ipc/dde_proc.c

   1 /***************************************************************************
   2  * Copyright 1995, Technion, Israel Institute of Technology
   3  * Electrical Eng, Software Lab.
   4  * Author:    Michael Veksler.
   5  ***************************************************************************
   6  * File:      dde_proc.c
   7  * Purpose :  DDE signals and processes functionality for DDE
   8  ***************************************************************************
   9  */
  10 #ifdef CONFIG_IPC
  11
  12 #if defined(__FreeBSD__) || defined(__NetBSD__)
  13 #define msgbuf mymsg
  14 #endif
  15
  16 #include <sys/time.h>
  17 #include <unistd.h>
  18 #include <stdlib.h>
  19 #include <signal.h>
  20 #include <errno.h>
  21 #include <sys/msg.h>
  22 #include "wintypes.h"
  23 #include "win.h"
  24 #include "shm_semaph.h"
  25 #include "shm_main_blk.h"
  26 #include "dde_proc.h"
  27 #include "dde_mem.h"
  28 #include "dde.h"
  29 #include "stddebug.h"
  30 #include "debug.h"
  31 #include "xmalloc.h"
  32
  33 int curr_proc_idx= -1;
  34
  35 enum stop_wait_op stop_wait_op=CONT;
  36 int had_SIGUSR2 = 0;
  37 sigjmp_buf env_get_ack;
  38 sigjmp_buf env_wait_x;
  39
  40 #define IDX_TO_HWND(idx)  (0xfffe - (idx))
  41 #define HWND_TO_IDX(wnd)  (0xfffe - (wnd))
  42 #define DDE_WIN_INFO(win) ( main_block->windows[HWND_TO_IDX(win)] )
  43 #define DDE_WIN2PROC(win) ( DDE_WIN_INFO(win).proc_idx )
  44 #define DDE_IsRemoteWindow(win)  (  (win)<0xffff && (win)>=(0xffff-DDE_PROCS))
  45 #define DDE_SEND 1
  46 #define DDE_POST 2
  47 #define DDE_ACK  3
  48 #define DDE_MSG_SIZE   sizeof(MSG)
  49 #define FREE_WND (WORD)(-2)
  50 #define DELETED_WND (WORD)(-3)
  51 #if defined(DEBUG_MSG) || defined(DEBUG_RUNTIME)
  52 static char *msg_type[4]={"********", "DDE_SEND", "DDE_POST", "DDE_ACK"};
  53 #endif
  54
  55 struct msg_dat {
  56         struct msgbuf dat;
  57         char filler[DDE_MSG_SIZE];
  58 } ;
  59
  60 typedef struct fifo_element {
  61         int value;
  62         struct fifo_element *next;
  63 } fifo_element;
  64
  65 struct fifo {
  66         fifo_element *first;       /* first element in the fifo or NULL */
  67         fifo_element *last;        /* last element in the fifo or NULL */
  68 };
  69 static struct fifo fifo = {NULL,NULL};
  70
  71 void dde_proc_delete(int proc_idx);
  72
  73 void dde_proc_add_fifo(int val)
  74 {
  75   fifo_element *created;
  76
  77   created= (fifo_element*) xmalloc( sizeof(fifo_element) );
  78   created->value = val;
  79   created->next = NULL;
  80
  81   if (fifo.first==NULL)
  82      fifo.first= created;
  83   else
  84      fifo.last->next= created;
  85   fifo.last = created;
  86 }
  87
  88 /* get an item from the fifo, and return it.
  89  * If fifo is empty, return -1
  90  */
  91 int dde_proc_shift_fifo()
  92 {
  93   int val;
  94   fifo_element *deleted;
  95
  96   if (fifo.first == NULL)
  97      return -1;
  98
  99   deleted= fifo.first;
 100   val= deleted->value;
 101   fifo.first= deleted->next;
 102   if (fifo.first == NULL)
 103      fifo.last= NULL;
 104
 105   free(deleted);
 106   return val;
 107 }
 108
 109 static void print_dde_message(char *desc, MSG *msg);
 110
 111 /* This should be run only when main_block is first allocated.  */
 112 void dde_proc_init(dde_proc proc)
 113 {
 114   int proc_num;
 115
 116   for (proc_num=0 ; proc_num<DDE_PROCS ; proc_num++, proc++) {
 117      proc->msg=-1;
 118      proc->sem=-1;
 119      proc->shmid=-1;
 120      proc->pid=-1;
 121   }
 122 }
 123
 124 /* add current process to the list of processes */
 125 void dde_proc_add(dde_proc procs)
 126 {
 127   dde_proc proc;
 128   int proc_idx;
 129   dprintf_dde(stddeb,"dde_proc_add(..)\n");
 130   shm_write_wait(main_block->sem);
 131
 132   /* find free proc_idx and allocate it */
 133   for (proc_idx=0, proc=procs ; proc_idx<DDE_PROCS ; proc_idx++, proc++)
 134      if (proc->pid==-1)
 135         break;                     /* found! */
 136
 137   if (proc_idx<DDE_PROCS) {        /* got here beacuse a free was found ? */
 138      dde_msg_setup(&proc->msg);
 139      proc->pid=getpid();
 140      curr_proc_idx=proc_idx;
 141      shm_sem_init(&proc->sem);
 142   }
 143   else  {
 144      fflush(stdout);
 145      fprintf(stderr,"dde_proc_add: Can't allocate process\n");
 146   }
 147   shm_write_signal(main_block->sem);
 148 }
 149
 150 /* wait for dde - acknowledge message - or timout */
 151 static BOOL get_ack()
 152 {
 153     struct timeval timeout;
 154     int size;
 155     struct msg_dat ack_buff;
 156
 157     /* timeout after exactly one seconf */
 158     timeout.tv_sec = 1;
 159     timeout.tv_usec = 0;
 160
 161     sigsetjmp(env_get_ack, 1);
 162     /* get here after normal execution, or after siglongjmp */
 163
 164     do {                           /* loop to wait for DDE_ACK */
 165        had_SIGUSR2=0;
 166        stop_wait_op=CONT;          /*  sensitive code: disallow siglongjmp */
 167        size= msgrcv( main_block->proc[curr_proc_idx].msg , &ack_buff.dat,
 168                      1, DDE_ACK, IPC_NOWAIT);
 169        if (size>=0) {
 170           dprintf_msg(stddeb,"get_ack: received DDE_ACK message\n");
 171           return TRUE;
 172        }
 173        if (DDE_GetRemoteMessage()) {
 174              had_SIGUSR2=1;  /* might have recieved SIGUSR2 */
 175        }
 176        stop_wait_op=STOP_WAIT_ACK; /* allow siglongjmp */
 177
 178     } while (had_SIGUSR2);         /* loop if SIGUSR2 was recieved */
 179
 180     /* siglongjmp should be enabled at this moment */
 181     select( 0, NULL, NULL, NULL, &timeout );
 182     stop_wait_op=CONT;             /* disallow further siglongjmp */
 183
 184     /* timeout !! (otherwise there would have been a siglongjmp) */
 185     return FALSE;
 186 }
 187
 188 /* Transfer one message to a given process */
 189 static BOOL DDE_DoOneMessage (int proc_idx, int size, struct msgbuf *msgbuf)
 190 {
 191   dde_proc proc= &main_block->proc[ proc_idx ];
 192
 193
 194   if (proc_idx == curr_proc_idx)
 195      return FALSE;
 196
 197   if (kill(proc->pid,0) < 0) {
 198      /* pid does not exist, or not our */
 199      dde_proc_delete(proc_idx);
 200      return FALSE;
 201   }
 202
 203   if (debugging_dde) {
 204      MSG *msg=(MSG*) &msgbuf->mtext;
 205      char *title;
 206      if (msgbuf->mtype==DDE_SEND)
 207         title="sending dde:";
 208      else if (msgbuf->mtype==DDE_POST)
 209         title="posting dde:";
 210      else
 211         title=NULL;
 212      if (title)
 213          print_dde_message(title, msg);
 214      else
 215        fprintf(stddeb,"Unknown message type=0x%lx\n",msgbuf->mtype);
 216   }
 217   dprintf_msg(stddeb,
 218               "DDE_DoOneMessage: to proc_idx=%d (pid=%d), queue=%u\n",
 219               proc_idx, proc->pid, (unsigned)proc->msg);
 220   if ( proc->msg != -1) {
 221      dprintf_msg(stddeb, "DDE_DoOneMessage: doing...(type=%s)\n",
 222                  msg_type[msgbuf->mtype]);
 223      size=msgsnd (proc->msg, msgbuf, size, 0);
 224
 225      if (size<0) {
 226          fflush(stdout);
 227          perror("msgsnd");
 228      }
 229      kill(proc->pid,SIGUSR2);      /* tell the process there is a message */
 230
 231      dprintf_msg(stddeb,"DDE_DoOneMessage: "
 232                  "Trying to get acknowledgment from msg queue=%d\n",
 233                  proc->msg);
 234      Yield();                   /* force task switch, and */
 235                                 /* acknowledgment sending */
 236      if (get_ack()) {
 237         return TRUE;
 238      } else {
 239         fflush(stdout);
 240         fprintf(stderr,"get_ack: DDE_DoOneMessage: timeout\n");
 241         return FALSE;
 242      }
 243   }
 244   else {
 245      dprintf_msg(stddeb,"DDE_DoOneMessage: message not sent, "
 246                  "target has no message queue\n");
 247      return FALSE;
 248   }
 249 }
 250
 251 /* Do some sort of premitive hash table */
 252 static HWND HWND_Local2Remote(HWND orig)
 253 {
 254   int dde_wnd_idx;
 255   int deleted_idx= -1;
 256   WND_DATA *tested;
 257   WND_DATA *deleted= NULL;
 258   int i;
 259
 260   dde_wnd_idx= orig % DDE_WINDOWS;
 261   for ( i=0 ; i < DDE_WINDOWS ; i++, dde_wnd_idx++) {
 262     if (dde_wnd_idx >= DDE_WINDOWS)
 263       dde_wnd_idx -= DDE_WINDOWS; /* wrap-around */
 264
 265     tested= &main_block->windows[ dde_wnd_idx ];
 266     if (tested->proc_idx == FREE_WND)
 267       break;
 268
 269     if (deleted == NULL && tested->proc_idx == DELETED_WND) {
 270       deleted= tested;
 271       deleted_idx= dde_wnd_idx;
 272     } else if (tested->wnd == orig && tested->proc_idx == curr_proc_idx) {
 273       return IDX_TO_HWND(dde_wnd_idx);
 274     }
 275   }
 276   if (deleted != NULL)  {       /* deleted is preferable */
 277     /* free item, allocate it */
 278     deleted->proc_idx= curr_proc_idx;
 279     deleted->wnd = orig;
 280     return IDX_TO_HWND(deleted_idx);
 281   }
 282   if (tested->proc_idx == FREE_WND) {
 283     tested->proc_idx= curr_proc_idx;
 284     tested->wnd = orig;
 285     return IDX_TO_HWND(dde_wnd_idx);
 286   }
 287
 288   fprintf(stderr,
 289           "HWND_Local2Remote: Can't map any more windows to DDE windows\n");
 290   return 0;
 291 }
 292
 293 static BOOL DDE_DoMessage( MSG *msg, int type )
 294 {
 295   int proc_idx;
 296
 297   MSG *remote_message;
 298   struct msg_dat msg_dat;
 299   BOOL success;
 300
 301   if (msg->wParam == 0)
 302       return FALSE;
 303
 304   if (main_block==NULL) {
 305     if (msg->message >=  WM_DDE_FIRST && msg->message <= WM_DDE_LAST)
 306       DDE_IPC_init();
 307     else
 308       return FALSE;
 309   }
 310
 311
 312   if (msg->wParam == (HWND)-1)
 313      return FALSE;
 314
 315   if ( ! DDE_IsRemoteWindow(msg->hwnd) && msg->hwnd!= (HWND)-1)
 316      return FALSE;
 317
 318   dprintf_msg(stddeb, "%s: DDE_DoMessage(hwnd=0x%x,msg=0x%x,..)\n",
 319               msg_type[type], (int)msg->hwnd,(int)msg->message);
 320
 321
 322   dprintf_msg(stddeb,
 323               "DDE_DoMessage(hwnd=0x%x,msg=0x%x,..) // HWND_BROADCAST !\n",
 324               (int)msg->hwnd,(int)msg->message);
 325   remote_message=(void*)&msg_dat.dat.mtext;
 326
 327   memcpy(remote_message, msg, sizeof(*msg));
 328   remote_message->wParam= HWND_Local2Remote(msg->wParam);
 329   if (remote_message->wParam == 0)
 330     return FALSE;
 331
 332   msg_dat.dat.mtype=type;
 333
 334   if (msg->hwnd == (HWND)-1) {
 335      success= FALSE;
 336      for ( proc_idx=0; proc_idx < DDE_PROCS ; proc_idx++) {
 337         if (proc_idx == curr_proc_idx)
 338            continue;
 339         if (main_block->proc[ proc_idx ].msg != -1)
 340            success|=DDE_DoOneMessage(proc_idx, DDE_MSG_SIZE, &msg_dat.dat);
 341      }
 342      return success;
 343   } else {
 344      return DDE_DoOneMessage(DDE_WIN2PROC(msg->hwnd), DDE_MSG_SIZE,
 345                              &msg_dat.dat);
 346   }
 347 }
 348
 349 BOOL DDE_SendMessage( MSG *msg)
 350 {
 351   return DDE_DoMessage(msg, DDE_SEND);
 352 }
 353
 354 BOOL DDE_PostMessage( MSG *msg)
 355 {
 356   return DDE_DoMessage(msg, DDE_POST);
 357 }
 358
 359
 360 void dde_proc_send_ack(HWND wnd, BOOL val) {
 361    int proc,msg;
 362
 363    static struct msgbuf msg_ack={DDE_ACK,{'0'}};
 364
 365    proc=DDE_WIN2PROC(wnd);
 366    msg=main_block->proc[proc].msg;
 367    dprintf_msg(stddeb,"DDE_GetRemoteMessage: sending ACK "
 368                "to wnd=%4x, proc=%d,msg=%d, pid=%d\n",wnd,proc,msg,
 369                main_block->proc[proc].pid
 370      );
 371
 372    msg_ack.mtext[0]=val;
 373    msgsnd (msg, &msg_ack, 1, 0);
 374    kill(main_block->proc[proc].pid, SIGUSR2);
 375 }
 376
 377 /* return true (non zero) if had a remote message */
 378 #undef DDE_GetRemoteMessage
 379
 380 int DDE_GetRemoteMessage()
 381 {
 382   static int nesting=0;            /* to avoid infinite recursion */
 383
 384   MSG *remote_message;
 385   int size;
 386   struct msg_dat msg_dat;
 387   BOOL was_sent;                   /* sent/received */
 388   BOOL passed;
 389   HWND hwnd;
 390   WND   *window;
 391
 392   if (curr_proc_idx==-1)           /* do we have DDE initialized ? */
 393      return 0;
 394
 395   if (nesting>10) {
 396      fflush(stdout);
 397      fprintf(stderr,"DDE_GetRemoteMessage: suspecting infinite recursion, exiting");
 398      return 0;
 399   }
 400
 401   remote_message=(void*)&msg_dat.dat.mtext;
 402
 403   /* test for SendMessage */
 404   size= msgrcv( main_block->proc[curr_proc_idx].msg , &msg_dat.dat,
 405                 DDE_MSG_SIZE, DDE_SEND, IPC_NOWAIT);
 406
 407   if (size==DDE_MSG_SIZE) {        /* is this a correct message (if any) ?*/
 408      was_sent=TRUE;
 409      dprintf_msg(stddeb,
 410                  "DDE:receive sent message. msg=%04x wPar=%04x"
 411                  " lPar=%08lx\n",
 412                  remote_message->message, remote_message->wParam,
 413                  remote_message->lParam);
 414   } else {
 415      size= msgrcv( main_block->proc[curr_proc_idx].msg , &msg_dat.dat,
 416                    DDE_MSG_SIZE, DDE_POST, IPC_NOWAIT);
 417
 418      if (size==DDE_MSG_SIZE) {     /* is this a correct message (if any) ?*/
 419         was_sent=FALSE;
 420         dprintf_msg(stddeb,
 421                     "DDE:receive posted message. "
 422                     "msg=%04x wPar=%04x lPar=%08lx\n",
 423                     remote_message->message, remote_message->wParam,
 424                     remote_message->lParam);
 425      }
 426      else
 427         return 0;                  /* no DDE message found */
 428   }
 429
 430   /* At this point we are sure that there is a DDE message,
 431    * was_sent is TRUE is the message was sent, and false if it was posted
 432    */
 433
 434   nesting++;
 435
 436   if (debugging_dde) {
 437      char *title;
 438      if (was_sent)
 439         title="receive sent dde:";
 440      else
 441         title="receive posted dde:";
 442      print_dde_message(title, remote_message);
 443   }
 444
 445   if (remote_message->hwnd != (HWND) -1 ) {
 446     HWND dde_window= DDE_WIN_INFO(remote_message->hwnd).wnd;
 447      /* we should know exactly where to send the message (locally)*/
 448      if (was_sent) {
 449         dprintf_dde(stddeb,
 450                     "SendMessage(wnd=0x%04x, msg=0x%04x, wPar=0x%04x,"
 451                     "lPar=0x%08x\n",
 452                     dde_window, remote_message->message,
 453                     remote_message->wParam, (int)remote_message->lParam);
 454
 455         /* execute the recieved message */
 456         passed= SendMessage(dde_window, remote_message->message,
 457                             remote_message->wParam, remote_message->lParam);
 458
 459         /* Tell the sended, that the message is here */
 460         dde_proc_send_ack(remote_message->wParam, passed);
 461      }
 462      else {
 463         passed= PostMessage(dde_window, remote_message->message,
 464                             remote_message->wParam, remote_message->lParam);
 465         if (passed == FALSE) {
 466            /* Tell the sender, that the message is here, and failed */
 467             dde_proc_send_ack(remote_message->wParam, FALSE);
 468         }
 469         else {
 470            /* ack will be sent later, at the first peek/get message  */
 471            dde_proc_add_fifo(remote_message->wParam);
 472         }
 473      }
 474      nesting--;
 475      return 1;
 476   }
 477
 478   /* iterate through all the windows */
 479   for (hwnd = GetTopWindow(GetDesktopWindow());
 480        hwnd && (window = WIN_FindWndPtr(hwnd))!=NULL ;
 481        hwnd = window->hwndNext) {
 482      if (window->dwStyle & WS_POPUP || window->dwStyle & WS_CAPTION) {
 483         if (was_sent)
 484            SendMessage( hwnd, remote_message->message,
 485                         remote_message->wParam, remote_message->lParam );
 486         else
 487            PostMessage( hwnd, remote_message->message,
 488                      remote_message->wParam, remote_message->lParam );
 489      } /* if */
 490   } /* for */
 491
 492   /* replay with DDE_ACK after broadcasting in DDE_GetRemoteMessage */
 493   dde_proc_send_ack(remote_message->wParam, TRUE);
 494
 495   nesting--;
 496   return 1;
 497 }
 498
 499 int dde_reschedule()
 500 {
 501     int ack_wnd;
 502
 503     ack_wnd= dde_proc_shift_fifo();
 504     if (ack_wnd != -1) {
 505         dde_proc_send_ack(ack_wnd, TRUE);
 506         usleep(10000);          /* force unix task switch */
 507         return 1;
 508     }
 509     return 0;
 510 }
 511 void dde_msg_setup(int *msg_ptr)
 512 {
 513   *msg_ptr= msgget (IPC_PRIVATE, IPC_CREAT | 0700);
 514   if (*msg_ptr==-1)
 515      perror("dde_msg_setup fails to get message queue");
 516 }
 517
 518 /* do we have dde handling in the window ?
 519  * If we have, atom usage will make this instance of wine set up
 520  * it's IPC stuff.
 521  */
 522 void DDE_TestDDE(HWND hwnd)
 523 {
 524
 525   if (main_block != NULL)
 526      return;
 527   dprintf_msg(stddeb,"DDE_TestDDE(0x%04x)\n", hwnd);
 528   if (hwnd==0)
 529       hwnd=-1;
 530   /* just send a message to see how things are going */
 531   SendMessage( hwnd, WM_DDE_INITIATE, 0, 0);
 532 }
 533
 534 void dde_proc_delete(int proc_idx)
 535 {
 536   dde_proc_done(&main_block->proc[proc_idx]);
 537 }
 538 void stop_wait(int a)
 539 {
 540
 541   had_SIGUSR2=1;
 542   switch(stop_wait_op) {
 543     case STOP_WAIT_ACK:
 544       siglongjmp(env_get_ack,1);
 545       break;  /* never reached */
 546     case STOP_WAIT_X:
 547       siglongjmp(env_wait_x,1);
 548       break;  /* never reached */
 549     case CONT:
 550       /* do nothing */
 551   }
 552 }
 553
 554 static void print_dde_message(char *desc, MSG *msg)
 555 {
 556     extern const char *MessageTypeNames[];
 557     extern int debug_last_handle_size;
 558     WORD wStatus,hWord;
 559     void *ptr;
 560     DDEACK *ddeack;
 561     DDEADVISE *ddeadvise;
 562     DDEDATA *ddedata;
 563     DDEPOKE *ddepoke;
 564
 565     if (is_dde_handle(msg->lParam & 0xffff) )
 566         ptr=DDE_AttachHandle(msg->lParam&0xffff, NULL);
 567     else
 568         ptr =NULL;
 569     wStatus=LOWORD(msg->lParam);
 570     hWord=HIWORD(msg->lParam);
 571
 572     fprintf(stddeb,"%s", desc);
 573     fprintf(stddeb,"%04x %04x==%s %04x %08lx ",
 574             msg->hwnd, msg->message,MessageTypeNames[msg->message],
 575             msg->wParam, msg->lParam);
 576     switch(msg->message) {
 577       case WM_DDE_INITIATE:
 578       case WM_DDE_REQUEST:
 579       case WM_DDE_EXECUTE:
 580       case WM_DDE_TERMINATE:
 581         /* nothing to do */
 582         break;
 583       case WM_DDE_ADVISE:
 584         /* DDEADVISE: hOptions in WM_DDE_ADVISE message */
 585         if (ptr) {
 586            ddeadvise=ptr;
 587            fprintf(stddeb,"fDeferUpd=%d,fAckReq=%d,cfFormat=0x%x",
 588                    ddeadvise->fDeferUpd, ddeadvise->fAckReq,
 589                    ddeadvise->cfFormat);
 590         } else
 591            fprintf(stddeb,"NO-DATA");
 592         fprintf(stddeb," atom=0x%x",hWord);
 593         break;
 594
 595       case WM_DDE_UNADVISE:
 596         fprintf(stddeb,"format=0x%x, atom=0x%x",wStatus,hWord);
 597         break;
 598       case WM_DDE_ACK:
 599         ddeack=(DDEACK*)&wStatus;
 600         fprintf(stddeb,"bAppReturnCode=%d,fBusy=%d,fAck=%d",
 601                 ddeack->bAppReturnCode, ddeack->fBusy, ddeack->fAck);
 602         if (ddeack->fAck)
 603            fprintf(stddeb,"(True)");
 604         else
 605            fprintf(stddeb,"(False)");
 606         break;
 607
 608       case WM_DDE_DATA:
 609         if (ptr) {
 610            ddedata=ptr;
 611            fprintf(stddeb,"fResponse=%d,fRelease=%d,"
 612                    "fAckReq=%d,cfFormat=0x%x,value=\"%.*s\"",
 613                    ddedata->fResponse, ddedata->fRelease,
 614                    ddedata->fAckReq, ddedata->cfFormat,
 615                    debug_last_handle_size- (int)sizeof(*ddedata)+1,
 616                    ddedata->Value);
 617         } else
 618            fprintf(stddeb,"NO-DATA");
 619         fprintf(stddeb," atom=0x%04x",hWord);
 620         break;
 621
 622       case WM_DDE_POKE:
 623         if (ptr) {
 624            ddepoke=ptr;
 625            fprintf(stddeb,"fRelease=%d,cfFormat=0x%x,value[0]='%c'",
 626                    ddepoke->fRelease, ddepoke->cfFormat, ddepoke->Value[0]);
 627         } else
 628            fprintf(stddeb,"NO-DATA");
 629         fprintf(stddeb," atom=0x%04x",hWord);
 630         break;
 631     }
 632     fprintf(stddeb,"\n");
 633 }
 634
 635 void dde_proc_done(dde_proc proc)
 636 {
 637   if (proc->msg != -1)
 638      msgctl(proc->msg, IPC_RMID, NULL);
 639   proc->msg=-1;
 640   proc->pid=-1;
 641   shm_delete_chain(&proc->shmid);
 642   shm_sem_done(&proc->sem);
 643 }
 644
 645 /* delete entry, if old junk */
 646 void dde_proc_refresh(dde_proc proc)
 647 {
 648   if (proc->pid == -1)
 649      return;
 650
 651   if (kill(proc->pid, 0) != -1)
 652      return;
 653
 654   /* get here if entry non empty, and the process does not exist */
 655   dde_proc_done(proc);
 656 }
 657
 658 void dde_wnd_setup()
 659 {
 660   int i;
 661
 662   for (i=0 ; i < DDE_WINDOWS ; i++)
 663     main_block->windows[i].proc_idx = FREE_WND;
 664 }
 665
 666 static BOOL DDE_ProcHasWindows(int proc_idx)
 667 {
 668   WND_DATA *tested;
 669   int i;
 670
 671   for ( i=0 ; i < DDE_WINDOWS ; i++) {
 672     tested= &main_block->windows[ i ];
 673
 674     if (tested->proc_idx == proc_idx)
 675       return TRUE;
 676   }
 677   return FALSE;
 678 }
 679 /* Look for hwnd in the hash table of DDE windows,
 680  * Delete it from there. If there are no more windows for this
 681  * process, remove the process from the DDE data-structure.
 682  * If there are no more processes - delete the whole DDE struff.
 683  *
 684  * This is inefficient, but who cares for the efficiency of this rare
 685  * operation...
 686  */
 687 void DDE_DestroyWindow(HWND hwnd)
 688 {
 689   int dde_wnd_idx;
 690   WND_DATA *tested;
 691   int i;
 692
 693   if (main_block == NULL)
 694     return;
 695
 696   dde_wnd_idx= hwnd % DDE_WINDOWS;
 697
 698   for ( i=0 ; i < DDE_WINDOWS ; i++, dde_wnd_idx++) {
 699     if (dde_wnd_idx >= DDE_WINDOWS)
 700       dde_wnd_idx -= DDE_WINDOWS; /* wrap-around */
 701
 702     tested= &main_block->windows[ dde_wnd_idx ];
 703     if (tested->proc_idx == FREE_WND)
 704       return;                   /* No window will get deleted here */
 705
 706     if (tested->wnd == hwnd && tested->proc_idx == curr_proc_idx) {
 707       dde_reschedule();
 708       tested->proc_idx= DELETED_WND;
 709       if (DDE_ProcHasWindows( curr_proc_idx ))
 710         return;
 711       while (dde_reschedule())  /* make sure there are no other */
 712                                 /* processes waiting for acknowledgment */
 713         ;
 714       dde_proc_delete( curr_proc_idx );
 715       if (DDE_no_of_attached() == 1)
 716         shm_delete_all(-1);
 717       else {
 718         shmdt( (void *) main_block);
 719         main_block= NULL;
 720       }
 721       return;
 722     }
 723   }
 724 }
 725
 726 #endif  /* CONFIG_IPC */