src/WINNT/afsadmsvr/TaAfsAdmSvrCallback.cpp

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   5  * This software has been released under the terms of the IBM Public
   6  * License.  For details, see the LICENSE file in the top-level source
   7  * directory or online at http://www.openafs.org/dl/license10.html
   8  */
   9
  10 #include <winsock2.h>
  11 #include <ws2tcpip.h>
  12
  13 #include <afs/param.h>
  14 #include <afs/stds.h>
  15
  16 #include "TaAfsAdmSvrInternal.h"
  17
  18 /*
  19  * VARIABLES __________________________________________________________________
  20  *
  21  */
  22
  23 typedef struct
  24    {
  25    CALLBACKTYPE Type;
  26    BOOL fFinished;
  27    LPASACTION pAction;
  28    } CALLBACKDATA, *LPCALLBACKDATA;
  29
  30 static struct
  31    {
  32    HANDLE heCallback;
  33    LPHASHLIST pListCallbacks;
  34    BOOL fStopManagers;
  35    size_t cManagers;
  36    } l;
  37
  38
  39 /*
  40  * CALLBACKS __________________________________________________________________
  41  *
  42  */
  43
  44 void AfsAdmSvr_FreeCallbackData (LPCALLBACKDATA pData)
  45 {
  46    if (pData)
  47       {
  48       if (pData->pAction)
  49          Delete (pData->pAction);
  50       Delete (pData);
  51       }
  52 }
  53
  54
  55 void AfsAdmSvr_CallbackManager (void)
  56 {
  57    AfsAdmSvr_Enter();
  58    if ((++l.cManagers) == 1)
  59       {
  60       l.heCallback = CreateEvent (NULL, TRUE, FALSE, TEXT("AfsAdmSvr_CallbackManager Event"));
  61       l.pListCallbacks = New (HASHLIST);
  62       }
  63    AfsAdmSvr_Leave();
  64
  65    for (;;)
  66       {
  67       WaitForSingleObjectEx (l.heCallback, INFINITE, FALSE);
  68
  69       if (l.fStopManagers)
  70          break;
  71
  72       // We must ensure that we don't block the server's operations because
  73       // a callback doesn't go through; since other operations may need
  74       // access to the l.pListCallbacks structure in order to queue new
  75       // callbacks, we can't leave it locked by issuing callbacks while
  76       // enumerating it. Instead we'll copy the list into a local copy,
  77       // clear it, and enumerate that local copy--other threads can then
  78       // continue to add new requests to l.pListCallbacks.
  79       //
  80       AfsAdmSvr_Enter();
  81
  82       LPHASHLIST pList = New (HASHLIST);
  83       LPENUM pEnum;
  84       for (pEnum = l.pListCallbacks->FindFirst(); pEnum; pEnum = pEnum->FindNext())
  85          {
  86          LPCALLBACKDATA pData = (LPCALLBACKDATA)( pEnum->GetObject() );
  87          pList->Add (pData);
  88          l.pListCallbacks->Remove (pData);
  89          }
  90
  91       ResetEvent (l.heCallback);
  92       AfsAdmSvr_Leave();
  93
  94       // Now enumerate that copied list, and issue callbacks for each item.
  95       //
  96       for (pEnum = pList->FindFirst(); pEnum; pEnum = pEnum->FindNext())
  97          {
  98          LPCALLBACKDATA pData = (LPCALLBACKDATA)( pEnum->GetObject() );
  99
 100          try {
 101             switch (pData->Type)
 102                {
 103                case cbtACTION:
 104                   AfsAdmSvrCallback_Action (pData->pAction, pData->fFinished);
 105                   break;
 106                }
 107          } catch(...) {
 108             ;
 109          }
 110
 111          pList->Remove (pData);
 112          AfsAdmSvr_FreeCallbackData (pData);
 113          }
 114
 115       Delete (pList);
 116       }
 117
 118    AfsAdmSvr_Enter();
 119    if ((--l.cManagers) == 0)
 120       {
 121       Delete (l.pListCallbacks);
 122       l.pListCallbacks = NULL;
 123       CloseHandle (l.heCallback);
 124       l.heCallback = NULL;
 125       }
 126    AfsAdmSvr_Leave();
 127 }
 128
 129
 130 void AfsAdmSvr_PostCallback (CALLBACKTYPE Type, BOOL fFinished, LPASACTION pAction, DWORD dwRemoveMe)
 131 {
 132    AfsAdmSvr_Enter();
 133    if (l.pListCallbacks)
 134       {
 135       LPCALLBACKDATA pData = New (CALLBACKDATA);
 136       memset (pData, 0x00, sizeof(CALLBACKDATA));
 137       pData->Type = Type;
 138       pData->fFinished = fFinished;
 139       if (pAction)
 140          {
 141          pData->pAction = New (ASACTION);
 142          memcpy (pData->pAction, pAction, sizeof(ASACTION));
 143          }
 144
 145       l.pListCallbacks->Add (pData);
 146       SetEvent (l.heCallback);
 147       }
 148    AfsAdmSvr_Leave();
 149 }
 150
 151
 152 void AfsAdmSvr_PostCallback (CALLBACKTYPE Type, BOOL fFinished, LPASACTION pAction)
 153 {
 154    AfsAdmSvr_PostCallback (Type, fFinished, pAction, 0);
 155 }
 156
 157
 158 void AfsAdmSvr_StopCallbackManagers (void)
 159 {
 160    AfsAdmSvr_Enter();
 161    if (l.cManagers)
 162       {
 163       l.fStopManagers = TRUE;
 164       SetEvent (l.heCallback);
 165       }
 166    AfsAdmSvr_Leave();
 167 }
 168