usr/src/cmd/man/src/util/nsgmls.src/lib/DescriptorManager.cxx

   1 // Copyright (c) 1994 James Clark
   2 // See the file COPYING for copying permission.
   3 #pragma ident   "%Z%%M% %I%     %E% SMI"
   4
   5 #include "splib.h"
   6 #include "DescriptorManager.h"
   7 #include "ListIter.h"
   8
   9 #ifdef SP_NAMESPACE
  10 namespace SP_NAMESPACE {
  11 #endif
  12
  13 DescriptorUser::DescriptorUser(DescriptorManager *manager)
  14 : manager_(manager)
  15 {
  16   if (manager_)
  17     manager_->addUser(this);
  18 }
  19
  20 DescriptorUser::~DescriptorUser()
  21 {
  22   if (manager_)
  23     manager_->removeUser(this);
  24 }
  25
  26 void DescriptorUser::managerDeleted()
  27 {
  28   manager_ = 0;
  29 }
  30
  31 Boolean DescriptorUser::suspend()
  32 {
  33   return 0;
  34 }
  35
  36 void DescriptorUser::acquireD()
  37 {
  38   if (manager_)
  39     manager_->acquireD();
  40 }
  41
  42 void DescriptorUser::releaseD()
  43 {
  44   if (manager_)
  45     manager_->releaseD();
  46 }
  47
  48 DescriptorManager::DescriptorManager(int maxD)
  49 : maxD_(maxD), usedD_(0)
  50 {
  51 }
  52
  53 DescriptorManager::~DescriptorManager()
  54 {
  55   for (ListIter<DescriptorUser *> iter(users_);
  56        !iter.done();
  57        iter.next())
  58     iter.cur()->managerDeleted();
  59 }
  60
  61 void DescriptorManager::addUser(DescriptorUser *p)
  62 {
  63   users_.insert(p);
  64 }
  65
  66 void DescriptorManager::removeUser(DescriptorUser *p)
  67 {
  68   users_.remove(p);
  69 }
  70
  71 void DescriptorManager::acquireD()
  72 {
  73   if (usedD_ >= maxD_) {
  74     for (ListIter<DescriptorUser *> iter(users_);
  75          !iter.done();
  76          iter.next()) {
  77       if (iter.cur()->suspend())
  78         break;
  79     }
  80   }
  81   usedD_++;
  82 }
  83
  84 void DescriptorManager::releaseD()
  85 {
  86   usedD_--;
  87 }
  88
  89 #ifdef SP_NAMESPACE
  90 }
  91 #endif