michael@0: // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include <windows.h>
michael@0: 
michael@0: #include "base/debug_on_start.h"
michael@0: 
michael@0: #include "base/base_switches.h"
michael@0: #include "base/basictypes.h"
michael@0: #include "base/debug_util.h"
michael@0: 
michael@0: // Minimalist implementation to try to find a command line argument. We can use
michael@0: // kernel32 exported functions but not the CRT functions because we're too early
michael@0: // in the process startup.
michael@0: // The code is not that bright and will find things like ---argument or
michael@0: // /-/argument.
michael@0: // Note: command_line is non-destructively modified.
michael@0: bool DebugOnStart::FindArgument(wchar_t* command_line, const wchar_t* argument)
michael@0: {
michael@0:   int argument_len = lstrlen(argument);
michael@0:   int command_line_len = lstrlen(command_line);
michael@0:   while (command_line_len > argument_len) {
michael@0:     wchar_t first_char = command_line[0];
michael@0:     wchar_t last_char = command_line[argument_len+1];
michael@0:     // Try to find an argument.
michael@0:     if ((first_char == L'-' || first_char == L'/') &&
michael@0:         (last_char == L' ' || last_char == 0 || last_char == L'=')) {
michael@0:       command_line[argument_len+1] = 0;
michael@0:       // Skip the - or /
michael@0:       if (lstrcmpi(command_line+1, argument) == 0) {
michael@0:         // Found it.
michael@0:         command_line[argument_len+1] = last_char;
michael@0:         return true;
michael@0:       }
michael@0:       // Fix back.
michael@0:       command_line[argument_len+1] = last_char;
michael@0:     }
michael@0:     // Continue searching.
michael@0:     ++command_line;
michael@0:     --command_line_len;
michael@0:   }
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: // static
michael@0: int __cdecl DebugOnStart::Init() {
michael@0:   // Try to find the argument.
michael@0:   if (FindArgument(GetCommandLine(), switches::kDebugOnStart)) {
michael@0:     // We can do 2 things here:
michael@0:     // - Ask for a debugger to attach to us. This involve reading the registry
michael@0:     //   key and creating the process.
michael@0:     // - Do a int3.
michael@0: 
michael@0:     // It will fails if we run in a sandbox. That is expected.
michael@0:     DebugUtil::SpawnDebuggerOnProcess(GetCurrentProcessId());
michael@0: 
michael@0:     // Wait for a debugger to come take us.
michael@0:     DebugUtil::WaitForDebugger(60, false);
michael@0:   } else if (FindArgument(GetCommandLine(), switches::kWaitForDebugger)) {
michael@0:     // Wait for a debugger to come take us.
michael@0:     DebugUtil::WaitForDebugger(60, true);
michael@0:   }
michael@0:   return 0;
michael@0: }