1    :  // Copyright 2012 Google Inc.
   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    :  // The runtime portion of a basic-block entry counting agent. This is
  16    :  // responsible for initializing the RPC connection and per-thread entry-count
  17    :  // buffer on demand as necessary as well as saturation incrementing the
  18    :  // appropriate counter when requested.
  19    :  //
  20    :  // The instrumenter can be used to inject a run-time dependency on this
  21    :  // library as well as to add the appropriate entry-hook code.
  22    :  
  23    :  #ifndef SYZYGY_AGENT_BASIC_BLOCK_ENTRY_BASIC_BLOCK_ENTRY_H_
  24    :  #define SYZYGY_AGENT_BASIC_BLOCK_ENTRY_BASIC_BLOCK_ENTRY_H_
  25    :  
  26    :  #include <windows.h>
  27    :  #include <winnt.h>
  28    :  #include <vector>
  29    :  
  30    :  #include "base/lazy_instance.h"
  31    :  #include "base/win/pe_image.h"
  32    :  #include "syzygy/agent/common/thread_state.h"
  33    :  #include "syzygy/common/basic_block_frequency_data.h"
  34    :  #include "syzygy/trace/client/rpc_session.h"
  35    :  
  36    :  // Instrumentation stub to handle entry to a basic-block.
  37  m :  extern "C" void _cdecl _basic_block_enter();
  38    :  
  39    :  // Instrumentation stub to handle the invocation of a DllMain-like entry point.
  40  m :  extern "C" void _cdecl _indirect_penter_dllmain();
  41    :  
  42  m :  namespace agent {
  43  m :  namespace basic_block_entry {
  44    :  
  45    :  // The basic-block entry counting agent.
  46    :  // @note: There's a single instance of this class.
  47  m :  class BasicBlockEntry {
  48  m :   public:
  49    :    // This structure describes the contents of the stack above a call to
  50    :    // BasicBlockEntry::BasicBlockEntryHook. A pointer to this structure will
  51    :    // be given to the BasicBlockEntryHook by _basic_block_enter.
  52  m :    struct BasicBlockEntryFrame;
  53    :  
  54    :    // This structure describes the contents of the stack above a call to
  55    :    // BasicBlockEntry::DllMainEntryHook(). A pointer to this structure will
  56    :    // be given to the BasicBlockEntryHook by _indirect_penter_dllmain.
  57  m :    struct DllMainEntryFrame;
  58    :  
  59    :    // Retrieves the coverage singleton instance.
  60  m :    static BasicBlockEntry* Instance();
  61    :  
  62    :    // Called from _basic_block_enter().
  63  m :    static void WINAPI BasicBlockEntryHook(BasicBlockEntryFrame* entry_frame);
  64    :  
  65    :    // Called from _indirect_penter_dllmain.
  66  m :    static void WINAPI DllMainEntryHook(DllMainEntryFrame* entry_frame);
  67    :  
  68  m :   protected:
  69    :    // This class defines the per-thread-per-instrumented-module state managed
  70    :    // by this agent.
  71  m :    class ThreadState;
  72  m :    friend class ThreadState;
  73    :  
  74    :    // Make sure the LazyInstance can be created.
  75  m :    friend struct base::DefaultLazyInstanceTraits<BasicBlockEntry>;
  76    :  
  77  m :    BasicBlockEntry();
  78  m :    ~BasicBlockEntry();
  79    :  
  80    :    // Handles DLL_PROCESS_ATTACH messages received by DllMainEntryHook().
  81  m :    void OnProcessAttach(DllMainEntryFrame* entry_frame);
  82    :  
  83    :    // Handles DLL_THREAD_DETACH and DLL_PROCESS_DETACH messages received by
  84    :    // DllMainEntryHook().
  85  m :    void OnThreadDetach(DllMainEntryFrame* entry_frame);
  86    :  
  87    :    // Registers the module containing @p addr with the call_trace_service.
  88  m :    void RegisterModule(const void* addr);
  89    :  
  90    :    // Create the local thread state for the current thread. This should only
  91    :    // be called if the local thread state has not already been created.
  92  m :    ThreadState* CreateThreadState(BasicBlockEntryFrame* entry_frame);
  93    :  
  94    :    // The RPC session we're logging to/through.
  95  m :    trace::client::RpcSession session_;
  96    :  
  97    :    // A helper to manage the life-cycle of the ThreadState instances allocated
  98    :    // by this agent.
  99  m :    agent::common::ThreadStateManager thread_state_manager_;
 100  m :  };
 101    :  
 102  m :  }  // namespace coverage
 103  m :  }  // namespace agent
 104    :  
 105    :  #endif  // SYZYGY_AGENT_BASIC_BLOCK_ENTRY_BASIC_BLOCK_ENTRY_H_