From 74da61623fbf416e50e5cbe0145ac470d8d357e7 Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sat, 27 Jan 2024 16:04:46 +0800
Subject: [PATCH 1/9] feat: supports unicode paths

---
 src/base/commandlineflags.h |  26 ++-
 src/flags.cc                |  48 +++-
 src/glog/flags.h            |  19 ++
 src/glog/logging.h          |  10 +-
 src/googletest.h            |  15 +-
 src/logging.cc              | 450 +++++++++++++++++++++++-------------
 src/utilities.h             |  54 +++++
 7 files changed, 448 insertions(+), 174 deletions(-)

diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h
index 3d31a861f..f7bd5ac2c 100644
--- a/src/base/commandlineflags.h
+++ b/src/base/commandlineflags.h
@@ -56,11 +56,12 @@
 
 #ifdef GLOG_USE_GFLAGS
 
-#  include <gflags/gflags.h>
+#include <gflags/gflags.h>
 
 #else
 
-#  include "glog/logging.h"
+#include "glog/logging.h"
+#include "utilities.h"
 
 #  define DECLARE_VARIABLE(type, shorttype, name, tn) \
     namespace fL##shorttype {                         \
@@ -107,6 +108,18 @@
     }                                                           \
     using fLS::FLAGS_##name
 
+#define DECLARE_wstring(name)                       \
+  namespace fLS {                                   \
+  extern GLOG_EXPORT std::wstring& FLAGS_##name;    \
+  }                                                 \
+  using fLS::FLAGS_##name
+#define DEFINE_wstring(name, value, meaning)                            \
+    namespace fLS {                                                     \
+        std::wstring FLAGS_##name##_buf(value);                         \
+        GLOG_EXPORT std::wstring& FLAGS_##name = FLAGS_##name##_buf;    \
+        wchar_t FLAGS_no##name;                                         \
+    }                                                                   \
+    using fLS::FLAGS_##name     
 #endif  // GLOG_USE_GFLAGS
 
 // Define GLOG_DEFINE_* using DEFINE_* . By using these macros, we
@@ -128,10 +141,17 @@
 #define GLOG_DEFINE_string(name, value, meaning) \
   DEFINE_string(name, EnvToString("GLOG_" #name, value), meaning)
 
+#define GLOG_DEFINE_wstring(name, value, meaning) \
+  DEFINE_wstring(name, EnvToString(L"GLOG_" #name, value), meaning)
+
+
 // These macros (could be functions, but I don't want to bother with a .cc
 // file), make it easier to initialize flags from the environment.
 
-#define EnvToString(envname, dflt) (!getenv(envname) ? (dflt) : getenv(envname))
+#define EnvToString(envname, dflt) \
+  (google::logging::internal::getenv(envname).empty() \
+       ? (dflt)                                         \
+       : google::logging::internal::getenv(envname))
 
 #define EnvToBool(envname, dflt) \
   (!getenv(envname) ? (dflt)     \
diff --git a/src/flags.cc b/src/flags.cc
index c4c2aa4b2..ca4a4766a 100644
--- a/src/flags.cc
+++ b/src/flags.cc
@@ -32,22 +32,46 @@
 
 #include <cstdlib>
 #include <cstring>
-
+#include <array>
 #include "base/commandlineflags.h"
 #include "glog/log_severity.h"
 
 namespace {
 
 // Compute the default value for --log_dir
-static const char* DefaultLogDir() {
-  constexpr const char* const names[]{"GOOGLE_LOG_DIR", "TEST_TMPDIR"};
-  for (const char* const name : names) {
-    const char* const env = std::getenv(name);
-    if (env != nullptr && env[0] != '\0') {
-      return env;
+
+ template <class Ch, int N>
+std::basic_string<Ch> DefaultLogDir(const std::array<const Ch*, N>& names) {
+  for (const Ch*  name : names) {
+    auto val = google::logging::internal::getenv(name);
+    if(!val.empty()) {
+      return val;
     }
+   
+  }
+  return {};
+ }
+
+template<class Ch>
+struct LogDirEnvVar;
+
+template <>
+struct LogDirEnvVar<char> {
+  constexpr static std::array<const char*, 2> names() noexcept {
+    return {"GOOGLE_LOG_DIR", "TEST_TMPDIR"};
   }
-  return "";
+};
+
+template <>
+struct LogDirEnvVar<wchar_t> {
+  constexpr static std::array<const wchar_t*, 2> names() noexcept {
+    return {L"GOOGLE_LOG_DIR", L"TEST_TMPDIR"};
+  }
+};
+
+template <class Ch>
+decltype(auto) DefaultLogDir() {
+  return DefaultLogDir<Ch, 2>(LogDirEnvVar<Ch>::names());
 }
 
 bool BoolFromEnv(const char* varname, bool defval) {
@@ -123,9 +147,15 @@ GLOG_DEFINE_string(logmailer, "", "Mailer used to send logging email");
 GLOG_DEFINE_int32(logfile_mode, 0664, "Log file mode/permissions.");
 
 GLOG_DEFINE_string(
-    log_dir, DefaultLogDir(),
+    log_dir, DefaultLogDir<char>(),
     "If specified, logfiles are written into this directory instead "
     "of the default logging directory.");
+
+GLOG_DEFINE_wstring(
+    log_wdir, DefaultLogDir<wchar_t>(),
+    L"If specified, logfiles are written into this directory instead "
+    L"of the default logging directory.");
+
 GLOG_DEFINE_string(log_link, "",
                    "Put additional links to the log "
                    "files in this directory");
diff --git a/src/glog/flags.h b/src/glog/flags.h
index 8349639a6..92ea1ce93 100644
--- a/src/glog/flags.h
+++ b/src/glog/flags.h
@@ -51,6 +51,7 @@
 #pragma push_macro("DECLARE_VARIABLE")
 #pragma push_macro("DECLARE_bool")
 #pragma push_macro("DECLARE_string")
+#pragma push_macro("DECLARE_wstring")
 #pragma push_macro("DECLARE_int32")
 #pragma push_macro("DECLARE_uint32")
 
@@ -66,6 +67,10 @@
 #  undef DECLARE_string
 #endif
 
+#ifdef DECLARE_wstring
+#  undef DECLARE_wstring
+#endif
+
 #ifdef DECLARE_int32
 #  undef DECLARE_int32
 #endif
@@ -100,8 +105,17 @@
     extern GLOG_EXPORT std::string& FLAGS_##name; \
     }                                             \
     using fLS::FLAGS_##name
+
+#define DECLARE_wstring(name)                    \
+  namespace fLS {                                \
+  extern GLOG_EXPORT std::wstring& FLAGS_##name; \
+  }                                              \
+  using fLS::FLAGS_##name
+
 #endif
 
+
+
 DECLARE_int32(logemaillevel);
 DECLARE_int32(logcleansecs);
 
@@ -157,6 +171,10 @@ DECLARE_int32(minloglevel);
 // default logging directory.
 DECLARE_string(log_dir);
 
+// If specified, logfiles are written into this directory instead of the
+// default logging directory.
+DECLARE_wstring(log_wdir);
+
 // Set the log file mode.
 DECLARE_int32(logfile_mode);
 
@@ -185,6 +203,7 @@ DECLARE_bool(symbolize_stacktrace);
 #pragma pop_macro("DECLARE_VARIABLE")
 #pragma pop_macro("DECLARE_bool")
 #pragma pop_macro("DECLARE_string")
+#pragma pop_macro("DECLARE_wstring")
 #pragma pop_macro("DECLARE_int32")
 #pragma pop_macro("DECLARE_uint32")
 
diff --git a/src/glog/logging.h b/src/glog/logging.h
index 6e3ea2615..0df40f188 100644
--- a/src/glog/logging.h
+++ b/src/glog/logging.h
@@ -1493,6 +1493,9 @@ GLOG_EXPORT void FlushLogFilesUnsafe(LogSeverity min_severity);
 GLOG_EXPORT void SetLogDestination(LogSeverity severity,
                                    const char* base_filename);
 
+GLOG_EXPORT void SetLogDestination(LogSeverity severity,
+                                   const wchar_t* base_filename);
+
 //
 // Set the basename of the symlink to the latest log file at a given
 // severity.  If symlink_basename is empty, do not make a symlink.  If
@@ -1501,7 +1504,8 @@ GLOG_EXPORT void SetLogDestination(LogSeverity severity,
 //
 GLOG_EXPORT void SetLogSymlink(LogSeverity severity,
                                const char* symlink_basename);
-
+GLOG_EXPORT void SetLogSymlink(LogSeverity severity,
+                               const wchar_t* symlink_basename);
 //
 // Used to send logs to some other kind of destination
 // Users should subclass LogSink and override send to do whatever they want.
@@ -1557,6 +1561,7 @@ GLOG_EXPORT void RemoveLogSink(LogSink* destination);
 // name.  Thread-safe.
 //
 GLOG_EXPORT void SetLogFilenameExtension(const char* filename_extension);
+GLOG_EXPORT void SetLogFilenameExtension(const wchar_t* filename_extension);
 
 //
 // Make it so that all log messages of at least a particular severity
@@ -1584,7 +1589,8 @@ GLOG_EXPORT void SetEmailLogging(LogSeverity min_severity,
 GLOG_EXPORT bool SendEmail(const char* dest, const char* subject,
                            const char* body);
 
-GLOG_EXPORT const std::vector<std::string>& GetLoggingDirectories();
+GLOG_EXPORT const std::vector<std::string> GetLoggingDirectories();
+GLOG_EXPORT const std::vector<std::wstring>& GetLoggingDirectoriesW();
 
 // Print any fatal message again -- useful to call from signal handler
 // so that the last thing in the output is the fatal message.
diff --git a/src/googletest.h b/src/googletest.h
index 971c5b401..8e9483eb3 100644
--- a/src/googletest.h
+++ b/src/googletest.h
@@ -70,11 +70,12 @@
 
 using std::map;
 using std::string;
+using std::wstring;
 using std::vector;
 
 namespace google {
 extern void (*g_logging_fail_func)();
-extern void GetExistingTempDirectories(std::vector<std::string>& list);
+extern void GetExistingTempDirectories(std::vector<std::wstring>& list);
 extern int posix_strerror_r(int err, char* buf, size_t len);
 extern std::string StrError(int err);
 }  // namespace google
@@ -82,12 +83,12 @@ extern std::string StrError(int err);
 #undef GLOG_EXPORT
 #define GLOG_EXPORT
 
-static inline string GetTempDir() {
-  vector<string> temp_directories_list;
+static inline wstring GetTempDirW() {
+  vector<wstring> temp_directories_list;
   google::GetExistingTempDirectories(temp_directories_list);
 
   if (temp_directories_list.empty()) {
-    fprintf(stderr, "No temporary directory found\n");
+    fwprintf(stderr, L"No temporary directory found\n");
     exit(EXIT_FAILURE);
   }
 
@@ -95,6 +96,12 @@ static inline string GetTempDir() {
   return temp_directories_list.front();
 }
 
+static inline string GetTempDir() { 
+  wstring temp_dir = GetTempDirW();
+  return google::logging::internal::StrConvert<wchar_t, char>(temp_dir);
+}
+
+
 #if defined(GLOG_OS_WINDOWS) && defined(_MSC_VER) && !defined(TEST_SRC_DIR)
 // The test will run in glog/vsproject/<project name>
 // (e.g., glog/vsproject/logging_unittest).
diff --git a/src/logging.cc b/src/logging.cc
index f95fb617a..4078415ab 100644
--- a/src/logging.cc
+++ b/src/logging.cc
@@ -72,6 +72,7 @@
 #include <regex>
 #include <sstream>
 #include <vector>
+#include <array>
 
 #ifdef HAVE__CHSIZE_S
 #  include <io.h>  // for truncate log file
@@ -106,6 +107,7 @@ using std::ostringstream;
 using std::setfill;
 using std::setw;
 using std::string;
+using std::wstring;
 using std::vector;
 
 using std::fclose;
@@ -123,7 +125,12 @@ using std::fdopen;
 #define EXCLUSIVE_LOCKS_REQUIRED(mu)
 
 // TODO(hamaji): consider windows
-enum { PATH_SEPARATOR = '/' };
+#ifdef  GLOG_OS_WINDOWS
+const wchar_t * const PATH_SEPARATOR = L"\\/";
+#else
+const wchar_t* const PATH_SEPARATOR = L"/";
+#endif  //  GLOG_OS_WINDOWS
+
 
 #ifndef HAVE_PREAD
 static ssize_t pread(int fd, void* buf, size_t count, off_t offset) {
@@ -149,6 +156,113 @@ static ssize_t pwrite(int fd, void* buf, size_t count, off_t offset) {
 }
 #endif  // !HAVE_PWRITE
 
+namespace details {
+int open(const char* filename, int flags, mode_t mode) {
+  return ::open(filename, flags, mode);
+}
+
+int open(const wchar_t* filename, int flags, mode_t mode) {
+#ifdef GLOG_OS_WINDOWS
+  return _wopen(filename, flags, mode);
+#else
+  auto str_filename = google::logging::internal::StrConvert<wchar_t, char>(filename);
+  return open(str_filename.c_str(), flags, mode);
+#endif  //  GLOG_OS_WINDOWS
+}
+
+int unlink(const char* filename) { 
+    return ::unlink(filename); 
+}
+int unlink(const wchar_t* filename) { 
+#ifdef GLOG_OS_WINDOWS
+  return ::_wunlink(filename); 
+#else
+  auto str_filename = google::logging::internal::StrConvert<wchar_t, char>(filename);
+  return unlink(str_filename.c_str());
+#endif
+}
+
+int symlink(const char* dest, const char* src) {
+#ifdef GLOG_OS_WINDOWS
+  // the CreateSymbolicLinkA func requires  a privilege
+  return ::CreateSymbolicLinkA(dest, src, 0x0) == 0 ? GetLastError() : 0;
+#elif defined(HAVE_UNISTD_H)
+  return ::symlink(dest, src);
+#endif  // GLOG_OS_WINDOWS
+}
+
+int symlink(const wchar_t* target, const wchar_t* symlink_file) {
+#ifdef GLOG_OS_WINDOWS
+  return ::CreateSymbolicLinkW(symlink_file, target, 0x0) == 0 ? GetLastError()
+                                                               : 0;
+#elif defined(HAVE_UNISTD_H)
+  auto str_target = google::logging::internal::StrConvert<wchar_t, char>(target);
+  auto str_symlink_file =
+      google::logging::internal::StrConvert<wchar_t, char>(symlink_file);
+  return symlink(str_target.c_str(), str_symlink_file.c_str());
+#endif  // GLOG_OS_WINDOWS
+}
+
+decltype(auto) opendir(const char* dir_name) { return ::opendir(dir_name); }
+decltype(auto) opendir(const wchar_t* dir_name) {
+#ifdef GLOG_OS_WINDOWS
+  return ::wopendir(dir_name);
+#else 
+  auto str_dir = google::logging::internal::StrConvert<wchar_t, char>(dir_name);
+  return opendir(str_dir.c_str());
+#endif  // GLOG_OS_WINDOWS
+}
+
+dirent* readdir(DIR* dir) { return ::readdir(dir); }
+int closedir(DIR* dir) { return ::closedir(dir); }
+#ifdef GLOG_OS_WINDOWS
+wdirent* readdir(WDIR* dir) { return ::wreaddir(dir); }
+int closedir(WDIR* dir) { return ::wclosedir(dir); }
+#endif  // GLOG_OS_WINDOWS
+
+#ifdef  GLOG_OS_WINDOWS
+typedef struct _stat64i32 wstat;
+#else
+typedef  struct stat wstat;
+#endif  //  GLOG_OS_WINDOWS
+
+int stat(const char* filename, struct stat* const s) {
+  return ::stat(filename, s);
+}
+int stat(const wchar_t* filename, wstat* s) {
+#ifdef GLOG_OS_WINDOWS
+  return ::_wstat(filename, s);
+#else
+  auto str_filename =
+      google::logging::internal::StrConvert<wchar_t, char>(filename);
+  return ::stat(str_filename.c_str(), s);
+#endif  // GLOG_OS_WINDOWS
+}
+int access(const char* dir_name, int access_mode) {
+  return ::access(dir_name, access_mode);
+}
+int access(const wchar_t* dir_name, int access_mode) {
+#ifdef GLOG_OS_WINDOWS
+  return ::_waccess(dir_name, access_mode);
+#else
+  auto str_dir_name =
+      google::logging::internal::StrConvert<wchar_t, char>(dir_name);
+  return ::access(str_dir_name.c_str(), access_mode);
+#endif  // GLOG_OS_WINDOWS
+}
+void perror(const char* msg) {
+  ::perror(msg);
+}
+void perror(const wchar_t *msg) {
+#ifdef GLOG_OS_WINDOWS
+  _wperror(msg);
+#else
+  auto str_msg =  google::logging::internal::StrConvert<wchar_t, char>(msg);
+  perror(str_msg.c_str());
+#endif
+}
+}  // namespace details
+
 static void GetHostName(string* hostname) {
 #if defined(HAVE_SYS_UTSNAME_H)
   struct utsname buf;
@@ -329,8 +443,9 @@ int64 LogMessage::num_messages_[NUM_SEVERITIES] = {0, 0, 0, 0};
 static bool stop_writing = false;
 
 const char* const LogSeverityNames[] = {"INFO", "WARNING", "ERROR", "FATAL"};
-
-// Has the user called SetExitOnDFatal(true)?
+const wchar_t* const LogSeverityNamesW[] = {L"INFO", L"WARNING", L"ERROR",
+                                           L"FATAL"};
+    // Has the user called SetExitOnDFatal(true)?
 static bool exit_on_dfatal = true;
 
 const char* GetLogSeverityName(LogSeverity severity) {
@@ -365,7 +480,6 @@ void base::Logger::Write(bool force_flush,
 }
 
 namespace {
-
 constexpr std::intmax_t kSecondsInDay = 60 * 60 * 24;
 constexpr std::intmax_t kSecondsInWeek = kSecondsInDay * 7;
 
@@ -446,7 +560,7 @@ std::unique_ptr<PrefixFormatter> g_prefix_formatter;
 // Encapsulates all file-system related state
 class LogFileObject : public base::Logger {
  public:
-  LogFileObject(LogSeverity severity, const char* base_filename);
+  LogFileObject(LogSeverity severity, const wchar_t* base_filename);
   ~LogFileObject() override;
 
   void Write(bool force_flush,  // Should we force a flush here?
@@ -455,9 +569,9 @@ class LogFileObject : public base::Logger {
              const char* message, size_t message_len) override;
 
   // Configuration options
-  void SetBasename(const char* basename);
-  void SetExtension(const char* ext);
-  void SetSymlinkBasename(const char* symlink_basename);
+  void SetBasename(const wchar_t* basename);
+  void SetExtension(const wchar_t* ext);
+  void SetSymlinkBasename(const wchar_t* symlink_basename);
 
   // Normal flushing routine
   void Flush() override;
@@ -479,9 +593,9 @@ class LogFileObject : public base::Logger {
 
   std::mutex mutex_;
   bool base_filename_selected_;
-  string base_filename_;
-  string symlink_basename_;
-  string filename_extension_;  // option users can specify (eg to add port#)
+  wstring base_filename_;
+  wstring symlink_basename_;
+  wstring filename_extension_;  // option users can specify (eg to add port#)
   std::unique_ptr<FILE> file_;
   LogSeverity severity_;
   uint32 bytes_since_flush_{0};
@@ -495,7 +609,9 @@ class LogFileObject : public base::Logger {
   // Actually create a logfile using the value of base_filename_ and the
   // optional argument time_pid_string
   // REQUIRES: lock_ is held
-  bool CreateLogfile(const string& time_pid_string);
+  bool CreateLogfile(const wstring& time_pid_string);
+  void CreateSymlink(const wstring& link_des_w, const wstring& link_path_w,
+                     const wstring& line_name_w);
 };
 
 // Encapsulate all log cleaner related states
@@ -508,23 +624,23 @@ class LogCleaner {
   void Disable();
 
   void Run(const std::chrono::system_clock::time_point& current_time,
-           bool base_filename_selected, const string& base_filename,
-           const string& filename_extension);
+           bool base_filename_selected, const wstring& base_filename,
+           const wstring& filename_extension);
 
   bool enabled() const { return enabled_; }
 
  private:
-  vector<string> GetOverdueLogNames(
-      string log_directory,
+  vector<std::wstring> GetOverdueLogNames(
+      const std::wstring &log_directory,
       const std::chrono::system_clock::time_point& current_time,
-      const string& base_filename, const string& filename_extension) const;
+      const std::wstring& base_filename, const std::wstring& filename_extension) const;
 
-  bool IsLogFromCurrentProject(const string& filepath,
-                               const string& base_filename,
-                               const string& filename_extension) const;
+  bool IsLogFromCurrentProject(const std::wstring& filepath,
+                               const std::wstring& base_filename,
+                               const std::wstring& filename_extension) const;
 
   bool IsLogLastModifiedOver(
-      const string& filepath,
+      const std::wstring& filepath,
       const std::chrono::system_clock::time_point& current_time) const;
 
   bool enabled_{false};
@@ -547,11 +663,11 @@ class LogDestination {
 
   // These methods are just forwarded to by their global versions.
   static void SetLogDestination(LogSeverity severity,
-                                const char* base_filename);
-  static void SetLogSymlink(LogSeverity severity, const char* symlink_basename);
+                                const wchar_t* base_filename);
+  static void SetLogSymlink(LogSeverity severity, const wchar_t* symlink_basename);
   static void AddLogSink(LogSink* destination);
   static void RemoveLogSink(LogSink* destination);
-  static void SetLogFilenameExtension(const char* filename_extension);
+  static void SetLogFilenameExtension(const wchar_t* filename_extension);
   static void SetStderrLogging(LogSeverity min_severity);
   static void SetEmailLogging(LogSeverity min_severity, const char* addresses);
   static void LogToStderr();
@@ -570,7 +686,7 @@ class LogDestination {
   }
 
   static void DeleteLogDestinations();
-  LogDestination(LogSeverity severity, const char* base_filename);
+  LogDestination(LogSeverity severity, const wchar_t* base_filename);
 
  private:
 #if defined(__cpp_lib_shared_mutex) && (__cpp_lib_shared_mutex >= 201505L)
@@ -669,7 +785,7 @@ const string& LogDestination::hostname() {
   return hostname_;
 }
 
-LogDestination::LogDestination(LogSeverity severity, const char* base_filename)
+LogDestination::LogDestination(LogSeverity severity, const wchar_t* base_filename)
     : fileobject_(severity, base_filename), logger_(&fileobject_) {}
 
 LogDestination::~LogDestination() { ResetLoggerImpl(); }
@@ -715,7 +831,7 @@ inline void LogDestination::FlushLogFiles(int min_severity) {
 }
 
 inline void LogDestination::SetLogDestination(LogSeverity severity,
-                                              const char* base_filename) {
+                                              const wchar_t* base_filename) {
   // Prevent any subtle race conditions by wrapping a mutex lock around
   // all this stuff.
   std::lock_guard<std::mutex> l{log_mutex};
@@ -723,7 +839,7 @@ inline void LogDestination::SetLogDestination(LogSeverity severity,
 }
 
 inline void LogDestination::SetLogSymlink(LogSeverity severity,
-                                          const char* symlink_basename) {
+                                          const wchar_t* symlink_basename) {
   CHECK_GE(severity, 0);
   CHECK_LT(severity, NUM_SEVERITIES);
   std::lock_guard<std::mutex> l{log_mutex};
@@ -749,7 +865,7 @@ inline void LogDestination::RemoveLogSink(LogSink* destination) {
   }
 }
 
-inline void LogDestination::SetLogFilenameExtension(const char* ext) {
+inline void LogDestination::SetLogFilenameExtension(const wchar_t* ext) {
   // Prevent any subtle race conditions by wrapping a mutex lock around
   // all this stuff.
   std::lock_guard<std::mutex> l{log_mutex};
@@ -771,8 +887,7 @@ inline void LogDestination::LogToStderr() {
   // SetLogDestination already do the locking!
   SetStderrLogging(GLOG_INFO);  // thus everything is "also" logged to stderr
   for (int i = 0; i < NUM_SEVERITIES; ++i) {
-    SetLogDestination(static_cast<LogSeverity>(i),
-                      "");  // "" turns off logging to a logfile
+    SetLogDestination(static_cast<LogSeverity>(i), L"");  // "" turns off logging to a logfile
   }
 }
 
@@ -972,11 +1087,10 @@ void SetApplicationFingerprint(const std::string& fingerprint) {
 
 namespace {
 
-// Directory delimiter; Windows supports both forward slashes and backslashes
 #ifdef GLOG_OS_WINDOWS
-const char possible_dir_delim[] = {'\\', '/'};
+const wchar_t possible_dir_delim[] = {L'\\', L'/'};
 #else
-const char possible_dir_delim[] = {'/'};
+const wchar_t possible_dir_delim[] = {L'/'};
 #endif
 
 string PrettyDuration(const std::chrono::duration<int>& secs) {
@@ -990,10 +1104,10 @@ string PrettyDuration(const std::chrono::duration<int>& secs) {
   return result.str();
 }
 
-LogFileObject::LogFileObject(LogSeverity severity, const char* base_filename)
+LogFileObject::LogFileObject(LogSeverity severity, const wchar_t* base_filename)
     : base_filename_selected_(base_filename != nullptr),
-      base_filename_((base_filename != nullptr) ? base_filename : ""),
-      symlink_basename_(glog_internal_namespace_::ProgramInvocationShortName()),
+      base_filename_((base_filename != nullptr) ? base_filename : L""),
+      symlink_basename_(logging::internal::StrConvert<char, wchar_t>(glog_internal_namespace_::ProgramInvocationShortName())),
       filename_extension_(),
       severity_(severity),
       rollover_attempt_(kRolloverAttemptFrequency - 1),
@@ -1004,7 +1118,7 @@ LogFileObject::~LogFileObject() {
   file_ = nullptr;
 }
 
-void LogFileObject::SetBasename(const char* basename) {
+void LogFileObject::SetBasename(const wchar_t* basename) {
   std::lock_guard<std::mutex> l{mutex_};
   base_filename_selected_ = true;
   if (base_filename_ != basename) {
@@ -1017,7 +1131,7 @@ void LogFileObject::SetBasename(const char* basename) {
   }
 }
 
-void LogFileObject::SetExtension(const char* ext) {
+void LogFileObject::SetExtension(const wchar_t* ext) {
   std::lock_guard<std::mutex> l{mutex_};
   if (filename_extension_ != ext) {
     // Get rid of old log file since we are changing names
@@ -1029,7 +1143,7 @@ void LogFileObject::SetExtension(const char* ext) {
   }
 }
 
-void LogFileObject::SetSymlinkBasename(const char* symlink_basename) {
+void LogFileObject::SetSymlinkBasename(const wchar_t* symlink_basename) {
   std::lock_guard<std::mutex> l{mutex_};
   symlink_basename_ = symlink_basename;
 }
@@ -1051,21 +1165,21 @@ void LogFileObject::FlushUnlocked(
                 std::chrono::duration<int32>{FLAGS_logbufsecs});
 }
 
-bool LogFileObject::CreateLogfile(const string& time_pid_string) {
-  string string_filename = base_filename_;
+bool LogFileObject::CreateLogfile(const wstring& time_pid_string) {
+  wstring string_filename = base_filename_;
   if (FLAGS_timestamp_in_logfile_name) {
     string_filename += time_pid_string;
   }
   string_filename += filename_extension_;
-  const char* filename = string_filename.c_str();
   // only write to files, create if non-existant.
   int flags = O_WRONLY | O_CREAT;
   if (FLAGS_timestamp_in_logfile_name) {
     // demand that the file is unique for our timestamp (fail if it exists).
     flags = flags | O_EXCL;
   }
-  FileDescriptor fd{
-      open(filename, flags, static_cast<mode_t>(FLAGS_logfile_mode))};
+  FileDescriptor fd{details::open(string_filename.c_str(), flags,
+                           static_cast<mode_t>(FLAGS_logfile_mode))};
+
   if (!fd) return false;
 #ifdef HAVE_FCNTL
   // Mark the file close-on-exec. We don't really care if this fails
@@ -1098,7 +1212,9 @@ bool LogFileObject::CreateLogfile(const string& time_pid_string) {
   file_.reset(fdopen(fd.release(), "a"));  // Make a FILE*.
   if (file_ == nullptr) {                  // Man, we're screwed!
     if (FLAGS_timestamp_in_logfile_name) {
-      unlink(filename);  // Erase the half-baked evidence: an unusable log file,
+      details::unlink(string_filename.c_str());  // Erase the half-baked evidence: an
+                                          // unusable log
+                           // file,
                          // only if we just created it.
     }
     return false;
@@ -1119,41 +1235,36 @@ bool LogFileObject::CreateLogfile(const string& time_pid_string) {
   // no error.
   if (!symlink_basename_.empty()) {
     // take directory from filename
-    const char* slash = strrchr(filename, PATH_SEPARATOR);
-    const string linkname =
-        symlink_basename_ + '.' + LogSeverityNames[severity_];
-    string linkpath;
-    if (slash)
-      linkpath = string(
-          filename, static_cast<size_t>(slash - filename + 1));  // get dirname
+    std::size_t slash = string_filename.find_last_of(PATH_SEPARATOR);
+    const wstring linkname =
+        symlink_basename_ + L'.' + LogSeverityNamesW[severity_];
+    wstring linkpath;
+    if (slash != std::string::npos)
+      linkpath = string_filename.substr(0, slash + 1);  // get dirname
     linkpath += linkname;
-    unlink(linkpath.c_str());  // delete old one if it exists
+    details::unlink(linkpath.c_str());  // delete old one if it exists
 
-#if defined(GLOG_OS_WINDOWS)
-    // TODO(hamaji): Create lnk file on Windows?
-#elif defined(HAVE_UNISTD_H)
-    // We must have unistd.h.
-    // Make the symlink be relative (in the same dir) so that if the
-    // entire log directory gets relocated the link is still valid.
-    const char* linkdest = slash ? (slash + 1) : filename;
-    if (symlink(linkdest, linkpath.c_str()) != 0) {
-      // silently ignore failures
-    }
 
-    // Make an additional link to the log file in a place specified by
-    // FLAGS_log_link, if indicated
-    if (!FLAGS_log_link.empty()) {
-      linkpath = FLAGS_log_link + "/" + linkname;
-      unlink(linkpath.c_str());  // delete old one if it exists
-      if (symlink(filename, linkpath.c_str()) != 0) {
-        // silently ignore failures
-      }
-    }
-#endif
+    wstring link_dest = slash != std::string::npos
+                            ? (string_filename.substr(slash + 1))
+                            : string_filename;
+    CreateSymlink(link_dest, linkpath, linkname);
   }
 
   return true;  // Everything worked
 }
+void LogFileObject::CreateSymlink(const wstring& link_dest_w,
+                                  const wstring& link_path_w,
+                                  const wstring& link_name_w) {
+  details::symlink(link_dest_w.c_str(), link_path_w.c_str());
+  if (!FLAGS_log_link.empty()) {
+    auto new_link_path =
+        logging::internal::StrConvert<char, wchar_t>(FLAGS_log_link) + L"/" +
+        link_name_w;
+    details::unlink(new_link_path.c_str());
+    details::symlink(link_dest_w.c_str(), new_link_path.c_str());
+  }
+}
 
 void LogFileObject::Write(
     bool force_flush, const std::chrono::system_clock::time_point& timestamp,
@@ -1199,18 +1310,18 @@ void LogFileObject::Write(
     }
 
     // The logfile's filename will have the date/time & pid in it
-    ostringstream time_pid_stream;
-    time_pid_stream.fill('0');
+    std::wostringstream time_pid_stream;
+    time_pid_stream.fill(L'0');
     time_pid_stream << 1900 + tm_time.tm_year << setw(2) << 1 + tm_time.tm_mon
-                    << setw(2) << tm_time.tm_mday << '-' << setw(2)
+                    << setw(2) << tm_time.tm_mday << L'-' << setw(2)
                     << tm_time.tm_hour << setw(2) << tm_time.tm_min << setw(2)
-                    << tm_time.tm_sec << '.' << GetMainThreadPid();
-    const string& time_pid_string = time_pid_stream.str();
+                    << tm_time.tm_sec << L'.' << GetMainThreadPid();
+    const wstring& time_pid_string = time_pid_stream.str();
 
     if (base_filename_selected_) {
       if (!CreateLogfile(time_pid_string)) {
         perror("Could not create log file");
-        fprintf(stderr, "COULD NOT CREATE LOGFILE '%s'!\n",
+        fwprintf(stderr, L"COULD NOT CREATE LOGFILE '%s'!\n",
                 time_pid_string.c_str());
         return;
       }
@@ -1241,13 +1352,15 @@ void LogFileObject::Write(
       stripped_filename = stripped_filename + '.' + hostname + '.' + uidname +
                           ".log." + LogSeverityNames[severity_] + '.';
       // We're going to (potentially) try to put logs in several different dirs
-      const vector<string>& log_dirs = GetLoggingDirectories();
+      const vector<wstring> log_dirs = GetLoggingDirectoriesW();
 
       // Go through the list of dirs, and try to create the log file in each
       // until we succeed or run out of options
       bool success = false;
+      wstring stripped_filename_w =
+          logging::internal::StrConvert<char, wchar_t>(stripped_filename);
       for (const auto& log_dir : log_dirs) {
-        base_filename_ = log_dir + "/" + stripped_filename;
+        base_filename_ = log_dir  + stripped_filename_w;
         if (CreateLogfile(time_pid_string)) {
           success = true;
           break;
@@ -1256,7 +1369,7 @@ void LogFileObject::Write(
       // If we never succeeded, we have to give up
       if (success == false) {
         perror("Could not create logging file");
-        fprintf(stderr, "COULD NOT CREATE A LOGGINGFILE %s!",
+        fwprintf(stderr, L"COULD NOT CREATE A LOGGINGFILE %s!",
                 time_pid_string.c_str());
         return;
       }
@@ -1360,8 +1473,8 @@ void LogCleaner::Enable(const std::chrono::minutes& overdue) {
 void LogCleaner::Disable() { enabled_ = false; }
 
 void LogCleaner::Run(const std::chrono::system_clock::time_point& current_time,
-                     bool base_filename_selected, const string& base_filename,
-                     const string& filename_extension) {
+                     bool base_filename_selected, const wstring& base_filename,
+                     const wstring& filename_extension) {
   assert(enabled_);
   assert(!base_filename_selected || !base_filename.empty());
 
@@ -1375,55 +1488,53 @@ void LogCleaner::Run(const std::chrono::system_clock::time_point& current_time,
       std::chrono::duration_cast<std::chrono::system_clock::duration>(
           std::chrono::duration<int32>{FLAGS_logcleansecs});
 
-  vector<string> dirs;
+  vector<wstring> dirs;
 
   if (!base_filename_selected) {
-    dirs = GetLoggingDirectories();
+    dirs = GetLoggingDirectoriesW();
   } else {
     size_t pos = base_filename.find_last_of(possible_dir_delim, string::npos,
                                             sizeof(possible_dir_delim));
     if (pos != string::npos) {
-      string dir = base_filename.substr(0, pos + 1);
+      wstring dir = base_filename.substr(0, pos + 1);
       dirs.push_back(dir);
     } else {
-      dirs.emplace_back(".");
+      dirs.emplace_back(L".");
     }
   }
 
-  for (const std::string& dir : dirs) {
-    vector<string> logs = GetOverdueLogNames(dir, current_time, base_filename,
+  for (const std::wstring& dir : dirs) {
+    vector<wstring> logs = GetOverdueLogNames(dir, current_time, base_filename,
                                              filename_extension);
-    for (const std::string& log : logs) {
+    for (const std::wstring& log : logs) {
       // NOTE May fail on Windows if the file is still open
-      int result = unlink(log.c_str());
+      int result = details::unlink(log.c_str());
       if (result != 0) {
-        perror(("Could not remove overdue log " + log).c_str());
+        details::perror((L"Could not remove overdue log " + log).c_str());
       }
     }
   }
 }
-
-vector<string> LogCleaner::GetOverdueLogNames(
-    string log_directory,
+vector<std::wstring> LogCleaner::GetOverdueLogNames(
+    const std::wstring &log_directory,
     const std::chrono::system_clock::time_point& current_time,
-    const string& base_filename, const string& filename_extension) const {
+    const std::wstring& base_filename, const std::wstring& filename_extension) const {
   // The names of overdue logs.
-  vector<string> overdue_log_names;
+  vector<std::wstring> overdue_log_names;
 
   // Try to get all files within log_directory.
-  DIR* dir;
-  struct dirent* ent;
+  auto dir = details::opendir(log_directory.c_str());
 
-  if ((dir = opendir(log_directory.c_str()))) {
-    while ((ent = readdir(dir))) {
-      if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) {
+  if (dir) {
+    auto ent = details::readdir(dir);
+    while (ent) {
+      std::wstring filepath = logging::internal::StrConvert(ent->d_name);
+      if (filepath == L"." || filepath == L"..") {
         continue;
       }
 
-      string filepath = ent->d_name;
-      const char* const dir_delim_end =
+      const wchar_t* const dir_delim_end =
           possible_dir_delim + sizeof(possible_dir_delim);
-
       if (!log_directory.empty() &&
           std::find(possible_dir_delim, dir_delim_end,
                     log_directory[log_directory.size() - 1]) != dir_delim_end) {
@@ -1436,25 +1547,25 @@ vector<string> LogCleaner::GetOverdueLogNames(
         overdue_log_names.push_back(filepath);
       }
     }
-    closedir(dir);
+    details::closedir(dir);
   }
 
   return overdue_log_names;
 }
 
 bool LogCleaner::IsLogFromCurrentProject(
-    const string& filepath, const string& base_filename,
-    const string& filename_extension) const {
+    const std::wstring& filepath, const std::wstring& base_filename,
+    const std::wstring& filename_extension) const {
   // We should remove duplicated delimiters from `base_filename`, e.g.,
   // before: "/tmp//<base_filename>.<create_time>.<pid>"
   // after:  "/tmp/<base_filename>.<create_time>.<pid>"
-  string cleaned_base_filename;
+ std::wstring cleaned_base_filename;
 
-  const char* const dir_delim_end =
+  const wchar_t* const dir_delim_end =
       possible_dir_delim + sizeof(possible_dir_delim);
 
   size_t real_filepath_size = filepath.size();
-  for (char c : base_filename) {
+  for (wchar_t c : base_filename) {
     if (cleaned_base_filename.empty()) {
       cleaned_base_filename += c;
     } else if (std::find(possible_dir_delim, dir_delim_end, c) ==
@@ -1478,7 +1589,7 @@ bool LogCleaner::IsLogFromCurrentProject(
       return false;
     }
     // for origin version, `filename_extension` is middle of the `filepath`.
-    string ext = filepath.substr(cleaned_base_filename.size(),
+    std::wstring ext = filepath.substr(cleaned_base_filename.size(),
                                  filename_extension.size());
     if (ext == filename_extension) {
       cleaned_base_filename += filename_extension;
@@ -1497,30 +1608,30 @@ bool LogCleaner::IsLogFromCurrentProject(
   // The characters after `cleaned_base_filename` should match the format:
   // YYYYMMDD-HHMMSS.pid
   for (size_t i = cleaned_base_filename.size(); i < real_filepath_size; i++) {
-    const char& c = filepath[i];
+    const wchar_t& c = filepath[i];
 
     if (i <= cleaned_base_filename.size() + 7) {  // 0 ~ 7 : YYYYMMDD
-      if (c < '0' || c > '9') {
+      if (c < L'0' || c > L'9') {
         return false;
       }
 
     } else if (i == cleaned_base_filename.size() + 8) {  // 8: -
-      if (c != '-') {
+      if (c != L'-') {
         return false;
       }
 
     } else if (i <= cleaned_base_filename.size() + 14) {  // 9 ~ 14: HHMMSS
-      if (c < '0' || c > '9') {
+      if (c < L'0' || c > L'9') {
         return false;
       }
 
     } else if (i == cleaned_base_filename.size() + 15) {  // 15: .
-      if (c != '.') {
+      if (c != L'.') {
         return false;
       }
 
     } else if (i >= cleaned_base_filename.size() + 16) {  // 16+: pid
-      if (c < '0' || c > '9') {
+      if (c < L'0' || c > L'9') {
         return false;
       }
     }
@@ -1530,12 +1641,12 @@ bool LogCleaner::IsLogFromCurrentProject(
 }
 
 bool LogCleaner::IsLogLastModifiedOver(
-    const string& filepath,
+    const std::wstring& filepath,
     const std::chrono::system_clock::time_point& current_time) const {
   // Try to get the last modified time of this file.
-  struct stat file_stat;
+  details::wstat  file_stat;
 
-  if (stat(filepath.c_str(), &file_stat) == 0) {
+  if (details::stat(filepath.c_str(), &file_stat) == 0) {
     const auto last_modified_time =
         std::chrono::system_clock::from_time_t(file_stat.st_mtime);
     const auto diff = current_time - last_modified_time;
@@ -2067,10 +2178,18 @@ void FlushLogFilesUnsafe(LogSeverity min_severity) {
 }
 
 void SetLogDestination(LogSeverity severity, const char* base_filename) {
+  auto w_base_filename = logging::internal::StrConvert<char, wchar_t>(base_filename);
+  SetLogDestination(severity, w_base_filename.c_str());
+}
+void SetLogDestination(LogSeverity severity, const wchar_t* base_filename) {
   LogDestination::SetLogDestination(severity, base_filename);
 }
 
 void SetLogSymlink(LogSeverity severity, const char* symlink_basename) {
+  auto w_symlink_basename = logging::internal::StrConvert<char, wchar_t>(symlink_basename);
+  SetLogSymlink(severity, w_symlink_basename.c_str());
+}
+void SetLogSymlink(LogSeverity severity, const wchar_t* symlink_basename) {
   LogDestination::SetLogSymlink(severity, symlink_basename);
 }
 
@@ -2141,8 +2260,11 @@ void AddLogSink(LogSink* destination) {
 void RemoveLogSink(LogSink* destination) {
   LogDestination::RemoveLogSink(destination);
 }
-
-void SetLogFilenameExtension(const char* ext) {
+void SetLogFilenameExtension(const char* filename_extension) {
+  auto w_extension = logging::internal::StrConvert<char, wchar_t>(filename_extension);
+  SetLogFilenameExtension(w_extension.c_str());
+}
+void SetLogFilenameExtension(const wchar_t* ext) {
   LogDestination::SetLogFilenameExtension(ext);
 }
 
@@ -2338,44 +2460,43 @@ bool SendEmail(const char* dest, const char* subject, const char* body) {
   return SendEmailInternal(dest, subject, body, true);
 }
 
-static void GetTempDirectories(vector<string>& list) {
+static void GetTempDirectories(vector<wstring>& list) {
   list.clear();
 #ifdef GLOG_OS_WINDOWS
   // On windows we'll try to find a directory in this order:
   //   C:/Documents & Settings/whomever/TEMP (or whatever GetTempPath() is)
   //   C:/TMP/
   //   C:/TEMP/
-  char tmp[MAX_PATH];
-  if (GetTempPathA(MAX_PATH, tmp)) list.push_back(tmp);
-  list.push_back("C:\\TMP\\");
-  list.push_back("C:\\TEMP\\");
+  wchar_t tmp[MAX_PATH];
+  if (GetTempPathW(MAX_PATH, tmp)) list.push_back(tmp);
+  list.push_back(L"C:\\TMP\\");
+  list.push_back(L"C:\\TEMP\\");
 #else
   // Directories, in order of preference. If we find a dir that
   // exists, we stop adding other less-preferred dirs
-  const char* candidates[] = {
+  const std::wstring candidates[] = {
       // Non-null only during unittest/regtest
-      getenv("TEST_TMPDIR"),
+      google::logging::internal::getenv(L"TEST_TMPDIR"),
 
       // Explicitly-supplied temp dirs
-      getenv("TMPDIR"),
-      getenv("TMP"),
+      google::logging::internal::getenv(L"TMPDIR"),
+      google::logging::internal::getenv(L"TMP"),
 
       // If all else fails
-      "/tmp",
+      L"/tmp",
   };
 
-  for (auto d : candidates) {
-    if (!d) continue;  // Empty env var
+  for (auto dstr : candidates) {
+    if (dstr.empty()) continue;  // Empty env var
 
     // Make sure we don't surprise anyone who's expecting a '/'
-    string dstr = d;
-    if (dstr[dstr.size() - 1] != '/') {
-      dstr += "/";
+    if (dstr[dstr.size() - 1] != L'/') {
+      dstr += L"/";
     }
     list.push_back(dstr);
 
-    struct stat statbuf;
-    if (!stat(d, &statbuf) && S_ISDIR(statbuf.st_mode)) {
+    details::wstat statbuf;
+    if (!details::stat(dstr.c_str(), &statbuf) && S_ISDIR(statbuf.st_mode)) {
       // We found a dir that exists - we're done.
       return;
     }
@@ -2383,48 +2504,65 @@ static void GetTempDirectories(vector<string>& list) {
 #endif
 }
 
-static std::unique_ptr<std::vector<std::string>> logging_directories_list;
-
-const vector<string>& GetLoggingDirectories() {
+static std::unique_ptr<std::vector<std::wstring>> logging_directories_list;
+const vector<wstring>& GetLoggingDirectoriesW(const std::wstring &log_dir) {
   // Not strictly thread-safe but we're called early in InitGoogle().
   if (logging_directories_list == nullptr) {
-    logging_directories_list = std::make_unique<std::vector<std::string>>();
+    logging_directories_list = std::make_unique<std::vector<std::wstring>>();
 
-    if (!FLAGS_log_dir.empty()) {
+    if (!log_dir.empty()) {
       // Ensure the specified path ends with a directory delimiter.
       if (std::find(std::begin(possible_dir_delim),
                     std::end(possible_dir_delim),
-                    FLAGS_log_dir.back()) == std::end(possible_dir_delim)) {
-        logging_directories_list->push_back(FLAGS_log_dir + "/");
+                    log_dir.back()) == std::end(possible_dir_delim)) {
+        logging_directories_list->push_back(log_dir + L"/");
       } else {
-        logging_directories_list->push_back(FLAGS_log_dir);
+        logging_directories_list->push_back(log_dir);
       }
     } else {
       GetTempDirectories(*logging_directories_list);
 #ifdef GLOG_OS_WINDOWS
-      char tmp[MAX_PATH];
-      if (GetWindowsDirectoryA(tmp, MAX_PATH))
+      wchar_t tmp[MAX_PATH];
+      if (GetWindowsDirectoryW(tmp, MAX_PATH))
         logging_directories_list->push_back(tmp);
-      logging_directories_list->push_back(".\\");
+      logging_directories_list->push_back(L".\\");
 #else
-      logging_directories_list->push_back("./");
+      logging_directories_list->push_back(L"./");
 #endif
     }
   }
   return *logging_directories_list;
 }
 
+
+const vector<string> GetLoggingDirectories() {
+  auto wdirs = GetLoggingDirectoriesW();
+  vector<string> dirs;
+  for (const auto wdir : wdirs) {
+    dirs.push_back(logging::internal::StrConvert<wchar_t, char>(wdir));
+  }
+  return dirs;
+}
+
+const vector<wstring>& GetLoggingDirectoriesW() {
+  if (!FLAGS_log_wdir.empty()) {
+    return GetLoggingDirectoriesW(FLAGS_log_wdir);
+  } else {
+    return GetLoggingDirectoriesW(logging::internal::StrConvert<char, wchar_t>(FLAGS_log_dir));
+  }
+}
+
 // Returns a set of existing temporary directories, which will be a
 // subset of the directories returned by GetLoggingDirectories().
 // Thread-safe.
 GLOG_NO_EXPORT
-void GetExistingTempDirectories(vector<string>& list) {
+void GetExistingTempDirectories(vector<wstring>& list) {
   GetTempDirectories(list);
   auto i_dir = list.begin();
   while (i_dir != list.end()) {
     // zero arg to access means test for existence; no constant
     // defined on windows
-    if (access(i_dir->c_str(), 0)) {
+    if (details::access(i_dir->c_str(), 0)) {
       i_dir = list.erase(i_dir);
     } else {
       ++i_dir;
diff --git a/src/utilities.h b/src/utilities.h
index 581bff7f5..f31a5be87 100644
--- a/src/utilities.h
+++ b/src/utilities.h
@@ -41,6 +41,7 @@
 #include <string>
 #include <type_traits>
 #include <utility>
+#include <stdlib.h>
 
 // printf macros for size_t, in the style of inttypes.h
 #ifdef _LP64
@@ -125,6 +126,59 @@ struct CrashReason {
   int depth{0};
 };
 
+
+static size_t CharConvert(wchar_t* dst, const char* src, size_t n) {
+return mbstowcs(dst, src, n);
+}
+
+static size_t CharConvert(char* dst, const wchar_t* src, size_t n) {
+return wcstombs(dst, src, n);
+}
+
+template <class ChSrc, class ChDst>
+std::basic_string<ChDst> StrConvert(const std::basic_string<ChSrc>& src)
+{
+  auto converted_size = CharConvert(nullptr, src.c_str(), 0);
+  if (converted_size == (size_t)-1) {
+    return {};
+  }
+  std::basic_string<ChDst> dst(converted_size + 1, {});
+  converted_size = CharConvert(&dst[0], src.c_str(), converted_size + 1);
+  if (converted_size == (size_t)-1) {
+    return {};
+  }
+  return dst.substr(0, dst.size() - 1);
+}
+
+static std::basic_string<wchar_t> StrConvert(const wchar_t *src) {
+  return src;
+}
+static std::basic_string<wchar_t> StrConvert(const char* src) {
+  return StrConvert<char, wchar_t>(std::basic_string<char>(src));
+}
+
+static std::string getenv(const char * name)
+{
+  auto val = ::getenv(name);
+  if(val != nullptr && val[0] != '\0') {
+    return val;
+  }
+  return {};
+}
+static std::wstring getenv(const wchar_t* name) {
+#ifdef GLOG_OS_WINDOWS
+  auto val = ::_wgetenv(name);
+  if(val != nullptr && val[0] != '\0') {
+    return val;
+  }
+  return {};
+#else
+  auto str_name = StrConvert<wchar_t, char>(name);
+  auto str_val = getenv(str_name.c_str());
+  return StrConvert<char, wchar_t>(str_val);
+#endif  //  GLOG_OS_WINDOWS
+}
+
 }  // namespace internal
 }  // namespace logging
 

From 46742e2ea28eef1ecc5b46ad23fb224cd3440c6a Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sat, 27 Jan 2024 17:40:16 +0800
Subject: [PATCH 2/9] feat: add to include header

---
 src/base/commandlineflags.h | 2 +-
 src/flags.cc                | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h
index f7bd5ac2c..4375f52ad 100644
--- a/src/base/commandlineflags.h
+++ b/src/base/commandlineflags.h
@@ -53,6 +53,7 @@
 #include <string>
 
 #include "config.h"
+#include "utilities.h"
 
 #ifdef GLOG_USE_GFLAGS
 
@@ -61,7 +62,6 @@
 #else
 
 #include "glog/logging.h"
-#include "utilities.h"
 
 #  define DECLARE_VARIABLE(type, shorttype, name, tn) \
     namespace fL##shorttype {                         \
diff --git a/src/flags.cc b/src/flags.cc
index ca4a4766a..016c6f967 100644
--- a/src/flags.cc
+++ b/src/flags.cc
@@ -35,7 +35,7 @@
 #include <array>
 #include "base/commandlineflags.h"
 #include "glog/log_severity.h"
-
+#include "utilities.h"
 namespace {
 
 // Compute the default value for --log_dir

From ff7fbeda683b9ab41b4f8ca7edd2be9e1eacf86f Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sat, 27 Jan 2024 17:43:52 +0800
Subject: [PATCH 3/9] fix: adjust header

---
 src/base/commandlineflags.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h
index 4375f52ad..b4929688b 100644
--- a/src/base/commandlineflags.h
+++ b/src/base/commandlineflags.h
@@ -53,7 +53,7 @@
 #include <string>
 
 #include "config.h"
-#include "utilities.h"
+#include "../utilities.h"
 
 #ifdef GLOG_USE_GFLAGS
 

From 03d39e553fa4608865c75b8b241efd2aacec8c19 Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sat, 27 Jan 2024 21:32:31 +0800
Subject: [PATCH 4/9] feat: adjust format

---
 src/base/commandlineflags.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h
index b4929688b..e38463172 100644
--- a/src/base/commandlineflags.h
+++ b/src/base/commandlineflags.h
@@ -117,10 +117,11 @@
     namespace fLS {                                                     \
         std::wstring FLAGS_##name##_buf(value);                         \
         GLOG_EXPORT std::wstring& FLAGS_##name = FLAGS_##name##_buf;    \
-        wchar_t FLAGS_no##name;                                         \
+        wchar_t FLAGS_no##name;                                      \
     }                                                                   \
-    using fLS::FLAGS_##name     
-#endif  // GLOG_USE_GFLAGS
+    using fLS::FLAGS_##name      
+
+#   endif  // GLOG_USE_GFLAGS
 
 // Define GLOG_DEFINE_* using DEFINE_* . By using these macros, we
 // have GLOG_* environ variables even if we have gflags installed.

From e0fbb6dd1d7cd68f6df5100c769045f086c1da1b Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sat, 27 Jan 2024 21:35:12 +0800
Subject: [PATCH 5/9] =?UTF-8?q?fix=EF=BC=9Ause=20default=20value?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/flags.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/flags.cc b/src/flags.cc
index 016c6f967..83a600792 100644
--- a/src/flags.cc
+++ b/src/flags.cc
@@ -152,7 +152,7 @@ GLOG_DEFINE_string(
     "of the default logging directory.");
 
 GLOG_DEFINE_wstring(
-    log_wdir, DefaultLogDir<wchar_t>(),
+    log_wdir, L"",
     L"If specified, logfiles are written into this directory instead "
     L"of the default logging directory.");
 

From 721bcf445e77ebf9520f0ebac474237ff368ee5d Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sun, 28 Jan 2024 00:14:40 +0800
Subject: [PATCH 6/9] fix: build error

---
 src/flags.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/flags.cc b/src/flags.cc
index 83a600792..e96ab3f08 100644
--- a/src/flags.cc
+++ b/src/flags.cc
@@ -152,9 +152,9 @@ GLOG_DEFINE_string(
     "of the default logging directory.");
 
 GLOG_DEFINE_wstring(
-    log_wdir, L"",
+    log_wdir, DefaultLogDir<wchar_t>(),
     L"If specified, logfiles are written into this directory instead "
-    L"of the default logging directory.");
+    "of the default logging directory.");
 
 GLOG_DEFINE_string(log_link, "",
                    "Put additional links to the log "

From 52ef9d86cc912e18f2a968e13704dad026abf70e Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sun, 28 Jan 2024 00:48:19 +0800
Subject: [PATCH 7/9] fix: build error

---
 src/flags.cc | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/flags.cc b/src/flags.cc
index e96ab3f08..c86ff2078 100644
--- a/src/flags.cc
+++ b/src/flags.cc
@@ -152,9 +152,8 @@ GLOG_DEFINE_string(
     "of the default logging directory.");
 
 GLOG_DEFINE_wstring(
-    log_wdir, DefaultLogDir<wchar_t>(),
-    L"If specified, logfiles are written into this directory instead "
-    "of the default logging directory.");
+    log_wdir, L"",
+    L"If specified, logfiles are written into this directory instead f the default logging directory.");
 
 GLOG_DEFINE_string(log_link, "",
                    "Put additional links to the log "

From 226e2d682b6fd32b4edaf362f51079acca688a98 Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sun, 28 Jan 2024 00:59:13 +0800
Subject: [PATCH 8/9] fix: build error

---
 src/base/commandlineflags.h | 4 ++--
 src/glog/flags.h            | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h
index e38463172..07c45a833 100644
--- a/src/base/commandlineflags.h
+++ b/src/base/commandlineflags.h
@@ -108,12 +108,12 @@
     }                                                           \
     using fLS::FLAGS_##name
 
-#define DECLARE_wstring(name)                       \
+#  define DECLARE_wstring(name)                       \
   namespace fLS {                                   \
   extern GLOG_EXPORT std::wstring& FLAGS_##name;    \
   }                                                 \
   using fLS::FLAGS_##name
-#define DEFINE_wstring(name, value, meaning)                            \
+#   define DEFINE_wstring(name, value, meaning)                            \
     namespace fLS {                                                     \
         std::wstring FLAGS_##name##_buf(value);                         \
         GLOG_EXPORT std::wstring& FLAGS_##name = FLAGS_##name##_buf;    \
diff --git a/src/glog/flags.h b/src/glog/flags.h
index 92ea1ce93..170ca0c17 100644
--- a/src/glog/flags.h
+++ b/src/glog/flags.h
@@ -106,7 +106,7 @@
     }                                             \
     using fLS::FLAGS_##name
 
-#define DECLARE_wstring(name)                    \
+#  define DECLARE_wstring(name)                  \
   namespace fLS {                                \
   extern GLOG_EXPORT std::wstring& FLAGS_##name; \
   }                                              \

From 40c4088a6e80265be5f9a2e47e352731540979b0 Mon Sep 17 00:00:00 2001
From: xfc1939 <xfc1939@gmail.com>
Date: Sun, 28 Jan 2024 01:01:01 +0800
Subject: [PATCH 9/9] fix: build error

---
 src/base/commandlineflags.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h
index 07c45a833..67bce1d89 100644
--- a/src/base/commandlineflags.h
+++ b/src/base/commandlineflags.h
@@ -143,7 +143,7 @@
   DEFINE_string(name, EnvToString("GLOG_" #name, value), meaning)
 
 #define GLOG_DEFINE_wstring(name, value, meaning) \
-  DEFINE_wstring(name, EnvToString(L"GLOG_" #name, value), meaning)
+  DEFINE_wstring(name, EnvToString(L"GLOG_", value), meaning)
 
 
 // These macros (could be functions, but I don't want to bother with a .cc