/*
*
* (c) COPYRIGHT MIT and INRIA, 1996.
* Please first read the full copyright statement in file COPYRIGHT.
*
*/
/*
* AHTBridge.c : This module implements the callback setup and
* handlers between the Xt, libwww, and Amaya procedures. It's responsible
* for assigning, modifying, and supressing Xt events to the active
* requests.
*
* Author: J Kahan
*
*/
#define EXPORT extern
#include "amaya.h"
#include "AHTBridge_f.h"
#include "AHTFWrite_f.h"
#include "query_f.h"
#include "answer_f.h"
#ifdef WWW_XWINDOWS
/* Amaya's X appcontext */
extern XtAppContext app_cont;
#endif
#ifndef HACK_WWW
extern HTEventCallback *HTEvent_Retrieve (SOCKET, SockOps, HTRequest ** arp);
#endif
/*
* Private functions
*/
#ifdef __STDC__
static void RequestKillReadXtevent (AHTReqContext *);
static void RequestKillWriteXtevent (AHTReqContext *);
static void RequestKillExceptXtevent (AHTReqContext *);
#else
static void RequestKillReadXtevent ();
static void RequestKillWriteXtevent ();
static void RequestKillExceptXtevent ();
#endif
/*
* Private variables
*/
/*
* this set of SockOps map our WinSock "socket event SockOps" into
* our read and write sets. Note that under the canonical Unix model,
* a non-blocking socket passed to an accept() call will appear as readable,
* whilst a non-blocking call to connect() will appear as writeable. In add.
* if the connection has been closed, the socket will appear readable under
* BSD Unix semantics
*/
static const SockOps ReadBits = FD_READ | FD_ACCEPT | FD_CLOSE;
static const SockOps WriteBits = FD_WRITE | FD_CONNECT;
static const SockOps ExceptBits = FD_OOB;
/*
* Private functions
*/
/*--------------------------------------------------------------------
AHTCallback_bridge
this function acts as a bridge between Xt and libwww. From the Xt
point of view, this function is the callback handler whenever there's
any activity on the sockets associated with the active requests. From
the libwww point of view, this is the function that takes the initiative
to invoke the callback function associated with an active request,
whenever there's an activity in the socket associated to it.
In this latter aspect, this function is similar to the library's
own __DoCallback() function.
Upon activation, the function looks up the request associated with the
active socket and then looks up the cbf associated with that request.
Upon completion of the execution of the request's cbf, it verifies
the state of the request and, if it's an asynchronous request, deletes
the memory allocated to it.
-------------------------------------------------------------------*/
#ifdef __STDC__
void *AHTCallback_bridge (caddr_t cd, int *s, XtInputId * id)
#else
void *AHTCallback_bridge (cd, s, id)
caddr_t cd;
int *s;
XtInputId *id;
#endif /* __STDC__ */
{
int status; /* the status result of the libwwww call */
HTRequest *rqp = NULL;
AHTReqContext *me;
SockOps ops;
/* Libwww 5.0a does not take into account the ops parameter
in the invocation of for this function call */
#ifdef HACK_WWW
HTEventCallback *cbf;
#else
HTEventCallback *cbf;
ops = FD_WRITE;
cbf = (HTEventCallback *) __RetrieveCBF (*s, ops, &rqp);
#endif
me = HTRequest_context (rqp);
if (THD_TRACE)
fprintf (stderr, "AHTBridge: Processing url %s \n", me->urlName);
#ifdef WWW_XWINDOWS
switch ((XtInputId) cd)
{
case XtInputWriteMask:
ops = me->write_ops;
ops = FD_WRITE;
break;
case XtInputExceptMask:
ops = me->except_ops;
ops = FD_OOB;
break;
default:
case XtInputReadMask:
ops = me->read_ops;
ops = FD_READ;
break;
} /* switch */
#endif /* WWW_XWINDOWS */
/* verify if there's any callback associated with the request */
if (!cbf || !rqp || rqp->priority == HT_PRIORITY_OFF)
{
if (THD_TRACE)
HTTrace ("Callback.... No callback found\n");
/* put some more code to correctly destroy this request */
return (0);
}
/* Invokes the callback associated to the requests */
/* first we change the status of the request, to say it
has entered a critical section */
if((HTRequest_outputStream(me->request) == (HTStream *) NULL))
fprintf(stderr,"\n **ERROR** opening %s\n\n",me->urlName);
me->reqStatus = HT_BUSY;
if ((status = (*cbf) (*s, rqp, ops)) != HT_OK)
HTTrace ("Callback.... received != HT_OK");
/* Several states can happen after this callback. They
* are indicated by the me->reqStatus structure member and
* the fds external variables. The following lines examine
* the states and correspondly update the Xt event register
*
* Regarding the me->reqStatus member, we have the following
* possible states:
*
* HT_BUSY: Request has blocked
* HT_WAITING: Request has been reissued
* HT_ABORT: Request has been stopped
* HT_END: Request has ended
*/
#ifdef WWW_XWINDOWS
if (me->reqStatus == HT_ABORT)
/* Has the user stopped the request? */
{
me->reqStatus = HT_WAITING;
StopRequest (me->docid);
if (THD_TRACE)
fprintf (stderr, "(BF) removing Xtinput %lu !RWE (Stop buttonl), sock %d\n", me->read_xtinput_id, *s);
return (0);
}
#endif /* WWW_XWINDOWS */
if (me->reqStatus == HT_WAITING)
/* the request is being reissued */
{
/*
* (1) The old request has ended and the library
* assigned the old socket number to a pending
* request.
*
* (2) The request has been reissued after an
* authentication or redirection directive and
* we are using the same old socket number.
*/
if (THD_TRACE)
fprintf (stderr, "*** detected a reissue of request \n");
return (0);
}
/* we verify if the request exists. If it has ended, we will have
a reqStatus with an HT_END value */
if ((me->request->net == (HTNet *) NULL) || (me->reqStatus == HT_END || me->reqStatus == HT_ERR))
/* request has ended */
{
#ifdef WWW_XWINDOWS
if (THD_TRACE)
fprintf (stderr, "(BF) removing Xtinput %lu !RWE, sock %d (Request has ended)\n", *id, *s);
#endif
if ((me->mode & AMAYA_ASYNC) || (me->mode & AMAYA_IASYNC))
/* free the memory allocated for async requests */
{
AHTPrintPendingRequestStatus (me->docid, YES);
AHTReqContext_delete (me);
}
else if (me->reqStatus != HT_END && HTError_hasSeverity (HTRequest_error (me->request), ERR_NON_FATAL))
/* did the SYNC request end because of an error? If yes, report it back to the caller */
me->reqStatus = HT_ERR;
return (0);
}
/* The request is still alive, so change it's status to indicate it's out of the
critical section */
me->reqStatus = HT_WAITING;
return (0);
}
/*----------------------------------------------------------------
Add_NewSocket_to_Loop
when there are more open requests than available sockets, the
requests are put in a "pending state." When a socket becomes
available, libwww associates it with a pending request and then
calls this callback function. This function is responsible for
opening the temporary file where the GET and POST results
will be stored. The function is also responsible for
registering the socket with the Xt event loop.
Consult the libwww manual for more details on the signature
of this function.
----------------------------------------------------------------*/
#ifdef __STDC__
int Add_NewSocket_to_Loop (HTRequest * request, HTAlertOpcode op, int msgnum, const char *dfault, void *input, HTAlertPar * reply)
#else
int Add_NewSocket_to_Loop (request, op, msgnum, dfault, input, reply)
HTRequest *request;
HTAlertOpcode op;
int msgnum;
const char *dfault;
void *input;
HTAlertPar *reply;
#endif /* __STDC__ */
{
AHTReqContext *me = HTRequest_context (request);
if (me->reqStatus == HT_BUSY)
/* request was aborted and now is is being reissued */
{
rewind (me->output);
HTRequest_setOutputStream (me->request, AHTFWriter_new (me->request, me->output, YES));
} else if (me->reqStatus == HT_NEW_PENDING)
{
/* we are dequeing a pending request */
if (me->outputfile && (me->output = fopen (me->outputfile, "w")) == NULL)
{
/* the request is associated with a file */
me->outputfile[0] = '\0'; /* file could not be opened */
TtaSetStatus (me->docid, 1, TtaGetMessage (AMAYA, AM_CANNOT_CREATE_FILE),
me->outputfile);
me->reqStatus = HT_ERR;
return (HT_ERROR);
}
if (THD_TRACE)
fprintf (stderr, "Add_NewSocket_to_Loop: Activating pending %s . Open fd %d\n", me->urlName, (int) me->output);
HTRequest_setOutputStream (me->request,
AHTFWriter_new (me->request, me->output, YES));
}
/*change the status of the request */
me->reqStatus = HT_WAITING;
if (THD_TRACE)
fprintf (stderr, "(Activating a pending request\n");
return (HT_OK);
}
/*----------------------------------------------------------------------
AHTEvent_register
callback called by libwww whenever a socket is open and associated
to a request. It sets the pertinent Xt events so that the Xt Event
loops gets an interruption whenever there's action of the socket.
In addition, it registers the request with libwww.
----------------------------------------------------------------------*/
#ifdef __STDC__
int AHTEvent_register (SOCKET sock, HTRequest * rqp, SockOps ops, HTEventCallback * cbf, HTPriority p)
#else
int AHTEvent_register (sock, rqp, ops, cbf, p)
SOCKET sock;
HTRequest *rqp;
SockOps ops;
HTEventCallback *cbf;
HTPriority p;
#endif /* __STDC__ */
{
AHTReqContext *me; /* current request */
int status; /* libwww status associated with the socket number */
if (sock == INVSOC)
return (0);
/* get the request associated to the socket number */
if ((status = HTEventrg_register (sock, rqp, ops,
cbf, p)) != HT_OK)
return (status);
if (rqp)
{
me = HTRequest_context (rqp);
/* verify if we need to open the fd */
if (me->reqStatus == HT_NEW_PENDING)
{
/* we are opening a pending request */
if ((me->output = fopen (me->outputfile, "w")) == NULL)
{
me->outputfile[0] = '\0'; /* file could not be opened */
TtaSetStatus (me->docid, 1, TtaGetMessage (AMAYA, AM_CANNOT_CREATE_FILE),
me->outputfile);
me->reqStatus = HT_ERR;
return (HT_ERROR);
}
HTRequest_setOutputStream (me->request,
AHTFWriter_new (me->request, me->output, YES));
me->reqStatus = HT_WAITING;
if (THD_TRACE)
fprintf (stderr, "AHTEvent_register: Activating pending request url %s, fd %d\n", me->urlName, (int) me->output);
}
if (THD_TRACE)
fprintf (stderr, "AHTEvent_register: url %s, sock %d, ops %lu \n",
me->urlName, sock, ops);
/* add the input */
if (me->reqStatus == HT_NEW)
me->reqStatus = HT_WAITING;
if (ops & ReadBits)
{
me->read_ops = ops;
#ifdef WWW_XWINDOWS
if (me->read_xtinput_id)
XtRemoveInput (me->read_xtinput_id);
me->read_xtinput_id =
XtAppAddInput (app_cont,
sock,
(XtPointer) XtInputReadMask,
(XtInputCallbackProc) AHTCallback_bridge,
(XtPointer) XtInputReadMask);
if (THD_TRACE)
fprintf (stderr, "(BT) adding Xtinput %lu Socket %d R\n",
me->read_xtinput_id, sock);
#endif /* WWW_XWINDOWS */
}
if (ops & WriteBits)
{
me->write_ops = ops;
#ifdef WWW_XWINDOWS
if (me->write_xtinput_id)
XtRemoveInput (me->write_xtinput_id);
me->write_xtinput_id = XtAppAddInput (app_cont, sock,
(XtPointer) XtInputWriteMask,
(XtInputCallbackProc) AHTCallback_bridge,
(XtPointer) XtInputWriteMask);
if (THD_TRACE)
fprintf (stderr, "(BT) adding Xtinput %lu Socket %d W\n",
me->write_xtinput_id, sock);
#endif /* WWW_XWINDOWS */
}
if (ops & ExceptBits)
{
me->except_ops = ops;
#ifdef WWW_XWINDOWS
if (me->except_xtinput_id)
XtRemoveInput (me->except_xtinput_id);
me->except_xtinput_id = XtAppAddInput (app_cont, sock,
(XtPointer) XtInputExceptMask,
(XtInputCallbackProc) AHTCallback_bridge,
(XtPointer) XtInputExceptMask);
if (THD_TRACE)
fprintf (stderr, "(BT) adding Xtinput %lu Socket %d E\n", me->except_xtinput_id, sock);
#endif /* WWW_XWINDOWS */
}
}
return (status);
}
/*----------------------------------------------------------------------
AHTEvent_unregister
callback called by libwww each time a request is unregistered. This
function takes care of unregistering the pertinent Xt events
associated with the request's socket. In addition, it unregisters
the request from libwww.
----------------------------------------------------------------------*/
#ifdef __STDC__
int AHTEvent_unregister (SOCKET sock, SockOps ops)
#else
int AHTEvent_unregister (sock, ops)
SOCKET sock;
SockOps ops;
#endif /* __STDC__ */
{
int status;
HTRequest *rqp = NULL;
AHTReqContext *me;
/* Libwww 5.0a does not take into account the third parameter
** for this function call */
HTEventCallback *cbf = (HTEventCallback *) __RetrieveCBF (sock, (SockOps) NULL, &rqp);
#ifdef WWW_XWINDOWS
if (cbf)
{
if (rqp)
{
me = HTRequest_context (rqp);
if (ops & ReadBits)
RequestKillReadXtevent (me);
if (ops & WriteBits)
RequestKillWriteXtevent (me);
if (ops & ExceptBits)
RequestKillExceptXtevent (me);
}
}
status = HTEventrg_unregister (sock, ops);
#endif /* WWW_XWINDOWS */
return (status);
}
/*----------------------------------------------------------------------
RequestKillAllXtevents
front-end for kill all Xt events associated with the request pointed
to by "me".
----------------------------------------------------------------------*/
#ifdef __STDC__
void RequestKillAllXtevents (AHTReqContext * me)
#else
void RequestKillAllXtevents (me)
AHTReqContext *me;
#endif /* __STDC__ */
{
#ifdef WWW_XWINDOWS
if (THD_TRACE)
fprintf (stderr, "Request_kill: Clearing Xtinputs\n");
RequestKillReadXtevent (me);
RequestKillWriteXtevent (me);
RequestKillExceptXtevent (me);
#endif /* WWW_XWINDOWS */
}
/*----------------------------------------------------------------------
RequestKillReadXtevent
kills any read Xt event associated with the request pointed to by "me".
----------------------------------------------------------------------*/
#ifdef __STDC__
static void RequestKillReadXtevent (AHTReqContext * me)
#else
static void RequestKillReadXtevent (me)
AHTReqContext *me;
#endif /* __STDC__ */
{
#ifdef WWW_XWINDOWS
if (me->read_xtinput_id)
{
if (THD_TRACE)
fprintf (stderr, "Request_kill: Clearing Read Xtinputs%lu\n", me->read_xtinput_id);
XtRemoveInput (me->read_xtinput_id);
me->read_xtinput_id = (XtInputId) NULL;
}
#endif /* WWW_XWINDOWS */
}
/*----------------------------------------------------------------------
RequestKillWriteXtevent
kills any write Xt event associated with the request pointed to
by "me".
----------------------------------------------------------------------*/
#ifdef __STDC__
static void RequestKillWriteXtevent (AHTReqContext * me)
#else
static void RequestKillWriteXtevent (me)
AHTReqContext *me;
#endif /* __STDC__ */
{
#ifdef WWW_XWINDOWS
if (me->write_xtinput_id)
{
if (THD_TRACE)
fprintf (stderr, "Request_kill: Clearing Write Xtinputs %lu\n", me->write_xtinput_id);
XtRemoveInput (me->write_xtinput_id);
me->write_xtinput_id = (XtInputId) NULL;
}
#endif /* WWW_XWINDOWS */
}
/*----------------------------------------------------------------------
RequestKillExceptXtevent
kills any exception Xt event associated with the request pointed to
by "me".
----------------------------------------------------------------------*/
#ifdef __STDC__
static void RequestKillExceptXtevent (AHTReqContext * me)
#else
static void RequestKillExceptXtevent (me)
AHTReqContext *me;
#endif /* __STDC__ */
{
#ifdef WWW_XWINDOWS
if (me->except_xtinput_id)
{
if (THD_TRACE)
fprintf (stderr, "Request_kill: Clearing Except Xtinputs %lu\n", me->except_xtinput_id);
XtRemoveInput (me->except_xtinput_id);
me->except_xtinput_id = (XtInputId) NULL;
}
#endif /* WWW_XWINDOWS */
}
/*
End of Module AHTBridge.c
*/
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