Edit

kc3-lang/libevent/iocp-internal.h

Branch :

  • Show log

    Commit

  • Author : Nick Mathewson
    Date : 2011-10-24 13:18:09
    Hash : 3c824bd3
    Message : Update copyright dates to 2011.

  • iocp-internal.h
  • /*
     * Copyright (c) 2009-2011 Niels Provos and Nick Mathewson
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. The name of the author may not be used to endorse or promote products
     *    derived from this software without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     */
    
    #ifndef _EVENT_IOCP_INTERNAL_H
    #define _EVENT_IOCP_INTERNAL_H
    
    #ifdef __cplusplus
    extern "C" {
    #endif
    
    struct event_overlapped;
    struct event_iocp_port;
    struct evbuffer;
    typedef void (*iocp_callback)(struct event_overlapped *, ev_uintptr_t, ev_ssize_t, int success);
    
    /* This whole file is actually win32 only. We wrap the structures in a win32
     * ifdef so that we can test-compile code that uses these interfaces on
     * non-win32 platforms. */
    #ifdef WIN32
    
    /**
       Internal use only.  Wraps an OVERLAPPED that we're using for libevent
       functionality.  Whenever an event_iocp_port gets an event for a given
       OVERLAPPED*, it upcasts the pointer to an event_overlapped, and calls the
       iocp_callback function with the event_overlapped, the iocp key, and the
       number of bytes transferred as arguments.
     */
    struct event_overlapped {
    	OVERLAPPED overlapped;
    	iocp_callback cb;
    };
    
    /* Mingw's headers don't define LPFN_ACCEPTEX. */
    
    typedef BOOL (WINAPI *AcceptExPtr)(SOCKET, SOCKET, PVOID, DWORD, DWORD, DWORD, LPDWORD, LPOVERLAPPED);
    typedef BOOL (WINAPI *ConnectExPtr)(SOCKET, const struct sockaddr *, int, PVOID, DWORD, LPDWORD, LPOVERLAPPED);
    typedef void (WINAPI *GetAcceptExSockaddrsPtr)(PVOID, DWORD, DWORD, DWORD, LPSOCKADDR *, LPINT, LPSOCKADDR *, LPINT);
    
    /** Internal use only. Holds pointers to functions that only some versions of
        Windows provide.
     */
    struct win32_extension_fns {
    	AcceptExPtr AcceptEx;
    	ConnectExPtr ConnectEx;
    	GetAcceptExSockaddrsPtr GetAcceptExSockaddrs;
    };
    
    /**
        Internal use only. Stores a Windows IO Completion port, along with
        related data.
     */
    struct event_iocp_port {
    	/** The port itself */
    	HANDLE port;
    	/* A lock to cover internal structures. */
    	CRITICAL_SECTION lock;
    	/** Number of threads ever open on the port. */
    	short n_threads;
    	/** True iff we're shutting down all the threads on this port */
    	short shutdown;
    	/** How often the threads on this port check for shutdown and other
    	 * conditions */
    	long ms;
    	/* The threads that are waiting for events. */
    	HANDLE *threads;
    	/** Number of threads currently open on this port. */
    	short n_live_threads;
    	/** A semaphore to signal when we are done shutting down. */
    	HANDLE *shutdownSemaphore;
    };
    
    const struct win32_extension_fns *event_get_win32_extension_fns(void);
    #else
    /* Dummy definition so we can test-compile more things on unix. */
    struct event_overlapped {
    	iocp_callback cb;
    };
    #endif
    
    /** Initialize the fields in an event_overlapped.
    
        @param overlapped The struct event_overlapped to initialize
        @param cb The callback that should be invoked once the IO operation has
    	finished.
     */
    void event_overlapped_init(struct event_overlapped *, iocp_callback cb);
    
    /** Allocate and return a new evbuffer that supports overlapped IO on a given
        socket.  The socket must be associated with an IO completion port using
        event_iocp_port_associate.
    */
    struct evbuffer *evbuffer_overlapped_new(evutil_socket_t fd);
    
    /** XXXX Document (nickm) */
    evutil_socket_t _evbuffer_overlapped_get_fd(struct evbuffer *buf);
    
    void _evbuffer_overlapped_set_fd(struct evbuffer *buf, evutil_socket_t fd);
    
    /** Start reading data onto the end of an overlapped evbuffer.
    
        An evbuffer can only have one read pending at a time.  While the read
        is in progress, no other data may be added to the end of the buffer.
        The buffer must be created with event_overlapped_init().
        evbuffer_commit_read() must be called in the completion callback.
    
        @param buf The buffer to read onto
        @param n The number of bytes to try to read.
        @param ol Overlapped object with associated completion callback.
        @return 0 on success, -1 on error.
     */
    int evbuffer_launch_read(struct evbuffer *buf, size_t n, struct event_overlapped *ol);
    
    /** Start writing data from the start of an evbuffer.
    
        An evbuffer can only have one write pending at a time.  While the write is
        in progress, no other data may be removed from the front of the buffer.
        The buffer must be created with event_overlapped_init().
        evbuffer_commit_write() must be called in the completion callback.
    
        @param buf The buffer to read onto
        @param n The number of bytes to try to read.
        @param ol Overlapped object with associated completion callback.
        @return 0 on success, -1 on error.
     */
    int evbuffer_launch_write(struct evbuffer *buf, ev_ssize_t n, struct event_overlapped *ol);
    
    /** XXX document */
    void evbuffer_commit_read(struct evbuffer *, ev_ssize_t);
    void evbuffer_commit_write(struct evbuffer *, ev_ssize_t);
    
    /** Create an IOCP, and launch its worker threads.  Internal use only.
    
        This interface is unstable, and will change.
     */
    struct event_iocp_port *event_iocp_port_launch(int n_cpus);
    
    /** Associate a file descriptor with an iocp, such that overlapped IO on the
        fd will happen on one of the iocp's worker threads.
    */
    int event_iocp_port_associate(struct event_iocp_port *port, evutil_socket_t fd,
        ev_uintptr_t key);
    
    /** Tell all threads serving an iocp to stop.  Wait for up to waitMsec for all
        the threads to finish whatever they're doing.  If waitMsec is -1, wait
        as long as required.  If all the threads are done, free the port and return
        0. Otherwise, return -1.  If you get a -1 return value, it is safe to call
        this function again.
    */
    int event_iocp_shutdown(struct event_iocp_port *port, long waitMsec);
    
    /* FIXME document. */
    int event_iocp_activate_overlapped(struct event_iocp_port *port,
        struct event_overlapped *o,
        ev_uintptr_t key, ev_uint32_t n_bytes);
    
    struct event_base;
    /* FIXME document. */
    struct event_iocp_port *event_base_get_iocp(struct event_base *base);
    
    /* FIXME document. */
    int event_base_start_iocp(struct event_base *base, int n_cpus);
    void event_base_stop_iocp(struct event_base *base);
    
    /* FIXME document. */
    struct bufferevent *bufferevent_async_new(struct event_base *base,
        evutil_socket_t fd, int options);
    
    /* FIXME document. */
    void bufferevent_async_set_connected(struct bufferevent *bev);
    int bufferevent_async_can_connect(struct bufferevent *bev);
    int bufferevent_async_connect(struct bufferevent *bev, evutil_socket_t fd,
    	const struct sockaddr *sa, int socklen);
    
    #ifdef __cplusplus
    }
    #endif
    
    #endif