Initial import of the Chrome Frame codebase. Integration in chrome.gyp coming...

chrome_frame/chrome_launcher_main.cc

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <windows.h>
+
+#include "chrome_frame/chrome_launcher.h"
+
+// We want to keep this EXE tiny, so we avoid all dependencies and link to no
+// libraries, and we do not use the C runtime.
+//
+// To catch errors in debug builds, we define an extremely simple assert macro.
+#ifndef NDEBUG
+#define CLM_ASSERT(x) do { if (!(x)) { ::DebugBreak(); } } while (false)
+#else
+#define CLM_ASSERT(x)
+#endif  // NDEBUG
+
+// In release builds, we skip the standard library completely to minimize
+// size.  This is more work in debug builds, and unnecessary, hence the
+// different signatures.
+#ifndef NDEBUG
+int APIENTRY wWinMain(HINSTANCE, HINSTANCE, wchar_t*, int) {
+#else
+extern "C" void __cdecl WinMainCRTStartup() {
+#endif  // NDEBUG
+  // This relies on the chrome_launcher.exe residing in the same directory
+  // as our DLL.  We build a full path to avoid loading it from any other
+  // directory in the DLL search path.
+  //
+  // The code is a bit verbose because we can't use the standard library.
+  const wchar_t kBaseName[] = L"npchrome_tab.dll";
+  wchar_t file_path[MAX_PATH + (sizeof(kBaseName) / sizeof(kBaseName[0])) + 1];
+  file_path[0] = L'\0';
+  ::GetModuleFileName(::GetModuleHandle(NULL), file_path, MAX_PATH);
+
+  // Find index of last slash, and null-terminate the string after it.
+  //
+  // Proof for security purposes, since we can't use the safe string
+  // manipulation functions from the runtime:
+  // - File_path is always null-terminated, by us initially and by 
+  //   ::GetModuleFileName if it puts anything into the buffer.
+  // - If there is no slash in the path then it's a relative path, not an
+  //   absolute one, and the code ends up creating a relative path to
+  //   npchrome_tab.dll.
+  // - It's safe to use lstrcatW since we know the maximum length of both
+  //   parts we are concatenating, and we know the buffer will fit them in
+  //   the worst case.
+  int slash_index = lstrlenW(file_path);
+  // Invariant: 0 <= slash_index < MAX_PATH
+  CLM_ASSERT(slash_index > 0);
+  while (slash_index > 0 && file_path[slash_index] != L'\\')
+    --slash_index;
+  // Invariant: 0 <= slash_index < MAX_PATH and it is either the index of 
+  // the last \ in the path, or 0.
+  if (slash_index != 0)
+    ++slash_index;  // don't remove the last '\'
+  file_path[slash_index] = L'\0';
+
+  lstrcatW(file_path, kBaseName);
+
+  UINT exit_code = ERROR_FILE_NOT_FOUND;
+  HMODULE chrome_tab = ::LoadLibrary(file_path);
+  CLM_ASSERT(chrome_tab);
+  if (chrome_tab) {
+    chrome_launcher::CfLaunchChromeProc proc = 
+        reinterpret_cast<chrome_launcher::CfLaunchChromeProc>(
+            ::GetProcAddress(chrome_tab, "CfLaunchChrome"));
+    CLM_ASSERT(proc);
+    if (proc) {
+      exit_code = proc();
+    } else {
+      exit_code = ERROR_INVALID_FUNCTION;
+    }
+
+    ::FreeLibrary(chrome_tab);
+  }
+  ::ExitProcess(exit_code);
+}