in bitcoin 0.10 and the net.cpp, i don't koow how ThreadOpenConnectionswork,because the red code is a inite loop , so why it can excute the next code
void ThreadOpenConnections()
{
// Connect to specific addresses
if (mapArgs.count("-connect") && mapMultiArgs["-connect"].size() > 0)
{
for (int64_t nLoop = 0;; nLoop++)
{
ProcessOneShot();
BOOST_FOREACH(string strAddr, mapMultiArgs["-connect"])
{
CAddress addr;
OpenNetworkConnection(addr, NULL, strAddr.c_str());
for (int i = 0; i < 10 && i < nLoop; i++)
{
MilliSleep(500);
}
}
MilliSleep(500);
}
}
// Initiate network connections
int64_t nStart = GetTime();
while (true)
{
ProcessOneShot();
MilliSleep(500);
CSemaphoreGrant grant(*semOutbound);
boost::this_thread::interruption_point();
// Add seed nodes if DNS seeds are all down (an infrastructure attack?).
if (addrman.size() == 0 && (GetTime() - nStart > 60)) {
static bool done = false;
if (!done) {
LogPrintf("Adding fixed seed nodes as DNS doesn't seem to be available.\n");
addrman.Add(Params().FixedSeeds(), CNetAddr("127.0.0.1"));
done = true;
}
}
//
// Choose an address to connect to based on most recently seen
//
CAddress addrConnect;
// Only connect out to one peer per network group (/16 for IPv4).
// Do this here so we don't have to critsect vNodes inside mapAddresses critsect.
int nOutbound = 0;
set > setConnected;
{
LOCK(cs_vNodes);
BOOST_FOREACH(CNode* pnode, vNodes) {
if (!pnode->fInbound) {
setConnected.insert(pnode->addr.GetGroup());
nOutbound++;
}
}
}
int64_t nANow = GetAdjustedTime();
int nTries = 0;
while (true)
{
CAddress addr = addrman.Select();
// if we selected an invalid address, restart
if (!addr.IsValid() || setConnected.count(addr.GetGroup()) || IsLocal(addr))
break;
// If we didn't find an appropriate destination after trying 100 addresses fetched from addrman,
// stop this loop, and let the outer loop run again (which sleeps, adds seed nodes, recalculates
// already-connected network ranges, ...) before trying new addrman addresses.
nTries++;
if (nTries > 100)
break;
if (IsLimited(addr))
continue;
// only consider very recently tried nodes after 30 failed attempts
if (nANow - addr.nLastTry < 600 && nTries < 30)
continue;
// do not allow non-default ports, unless after 50 invalid addresses selected already
if (addr.GetPort() != Params().GetDefaultPort() && nTries < 50)
continue;
addrConnect = addr;
break;
}
if (addrConnect.IsValid())
OpenNetworkConnection(addrConnect, &grant);
}
}