Merge bitcoin#18: Use utf-8 to decode filename

f8e797a Use utf-8 to decode filename (Chun Kuan Lee)

Pull request description:

  See bitcoin#13869

  Enable unicode support for leveldb on Windows

  CI result for applying this change is available in bitcoin#13787

Tree-SHA512: 860261f973ec7aec8d3051632be8154d87854df8a604ef10b9171701f132c4ba9855ca97fc6e2d529ba322a8100e1e160d5d0f2afe558158bde89979815b5246

util/env_win.cc

@@ -203,24 +203,16 @@ class Win32Env : public Env
 
 void ToWidePath(const std::string& value, std::wstring& target) {
 	wchar_t buffer[MAX_PATH];
-	MultiByteToWideChar(CP_ACP, 0, value.c_str(), -1, buffer, MAX_PATH);
+	MultiByteToWideChar(CP_UTF8, 0, value.c_str(), -1, buffer, MAX_PATH);
 	target = buffer;
 }
 
 void ToNarrowPath(const std::wstring& value, std::string& target) {
 	char buffer[MAX_PATH];
-	WideCharToMultiByte(CP_ACP, 0, value.c_str(), -1, buffer, MAX_PATH, NULL, NULL);
+	WideCharToMultiByte(CP_UTF8, 0, value.c_str(), -1, buffer, MAX_PATH, NULL, NULL);
 	target = buffer;
 }
 
-std::string GetCurrentDir()
-{
-    CHAR path[MAX_PATH];
-    ::GetModuleFileNameA(::GetModuleHandleA(NULL),path,MAX_PATH);
-    *strrchr(path,'\\') = 0;
-    return std::string(path);
-}
-
 std::wstring GetCurrentDirW()
 {
     WCHAR path[MAX_PATH];
@@ -229,6 +221,13 @@ std::wstring GetCurrentDirW()
     return std::wstring(path);
 }
 
+std::string GetCurrentDir()
+{
+    std::string path;
+    ToNarrowPath(GetCurrentDirW(), path);
+    return path;
+}
+
 std::string& ModifyPath(std::string& path)
 {
     if(path[0] == '/' || path[0] == '\\'){