* | Inspire Internet Relay Chat Daemon |
* +------------------------------------+
*
- * InspIRCd is copyright (C) 2002-2006 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.
*
* ---------------------------------------------------
-*/
+ */
#ifndef __SOCKETENGINE__
#define __SOCKETENGINE__
#include <string>
#include <map>
#include "inspircd_config.h"
-#include "globals.h"
-#include "inspircd.h"
-#ifdef USE_EPOLL
-#include <sys/epoll.h>
-#define EP_DELAY 5
-#endif
-#ifdef USE_KQUEUE
-#include <sys/types.h>
-#include <sys/event.h>
-#include <sys/time.h>
-#endif
+#include "base.h"
-/**
- * Each of these values represents a socket
- * type in our reference table (the reference
- * table itself is only accessible to
- * socketengine.cpp)
+/** 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.
*/
-const char X_EMPTY_SLOT = 0;
-const char X_LISTEN = 1;
-const char X_ESTAB_CLIENT = 2;
-const char X_ESTAB_MODULE = 3;
-const char X_ESTAB_DNS = 4;
+enum EventType
+{
+ /** Read event */
+ EVENT_READ = 0,
+ /** Write event */
+ EVENT_WRITE = 1,
+ /** Error event */
+ EVENT_ERROR = 2
+};
/**
- * To indicate that a socket is readable, we
- * mask its top bit with this X_READBIT value.
- * The socket engine can handle two types of
- * socket, readable and writeable (error sockets
- * are dealt with when read() and write() return
- * negative or zero values).
+ * Event mask for SocketEngine events
*/
-const char X_READBIT = 0x80;
+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
* 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 SocketEngine : public Extensible
+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 EngineHandle; /* Handle to the socket engine if needed */
- int CurrentSetSize; /* Current number of descriptors in the engine */
-#ifdef USE_SELECT
- std::map<int,int> fds; /* List of file descriptors being monitored */
- fd_set wfdset, rfdset; /* Readable and writeable sets for select() */
-#endif
-#ifdef USE_KQUEUE
- struct kevent ke_list[MAX_DESCRIPTORS]; /* Up to 64k sockets for kqueue */
- struct timespec ts; /* kqueue delay value */
-#endif
-#ifdef USE_EPOLL
- struct epoll_event events[MAX_DESCRIPTORS]; /* Up to 64k sockets for epoll */
-#endif
+ 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:
- /** Constructor
+ 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
*/
SocketEngine();
- /** Destructor
+ /** Destructor.
* The destructor transparently tidies up
* any resources used by the socket engine.
*/
- ~SocketEngine();
+ virtual ~SocketEngine();
- /** Add a file descriptor to the engine
- * Use AddFd to add a file descriptor to the
- * engine and have the socket engine monitor
- * it. You must provide a type (see the consts
- * in socketengine.h) and a boolean flag to
- * indicate wether to watch this fd for read
- * or write events (there is currently no
- * need for support of both).
+ /** 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
*/
- bool AddFd(int fd, bool readable, char type);
+ virtual bool AddFd(EventHandler* eh, int event_mask) = 0;
- /** Returns the type value for this file descriptor
- * This function masks off the X_READBIT value
- * so that the type of the socket can be obtained.
- * The core uses this to decide where to dispatch
- * the event to. Please note that some engines
- * such as select() have an upper limit of 1024
- * descriptors which may be active at any one time,
- * where others such as kqueue have no practical
- * limits at all.
+ /** 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
*/
- char GetType(int fd);
+ void ChangeEventMask(EventHandler* eh, int event_mask);
- /** Returns the maximum number of file descriptors
- * you may store in the socket engine at any one time.
+ /** Returns the highest file descriptor you may store in the socket engine
+ * @return The maximum fd value
*/
- int GetMaxFds();
+ inline int GetMaxFds() const { return MAX_DESCRIPTORS; }
- /** Returns the number of file descriptor slots
- * which are available for storing fds.
+ /** Returns the number of file descriptors being queried
+ * @return The set size
*/
- int GetRemainingFds();
+ inline int GetUsedFds() const { return CurrentSetSize; }
- /** Delete a file descriptor from the engine
- * This function call deletes a file descriptor
+ /** 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.
+ * 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.
*/
- bool DelFd(int fd);
+ virtual int Close(int fd);
- /** Returns true if a socket exists in the socket
- * engine's list.
+ /** 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.
*/
- bool HasFd(int fd);
+ virtual int Send(EventHandler* fd, const void *buf, size_t len, int flags);
- /** Waits for an event.
- * Please note that this doesnt wait long, only
- * a couple of milliseconds. It returns a list
- * of active file descriptors in the vector
- * fdlist which the core may then act upon.
+ /** 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.
*/
- int Wait(int* fdlist);
+ virtual int Recv(EventHandler* fd, void *buf, size_t len, int flags);
- /** Returns the socket engines name
- * This returns the name of the engine for use
- * in /VERSION responses.
+ /** 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.
*/
- std::string GetName();
+ 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();
+
#endif
+