1    :  // Copyright 2013 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  //
  15    :  // Implementation of the jump table entry count agent library.
  16    :  
  17    :  #include "syzygy/agent/jump_table_count/jump_table_count.h"
  18    :  
  19    :  #include "base/at_exit.h"
  20    :  #include "base/logging.h"
  21    :  
  22  m :  extern "C" void __declspec(naked) _jump_table_case_counter() {
  23  m :    __asm {
  24    :      // This is expected to be called via instrumentation that looks like:
  25    :      //    push case_id
  26    :      //    call [_jump_table_case_counter]
  27    :      //
  28    :      // Stack: ... case_id, ret_addr.
  29    :  
  30    :      // TODO(sebmarchand): Implement this function.
  31  m :      ret 4
  32  m :    }
  33  m :  }
  34    :  
  35  m :  extern "C" void __declspec(naked) _indirect_penter_dllmain() {
  36  m :    __asm {
  37    :      // TODO(sebmarchand): Implement this function.
  38  m :      ret 4
  39  m :    }
  40  m :  }
  41    :  
  42  m :  BOOL WINAPI DllMain(HMODULE instance, DWORD reason, LPVOID reserved) {
  43    :    // Our AtExit manager required by base.
  44  m :    static base::AtExitManager* at_exit = NULL;
  45    :  
  46  m :    switch (reason) {
  47  m :      case DLL_PROCESS_ATTACH:
  48  m :        DCHECK(at_exit == NULL);
  49  m :        at_exit = new base::AtExitManager();
  50    :  
  51  m :        LOG(INFO) << "Initialized jump table entry count agent library.";
  52  m :        break;
  53    :  
  54  m :      case DLL_THREAD_ATTACH:
  55  m :        break;
  56    :  
  57  m :      case DLL_THREAD_DETACH:
  58  m :        break;
  59    :  
  60  m :      case DLL_PROCESS_DETACH:
  61  m :        DCHECK(at_exit != NULL);
  62  m :        delete at_exit;
  63  m :        at_exit = NULL;
  64  m :        break;
  65    :  
  66  m :      default:
  67  m :        NOTREACHED();
  68  m :        break;
  69  m :    }
  70    :  
  71  m :    return TRUE;
  72  m :  }