TAO/tao/RTCORBA/Linear_Priority_Mapping.cpp

   1 #include "tao/orbconf.h"
   2
   3 #if defined (TAO_HAS_CORBA_MESSAGING) && TAO_HAS_CORBA_MESSAGING != 0
   4
   5 #include "tao/RTCORBA/Linear_Priority_Mapping.h"
   6 #include "tao/debug.h"
   7 #include "ace/Sched_Params.h"
   8 #include "ace/Log_Msg.h"
   9
  10 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
  11
  12 TAO_Linear_Priority_Mapping::TAO_Linear_Priority_Mapping (long policy)
  13   : policy_ (policy)
  14   , min_ (ACE_Sched_Params::priority_min (this->policy_))
  15   , max_ (ACE_Sched_Params::priority_max (this->policy_))
  16 {
  17 }
  18
  19 TAO_Linear_Priority_Mapping::~TAO_Linear_Priority_Mapping ()
  20 {
  21 }
  22
  23 CORBA::Boolean
  24 TAO_Linear_Priority_Mapping::to_native (
  25   RTCORBA::Priority corba_priority,
  26   RTCORBA::NativePriority &native_priority)
  27 {
  28   if (corba_priority < RTCORBA::minPriority
  29            // The line below will always be false unless the value of
  30            // RTCORBA::maxPriority, which is now assigned the value of
  31            // 32767, is changed in RTCORBA.pidl.
  32 //      || corba_priority > RTCORBA::maxPriority
  33      )
  34     {
  35       return 0;
  36     }
  37
  38 #if defined (ACE_WIN32)
  39   // Count up the number of distinct native priorities on current
  40   // platform.
  41   int n;
  42   int current_priority = this->min_;
  43   for (n = 1; current_priority != this->max_; ++n)
  44     {
  45       current_priority =
  46         ACE_Sched_Params::next_priority (this->policy_,
  47                                          current_priority);
  48     }
  49   int native_priority_index =
  50     1
  51     + ((n - 1)
  52        * (corba_priority - RTCORBA::minPriority)
  53        / (RTCORBA::maxPriority - RTCORBA::minPriority));
  54
  55   // Now, find the value corresponding to this index.
  56   native_priority = static_cast<RTCORBA::NativePriority> (this->min_);
  57   for (int i = 2; i <= native_priority_index; ++i)
  58     {
  59       native_priority = static_cast<RTCORBA::NativePriority>
  60         (ACE_Sched_Params::next_priority (this->policy_, native_priority));
  61     }
  62   return 1;
  63
  64 #else
  65
  66   native_priority =
  67     this->min_
  68     + ((this->max_ - this->min_)
  69        * (corba_priority - RTCORBA::minPriority)
  70        / (RTCORBA::maxPriority - RTCORBA::minPriority));
  71
  72   return 1;
  73
  74 #endif /* ACE_WIN32 */
  75 }
  76
  77 CORBA::Boolean
  78 TAO_Linear_Priority_Mapping::to_CORBA (RTCORBA::NativePriority native_priority,
  79                                        RTCORBA::Priority &corba_priority)
  80 {
  81 #if defined (ACE_WIN32)
  82
  83   // Iterate over native priorities in order to 1) make sure
  84   // <native_priority> argument contains a valid value, 2) count its
  85   // index among all valid native pr. values, 3) get the total number
  86   // of native priority values for the current platform.
  87
  88   int total;
  89   int native_priority_index = 0;
  90   int current_priority = this->min_;
  91   for (total = 1; ; ++total)
  92     {
  93       if (native_priority == current_priority)
  94         native_priority_index = total;
  95
  96       if (current_priority == this->max_)
  97         break;
  98
  99       current_priority =
 100         ACE_Sched_Params::next_priority (this->policy_,
 101                                          current_priority);
 102     }
 103
 104   if (native_priority_index == 0)
 105     return 0;
 106
 107   int delta = total - 1;
 108   if (delta != 0)
 109     {
 110       int numerator = (RTCORBA::maxPriority - RTCORBA::minPriority)
 111                             * (native_priority_index - 1);
 112
 113       div_t corba_offset = div (numerator, delta);
 114
 115       int rounding = 0;
 116
 117       if (corba_offset.rem)
 118         {
 119           rounding = ((numerator < 0 && delta < 0) ||
 120                       (numerator >= 0 && delta >= 0) ? 1 : -1);
 121         }
 122
 123       corba_priority = static_cast<RTCORBA::Priority>
 124         (RTCORBA::minPriority + corba_offset.quot + rounding);
 125     }
 126   else
 127     {
 128       // There is only one native priority.
 129       corba_priority = RTCORBA::minPriority;
 130     }
 131
 132   return 1;
 133
 134 #else
 135
 136   if ((this->min_ < this->max_
 137        && (native_priority < this->min_
 138            || native_priority > this->max_))
 139       || (this->min_ > this->max_
 140           && (native_priority < this->max_
 141               || native_priority > this->min_)))
 142     {
 143         TAOLIB_DEBUG ((LM_DEBUG,
 144                     "TAO (%P|%t) - Linear_Priority_Mapping::to_CORBA: "
 145                     " priority %d out of range [%d,%d]\n",
 146                     native_priority, this->min_, this->max_));
 147       return 0;
 148     }
 149
 150   int delta = this->max_ - this->min_;
 151   if (delta != 0)
 152     {
 153       int numerator = (RTCORBA::maxPriority - RTCORBA::minPriority)
 154                             * (native_priority - this->min_);
 155
 156       div_t corba_offset = div (numerator, delta);
 157
 158       int rounding = 0;
 159
 160       if (corba_offset.rem)
 161         {
 162           rounding = ((numerator < 0 && delta < 0) ||
 163                       (numerator >= 0 && delta >= 0) ? 1 : -1);
 164         }
 165
 166       corba_priority =
 167         RTCORBA::minPriority + corba_offset.quot + rounding;
 168     }
 169   else
 170     {
 171       // There is only one native priority.
 172       if (native_priority != this->min_)
 173         return 0;
 174       corba_priority = RTCORBA::minPriority;
 175     }
 176
 177   return 1;
 178
 179 #endif /* ACE_WIN32 */
 180 }
 181
 182 TAO_END_VERSIONED_NAMESPACE_DECL
 183
 184 #endif /* TAO_HAS_CORBA_MESSAGING && TAO_HAS_CORBA_MESSAGING != 0 */