Windows: support long paths

Add implementations of open(2), mkdir(2), stat(2),
etc. that support long paths under Windows (paths
longer than MAX_PATH in <windows.h>, which is 260
characters).

The implementations are in a separate namespace
(google::protobuf::internal::win32), so they won't
collide with the standard implementations in
<io.h>, but after importing them with `using` they
can be drop-in replacements.

Fixes https://github.com/bazelbuild/bazel/issues/2634
Fixes https://github.com/google/protobuf/issues/2891

BUILD

@@ -108,6 +108,7 @@ cc_library(
         "src/google/protobuf/stubs/bytestream.cc",
         "src/google/protobuf/stubs/common.cc",
         "src/google/protobuf/stubs/int128.cc",
+        "src/google/protobuf/stubs/io_win32.cc",
         "src/google/protobuf/stubs/once.cc",
         "src/google/protobuf/stubs/status.cc",
         "src/google/protobuf/stubs/statusor.cc",
@@ -159,6 +160,7 @@ cc_library(
         "src/google/protobuf/service.cc",
         "src/google/protobuf/source_context.pb.cc",
         "src/google/protobuf/struct.pb.cc",
+        "src/google/protobuf/stubs/io_win32.cc",
         "src/google/protobuf/stubs/mathlimits.cc",
         "src/google/protobuf/stubs/substitute.cc",
         "src/google/protobuf/text_format.cc",
@@ -470,6 +472,7 @@ COMMON_TEST_SRCS = [
     # AUTOGEN(common_test_srcs)
     "src/google/protobuf/arena_test_util.cc",
     "src/google/protobuf/map_test_util.cc",
+    "src/google/protobuf/stubs/io_win32.cc",
     "src/google/protobuf/test_util.cc",
     "src/google/protobuf/testing/file.cc",
     "src/google/protobuf/testing/googletest.cc",
@@ -490,6 +493,16 @@ cc_binary(
     ],
 )
 
+cc_test(
+    name = "win32_test",
+    srcs = ["src/google/protobuf/stubs/io_win32_unittest.cc"],
+    deps = [
+        ":protobuf_lite",
+        "//external:gtest_main",
+    ],
+    tags = ["manual", "windows"],
+)
+
 cc_test(
     name = "protobuf_test",
     srcs = COMMON_TEST_SRCS + [
@@ -536,6 +549,7 @@ cc_test(
         "src/google/protobuf/stubs/bytestream_unittest.cc",
         "src/google/protobuf/stubs/common_unittest.cc",
         "src/google/protobuf/stubs/int128_unittest.cc",
+        "src/google/protobuf/stubs/io_win32_unittest.cc",
         "src/google/protobuf/stubs/once_unittest.cc",
         "src/google/protobuf/stubs/status_test.cc",
         "src/google/protobuf/stubs/statusor_test.cc",

cmake/extract_includes.bat.in

@@ -99,6 +99,7 @@ copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\casts.h" includ
 copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\common.h" include\google\protobuf\stubs\common.h
 copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\fastmem.h" include\google\protobuf\stubs\fastmem.h
 copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\hash.h" include\google\protobuf\stubs\hash.h
+copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\io_win32.h" include\google\protobuf\stubs\io_win32.h
 copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\logging.h" include\google\protobuf\stubs\logging.h
 copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\macros.h" include\google\protobuf\stubs\macros.h
 copy "${PROTOBUF_SOURCE_WIN32_PATH}\..\src\google\protobuf\stubs\mutex.h" include\google\protobuf\stubs\mutex.h

cmake/libprotobuf-lite.cmake

@@ -13,6 +13,7 @@ set(libprotobuf_lite_files
   ${protobuf_source_dir}/src/google/protobuf/stubs/bytestream.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/common.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/int128.cc
+  ${protobuf_source_dir}/src/google/protobuf/stubs/io_win32.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/once.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/status.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/statusor.cc

cmake/libprotoc.cmake

@@ -93,6 +93,7 @@ set(libprotoc_files
   ${protobuf_source_dir}/src/google/protobuf/compiler/ruby/ruby_generator.cc
   ${protobuf_source_dir}/src/google/protobuf/compiler/subprocess.cc
   ${protobuf_source_dir}/src/google/protobuf/compiler/zip_writer.cc
+  ${protobuf_source_dir}/src/google/protobuf/stubs/io_win32.cc
 )
 
 set(libprotoc_headers

cmake/tests.cmake

@@ -160,6 +160,8 @@ set(tests_files
   ${protobuf_source_dir}/src/google/protobuf/stubs/bytestream_unittest.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/common_unittest.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/int128_unittest.cc
+  ${protobuf_source_dir}/src/google/protobuf/stubs/io_win32.cc
+  ${protobuf_source_dir}/src/google/protobuf/stubs/io_win32_unittest.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/once_unittest.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/status_test.cc
   ${protobuf_source_dir}/src/google/protobuf/stubs/statusor_test.cc
@@ -198,6 +200,7 @@ target_link_libraries(tests libprotoc libprotobuf gmock_main)
 
 set(test_plugin_files
   ${protobuf_source_dir}/src/google/protobuf/compiler/mock_code_generator.cc
+  ${protobuf_source_dir}/src/google/protobuf/stubs/io_win32.cc
   ${protobuf_source_dir}/src/google/protobuf/testing/file.cc
   ${protobuf_source_dir}/src/google/protobuf/testing/file.h
   ${protobuf_source_dir}/src/google/protobuf/compiler/test_plugin.cc

src/Makefile.am

@@ -198,6 +198,8 @@ libprotobuf_lite_la_SOURCES =                                  \
   google/protobuf/stubs/hash.h                                 \
   google/protobuf/stubs/int128.cc                              \
   google/protobuf/stubs/int128.h                               \
+  google/protobuf/stubs/io_win32.cc                            \
+  google/protobuf/stubs/io_win32.h                             \
   google/protobuf/stubs/map_util.h                             \
   google/protobuf/stubs/mathutil.h                             \
   google/protobuf/stubs/once.cc                                \
@@ -761,6 +763,7 @@ protobuf_test_SOURCES =                                        \
   google/protobuf/stubs/bytestream_unittest.cc                 \
   google/protobuf/stubs/common_unittest.cc                     \
   google/protobuf/stubs/int128_unittest.cc                     \
+  google/protobuf/stubs/io_win32_unittest.cc                   \
   google/protobuf/stubs/once_unittest.cc                       \
   google/protobuf/stubs/statusor_test.cc                       \
   google/protobuf/stubs/status_test.cc                         \

src/google/protobuf/compiler/command_line_interface.cc

@@ -45,10 +45,7 @@
 #endif
 #include <sys/stat.h>
 #include <fcntl.h>
-#ifdef _MSC_VER
-#include <io.h>
-#include <direct.h>
-#else
+#ifndef _MSC_VER
 #include <unistd.h>
 #endif
 #include <errno.h>
@@ -80,6 +77,7 @@
 #include <google/protobuf/io/coded_stream.h>
 #include <google/protobuf/io/zero_copy_stream_impl.h>
 #include <google/protobuf/io/printer.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/stubs/strutil.h>
 #include <google/protobuf/stubs/substitute.h>
@@ -91,22 +89,6 @@ namespace google {
 namespace protobuf {
 namespace compiler {
 
-#if defined(_WIN32)
-#define mkdir(name, mode) mkdir(name)
-#ifndef W_OK
-#define W_OK 02  // not defined by MSVC for whatever reason
-#endif
-#ifndef F_OK
-#define F_OK 00  // not defined by MSVC for whatever reason
-#endif
-#ifndef STDIN_FILENO
-#define STDIN_FILENO 0
-#endif
-#ifndef STDOUT_FILENO
-#define STDOUT_FILENO 1
-#endif
-#endif
-
 #ifndef O_BINARY
 #ifdef _O_BINARY
 #define O_BINARY _O_BINARY
@@ -118,6 +100,14 @@ namespace compiler {
 namespace {
 #if defined(_WIN32) && !defined(__CYGWIN__)
 static const char* kPathSeparator = ";";
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::access;
+using google::protobuf::internal::win32::close;
+using google::protobuf::internal::win32::mkdir;
+using google::protobuf::internal::win32::open;
+using google::protobuf::internal::win32::setmode;
+using google::protobuf::internal::win32::write;
 #else
 static const char* kPathSeparator = ":";
 #endif
@@ -141,9 +131,9 @@ static bool IsWindowsAbsolutePath(const string& text) {
 
 void SetFdToTextMode(int fd) {
 #ifdef _WIN32
-  if (_setmode(fd, _O_TEXT) == -1) {
+  if (setmode(fd, _O_TEXT) == -1) {
     // This should never happen, I think.
-    GOOGLE_LOG(WARNING) << "_setmode(" << fd << ", _O_TEXT): " << strerror(errno);
+    GOOGLE_LOG(WARNING) << "setmode(" << fd << ", _O_TEXT): " << strerror(errno);
   }
 #endif
   // (Text and binary are the same on non-Windows platforms.)
@@ -151,9 +141,9 @@ void SetFdToTextMode(int fd) {
 
 void SetFdToBinaryMode(int fd) {
 #ifdef _WIN32
-  if (_setmode(fd, _O_BINARY) == -1) {
+  if (setmode(fd, _O_BINARY) == -1) {
     // This should never happen, I think.
-    GOOGLE_LOG(WARNING) << "_setmode(" << fd << ", _O_BINARY): " << strerror(errno);
+    GOOGLE_LOG(WARNING) << "setmode(" << fd << ", _O_BINARY): " << strerror(errno);
   }
 #endif
   // (Text and binary are the same on non-Windows platforms.)

src/google/protobuf/compiler/command_line_interface_unittest.cc

@@ -35,9 +35,7 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#ifdef _MSC_VER
-#include <io.h>
-#else
+#ifndef _MSC_VER
 #include <unistd.h>
 #endif
 #include <memory>
@@ -65,27 +63,27 @@
 #include <gtest/gtest.h>
 
 #include <google/protobuf/stubs/strutil.h>
+#include <google/protobuf/stubs/io_win32.h>
 
 namespace google {
 namespace protobuf {
 namespace compiler {
 
+#if defined(_WIN32)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::access;
+using google::protobuf::internal::win32::dup;
+using google::protobuf::internal::win32::dup2;
+using google::protobuf::internal::win32::close;
+using google::protobuf::internal::win32::open;
+using google::protobuf::internal::win32::write;
+#endif
+
 // Disable the whole test when we use tcmalloc for "draconian" heap checks, in
 // which case tcmalloc will print warnings that fail the plugin tests.
 #if !GOOGLE_PROTOBUF_HEAP_CHECK_DRACONIAN
 
-#if defined(_WIN32)
-#ifndef STDIN_FILENO
-#define STDIN_FILENO 0
-#endif
-#ifndef STDOUT_FILENO
-#define STDOUT_FILENO 1
-#endif
-#ifndef F_OK
-#define F_OK 00  // not defined by MSVC for whatever reason
-#endif
-#endif
-
 namespace {
 
 bool FileExists(const string& path) {

src/google/protobuf/compiler/importer.cc

@@ -33,7 +33,7 @@
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
 #ifdef _MSC_VER
-#include <io.h>
+#include <direct.h>
 #else
 #include <unistd.h>
 #endif
@@ -53,19 +53,21 @@
 #include <google/protobuf/compiler/parser.h>
 #include <google/protobuf/io/tokenizer.h>
 #include <google/protobuf/io/zero_copy_stream_impl.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/strutil.h>
 
-namespace google {
-namespace protobuf {
-namespace compiler {
-
 #ifdef _WIN32
-#ifndef F_OK
-#define F_OK 00  // not defined by MSVC for whatever reason
-#endif
 #include <ctype.h>
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::access;
+using google::protobuf::internal::win32::open;
 #endif
 
+namespace google {
+namespace protobuf {
+namespace compiler {
+
 // Returns true if the text looks like a Windows-style absolute path, starting
 // with a drive letter.  Example:  "C:\foo".  TODO(kenton):  Share this with
 // copy in command_line_interface.cc?

src/google/protobuf/compiler/objectivec/objectivec_helpers.cc

@@ -28,9 +28,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#ifdef _MSC_VER
-#include <io.h>
-#else
+#ifndef _MSC_VER
 #include <unistd.h>
 #endif
 #include <climits>
@@ -49,8 +47,15 @@
 #include <google/protobuf/io/printer.h>
 #include <google/protobuf/io/zero_copy_stream_impl.h>
 #include <google/protobuf/stubs/common.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/strutil.h>
 
+#if defined(_WIN32)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::open;
+#endif
+
 // NOTE: src/google/protobuf/compiler/plugin.cc makes use of cerr for some
 // error cases, so it seems to be ok to use as a back door for errors.
 

src/google/protobuf/compiler/plugin.cc

@@ -36,18 +36,12 @@
 #include <set>
 
 #ifdef _WIN32
-#include <io.h>
 #include <fcntl.h>
-#ifndef STDIN_FILENO
-#define STDIN_FILENO 0
-#endif
-#ifndef STDOUT_FILENO
-#define STDOUT_FILENO 1
-#endif
 #else
 #include <unistd.h>
 #endif
 
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/stubs/common.h>
 #include <google/protobuf/compiler/plugin.pb.h>
@@ -55,6 +49,11 @@
 #include <google/protobuf/descriptor.h>
 #include <google/protobuf/io/zero_copy_stream_impl.h>
 
+#if defined(_WIN32)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::setmode;
+#endif
 
 namespace google {
 namespace protobuf {
@@ -150,8 +149,8 @@ int PluginMain(int argc, char* argv[], const CodeGenerator* generator) {
   }
 
 #ifdef _WIN32
-  _setmode(STDIN_FILENO, _O_BINARY);
-  _setmode(STDOUT_FILENO, _O_BINARY);
+  setmode(STDIN_FILENO, _O_BINARY);
+  setmode(STDOUT_FILENO, _O_BINARY);
 #endif
 
   CodeGeneratorRequest request;

src/google/protobuf/io/zero_copy_stream_impl.cc

@@ -32,9 +32,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#ifdef _MSC_VER
-#include <io.h>
-#else
+#ifndef _MSC_VER
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -43,9 +41,9 @@
 #include <errno.h>
 #include <iostream>
 #include <algorithm>
-
 #include <google/protobuf/io/zero_copy_stream_impl.h>
 #include <google/protobuf/stubs/common.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/stubs/stl_util.h>
 
@@ -58,6 +56,13 @@ namespace io {
 // Win32 lseek is broken:  If invoked on a non-seekable file descriptor, its
 // return value is undefined.  We re-define it to always produce an error.
 #define lseek(fd, offset, origin) ((off_t)-1)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::access;
+using google::protobuf::internal::win32::close;
+using google::protobuf::internal::win32::open;
+using google::protobuf::internal::win32::read;
+using google::protobuf::internal::win32::write;
 #endif
 
 namespace {

src/google/protobuf/io/zero_copy_stream_unittest.cc

@@ -47,9 +47,7 @@
 //   implementations.
 
 
-#ifdef _MSC_VER
-#include <io.h>
-#else
+#ifndef _MSC_VER
 #include <unistd.h>
 #endif
 #include <stdlib.h>
@@ -72,6 +70,7 @@
 #endif
 
 #include <google/protobuf/stubs/common.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/testing/googletest.h>
 #include <google/protobuf/testing/file.h>
@@ -84,6 +83,12 @@ namespace {
 
 #ifdef _WIN32
 #define pipe(fds) _pipe(fds, 4096, O_BINARY)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::access;
+using google::protobuf::internal::win32::mkdir;
+using google::protobuf::internal::win32::open;
+using google::protobuf::internal::win32::close;
 #endif
 
 #ifndef O_BINARY

src/google/protobuf/message_unittest.cc

@@ -37,9 +37,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
-#ifdef _MSC_VER
-#include <io.h>
-#else
+#ifndef _MSC_VER
 #include <unistd.h>
 #endif
 #include <sstream>
@@ -56,6 +54,7 @@
 
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/stubs/common.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/testing/googletest.h>
 #include <gtest/gtest.h>
@@ -63,6 +62,13 @@
 namespace google {
 namespace protobuf {
 
+#if defined(_WIN32)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::close;
+using google::protobuf::internal::win32::open;
+#endif
+
 #ifndef O_BINARY
 #ifdef _O_BINARY
 #define O_BINARY _O_BINARY

src/google/protobuf/stubs/io_win32.h

+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// 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.
+
+// Author: laszlocsomor@google.com (Laszlo Csomor)
+//
+// This file contains the declarations for Windows implementations of
+// commonly used POSIX functions such as open(2) and access(2), as well
+// as macro definitions for flags of these functions.
+//
+// By including this file you'll redefine open/access/etc. to
+// ::google::protobuf::internal::win32::{open/access/etc.}.
+// Make sure you don't include a header that attempts to redeclare or
+// redefine these functions, that'll lead to confusing compilation
+// errors. It's best to #include this file as the last one to ensure that.
+//
+// This file is only used on Windows, it's empty on other platforms.
+
+#ifndef GOOGLE_PROTOBUF_STUBS_IO_WIN32_H__
+#define GOOGLE_PROTOBUF_STUBS_IO_WIN32_H__
+
+#if defined(_WIN32)
+
+#include <string>
+
+namespace google {
+namespace protobuf {
+namespace internal {
+namespace win32 {
+
+FILE* fopen(const char* path, const char* mode);
+int access(const char* path, int mode);
+int chdir(const char* path);
+int close(int fd);
+int dup(int fd);
+int dup2(int fd1, int fd2);
+int mkdir(const char* path, int _mode);
+int open(const char* path, int flags, int mode = 0);
+int read(int fd, void* buffer, size_t size);
+int setmode(int fd, int mode);
+int stat(const char* path, struct _stat* buffer);
+int write(int fd, const void* buffer, size_t size);
+std::wstring testonly_path_to_winpath(const std::string& path);
+
+}  // namespace win32
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+#ifndef W_OK
+#define W_OK 02  // not defined by MSVC for whatever reason
+#endif
+
+#ifndef F_OK
+#define F_OK 00  // not defined by MSVC for whatever reason
+#endif
+
+#ifndef STDIN_FILENO
+#define STDIN_FILENO 0
+#endif
+
+#ifndef STDOUT_FILENO
+#define STDOUT_FILENO 1
+#endif
+
+#endif  // defined(_WIN32)
+
+#endif  // GOOGLE_PROTOBUF_STUBS_IO_WIN32_H__
+
+

src/google/protobuf/testing/file.cc

@@ -38,24 +38,28 @@
 #ifdef _MSC_VER
 #define WIN32_LEAN_AND_MEAN  // yeah, right
 #include <windows.h>         // Find*File().  :(
-#include <io.h>
-#include <direct.h>
+// #include <direct.h>
 #else
 #include <dirent.h>
 #include <unistd.h>
 #endif
 #include <errno.h>
 
+#include <google/protobuf/stubs/io_win32.h>
+
 namespace google {
 namespace protobuf {
 
 #ifdef _WIN32
-#define mkdir(name, mode) mkdir(name)
 // Windows doesn't have symbolic links.
 #define lstat stat
-#ifndef F_OK
-#define F_OK 00  // not defined by MSVC for whatever reason
-#endif
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::access;
+using google::protobuf::internal::win32::chdir;
+using google::protobuf::internal::win32::fopen;
+using google::protobuf::internal::win32::mkdir;
+using google::protobuf::internal::win32::stat;
 #endif
 
 bool File::Exists(const string& name) {
@@ -113,6 +117,9 @@ void File::WriteStringToFileOrDie(const string& contents, const string& name) {
 }
 
 bool File::CreateDir(const string& name, int mode) {
+  if (!name.empty()) {
+    GOOGLE_CHECK_OK(name.back() != '.');
+  }
   return mkdir(name.c_str(), mode) == 0;
 }
 

src/google/protobuf/testing/googletest.cc

@@ -33,14 +33,14 @@
 
 #include <google/protobuf/testing/googletest.h>
 #include <google/protobuf/testing/file.h>
+#include <google/protobuf/stubs/io_win32.h>
 #include <google/protobuf/stubs/strutil.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
 #include <stdlib.h>
 #ifdef _MSC_VER
-#include <io.h>
-#include <direct.h>
+// #include <direct.h>
 #else
 #include <unistd.h>
 #endif
@@ -53,7 +53,13 @@ namespace google {
 namespace protobuf {
 
 #ifdef _WIN32
-#define mkdir(name, mode) mkdir(name)
+// DO NOT include <io.h>, instead create functions in io_win32.{h,cc} and import
+// them like we do below.
+using google::protobuf::internal::win32::close;
+using google::protobuf::internal::win32::dup2;
+using google::protobuf::internal::win32::dup;
+using google::protobuf::internal::win32::mkdir;
+using google::protobuf::internal::win32::open;
 #endif
 
 #ifndef O_BINARY
@@ -111,14 +117,32 @@ string GetTemporaryDirectoryName() {
   char b[L_tmpnam + 1];     // HPUX multithread return 0 if s is 0
   string result = tmpnam(b);
 #ifdef _WIN32
+  // Avoid a trailing dot by changing it to an underscore. On Win32 the names of
+  // files and directories can, but should not, end with dot.
+  //
+  // In MS-DOS and FAT16 filesystem the filenames were 8dot3 style so it didn't
+  // make sense to have a name ending in dot without an extension, so the shell
+  // silently ignored trailing dots. To this day the Win32 API still maintains
+  // this behavior and silently ignores trailing dots in path arguments of
+  // functions such as CreateFile{A,W}. Even POSIX API function implementations
+  // seem to wrap the Win32 API functions (e.g. CreateDirectoryA) and behave
+  // this way.
+  // It's possible to avoid this behavior and create files / directories with
+  // trailing dots (using CreateFileW / CreateDirectoryW and prefixing the path
+  // with "\\?\") but these will be degenerate in the sense that you cannot
+  // chdir into such directories (or navigate into them with Windows Explorer)
+  // nor can you open such files with some programs (e.g. Notepad).
+  if (result.back() == '.') {
+    result[result.size() - 1] = '_';
+  }
   // On Win32, tmpnam() returns a file prefixed with '\', but which is supposed
   // to be used in the current working directory.  WTF?
   if (HasPrefixString(result, "\\")) {
     result.erase(0, 1);
   }
-  // The Win32 API accepts forward slashes as a path delimiter even though
-  // backslashes are standard.  Let's avoid confusion and use only forward
-  // slashes.
+  // The Win32 API accepts forward slashes as a path delimiter as long as the
+  // path doesn't use the "\\?\" prefix.
+  // Let's avoid confusion and use only forward slashes.
   result = StringReplace(result, "\\", "/", true);
 #endif  // _WIN32
   return result;