Make debug_util cross platform, adding BeingDebugged and BreakDebugger. Linux

supported added, and Mac OSX left as a todo for the mac team.


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@785 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 127 insertions, 0 deletions

diff --git a/base/debug_util_win.cc b/base/debug_util_win.cc
new file mode 100644
index 0000000..0f67a16
--- /dev/null
+++ b/base/debug_util_win.cc
@@ -0,0 +1,127 @@
+// Copyright 2008, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <windows.h>
+
+#include "base/basictypes.h"
+#include "base/debug_util.h"
+
+namespace {
+
+// Minimalist key reader.
+// Note: Does not use the CRT.
+bool RegReadString(HKEY root, const wchar_t* subkey,
+                   const wchar_t* value_name, wchar_t* buffer, int* len) {
+  HKEY key = NULL;
+  DWORD res = RegOpenKeyEx(root, subkey, 0, KEY_READ, &key);
+  if (ERROR_SUCCESS != res || key == NULL)
+    return false;
+
+  DWORD type = 0;
+  DWORD buffer_size = *len * sizeof(wchar_t);
+  // We don't support REG_EXPAND_SZ.
+  res = RegQueryValueEx(key, value_name, NULL, &type,
+                        reinterpret_cast<BYTE*>(buffer), &buffer_size);
+  if (ERROR_SUCCESS == res && buffer_size != 0 && type == REG_SZ) {
+    // Make sure the buffer is NULL terminated.
+    buffer[*len - 1] = 0;
+    *len = lstrlen(buffer);
+    RegCloseKey(key);
+    return true;
+  }
+  RegCloseKey(key);
+  return false;
+}
+
+// Replaces each "%ld" in input per a value. Not efficient but it works.
+// Note: Does not use the CRT.
+bool StringReplace(const wchar_t* input, int value, wchar_t* output,
+                   int output_len) {
+  memset(output, 0, output_len*sizeof(wchar_t));
+  int input_len = lstrlen(input);
+
+  for (int i = 0; i < input_len; ++i) {
+    int current_output_len = lstrlen(output);
+
+    if (input[i] == L'%' && input[i + 1] == L'l' && input[i + 2] == L'd') {
+      // Make sure we have enough place left.
+      if ((current_output_len + 12) >= output_len)
+        return false;
+
+      // Cheap _itow().
+      wsprintf(output+current_output_len, L"%d", value);
+      i += 2;
+    } else {
+      if (current_output_len >= output_len)
+        return false;
+      output[current_output_len] = input[i];
+    }
+  }
+  return true;
+}
+
+}  // namespace
+
+// Note: Does not use the CRT.
+bool DebugUtil::SpawnDebuggerOnProcess(unsigned process_id) {
+  wchar_t reg_value[1026];
+  int len = arraysize(reg_value);
+  if (RegReadString(HKEY_LOCAL_MACHINE,
+      L"SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug",
+      L"Debugger", reg_value, &len)) {
+    wchar_t command_line[1026];
+    if (StringReplace(reg_value, process_id, command_line,
+                      arraysize(command_line))) {
+      // We don't mind if the debugger is present because it will simply fail
+      // to attach to this process.
+      STARTUPINFO startup_info = {0};
+      startup_info.cb = sizeof(startup_info);
+      PROCESS_INFORMATION process_info = {0};
+
+      if (CreateProcess(NULL, command_line, NULL, NULL, FALSE, 0, NULL, NULL,
+                        &startup_info, &process_info)) {
+        CloseHandle(process_info.hThread);
+        WaitForInputIdle(process_info.hProcess, 10000);
+        CloseHandle(process_info.hProcess);
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+// static
+bool DebugUtil::BeingDebugged() {
+  return ::IsDebuggerPresent() != 0;
+}
+
+// static
+void DebugUtil::BreakDebugger() {
+  __debugbreak();
+}