) {
+ return;
+ }
+
+ addr->sin_port = htons(port);
+}
+
+unsigned int IPAddress::getFamily () const
+{
+ if (!addr) {
+ return 0;
+ }
+
+ return addr->sin_family;
}
const char* IPAddress::getLocalHost ()
bool IPAddress::getBroadcast () const
{
- return (addr->sin_addr.s_addr == INADDR_BROADCAST);
+ if (!addr) {
+ return false;
+ }
+
+ return (addr->sin_addr.s_addr == INADDR_BROADCAST);
}
unsigned int IPAddress::getAddrLen() const
struct sockaddr* IPAddress::getAddr() const
{
+ if (addr == NULL) {
+ addr = (struct sockaddr_in*) malloc(sizeof(struct sockaddr_in));
+ memset(addr, 0, sizeof(struct sockaddr_in));
+ }
+
return (struct sockaddr*) addr;
}
+bool IPAddress::isValid() const
+{
+ return (addr != NULL);
+}
+
Socket::Socket ()
{
handle = -1 ;
} else {
result = ::setsockopt( handle, SOL_SOCKET, SO_BROADCAST, NULL, 0 );
}
-
+
if ( result < 0 ) {
throw sg_exception("Socket::setBroadcast failed");
}
}
#endif
- // 224.0.0.0 - 239.255.255.255 are multicast
+ // 224.0.0.0 - 239.255.255.255 are multicast
// Usage of 239.x.x.x is recommended for local scope
// Reference: http://tools.ietf.org/html/rfc5771
if( ntohl(addr.getIP()) >= 0xe0000000 && ntohl(addr.getIP()) <= 0xefffffff ) {
a.sin_addr.S_un.S_addr = INADDR_ANY;
a.sin_family = AF_INET;
a.sin_port = htons(port);
-
+
if( (result = ::bind(handle,(const sockaddr*)&a,sizeof(a))) < 0 ) {
SG_LOG(SG_IO, SG_ALERT, "bind(any:" << port << ") failed. Errno " << errno << " (" << strerror(errno) << ")");
return result;
}
}
#if defined(WINSOCK)
- else if( (result = ::bind(handle,addr->getAddr(), addr->getAddrLen())) < 0 ) {
+ else if( (result = ::bind(handle,addr.getAddr(), addr.getAddrLen())) < 0 ) {
SG_LOG(SG_IO, SG_ALERT, "bind(" << host << ":" << port << ") failed. Errno " << errno << " (" << strerror(errno) << ")");
return result;
}
{
fd_set r,w;
int retval;
-
+
FD_ZERO (&r);
FD_ZERO (&w);
// It bothers me that select()'s first argument does not appear to
// work as advertised... [it hangs like this if called with
// anything less than FD_SETSIZE, which seems wasteful?]
-
+
// Note: we ignore the 'exception' fd_set - I have never had a
// need to use it. The name is somewhat misleading - the only
// thing I have ever seen it used for is to detect urgent data -