win: support x64 reading x86 (wow64)

snapshot/win/process_reader_win.h

 // Copyright 2015 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 #ifndef CRASHPAD_SNAPSHOT_WIN_PROCESS_READER_WIN_H_
 #define CRASHPAD_SNAPSHOT_WIN_PROCESS_READER_WIN_H_
 
 #include <sys/time.h>
 #include <windows.h>
 
 #include <vector>
 
+#include "build/build_config.h"
 #include "util/misc/initialization_state_dcheck.h"
 #include "util/win/address_types.h"
 #include "util/win/process_info.h"
 
 namespace crashpad {
 
 //! \brief State of process being read by ProcessReaderWin.
 enum class ProcessSuspensionState : bool {
   //! \brief The process has not been suspended.
   kRunning,
 
   //! \brief The process is suspended.
   kSuspended,
 };
 
 //! \brief Accesses information about another process, identified by a `HANDLE`.
 class ProcessReaderWin {
  public:
   //! \brief Contains information about a thread that belongs to a process.
   struct Thread {
     Thread();
     ~Thread() {}
 
-    CONTEXT context;
+    union {
+      CONTEXT native;
+#if defined(ARCH_CPU_64_BITS)
+      WOW64_CONTEXT wow64;
+#endif;
+    } context;
     uint64_t id;
     WinVMAddress teb;
     WinVMAddress stack_region_address;
     WinVMSize stack_region_size;
     uint32_t suspend_count;
     uint32_t priority_class;
     uint32_t priority;
   };
 
   ProcessReaderWin();
@@ skipping 44 matching lines @@
   //! \return The threads that are in the process. The first element (at index
   //!     `0`) corresponds to the main thread.
   const std::vector<Thread>& Threads();
 
   //! \return The modules loaded in the process. The first element (at index
   //!     `0`) corresponds to the main executable.
   const std::vector<ProcessInfo::Module>& Modules();
 
  private:
   template <class Traits>
-  void ReadThreadData();
+  void ReadThreadData(bool is_64_reading_32);
 
   HANDLE process_;
   ProcessInfo process_info_;
   std::vector<Thread> threads_;
   std::vector<ProcessInfo::Module> modules_;
   ProcessSuspensionState suspension_state_;
   bool initialized_threads_;
   InitializationStateDcheck initialized_;
 
   DISALLOW_COPY_AND_ASSIGN(ProcessReaderWin);
 };
 
 }  // namespace crashpad
 
 #endif  // CRASHPAD_SNAPSHOT_WIN_PROCESS_READER_WIN_H_