* | Inspire Internet Relay Chat Daemon |
* +------------------------------------+
*
- * Inspire is copyright (C) 2002-2005 ChatSpike-Dev.
- * E-mail:
- * <brain@chatspike.net>
- * <Craig@chatspike.net>
+ * InspIRCd: (C) 2002-2009 InspIRCd Development Team
+ * See: http://wiki.inspircd.org/Credits
*
- * Written by Craig Edwards, Craig McLure, and others.
* This program is free but copyrighted software; see
* the file COPYING for details.
*
* ---------------------------------------------------
*/
-// Fill the engine with client file descriptors pending an action
-
-#define epoll_fill int i = epoll_wait(ep, event, 1, 5); \
- if (i > 0) \
- { \
- log(DEBUG,"epoll_wait call: ep=%d, i=%d",ep,i); \
- userrec* cu = fd_ref_table[event[0].data.fd];
-
-#define kqueue_fill ts.tv_sec = 0; \
- ts.tv_nsec = 1000L; \
- int i = kevent(kq, NULL, 0, &ke, 1, &ts); \
- if (i > 0) \
- { \
- log(DEBUG,"kevent call: kq=%d, i=%d",kq,i); \
- userrec* cu = fd_ref_table[ke.ident];
-
-#define select_fill tval.tv_sec = 0; \
- tval.tv_usec = 1000L; \
- selectResult2 = select(FD_SETSIZE, &sfd, NULL, NULL, &tval); \
- if ((selectResult2 > 0) && (xcount != clientlist.end())) \
- for (user_hash::iterator count2a = xcount; count2a != endingiter; count2a++) \
- { \
- if (count2a == clientlist.end()) \
- break; \
- userrec* cu = count2a->second;
-
-#ifdef USE_EPOLL
-#define engine_fill epoll_fill
-#endif
-#ifdef USE_KQUEUE
-#define engine_fill kqueue_fill
-#endif
-#ifdef USE_SELECT
-#define engine_fill select_fill
-#endif
-
-// how to determine if a socket needs attention if further checks are needed
-
-#define epoll_check ((cu->fd != FD_MAGIC_NUMBER) && (cu->fd != -1))
-
-#define kqueue_check ((cu->fd != FD_MAGIC_NUMBER) && (cu->fd != -1))
-
-#define select_check ((cu->fd != FD_MAGIC_NUMBER) && (cu->fd != -1) && (FD_ISSET (cu->fd, &sfd)))
-
-#ifdef USE_EPOLL
-#define engine_check epoll_check
-#endif
-#ifdef USE_KQUEUE
-#define engine_check kqueue_check
-#endif
-#ifdef USE_SELECT
-#define engine_check select_check
-#endif
-
-// how to clean up an exiting client
-
-#define epoll_cleanup log(DEBUG,"InspIRCd: Exited: %s",cu->nick); \
- kill_link(cu,"Client exited"); \
- log(DEBUG,"Bailing from client exit"); \
- goto label;
-
-#define kqueue_cleanup log(DEBUG,"InspIRCd: Exited: %s",cu->nick); \
- kill_link(cu,"Client exited"); \
- log(DEBUG,"Bailing from client exit"); \
- goto label;
-
-#define select_cleanup if (count2->second) \
- { \
- log(DEBUG,"InspIRCd: Exited: %s",cu->nick); \
- kill_link(cu,"Client exited"); \
- log(DEBUG,"Bailing from client exit"); \
- goto label; \
- }
-
-#ifdef USE_EPOLL
-#define engine_cleanup epoll_cleanup
-#endif
-#ifdef USE_KQUEUE
-#define engine_cleanup kqueue_cleanup
-#endif
-#ifdef USE_SELECT
-#define engine_cleanup select_cleanup
-#endif
-
-
-// how to scan the set for fd's requiring action
-
-#define select_scanset for (count = 0; count < boundPortCount; count++) \
- { \
- FD_SET (openSockfd[count], &selectFds); \
- } \
- tv.tv_usec = 30000L; \
- selectResult = select(MAXSOCKS, &selectFds, NULL, NULL, &tv); \
- if (selectResult > 0) \
- { \
- for (count = 0; count < boundPortCount; count++) \
- { \
- if (FD_ISSET (openSockfd[count], &selectFds)) \
- {
-
-#define kqueue_scanset ts.tv_sec = 0; \
- ts.tv_nsec = 30000L; \
- i = kevent(lkq, NULL, 0, ke_list, 32, &ts); \
- if (i > 0) for (j = 0; j < i; j++) \
- { \
- log(DEBUG,"kqueue: Listening socket event, i=%d, ke.ident=%d",i,ke_list[j].ident); \
- for (count = 0; count < boundPortCount; count++) \
- { \
- if ((unsigned)ke_list[j].ident == (unsigned)openSockfd[count]) \
- {
-
-#define epoll_scanset i = epoll_wait(lep, event, 32, EP_DELAY); \
- if (i > 0) for (j = 0; j < i; j++) \
- { \
- log(DEBUG,"epoll: Listening socket event, i=%d,events[j].data.fd=%d",i,event[j].data.fd); \
- for (count = 0; count < boundPortCount; count++) \
- { \
- if ((unsigned)event[j].data.fd == (unsigned)openSockfd[count]) \
- {
-
-#ifdef USE_EPOLL
-#define engine_scanset epoll_scanset
-#endif
-#ifdef USE_KQUEUE
-#define engine_scanset kqueue_scanset
-#endif
-#ifdef USE_SELECT
-#define engine_scanset select_scanset
-#endif
-
-// a list of variables used specifically by this engine
-
-#define kqueue_structs struct kevent ke; \
- struct kevent ke_list[33]; \
- struct timespec ts;
-
-#define epoll_structs struct epoll_event event[33];
-
-#define select_structs fd_set sfd;
-
-#ifdef USE_EPOLL
-#define engine_structs epoll_structs
-#endif
-#ifdef USE_KQUEUE
-#define engine_structs kqueue_structs
-#endif
-#ifdef USE_SELECT
-#define engine_structs select_structs
-#endif
-
-// how to initialise the engine before using it
-
-#define select_init while(0);
-
-#define kqueue_init kq = kqueue(); \
- lkq = kqueue(); \
- skq = kqueue(); \
- if ((kq == -1) || (lkq == -1) || (skq == -1)) \
- { \
- log(DEFAULT,"main: kqueue() failed!"); \
- printf("ERROR: could not initialise kqueue event system. Shutting down.\n"); \
- Exit(ERROR); \
- }
-
-#define epoll_init ep = epoll_create(MAXCLIENTS); \
- lep = epoll_create(32); \
- sep = epoll_create(128); \
- if ((ep == -1) || (lep == -1) || (sep == -1)) \
- { \
- log(DEFAULT,"main: epoll_create() failed!"); \
- printf("ERROR: could not initialise epoll event system. Shutting down.\n"); \
- Exit(ERROR); \
- }
-
-
-#ifdef USE_EPOLL
-#define engine_init epoll_init
-#endif
-#ifdef USE_KQUEUE
-#define engine_init kqueue_init
-#endif
-#ifdef USE_SELECT
-#define engine_init select_init
-#endif
-
-// how to delete a client fd from the engine
-
-#define kqueue_delete_fd struct kevent ke; \
- EV_SET(&ke, user->fd, EVFILT_READ, EV_DELETE, 0, 0, NULL); \
- int i = kevent(kq, &ke, 1, 0, 0, NULL); \
- if (i == -1) \
- { \
- log(DEBUG,"kqueue: Failed to remove user from queue!"); \
- }
-
-#define epoll_delete_fd struct epoll_event ev; \
- ev.events = EPOLLIN | EPOLLET; \
- ev.data.fd = user->fd; \
- int i = epoll_ctl(ep, EPOLL_CTL_DEL, user->fd, &ev); \
- if (i < 0) \
- { \
- log(DEBUG,"epoll: List deletion failure!"); \
- }
-
-#define select_delete_fd while(0);
-
-
-#ifdef USE_EPOLL
-#define engine_delete_fd epoll_delete_fd
-#endif
-#ifdef USE_KQUEUE
-#define engine_delete_fd kqueue_delete_fd
-#endif
-#ifdef USE_SELECT
-#define engine_delete_fd select_delete_fd
-#endif
-
-// how to add a client fd to the engine
-
-#define select_add_fd while(0);
-
-#define epoll_add_fd struct epoll_event ev; \
- log(DEBUG,"epoll: Adduser to events, ep=%d socket=%d",ep,socket); \
- ev.events = EPOLLIN | EPOLLET; \
- ev.data.fd = socket; \
- int i = epoll_ctl(ep, EPOLL_CTL_ADD, socket, &ev); \
- if (i < 0) \
- { \
- log(DEBUG,"epoll: List insertion failure!"); \
- }
-
-#define kqueue_add_fd struct kevent ke; \
- log(DEBUG,"kqueue: Add user to events, kq=%d socket=%d",kq,socket);\
- EV_SET(&ke, socket, EVFILT_READ, EV_ADD, 0, 0, NULL); \
- int i = kevent(kq, &ke, 1, 0, 0, NULL); \
- if (i == -1) \
- { \
- log(DEBUG,"kqueue: List insertion failure!"); \
- }
-
-#ifdef USE_EPOLL
-#define engine_add_fd epoll_add_fd
-#endif
-#ifdef USE_KQUEUE
-#define engine_add_fd kqueue_add_fd
-#endif
-#ifdef USE_SELECT
-#define engine_add_fd select_add_fd
-#endif
-
-#define select_server_fill log(DEFAULT,"Using standard select socket engine.");
-
-#define epoll_server_fill log(DEFAULT,"epoll socket engine is enabled. Filling listen list. boundPortcount=%d",boundPortCount); \
- for (count = 0; count < boundPortCount; count++) \
- { \
- struct epoll_event ev; \
- log(DEBUG,"epoll: Add listening socket to events, ep=%d socket=%d",lep,openSockfd[count]); \
- ev.events = EPOLLIN | EPOLLET; \
- ev.data.fd = openSockfd[count]; \
- int i = epoll_ctl(lep, EPOLL_CTL_ADD, openSockfd[count], &ev); \
- if (i < 0) \
- { \
- log(DEFAULT,"main: add listen ports, epoll_ctl failed!"); \
- printf("ERROR: could not initialise listening sockets in epoll list. Shutting down.\n"); \
- Exit(ERROR); \
- } \
- } \
- for (int t = 0; t != SERVERportCount; t++) \
- { \
- struct epoll_event ev; \
- log(DEBUG,"epoll: Add listening server socket to events, ep=%d socket=%d",sep,me[t]->fd); \
- ev.events = EPOLLIN | EPOLLET; \
- ev.data.fd = me[t]->fd; \
- int i = epoll_ctl(sep, EPOLL_CTL_ADD, me[t]->fd, &ev); \
- if (i == -1) \
- { \
- log(DEFAULT,"main: add server listen ports, epoll_ctl failed!"); \
- printf("ERROR: could not initialise server listening sockets in epoll list. Shutting down.\n"); \
- Exit(ERROR); \
- } \
- }
-
-#define kqueue_server_fill log(DEFAULT,"kqueue socket engine is enabled. Filling listen list."); \
- for (count = 0; count < boundPortCount; count++) \
- { \
- struct kevent ke; \
- log(DEBUG,"kqueue: Add listening socket to events, kq=%d socket=%d",lkq,openSockfd[count]); \
- EV_SET(&ke, openSockfd[count], EVFILT_READ, EV_ADD, 0, MaxConn, NULL); \
- int i = kevent(lkq, &ke, 1, 0, 0, NULL); \
- if (i == -1) \
- { \
- log(DEFAULT,"main: add listen ports to kqueue failed!"); \
- printf("ERROR: could not initialise listening sockets in kqueue. Shutting down.\n"); \
- Exit(ERROR); \
- } \
- } \
- for (int t = 0; t != SERVERportCount; t++) \
- { \
- struct kevent ke; \
- if (me[t]) \
- { \
- log(DEBUG,"kqueue: Add listening SERVER socket to events, kq=%d socket=%d",skq,me[t]->fd); \
- EV_SET(&ke, me[t]->fd, EVFILT_READ, EV_ADD, 0, MaxConn, NULL); \
- int i = kevent(skq, &ke, 1, 0, 0, NULL); \
- if (i == -1) \
- { \
- log(DEFAULT,"main: add server listen ports to kqueue failed!"); \
- printf("ERROR: could not initialise listening server sockets in kqueue. Shutting down.\n"); \
- Exit(ERROR); \
- } \
- } \
- }
-
-#ifdef USE_EPOLL
-#define engine_server_fill epoll_server_fill
-#endif
-#ifdef USE_KQUEUE
-#define engine_server_fill kqueue_server_fill
-#endif
-#ifdef USE_SELECT
-#define engine_server_fill select_server_fill
-#endif
-
-
-// what is this engine called?
+#ifndef __SOCKETENGINE__
+#define __SOCKETENGINE__
+
+#include <vector>
+#include <string>
+#include <map>
+#include "inspircd_config.h"
+#include "base.h"
+
+/** Types of event an EventHandler may receive.
+ * EVENT_READ is a readable file descriptor,
+ * and EVENT_WRITE is a writeable file descriptor.
+ * EVENT_ERROR can always occur, and indicates
+ * a write error or read error on the socket,
+ * e.g. EOF condition or broken pipe.
+ */
+enum EventType
+{
+ /** Read event */
+ EVENT_READ = 0,
+ /** Write event */
+ EVENT_WRITE = 1,
+ /** Error event */
+ EVENT_ERROR = 2
+};
+
+/**
+ * Event mask for SocketEngine events
+ */
+enum EventMask
+{
+ /** Do not test this socket for readability
+ */
+ FD_WANT_NO_READ = 0x1,
+ /** Give a read event at all times when reads will not block.
+ */
+ FD_WANT_POLL_READ = 0x2,
+ /** Give a read event when there is new data to read.
+ *
+ * An event MUST be sent if there is new data to be read, and the most
+ * recent read/recv() on this FD returned EAGAIN. An event MAY be sent
+ * at any time there is data to be read on the socket.
+ */
+ FD_WANT_FAST_READ = 0x4,
+ /** Give an optional read event when reads begin to unblock
+ *
+ * This state is useful if you want to leave data in the OS receive
+ * queue but not get continuous event notifications about it, because
+ * it may not require a system call to transition from FD_WANT_FAST_READ
+ */
+ FD_WANT_EDGE_READ = 0x8,
+
+ /** Mask for all read events */
+ FD_WANT_READ_MASK = 0x0F,
+
+ /** Do not test this socket for writeability
+ */
+ FD_WANT_NO_WRITE = 0x10,
+ /** Give a write event at all times when writes will not block.
+ *
+ * You probably shouldn't use this state; if it's likely that the write
+ * will not block, try it first, then use FD_WANT_FAST_WRITE if it
+ * fails. If it's likely to block (or you are using polling-style reads)
+ * then use FD_WANT_SINGLE_WRITE.
+ */
+ FD_WANT_POLL_WRITE = 0x20,
+ /** Give a write event when writes don't block any more
+ *
+ * An event MUST be sent if writes will not block, and the most recent
+ * write/send() on this FD returned EAGAIN, or connect() returned
+ * EINPROGRESS. An event MAY be sent at any time that writes will not
+ * block.
+ *
+ * Before calling HandleEvent, a socket engine MAY change the state of
+ * the FD back to FD_WANT_EDGE_WRITE if it is simpler (for example, if a
+ * one-shot notification was registered). If further writes are needed,
+ * it is the responsibility of the event handler to change the state to
+ * one that will generate the required notifications
+ */
+ FD_WANT_FAST_WRITE = 0x40,
+ /** Give an optional write event on edge-triggered write unblock.
+ *
+ * This state is useful to avoid system calls when moving to/from
+ * FD_WANT_FAST_WRITE when writing data to a mostly-unblocked socket.
+ */
+ FD_WANT_EDGE_WRITE = 0x80,
+ /** Request a one-shot poll-style write notification. The socket will
+ * return to the FD_WANT_NO_WRITE state before HandleEvent is called.
+ */
+ FD_WANT_SINGLE_WRITE = 0x100,
+
+ /** Mask for all write events */
+ FD_WANT_WRITE_MASK = 0x1F0,
+
+ /** Add a trial read. During the next DispatchEvents invocation, this
+ * will call HandleEvent with EVENT_READ unless reads are known to be
+ * blocking.
+ */
+ FD_ADD_TRIAL_READ = 0x1000,
+ /** Assert that reads are known to block. This cancels FD_ADD_TRIAL_READ.
+ * Reset by SE before running EVENT_READ
+ */
+ FD_READ_WILL_BLOCK = 0x2000,
+
+ /** Add a trial write. During the next DispatchEvents invocation, this
+ * will call HandleEvent with EVENT_WRITE unless writes are known to be
+ * blocking.
+ *
+ * This could be used to group several writes together into a single
+ * send() syscall, or to ensure that writes are blocking when attempting
+ * to use FD_WANT_FAST_WRITE.
+ */
+ FD_ADD_TRIAL_WRITE = 0x4000,
+ /** Assert that writes are known to block. This cancels FD_ADD_TRIAL_WRITE.
+ * Reset by SE before running EVENT_WRITE
+ */
+ FD_WRITE_WILL_BLOCK = 0x8000,
+
+ /** Mask for trial read/trial write */
+ FD_TRIAL_NOTE_MASK = 0x5000
+};
+
+class InspIRCd;
+class Module;
+
+/** This class is a basic I/O handler class.
+ * Any object which wishes to receive basic I/O events
+ * from the socketengine must derive from this class and
+ * implement the HandleEvent() method. The derived class
+ * must then be added to SocketEngine using the method
+ * SocketEngine::AddFd(), after which point the derived
+ * class will receive events to its HandleEvent() method.
+ * The derived class should also implement one of Readable()
+ * and Writeable(). In the current implementation, only
+ * Readable() is used. If this returns true, the socketengine
+ * inserts a readable socket. If it is false, the socketengine
+ * inserts a writeable socket. The derived class should never
+ * change the value this function returns without first
+ * deleting the socket from the socket engine. The only
+ * requirement beyond this for an event handler is that it
+ * must have a file descriptor. What this file descriptor
+ * is actually attached to is completely up to you.
+ */
+class CoreExport EventHandler : public Extensible
+{
+ private:
+ /** Private state maintained by socket engine */
+ int event_mask;
+ protected:
+ /** File descriptor.
+ * All events which can be handled must have a file descriptor. This
+ * allows you to add events for sockets, fifo's, pipes, and various
+ * other forms of IPC. Do not change this while the object is
+ * registered with the SocketEngine
+ */
+ int fd;
+ public:
+ /** Get the current file descriptor
+ * @return The file descriptor of this handler
+ */
+ inline int GetFd() const { return fd; }
+
+ inline int GetEventMask() const { return event_mask; }
+
+ /** Set a new file desciptor
+ * @param FD The new file descriptor. Do not call this method without
+ * first deleting the object from the SocketEngine if you have
+ * added it to a SocketEngine instance.
+ */
+ void SetFd(int FD);
+
+ /** Constructor
+ */
+ EventHandler();
+
+ /** Destructor
+ */
+ virtual ~EventHandler() {}
+
+ /** Process an I/O event.
+ * You MUST implement this function in your derived
+ * class, and it will be called whenever read or write
+ * events are received.
+ * @param et either one of EVENT_READ for read events,
+ * and EVENT_WRITE for write events.
+ */
+ virtual void HandleEvent(EventType et, int errornum = 0) = 0;
+
+ friend class SocketEngine;
+};
+
+/** Provides basic file-descriptor-based I/O support.
+ * The actual socketengine class presents the
+ * same interface on all operating systems, but
+ * its private members and internal behaviour
+ * should be treated as blackboxed, and vary
+ * from system to system and upon the config
+ * settings chosen by the server admin. The current
+ * version supports select, epoll and kqueue.
+ * The configure script will enable a socket engine
+ * based upon what OS is detected, and will derive
+ * a class from SocketEngine based upon what it finds.
+ * The derived classes file will also implement a
+ * classfactory, SocketEngineFactory, which will
+ * create a derived instance of SocketEngine using
+ * polymorphism so that the core and modules do not
+ * have to be aware of which SocketEngine derived
+ * class they are using.
+ */
+class CoreExport SocketEngine
+{
+ protected:
+ /** Current number of descriptors in the engine
+ */
+ int CurrentSetSize;
+ /** Reference table, contains all current handlers
+ */
+ EventHandler** ref;
+ /** List of handlers that want a trial read/write
+ */
+ std::set<int> trials;
+
+ int MAX_DESCRIPTORS;
+
+ size_t indata;
+ size_t outdata;
+ time_t lastempty;
+
+ void UpdateStats(size_t len_in, size_t len_out);
+
+ virtual void OnSetEvent(EventHandler* eh, int old_mask, int new_mask) = 0;
+ void SetEventMask(EventHandler* eh, int value);
+public:
+
+ double TotalEvents;
+ double ReadEvents;
+ double WriteEvents;
+ double ErrorEvents;
+
+ /** Constructor.
+ * The constructor transparently initializes
+ * the socket engine which the ircd is using.
+ * Please note that if there is a catastrophic
+ * failure (for example, you try and enable
+ * epoll on a 2.4 linux kernel) then this
+ * function may bail back to the shell.
+ */
+ SocketEngine();
+
+ /** Destructor.
+ * The destructor transparently tidies up
+ * any resources used by the socket engine.
+ */
+ virtual ~SocketEngine();
+
+ /** Add an EventHandler object to the engine. Use AddFd to add a file
+ * descriptor to the engine and have the socket engine monitor it. You
+ * must provide an object derived from EventHandler which implements
+ * HandleEvent().
+ * @param eh An event handling object to add
+ * @param event_mask The initial event mask for the object
+ */
+ virtual bool AddFd(EventHandler* eh, int event_mask) = 0;
+
+ /** If you call this function and pass it an
+ * event handler, that event handler will
+ * receive the next available write event,
+ * even if the socket is a readable socket only.
+ * Developers should avoid constantly keeping
+ * an eventhandler in the writeable state,
+ * as this will consume large amounts of
+ * CPU time.
+ * @param eh The event handler to change
+ * @param event_mask The changes to make to the wait state
+ */
+ void ChangeEventMask(EventHandler* eh, int event_mask);
+
+ /** Returns the highest file descriptor you may store in the socket engine
+ * @return The maximum fd value
+ */
+ inline int GetMaxFds() const { return MAX_DESCRIPTORS; }
+
+ /** Returns the number of file descriptors being queried
+ * @return The set size
+ */
+ inline int GetUsedFds() const { return CurrentSetSize; }
+
+ /** Delete an event handler from the engine.
+ * This function call deletes an EventHandler
+ * from the engine, returning true if it succeeded
+ * and false if it failed. This does not free the
+ * EventHandler pointer using delete, if this is
+ * required you must do this yourself.
+ * Note on forcing deletes. DO NOT DO THIS! This is
+ * extremely dangerous and will most likely render the
+ * socketengine dead. This was added only for handling
+ * very rare cases where broken 3rd party libs destroys
+ * the OS socket beyond our control. If you can't explain
+ * in minute details why forcing is absolutely necessary
+ * then you don't need it. That was a NO!
+ * @param eh The event handler object to remove
+ * @param force *DANGEROUS* See method description!
+ * @return True if the event handler was removed
+ */
+ virtual bool DelFd(EventHandler* eh, bool force = false) = 0;
+
+ /** Returns true if a file descriptor exists in
+ * the socket engine's list.
+ * @param fd The event handler to look for
+ * @return True if this fd has an event handler
+ */
+ virtual bool HasFd(int fd);
+
+ /** Returns the EventHandler attached to a specific fd.
+ * If the fd isnt in the socketengine, returns NULL.
+ * @param fd The event handler to look for
+ * @return A pointer to the event handler, or NULL
+ */
+ virtual EventHandler* GetRef(int fd);
+
+ /** Waits for events and dispatches them to handlers. Please note that
+ * this doesn't wait long, only a couple of milliseconds. It returns the
+ * number of events which occurred during this call. This method will
+ * dispatch events to their handlers by calling their
+ * EventHandler::HandleEvent() methods with the necessary EventType
+ * value.
+ * @return The number of events which have occured.
+ */
+ virtual int DispatchEvents() = 0;
+
+ /** Dispatch trial reads and writes. This causes the actual socket I/O
+ * to happen when writes have been pre-buffered.
+ */
+ virtual void DispatchTrialWrites();
+
+ /** Returns the socket engines name. This returns the name of the
+ * engine for use in /VERSION responses.
+ * @return The socket engine name
+ */
+ virtual std::string GetName() = 0;
+
+ /** Returns true if the file descriptors in the given event handler are
+ * within sensible ranges which can be handled by the socket engine.
+ */
+ virtual bool BoundsCheckFd(EventHandler* eh);
+
+ /** Abstraction for BSD sockets accept(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Accept(EventHandler* fd, sockaddr *addr, socklen_t *addrlen);
+
+ /** Abstraction for BSD sockets close(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Close(EventHandler* fd);
+
+ /** Abstraction for BSD sockets close(2).
+ * This function should emulate its namesake system call exactly.
+ * This function should emulate its namesake system call exactly.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Close(int fd);
+
+ /** Abstraction for BSD sockets send(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Send(EventHandler* fd, const void *buf, size_t len, int flags);
+
+ /** Abstraction for BSD sockets recv(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Recv(EventHandler* fd, void *buf, size_t len, int flags);
+
+ /** Abstraction for BSD sockets recvfrom(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int RecvFrom(EventHandler* fd, void *buf, size_t len, int flags, sockaddr *from, socklen_t *fromlen);
+
+ /** Abstraction for BSD sockets sendto(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int SendTo(EventHandler* fd, const void *buf, size_t len, int flags, const sockaddr *to, socklen_t tolen);
+
+ /** Abstraction for BSD sockets connect(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Connect(EventHandler* fd, const sockaddr *serv_addr, socklen_t addrlen);
+
+ /** Make a file descriptor blocking.
+ * @param fd a file descriptor to set to blocking mode
+ * @return 0 on success, -1 on failure, errno is set appropriately.
+ */
+ virtual int Blocking(int fd);
+
+ /** Make a file descriptor nonblocking.
+ * @param fd A file descriptor to set to nonblocking mode
+ * @return 0 on success, -1 on failure, errno is set appropriately.
+ */
+ virtual int NonBlocking(int fd);
+
+ /** Abstraction for BSD sockets shutdown(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Shutdown(EventHandler* fd, int how);
+
+ /** Abstraction for BSD sockets shutdown(2).
+ * This function should emulate its namesake system call exactly.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Shutdown(int fd, int how);
+
+ /** Abstraction for BSD sockets bind(2).
+ * This function should emulate its namesake system call exactly.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Bind(int fd, const sockaddr *my_addr, socklen_t addrlen);
+
+ /** Abstraction for BSD sockets listen(2).
+ * This function should emulate its namesake system call exactly.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int Listen(int sockfd, int backlog);
+
+ /** Abstraction for BSD sockets getsockname(2).
+ * This function should emulate its namesake system call exactly.
+ * @param fd This version of the call takes an EventHandler instead of a bare file descriptor.
+ * @return This method should return exactly the same values as the system call it emulates.
+ */
+ virtual int GetSockName(EventHandler* fd, sockaddr *name, socklen_t* namelen);
+
+ /** This function is called immediately after fork().
+ * Some socket engines (notably kqueue) cannot have their
+ * handles inherited by forked processes. This method
+ * allows for the socket engine to re-create its handle
+ * after the daemon forks as the socket engine is created
+ * long BEFORE the daemon forks.
+ * @return void, but it is acceptable for this function to bail back to
+ * the shell or operating system on fatal error.
+ */
+ virtual void RecoverFromFork();
+
+ /** Get data transfer statistics, kilobits per second in and out and total.
+ */
+ void GetStats(float &kbitpersec_in, float &kbitpersec_out, float &kbitpersec_total);
+};
+
+SocketEngine* CreateSocketEngine();
-#ifdef USE_KQUEUE
-#define engine_name "kqueue"
-#endif
-#ifdef USE_SELECT
-#define engine_name "select"
-#endif
-#ifdef USE_EPOLL
-#define engine_name "epoll"
#endif