/* * * (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. -----------------------------------------------------------------------*/ #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__ XtInputCallbackProc AHTCallback_bridge (caddr_t cd, int *s, XtInputId * id) #else XtInputCallbackProc AHTCallback_bridge (cd, s, id) caddr_t cd; int *s; XtInputId *id; #endif /* __STDC__ */ /** JK: 26/Dec/96: Took out this code as Cextract has problems to generate a prototype when there are 2 imbricated ifdefs. ***/ #ifdef 0 /* Windows prototype */ /* some winproc someday? */ LONG AHTCallback_bridge (caddr_t cd, int *s) #endif /* !WWW_XWINDOWS */ { 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 = (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 */ 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_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 */