htevtlst.c

www工具包. 这是W3C官方支持的www支撑库. 其中提供通用目的的客户端的WebAPI: complete HTTP/1.1 (with caching, pipelining, PUT, POS

/*				    				     HTEvtLst.c
**	EVENT MANAGER
**
**	(c) COPYRIGHT MIT 1995.
**	Please first read the full copyright statement in the file COPYRIGH.
**	@(#) $Id: HTEvtLst.c,v 2.45 2000/08/02 10:38:07 kahan Exp $
**
**	Updated HTEvent module 
**	This new module combines the functions of the old HTEvent module and 
**	the HTThread module. We retain the old HTThread module, but it
**	consists of calls to the HTEvent interfaces
**
** Authors:
**	HFN	Henrik Frystyk <[e-mail]>
**	CLB    	Charlie Brooks <[e-mail]>
** Bugs
**
*/

/*   WSAAsyncSelect and windows app stuff need the following definitions:
 *   WWW_WIN_ASYNC - enable WSAAsyncSelect instead of select
 *   _WIN23 - win32 libararies - may be window or console app
 *   _WINSOCKAPI_ - using WINSOCK.DLL - not necessarily the async routines.
 *   _CONSOLE - the console app for NT
 *
 * first pass: EGP - 10/26/95
 */

/* Implementation dependent include files */
#include "wwwsys.h"
#include "WWWUtil.h"
#include "WWWCore.h"
#include "HTReqMan.h"
#include "HTTimer.h"
#include "HTEvent.h"
#include "HTEvtLst.h"					 /* Implemented here */

/* Type definitions and global variables etc. local to this module */
#define MILLI_PER_SECOND	1000
#define HASH(s)			((s) % HT_M_HASH_SIZE) 

#define EVENTS_TO_EXECUTE	10 /* how many to execute in one select loop */

#define HT_FS_BYTES(a)		((((a)/16)+1) * 4)

typedef struct {
    SOCKET 	s ;	 		/* our socket */
    HTEvent * 	events[HTEvent_TYPES];	/* event parameters for read, write, oob */
    HTTimer *	timeouts[HTEvent_TYPES];
} SockEvents;

typedef struct {
    HTEvent *	event;
    SOCKET	s;
    HTEventType	type;
    HTPriority	skipped;
} EventOrder;

typedef enum {
    SockEvents_mayCreate,
    SockEvents_find
} SockEvents_action;

PRIVATE HTList * HashTable [HT_M_HASH_SIZE]; 
PRIVATE HTList * EventOrderList = NULL;
PRIVATE int HTEndLoop = 0;		       /* If !0 then exit event loop */
PRIVATE BOOL HTInLoop = NO;

#ifdef WWW_WIN_ASYNC
#define TIMEOUT	1 /* WM_TIMER id */
PRIVATE HWND HTSocketWin;
PRIVATE ATOM HTclass;
PRIVATE HINSTANCE HTinstance;
PRIVATE unsigned long HTwinMsg;
#else /* WWW_WIN_ASYNC */
PRIVATE fd_set FdArray[HTEvent_TYPES];
PRIVATE SOCKET MaxSock = 0;			  /* max socket value in use */
#endif /* !WWW_WIN_ASYNC */

/* ------------------------------------------------------------------------- */
/* 				DEBUG FUNCTIONS	    		             */
/* ------------------------------------------------------------------------- */

#ifdef HTDEBUG
PRIVATE void Event_trace (HTEvent * event)
{
    if (event) {
	HTTRACE(ALL_TRACE, "%8p: %3d %6d %8p %8p %8p" _
		event _ event->priority _ event->millis _ event->cbf _
		event->param _ event->request);
    }
}

PRIVATE void Event_traceHead (void)
{
    HTTRACE(ALL_TRACE, "     event: pri millis  callback   param    request  ");
}

PRIVATE void Timer_trace (HTTimer * timer)
{
    if (timer) {
	HTTRACE(ALL_TRACE, "%8p: %6d %ld %c %8p" _
		timer _
		HTTimer_expiresAbsolute(timer) _
		HTTimer_expiresRelative(timer) _
		HTTimer_isRelative(timer) ? 'R' : 'A' _
		HTTimer_callback(timer));
    }
}

PRIVATE void Timer_traceHead (void)
{
    HTTRACE(ALL_TRACE, "     timer: millis expires ?   param   callback  ");
}

/*
**  A simple debug function that dumps all the socket arrays
**  as trace messages
*/
PRIVATE void EventList_dump (void)
{
    int v = 0;
    HTList* cur;
    SockEvents * pres;
    HTTRACE(ALL_TRACE, "Event....... Dumping socket events\n");
    HTTRACE(ALL_TRACE, "soc ");
    Event_traceHead();
    HTTRACE(ALL_TRACE, " ");
    Timer_traceHead();
    HTTRACE(ALL_TRACE, "\n");
    for (v = 0; v < HT_M_HASH_SIZE; v++) {
	cur = HashTable[v];
	while ((pres = (SockEvents *) HTList_nextObject(cur))) {
	    int i;
	    HTTRACE(ALL_TRACE, "%3d \n" _ pres->s);
	    for (i = 0; i < HTEvent_TYPES; i++)
		if (pres->events[i]) {
		    static char * names[HTEvent_TYPES] = {"read", "writ", "xcpt"};
		    HTTRACE(ALL_TRACE, "%s " _ names[i]);
		    Event_trace(pres->events[i]);
		    HTTRACE(ALL_TRACE, " ");
		    Timer_trace(pres->timeouts[i]);
		    HTTRACE(ALL_TRACE, " ");
		}
	    HTTRACE(ALL_TRACE, "\n");
	}
    }
}

PRIVATE void fd_dump (SOCKET maxfs, fd_set * rset, fd_set * wset, fd_set * oset, 
		      struct timeval * wt)
{
    SOCKET cnt;

    /* Check read set */
    HTTRACE(THD_TRACE, "............ READ :");
    for (cnt=0; cnt<=maxfs; cnt++)
	if (FD_ISSET(cnt, rset)) HTTRACE(THD_TRACE, " %d" _ cnt);
    HTTRACE(THD_TRACE, "\n");

    /* Check write set */
    HTTRACE(THD_TRACE, "............ WRITE:");
    for (cnt=0; cnt<=maxfs; cnt++)
	if (FD_ISSET(cnt, wset)) HTTRACE(THD_TRACE, " %d" _ cnt);
    HTTRACE(THD_TRACE, "\n");

    /* Check oob set */
    HTTRACE(THD_TRACE, "............ OOB  :");
    for (cnt=0; cnt<=maxfs; cnt++)
	if (FD_ISSET(cnt, oset)) HTTRACE(THD_TRACE, " %d" _ cnt);
    HTTRACE(THD_TRACE, "\n");

    if (wt)
	HTTRACE(THD_TRACE, "............ Timeout is %ld s, %ld microsecs\n" _
		wt->tv_sec _ wt->tv_usec);
}
#endif /* HTDEBUG */

/* ------------------------------------------------------------------------- */
/*		           EVENT TIMING FUNCTIONS			     */
/* ------------------------------------------------------------------------- */

#ifdef WWW_WIN_ASYNC
PRIVATE BOOL Timer_setWindowsTimer (HTTimer * timer)
{
    UINT id;
    HWND hwnd = HTEventList_getWinHandle(&id);
    BOOL status = (SetTimer(hwnd, (UINT)timer, (UINT)HTTimer_getTime(timer), NULL) == 0) ? NO : YES;
    return status;
}

PRIVATE BOOL Timer_deleteWindowsTimer (HTTimer * timer)
{
    UINT id;
    HWND hwnd = HTEventList_getWinHandle(&id);
    BOOL status = (KillTimer(hwnd, (UINT)timer) == 0) ? NO : YES;
    return status;
}
#endif /* WWW_WIN_ASYNC */

/*
**  Event timeout handler
**  If an event didn't occur before the timeout then call it explicitly
**  indicating that it timed out.
*/
PRIVATE int EventListTimerHandler (HTTimer * timer, void * param, HTEventType type)
{
    SockEvents * sockp = (SockEvents *) param;
    HTEvent * event = NULL;

    /* Check for read timeout */
    if (sockp->timeouts[HTEvent_INDEX(HTEvent_READ)] == timer) {
	event = sockp->events[HTEvent_INDEX(HTEvent_READ)];
	HTTRACE(THD_TRACE, "Event....... READ timed out on %d.\n" _ sockp->s);
	return (*event->cbf) (sockp->s, event->param, HTEvent_TIMEOUT);
    }

    /* Check for write timeout */
    if (sockp->timeouts[HTEvent_INDEX(HTEvent_WRITE)] == timer) {
	event = sockp->events[HTEvent_INDEX(HTEvent_WRITE)];
	HTTRACE(THD_TRACE, "Event....... WRITE timed out on %d.\n" _ sockp->s);
	return (*event->cbf) (sockp->s, event->param, HTEvent_TIMEOUT);
    }

    /* Check for out-of-band data timeout */
    if (sockp->timeouts[HTEvent_INDEX(HTEvent_OOB)] == timer) {
	event = sockp->events[HTEvent_INDEX(HTEvent_OOB)];
	HTTRACE(THD_TRACE, "Event....... OOB timed out on %d.\n" _ sockp->s);
	return (*event->cbf) (sockp->s, event->param, HTEvent_TIMEOUT);
    }
    HTTRACE(THD_TRACE, "Event....... No event for timer %p with context %p\n" _ timer _ param);
    return HT_ERROR;
}

PUBLIC void CheckSockEvent (HTTimer * timer, HTTimerCallback * cbf, void * param)
{
    SockEvents * sockp = (SockEvents *)param;
    if (cbf == EventListTimerHandler && 
	sockp->timeouts[0] != timer && 
	sockp->timeouts[1] != timer && 
	sockp->timeouts[2] != timer) {
	HTDEBUGBREAK("Bad timer %p\n" _ timer);
    }
}

/* ------------------------------------------------------------------------- */
/*		             EVENT ORDERING STUFF			     */
/* ------------------------------------------------------------------------- */

PRIVATE SockEvents * SockEvents_get (SOCKET s, SockEvents_action action)
{
    long v = HASH(s);
    HTList* cur;
    SockEvents * pres;

    /* if the socket doesn't exists, don't do anything */
    if (s == INVSOC)
      return NULL;

    if (HashTable[v] == NULL) HashTable[v] = HTList_new();
    cur = HashTable[v];
    while ((pres = (SockEvents *) HTList_nextObject(cur)))
	if (pres->s == s) return pres;

    if (action == SockEvents_mayCreate) {
        if ((pres = (SockEvents *) HT_CALLOC(1, sizeof(SockEvents))) == NULL)
	    HT_OUTOFMEM("HTEventList_register");
	pres->s = s;
	HTList_addObject(HashTable[v], (void *)pres);
	return pres;
    }
    return NULL;
}

PRIVATE int EventOrder_add (SOCKET s, HTEventType type, ms_t now)
{
    EventOrder * pres;
    HTList * cur = EventOrderList;
    HTList * insertAfter = cur;
    SockEvents * sockp = SockEvents_get(s, SockEvents_find);
    HTEvent * event;

    if (sockp == NULL || (event = sockp->events[HTEvent_INDEX(type)]) == NULL) {
	HTTRACE(THD_TRACE, "EventOrder.. no event found for socket %d, type %s.\n" _
		s _ HTEvent_type2str(type));
	return HT_ERROR;
    }

    /*	Fixup the timeout */
    if (sockp->timeouts[HTEvent_INDEX(type)])
	HTTimer_refresh(sockp->timeouts[HTEvent_INDEX(type)], now);

    /* Look to see if it's already here from before */
    while ((pres = (EventOrder *) HTList_nextObject(cur))) {
	if (pres->s == s && pres->event == event && pres->type == type) {
	    pres->skipped++;
	    return HT_OK;
	}
	if (pres->event->priority+pres->skipped > event->priority)
	    insertAfter = cur;
    }

    /* Create a new element */
    if ((pres = (EventOrder *) HT_CALLOC(1, sizeof(EventOrder))) == NULL)
	HT_OUTOFMEM("EventOrder_add");
    pres->event = event;
    pres->s = s;
    pres->type = type;
    HTList_addObject(insertAfter, (void *)pres);
    return HT_OK;
}

PUBLIC int EventOrder_executeAndDelete (void) 
{
    HTList * cur = EventOrderList;
    EventOrder * pres;
    int i = 0;
    HTTRACE(THD_TRACE, "EventOrder.. execute ordered events\n");
    if (cur == NULL) return NO;
    while ((pres=(EventOrder *) HTList_removeLastObject(cur)) && i<EVENTS_TO_EXECUTE) {
	HTEvent * event = pres->event;
	int ret;
	HTTRACE(THD_TRACE, "EventList... calling socket %d, request %p handler %p type %s\n" _ 
		    pres->s _ (void *) event->request _ 
		    (void *) event->cbf _ HTEvent_type2str(pres->type));
	ret = (*pres->event->cbf)(pres->s, pres->event->param, pres->type);
	HT_FREE(pres);
	if (ret != HT_OK) return ret;
	i++;
    }
    return HT_OK;
}

PRIVATE BOOL EventOrder_clearAll (void)
{
    HTList * cur = EventOrderList;
    EventOrder * pres;
    HTTRACE(THD_TRACE, "EventOrder.. Clearing all ordered events\n");
    if (cur) {
	while ((pres = (EventOrder *) HTList_nextObject(cur)))
	    HT_FREE(pres);
	return YES;
    }
    return NO;
}

PUBLIC BOOL EventOrder_deleteAll (void) 
{
    EventOrder_clearAll();
    HTList_delete(EventOrderList);
    EventOrderList = NULL;
    return YES;
}

/* ------------------------------------------------------------------------- */
/*				EVENT REGISTRATION			     */
/* ------------------------------------------------------------------------- */

/*
** ResetMaxSock - reset the value of the maximum socket in use 
*/
#ifndef WWW_WIN_ASYNC
PRIVATE void __ResetMaxSock (void)
{
    SOCKET cnt;
    SOCKET t_max = 0;
    SOCKET old_max = MaxSock;
    for (cnt = 0 ; cnt <= MaxSock; cnt++) { 
	if (FD_ISSET(cnt, (FdArray + HTEvent_INDEX(HTEvent_READ))) ||
	    FD_ISSET(cnt, (FdArray + HTEvent_INDEX(HTEvent_WRITE))) ||
	    FD_ISSET(cnt, (FdArray + HTEvent_INDEX(HTEvent_OOB))))
  	    if (cnt > t_max) t_max = cnt;
    }
    MaxSock = t_max+1;
    HTTRACE(THD_TRACE, "Event....... Reset MaxSock from %u to %u\n" _ old_max _ MaxSock);
    return;
}  
#endif /* !WWW_WIN_ASYNC */

PRIVATE int EventList_remaining (SockEvents * pres)
{
    int ret = 0;
    int i;
    for (i = 0; i < HTEvent_TYPES; i++)
	if (pres->events[i] != NULL)
	    ret |= 1<<i;
    return ret;
}

/*
**  For a given socket, reqister a request structure, a set of operations, 
**  a HTEventCallback function, and a priority. For this implementation, 
**  we allow only a single HTEventCallback function for all operations.
**  and the priority field is ignored.
*/
PUBLIC int HTEventList_register (SOCKET s, HTEventType type, HTEvent * event)
{
    int newset = 0;
    SockEvents * sockp;
    HTTRACE(THD_TRACE, "Event....... Register socket %d, request %p handler %p type %s at priority %d\n" _ 
		s _ (void *) event->request _ 
		(void *) event->cbf _ HTEvent_type2str(type) _ 
		(unsigned) event->priority);
    if (s==INVSOC || HTEvent_INDEX(type) >= HTEvent_TYPES)
	return 0;

    /*
    ** Insert socket into appropriate file descriptor set. We also make sure
    ** that it is registered in the global set.
    */
    HTTRACE(THD_TRACE, "Event....... Registering socket for %s\n" _ HTEvent_type2str(type));
    sockp = SockEvents_get(s, SockEvents_mayCreate);
    sockp->s = s;
    sockp->events[HTEvent_INDEX(type)] = event;
    newset = EventList_remaining(sockp);
#ifdef WWW_WIN_ASYNC
    if (WSAAsyncSelect(s, HTSocketWin, HTwinMsg, HTEvent_BITS(newset)) < 0) {
        HTTRACE(THD_TRACE, "Event....... WSAAsyncSelect returned `%s'!" _ HTErrnoString(socerrno));
	return HT_ERROR;
    }
#else /* WWW_WIN_ASYNC */
    FD_SET(s, FdArray+HTEvent_INDEX(type));

    HTTRACEDATA((char *) FdArray+HTEvent_INDEX(type), 8, "HTEventList_register: (s:%d)" _ s);

    if (s > MaxSock) {
	MaxSock = s ;
	HTTRACE(THD_TRACE, "Event....... New value for MaxSock is %d\n" _ MaxSock);
    }
#endif /* !WWW_WIN_ASYNC */

    /*
    **  If the timeout has been set (relative in millis) then we register 
    **  a new timeout for this event unless we already have a timer.
    */
    if (event->millis >= 0) {
	sockp->timeouts[HTEvent_INDEX(type)] =
	    HTTimer_new(sockp->timeouts[HTEvent_INDEX(type)],
			EventListTimerHandler, sockp, event->millis, YES, YES);
    }

    return HT_OK;
}

/*
** Remove the registered information for the specified socket for the actions 
** specified in ops. if no actions remain after the unregister, the registered
** info is deleted, and, if the socket has been registered for notification, 
** the HTEventCallback will be invoked.
*/
PUBLIC int HTEventList_unregister (SOCKET s, HTEventType type) 
{
    long 		v = HASH(s);
    HTList * 		cur = HashTable[v];
    HTList * 		last = cur;
    SockEvents *	pres;
    int			ret = HT_ERROR;

    /* if the socket doesn't exists, don't do anything */
    if (s == INVSOC)
      return HT_OK;

    while (cur && (pres = (SockEvents *) HTList_nextObject(cur))) {
        if (pres->s == s) {
	    int	remaining = 0;

	    /*
	    **  Unregister the event from this action
	    */
	    pres->events[HTEvent_INDEX(type)] = NULL;
            remaining = EventList_remaining(pres);

	    /*
	    **  Check to see of there was a timeout connected with the event.
	    **  If so then delete the timeout as well.
	    */
	    {
		HTTimer * timer = pres->timeouts[HTEvent_INDEX(type)];
                if (timer) HTTimer_delete(timer);
                pres->timeouts[HTEvent_INDEX(type)] = NULL;