source: trunk/gsdl/packages/yaz/server/eventl.c@ 1343

/*
 * Copyright (c) 1995-1999, Index Data
 * See the file LICENSE for details.
 * Sebastian Hammer, Adam Dickmeiss
 *
 * $Log$
 * Revision 1.1  2000/08/03 03:11:40  johnmcp
 * Added the YAZ toolkit source to the packages directory (for z39.50 stuff)
 *
 * Revision 1.29  1999/11/30 13:47:12  adam
 * Improved installation. Moved header files to include/yaz.
 *
 * Revision 1.28  1999/08/27 09:40:32  adam
 * Renamed logf function to yaz_log. Removed VC++ project files.
 *
 * Revision 1.27  1999/02/02 13:57:34  adam
 * Uses preprocessor define WIN32 instead of WINDOWS to build code
 * for Microsoft WIN32.
 *
 * Revision 1.26  1998/02/11 11:53:35  adam
 * Changed code so that it compiles as C++.
 *
 * Revision 1.25  1998/01/29 13:30:23  adam
 * Better event handle system for NT/Unix.
 *
 * Revision 1.24  1997/09/04 14:19:13  adam
 * Added credits.
 *
 * Revision 1.23  1997/09/01 08:52:59  adam
 * New windows NT/95 port using MSV5.0. The test server 'ztest' was
 * moved a separate directory. MSV5.0 project server.dsp created.
 * As an option, the server can now operate as an NT service.
 *
 * Revision 1.22  1996/07/06 19:58:35  quinn
 * System headerfiles gathered in yconfig
 *
 * Revision 1.21  1996/02/21  12:55:51  quinn
 * small
 *
 * Revision 1.20  1996/02/21  12:52:55  quinn
 * Test
 *
 * Revision 1.19  1995/12/05  11:17:30  quinn
 * Moved some paranthesises around. Sigh.
 *
 * Revision 1.18  1995/11/13  09:27:41  quinn
 * Fiddling with the variant stuff.
 *
 * Revision 1.17  1995/11/07  12:37:44  quinn
 * Added support for forcing TIMEOUT event.
 *
 * Revision 1.16  1995/11/01  13:54:56  quinn
 * Minor adjustments
 *
 * Revision 1.15  1995/09/15  14:44:15  quinn
 * *** empty log message ***
 *
 * Revision 1.14  1995/08/29  14:44:50  quinn
 * Reset timeouts.
 *
 * Revision 1.13  1995/08/29  11:17:56  quinn
 * Added code to receive close
 *
 * Revision 1.12  1995/08/29  10:41:18  quinn
 * Small.
 *
 * Revision 1.11  1995/06/19  12:39:09  quinn
 * Fixed bug in timeout code. Added BER dumper.
 *
 * Revision 1.10  1995/06/16  10:31:33  quinn
 * Added session timeout.
 *
 * Revision 1.9  1995/06/05  10:53:31  quinn
 * Added a better SCAN.
 *
 * Revision 1.8  1995/05/16  08:51:01  quinn
 * License, documentation, and memory fixes
 *
 * Revision 1.7  1995/03/27  15:02:01  quinn
 * Added some includes for better portability
 *
 * Revision 1.6  1995/03/27  08:34:21  quinn
 * Added dynamic server functionality.
 * Released bindings to session.c (is now redundant)
 *
 * Revision 1.5  1995/03/15  08:37:41  quinn
 * Now we're pretty much set for nonblocking I/O.
 *
 * Revision 1.4  1995/03/14  16:59:48  quinn
 * Bug-fixes
 *
 * Revision 1.3  1995/03/14  11:30:14  quinn
 * Works better now.
 *
 * Revision 1.2  1995/03/14  10:27:59  quinn
 * More work on demo server.
 *
 * Revision 1.1  1995/03/10  18:22:44  quinn
 * The rudiments of an asynchronous server.
 *
 */

#include <stdio.h>
#include <assert.h>
#ifdef WIN32
#include <winsock.h>
#else
#include <unistd.h>
#endif
#include <stdlib.h>
#include <errno.h>
#include <string.h>

#include <yaz/yconfig.h>
#include <yaz/log.h>
#include <yaz/comstack.h>
#include <yaz/xmalloc.h>
#include "eventl.h"
#include "session.h"
#include <yaz/statserv.h>

IOCHAN iochan_create(int fd, IOC_CALLBACK cb, int flags)
{
    IOCHAN new_iochan;

    if (!(new_iochan = (IOCHAN)xmalloc(sizeof(*new_iochan))))
        return 0;
    new_iochan->destroyed = 0;
    new_iochan->fd = fd;
    new_iochan->flags = flags;
    new_iochan->fun = cb;
    new_iochan->force_event = 0;
    new_iochan->last_event = new_iochan->max_idle = 0;
    new_iochan->next = NULL;
    return new_iochan;
}

int event_loop(IOCHAN *iochans)
{
    do /* loop as long as there are active associations to process */
    {
        IOCHAN p, nextp;
    fd_set in, out, except;
    int res, max;
    static struct timeval nullto = {0, 0}, to;
    struct timeval *timeout;

    FD_ZERO(&in);
    FD_ZERO(&out);
    FD_ZERO(&except);
    timeout = &to; /* hang on select */
    to.tv_sec = 5*60;
    to.tv_usec = 0;
    max = 0;
        for (p = *iochans; p; p = p->next)
        {
        if (p->force_event)
        timeout = &nullto;        /* polling select */
        if (p->flags & EVENT_INPUT)
        FD_SET(p->fd, &in);
        if (p->flags & EVENT_OUTPUT)
            FD_SET(p->fd, &out);
        if (p->flags & EVENT_EXCEPT)
            FD_SET(p->fd, &except);
        if (p->fd > max)
            max = p->fd;
    }
    if ((res = select(max + 1, &in, &out, &except, timeout)) < 0)
    {
        if (errno == EINTR)
            continue;
            else
            {
                /* Destroy the first member in the chain, and try again */
                association *assoc = (association *)iochan_getdata(*iochans);
                COMSTACK conn = assoc->client_link;

                cs_close(conn);
            destroy_association(assoc);
            iochan_destroy(*iochans);
                yaz_log(LOG_DEBUG, "error select, destroying iochan %p",
            *iochans);
            }
    }
        for (p = *iochans; p; p = p->next)
        {
        int force_event = p->force_event;
        time_t now = time(0);

        p->force_event = 0;
        if (!p->destroyed && (FD_ISSET(p->fd, &in) ||
        force_event == EVENT_INPUT))
        {
            p->last_event = now;
        (*p->fun)(p, EVENT_INPUT);
        }
        if (!p->destroyed && (FD_ISSET(p->fd, &out) ||
            force_event == EVENT_OUTPUT))
        {
        p->last_event = now;
            (*p->fun)(p, EVENT_OUTPUT);
        }
        if (!p->destroyed && (FD_ISSET(p->fd, &except) ||
            force_event == EVENT_EXCEPT))
        {
        p->last_event = now;
            (*p->fun)(p, EVENT_EXCEPT);
        }
        if (!p->destroyed && ((p->max_idle && now - p->last_event >
            p->max_idle) || force_event == EVENT_TIMEOUT))
        {
            p->last_event = now;
            (*p->fun)(p, EVENT_TIMEOUT);
        }
    }
    for (p = *iochans; p; p = nextp)
    {
        nextp = p->next;

        if (p->destroyed)
        {
        IOCHAN tmp = p, pr;

                /* We need to inform the threadlist that this channel has been destroyed */
                statserv_remove(p);

            /* Now reset the pointers */
                if (p == *iochans)
            *iochans = p->next;
        else
        {
            for (pr = *iochans; pr; pr = pr->next)
                if (pr->next == p)
                        break;
            assert(pr); /* grave error if it weren't there */
            pr->next = p->next;
        }
        if (nextp == p)
            nextp = p->next;
        xfree(tmp);
        }
    }
    }
    while (*iochans);
    return 0;
}