win: Capture some memory pointed at by context

handler/win/crashy_test_program.cc

 // 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.
 
+#include <intrin.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <sys/types.h>
 #include <windows.h>
 #include <winternl.h>
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "client/crashpad_client.h"
 #include "util/win/critical_section_with_debug_info.h"
 #include "util/win/get_function.h"
 
 // ntstatus.h conflicts with windows.h so define this locally.
 #ifndef STATUS_NO_SUCH_FILE
 #define STATUS_NO_SUCH_FILE static_cast<NTSTATUS>(0xC000000F)
 #endif
 
 namespace crashpad {
 namespace {
 
 CRITICAL_SECTION g_test_critical_section;
 
+unsigned char g_test_memory[] = {
+  99, 98, 97, 96, 95, 94, 93, 92, 91, 90,
+  89, 88, 87, 86, 85, 84, 83, 82, 81, 80,
+};
+
 ULONG RtlNtStatusToDosError(NTSTATUS status) {
   static const auto rtl_nt_status_to_dos_error =
       GET_FUNCTION_REQUIRED(L"ntdll.dll", ::RtlNtStatusToDosError);
   return rtl_nt_status_to_dos_error(status);
 }
 
 void AllocateMemoryOfVariousProtections() {
   SYSTEM_INFO system_info;
   GetSystemInfo(&system_info);
 
@@ skipping 31 matching lines @@
     PCHECK(result) << "VirtualAlloc MEM_COMMIT " << i;
   }
 }
 
 void SomeCrashyFunction() {
   // SetLastError and NTSTATUS so that we have something to view in !gle in
   // windbg. RtlNtStatusToDosError() stores STATUS_NO_SUCH_FILE into the
   // LastStatusError of the TEB as a side-effect, and we'll be setting
   // ERROR_FILE_NOT_FOUND for GetLastError().
   SetLastError(RtlNtStatusToDosError(STATUS_NO_SUCH_FILE));
+
+  // Set a register to point at some memory we can test to confirm it makes it
+  // into the minidump. We use __movsb as a way to set SI/DI without needing an
+  // external .asm file.
+  __movsb(g_test_memory, g_test_memory, 0);
+
   volatile int* foo = reinterpret_cast<volatile int*>(7);
   *foo = 42;
 }
 
 int CrashyMain(int argc, wchar_t* argv[]) {
   CrashpadClient client;
 
   if (argc == 2) {
     if (!client.SetHandlerIPCPipe(argv[1])) {
       LOG(ERROR) << "SetHandler";
@@ skipping 31 matching lines @@
 
   return EXIT_SUCCESS;
 }
 
 }  // namespace
 }  // namespace crashpad
 
 int wmain(int argc, wchar_t* argv[]) {
   return crashpad::CrashyMain(argc, argv);
 }