13f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use of this source code is governed by a BSD-style license that can be 3c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// found in the LICENSE file. 4c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 5c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Define the necessary code and global data to look for kDebugOnStart command 6c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// line argument. When the command line argument is detected, it invokes the 7c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// debugger, if no system-wide debugger is registered, a debug break is done. 8c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 93f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen#ifndef BASE_DEBUG_DEBUG_ON_START_WIN_H_ 103f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen#define BASE_DEBUG_DEBUG_ON_START_WIN_H_ 113345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#pragma once 12c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 13c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/basictypes.h" 143f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen#include "build/build_config.h" 15c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 163f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen// This only works on Windows. It's legal to include on other platforms, but 173f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen// will be a NOP. 18c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#if defined(OS_WIN) 19c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 20c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#ifndef DECLSPEC_SELECTANY 21c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#define DECLSPEC_SELECTANY __declspec(selectany) 22c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#endif 23c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 243f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsennamespace base { 253f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsennamespace debug { 263f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen 27ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen// There is no way for this code, as currently implemented, to work across DLLs. 28ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen// TODO(rvargas): It looks like we really don't use this code, at least not for 29ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen// Chrome. Figure out if it's really worth implementing something simpler. 30ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen#if !defined(BASE_DLL) 31ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen 32c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Debug on start functions and data. 33c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottclass DebugOnStart { 34c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott public: 35c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Expected function type in the .CRT$XI* section. 36c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Note: See VC\crt\src\internal.h for reference. 37c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott typedef int (__cdecl *PIFV)(void); 38c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 39c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Looks at the command line for kDebugOnStart argument. If found, it invokes 40c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // the debugger, if this fails, it crashes. 41c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott static int __cdecl Init(); 42c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 43c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Returns true if the 'argument' is present in the 'command_line'. It does 44c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // not use the CRT, only Kernel32 functions. 45c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott static bool FindArgument(wchar_t* command_line, const char* argument); 46c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott}; 47c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 48c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Set the function pointer to our function to look for a crash on start. The 49c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// XIB section is started pretty early in the program initialization so in 50c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// theory it should be called before any user created global variable 51c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// initialization code and CRT initialization code. 52c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Note: See VC\crt\src\defsects.inc and VC\crt\src\crt0.c for reference. 53c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#ifdef _WIN64 54c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 55c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// "Fix" the segment. On x64, the .CRT segment is merged into the .rdata segment 56c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// so it contains const data only. 57c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#pragma const_seg(push, ".CRT$XIB") 58c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Declare the pointer so the CRT will find it. 59c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottextern const DebugOnStart::PIFV debug_on_start; 60c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick ScottDECLSPEC_SELECTANY const DebugOnStart::PIFV debug_on_start = 61c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott &DebugOnStart::Init; 62c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Fix back the segment. 63c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#pragma const_seg(pop) 64c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 65c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#else // _WIN64 66c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 67c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// "Fix" the segment. On x86, the .CRT segment is merged into the .data segment 68c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// so it contains non-const data only. 69c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#pragma data_seg(push, ".CRT$XIB") 70c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Declare the pointer so the CRT will find it. 71c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick ScottDECLSPEC_SELECTANY DebugOnStart::PIFV debug_on_start = &DebugOnStart::Init; 72c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Fix back the segment. 73c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#pragma data_seg(pop) 74c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 75c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#endif // _WIN64 763f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen 77ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen#endif // defined(BASE_DLL) 78ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen 793f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen} // namespace debug 803f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen} // namespace base 813f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen 82c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#endif // defined(OS_WIN) 83c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 843f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen#endif // BASE_DEBUG_DEBUG_ON_START_WIN_H_ 85