lib/c++/orb.cc

   1 #include <System.h>
   2 #include <util/radix.h>
   3
   4 namespace System {
   5 namespace RunTime {
   6         using namespace ::System::Exceptions::Std;
   7
   8         // This function could be made to do a binary search if we can
   9         // manage to somehow sort the IFaceTables...
  10         uintptr_t downcast(::System::_i_Object *obj, const GUID *new_guid)
  11         {
  12                 if (!obj)
  13                         return 0;
  14
  15                 void unsupported_long_size();
  16
  17                 if (sizeof(long) != 4 && sizeof(long) != 8)
  18                         unsupported_long_size();
  19
  20                 IFaceTable *tbl = obj->info->concrete_IFaceTable;
  21                 unsigned long new_guid_first = new_guid->l[0];
  22
  23                 // This doesn't use guids_equal(), as that would eliminate the
  24                 // ability to cache the first word of new_guid.  The compiler
  25                 // *might* do it anyway, but this code was written before
  26                 // guids_equal existed, and I don't want to risk removing an
  27                 // optimization by changing it now without testing how GCC
  28                 // behaves.
  29
  30                 while (true) {
  31                         if (tbl->info->guid->l[0] == new_guid_first &&
  32                             tbl->info->guid->l[1] == new_guid->l[1] &&
  33                             (sizeof(long) == 8 ||
  34                              (tbl->info->guid->l[2] == new_guid->l[2] &&
  35                               tbl->info->guid->l[3] == new_guid->l[3])))
  36                                 break;
  37
  38                         tbl++;
  39                         if (__builtin_expect(!tbl->info->guid->l[0], 0))
  40                                 return 0;
  41                 }
  42
  43                 uintptr_t ptr = reinterpret_cast<uintptr_t>(obj);
  44
  45                 ptr += obj->info->concrete;
  46                 ptr += tbl->offset;
  47
  48                 return ptr;
  49         };
  50
  51         namespace Priv {
  52                 typedef void (*MethodEntry)(ParamInfoBlock *pib);
  53
  54                 struct Object {
  55                         MethodEntry entry;
  56                         void *ptr; // pointer to the class interface
  57                 };
  58
  59                 typedef ::Util::RadixTree<Object, ID, 6> ObjTable;
  60                 ObjTable objtable;
  61
  62                 unsigned long get_pc()
  63                 {
  64                         return reinterpret_cast<unsigned long>(__builtin_return_address(0));
  65                 }
  66
  67                 void exception_to_array(::System::VStruct *ex, Array<uint8_t> *ar)
  68                 {
  69                         // FIXME: marshall struct
  70                 }
  71
  72                 void handle_message(ParamInfoBlock *pib)
  73                 {
  74                         Message *msg = reinterpret_cast<Message *>(pib->segments[0].ptr);
  75
  76                         switch (msg->seg0.opcode) {
  77                                 case Segment0::InvokeMethod: {
  78                                         if (pib->segments[0].len < sizeof(InvokeMethod))
  79                                                 throw_idl(ShortMessage, 0, pib->segments[0].len,
  80                                                           sizeof(InvokeMethod));
  81
  82 //                                      ID obj = pib->objlist[0];
  83                                         break;
  84                                 }
  85
  86                                 default:
  87                                         throw_idl(InvalidOpcode, msg->seg0.opcode);
  88                         }
  89                 }
  90         }
  91 }}
  92
  93 extern "C" void abort();
  94
  95 extern "C" void handle_message(::System::RunTime::ParamInfoBlock *pib,
  96                                ::System::RunTime::Array<uint8_t> *ex_arr)
  97 {
  98         try {
  99                 ::System::RunTime::Priv::handle_message(pib);
 100         }
 101
 102         catch (::System::Exceptions::Exception &ex) {
 103                 ::System::RunTime::Priv::exception_to_array(&ex, ex_arr);
 104         }
 105
 106         catch (...) {
 107                 abort();
 108         }
 109 }