Forward-port poll socket engine as it seems reasonably stable, and half-hack it into configure. If someone could help me (easily) add it via our wonderful configure macros so it's built, that would be swell.

git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@10264 e03df62e-2008-0410-955e-edbf42e46eb7

configure

@@ -275,6 +275,7 @@ if (defined $opt_nokqueue)
 {
 	$config{USE_KQUEUE} = "n";
 }
+$config{USE_POLL}     = "y";					# poll enabled
 $config{USE_EPOLL}	  = "y";					# epoll enabled
 if (defined $opt_epoll)
 {
@@ -801,22 +802,36 @@ should NOT be used. You should probably specify a newer compiler.\n\n";
 	dir_check("is the IRCd binary to be placed", "BINARY_DIR");
 	dir_check("are the IRCd libraries to be placed", "LIBRARY_DIR");
 
+	my $chose_hiperf = 0;
 	if ($has_kqueue) {
 		yesno('USE_KQUEUE',"You are running a BSD operating system, and kqueue\nwas detected. Would you like to enable kqueue support?\nThis is likely to increase performance.\nIf you are unsure, answer yes.\n\nEnable kqueue?");
 		print "\n";
+		if ($config{USE_KQUEUE} eq "y") {
+			$chose_hiperf = 1;
+		}
 	}
 	if ($has_epoll) {
 		yesno('USE_EPOLL',"You are running a Linux 2.6+ operating system, and epoll\nwas detected. Would you like to enable epoll support?\nThis is likely to increase performance.\nIf you are unsure, answer yes.\n\nEnable epoll?");
 		print "\n";
+		if ($config{USE_EPOLL} eq "y") {
+			$chose_hiperf = 1;
+		}
 	}
 	if ($has_ports) {
 		yesno('USE_PORTS',"You are running Solaris 10.\nWould you like to enable I/O completion ports support?\nThis is likely to increase performance.\nIf you are unsure, answer yes.\n\nEnable support for I/O completion ports?");
 		print "\n";
+		if ($config{USE_PORTS} eq "y") {
+			$chose_hiperf = 1;
+		}
 	}
-	my $chose_hiperf = (($config{USE_EPOLL} eq "y") || ($config{USE_KQUEUE} eq "y") || ($config{USE_PORTS} eq "y"));
+
 	if (!$chose_hiperf) {
-		print "No high-performance socket engines are available, or you chose\n";
-		print "not to enable one. Defaulting to select() engine.\n\n";
+		yesno('USE_POLL', "Would you like to use poll?\n This is likely to increase performance.\nIf you are unsure, answer yes.\n\nEnable poll?\n");
+		if ($config{USE_POLL} ne "y")
+		{
+			print "No high-performance socket engines are available, or you chose\n";
+			print "not to enable one. Defaulting to select() engine.\n\n";
+		}
 	}
 
 	yesno('IPV6',"Would you like to build InspIRCd with IPv6 support?");
@@ -1221,8 +1236,17 @@ print FILEHANDLE "#define MAXBUF " . ($config{MAXBUF}+2) . "\n";
 		# user didn't choose either epoll or select for their OS.
 		# default them to USE_SELECT (ewwy puke puke)
 		if (!$use_hiperf) {
-			print FILEHANDLE "#define USE_SELECT\n";
-			$se = "socketengine_select";
+			print "no hi-perf, " . $config{USE_POLL};
+			if ($config{USE_POLL} eq "y")
+			{
+				print FILEHANDLE "#define USE_POLL\n";
+				$se = "socketengine_poll";
+			}
+			else
+			{
+				print FILEHANDLE "#define USE_SELECT\n";
+				$se = "socketengine_select";
+			}
 		}
 		print FILEHANDLE "\n#include \"threadengines/threadengine_pthread.h\"\n\n#endif\n";
 		close(FILEHANDLE);

include/socketengines/socketengine_poll.h

@@ -0,0 +1,66 @@
+/*       +------------------------------------+
+ *       | Inspire Internet Relay Chat Daemon |
+ *       +------------------------------------+
+ *
+ *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
+ * See: http://www.inspircd.org/wiki/index.php/Credits
+ *
+ * This program is free but copyrighted software; see
+ *            the file COPYING for details.
+ *
+ * ---------------------------------------------------
+ */
+
+#ifndef __SOCKETENGINE_POLL__
+#define __SOCKETENGINE_POLL__
+
+#include <vector>
+#include <string>
+#include <map>
+#include "inspircd_config.h"
+#include "globals.h"
+#include "inspircd.h"
+#include "socketengine.h"
+#ifndef __USE_XOPEN
+        #define __USE_XOPEN /* fuck every fucking OS ever made. needed by poll.h to work.*/
+#endif
+#include <poll.h>
+
+class InspIRCd;
+
+/** A specialisation of the SocketEngine class, designed to use poll().
+ */
+class PollEngine : public SocketEngine
+{
+private:
+	/** These are used by poll() to hold socket events
+	 */
+	struct pollfd *events;
+public:
+	/** Create a new PollEngine
+	 * @param Instance The creator of this object
+	 */
+	PollEngine(InspIRCd* Instance);
+	/** Delete a PollEngine
+	 */
+	virtual ~PollEngine();
+	virtual bool AddFd(EventHandler* eh);
+	virtual int GetMaxFds();
+	virtual int GetRemainingFds();
+	virtual bool DelFd(EventHandler* eh, bool force = false);
+	virtual int DispatchEvents();
+	virtual std::string GetName();
+	virtual void WantWrite(EventHandler* eh);
+};
+
+/** Creates a SocketEngine
+ */
+class SocketEngineFactory
+{
+public:
+	/** Create a new instance of SocketEngine based on PollEngine
+	 */
+	SocketEngine* Create(InspIRCd* Instance) { return new PollEngine(Instance); }
+};
+
+#endif

src/socketengines/socketengine_epoll.cpp

@@ -13,7 +13,6 @@
 
 #include "inspircd.h"
 #include "exitcodes.h"
-#include <sys/epoll.h>
 #include "socketengines/socketengine_epoll.h"
 #include <ulimit.h>
 

src/socketengines/socketengine_poll.cpp

@@ -0,0 +1,180 @@
+/*       +------------------------------------+
+ *       | Inspire Internet Relay Chat Daemon |
+ *       +------------------------------------+
+ *
+ *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
+ * See: http://www.inspircd.org/wiki/index.php/Credits
+ *
+ * This program is free but copyrighted software; see
+ *            the file COPYING for details.
+ *
+ * ---------------------------------------------------
+ */
+
+#include "inspircd.h"
+#include "exitcodes.h"
+#include "socketengines/socketengine_poll.h"
+
+PollEngine::PollEngine(InspIRCd* Instance) : SocketEngine(Instance)
+{
+	// Poll requires no special setup (which is nice).
+	CurrentSetSize = 0;
+
+	ref = new EventHandler* [GetMaxFds()];
+	events = new struct epoll_event[GetMaxFds()];
+
+	memset(&events, 0, GetMaxFds() * sizeof(struct pollfds*));
+}
+
+PollEngine::~PollEngine()
+{
+	// No destruction required, either.
+	delete[] ref;
+	delete[] events;
+}
+
+bool PollEngine::AddFd(EventHandler* eh)
+{
+	int fd = eh->GetFd();
+	if ((fd < 0) || (fd > GetMaxFds() - 1))
+	{
+		ServerInstance->Logs->Log("SOCKET",DEBUG,"AddFd out of range: (fd: %d, max: %d)", fd, GetMaxFds());
+		return false;
+	}
+
+	if (GetRemainingFds() <= 1)
+	{
+		ServerInstance->Logs->Log("SOCKET",DEBUG,"No remaining FDs cannot add fd: %d", fd);
+		return false;
+	}
+
+	if (ref[fd])
+	{
+		ServerInstance->Logs->Log("SOCKET",DEBUG,"Attempt to add duplicate fd: %d", fd);
+		return false;
+	}
+
+	ref[fd] = eh;
+	events[fd]->fd = fd;
+	if (eh->Readable())
+	{
+		events[fd]->events = POLLIN;
+	}
+	else
+	{
+		events[fd]->events = POLLOUT;
+	}
+
+	ServerInstance->Log(DEBUG,"New file descriptor: %d (%d)", fd, events[fd]->events);
+	CurrentSetSize++;
+	return true;
+}
+
+void PollEngine::WantWrite(EventHandler* eh)
+{
+	events[eh->GetFd()]->events = POLLIN | POLLOUT;
+}
+
+bool PollEngine::DelFd(EventHandler* eh, bool force)
+{
+	int fd = eh->GetFd();
+	if ((fd < 0) || (fd > MAX_DESCRIPTORS))
+	{
+		ServerInstance->Logs->Log("SOCKET",DEBUG,"DelFd out of range: (fd: %d, max: %d)", fd, GetMaxFds());
+		return false;
+	}
+
+	events[fd]->fd = -1;
+	events[fd]->events = 0;
+
+	CurrentSetSize--;
+	ref[fd] = NULL;
+
+	ServerInstance->Log(DEBUG,"Remove file descriptor: %d", fd);
+	return true;
+}
+
+int PollEngine::GetMaxFds()
+{
+	if (MAX_DESCRIPTORS)
+		return MAX_DESCRIPTORS;
+
+	int max = ulimit(4, 0);
+	if (max > 0)
+	{
+		MAX_DESCRIPTORS = max;
+		return max;
+	}
+	else
+	{
+		ServerInstance->Logs->Log("SOCKET", DEFAULT, "ERROR: Can't determine maximum number of open sockets!");
+		printf("ERROR: Can't determine maximum number of open sockets!\n");
+		ServerInstance->Exit(EXIT_STATUS_SOCKETENGINE);
+	}
+	return 0;
+}
+
+int PollEngine::GetRemainingFds()
+{
+	return MAX_DESCRIPTORS - CurrentSetSize;
+}
+
+int PollEngine::DispatchEvents()
+{
+	int i = poll(events, GetMaxFds() - 1, 1000);
+	int fd = 0;
+	socklen_t codesize = sizeof(int);
+	int errcode;
+	int processed = 0;
+
+	if (i > 0)
+	{
+		for (fd = 0; fd < GetMaxFds() - 1 && processed != i; fd++)
+		{
+			if (events[fd].revents)
+				processed++;
+
+			if (events[fd].revents & POLLHUP)
+			{
+				if (ref[fd])
+					ref[fd]->HandleEvent(EVENT_ERROR, 0);
+				continue;
+			}
+
+			if (events[fd].revents & POLLERR)
+			{
+				// Get error number
+				if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &errcode, &codesize) < 0)
+					errcode = errno;
+				if (ref[fd])
+					ref[fd]->HandleEvent(EVENT_ERROR, errcode);
+				continue;
+			}
+
+			if (events[fd].revents & POLLOUT)
+			{
+				// Switch to wanting read again
+				// event handlers have to request to write again if they need it
+				events[fd].events = POLLIN;
+
+
+				if (ref[fd])
+					ref[fd]->HandleEvent(EVENT_WRITE);
+			}
+
+			if (events[fd].revents & POLLIN)
+			{
+				if (ref[fd])
+					ref[fd]->HandleEvent(EVENT_READ);
+			}
+		}
+	}
+
+	return i;
+}
+
+std::string PollEngine::GetName()
+{
+	return "poll";
+}
+