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Re: More Unicode questions [message #21535 is a reply to message #21483]

Mon, 25 May 2009 12:49

cbpporter
Messages: 1427
Registered: September 2007

Ultimate Contributor

I started my hunting down of invalid uses of ANSI API on Unicode Windows.

I started with the part that gets the environment variables, namely AppInitEnvironment__. This uses ANSI versions, so even through my environment variables are kept by windows in Unicode, any non Latin characters would be lost in U++ applications. Following the normal procedure, I would test with IsWinNT and duplicate the code, but this time using wchar and W version of the API. Simple enough in theory.

Unfortunately I have bitten of more than I can chew. It seems that even GetEnvironmentStringsW isn't capable of returning Unicode strings. Even worse, result vary a lot depending on system locale, but even a string entered with characters from that locale won't be returned correctly, with '?' characters replacing non Latin ones, but not all of them. I have tried all other Win API functions to retrieve the variables, and the result is the same.

There is only one place where the values are correct: the Windows registry. I've written a test version that in my tests retrieves correctly environment variables with all possible of characters used.

If anybody has time and patience for a short experiment, then please try to create a environment variable with some national characters, or any Unicode character and see if the following code retrieves the correct values:

WString GetWinRegStringW(const wchar *value, const wchar *path, HKEY base_key) {
	HKEY key = 0;
	if(RegOpenKeyExW(base_key, path, 0, KEY_READ, &key) != ERROR_SUCCESS)
		return WString::GetVoid();
	dword type, data;
	if(RegQueryValueExW(key, value, 0, &type, NULL, &data) != ERROR_SUCCESS)
	{
		RegCloseKey(key);
		return WString::GetVoid();
	}
	WStringBuffer raw_data(data);
	if(RegQueryValueExW(key, value, 0, 0, (byte *)~raw_data, &data) != ERROR_SUCCESS)
	{
		RegCloseKey(key);
		return WString::GetVoid();
	}
	if(data > 0 && (type == REG_SZ || type == REG_EXPAND_SZ))
		data -= 2;
	raw_data.SetLength(data / 2);
	RegCloseKey(key);
	return raw_data;
}

void Win32GetEnvVars()
{
#ifndef PLATFORM_WINCE
	//FileOut f("c:\\test.log");
	if (IsWin2K()) {
		wchar *env = GetEnvironmentStringsW();
		for(wchar *ptr = env; *ptr; ptr++)
		{
			const wchar *b = ptr;
			if(*ptr)
				ptr++;
			while(*ptr && *ptr != '=')
				ptr++;
			WString varname(b, ptr);
			
			if(*ptr)
				ptr++;
			b = ptr;
			while(*ptr)
				ptr++;
			WString value = WString(b, ptr);
			
			WString newval = GetWinRegStringW(varname, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager\\Environment", HKEY_LOCAL_MACHINE);
			if (!newval.IsVoid()) 
				value = newval;
			
			newval = GetWinRegStringW(varname, L"Environment", HKEY_CURRENT_USER);
			if (!newval.IsVoid()) 
				value = newval;
			
			/*WString temp = (varname + "=" + value);
			WString nl = L"\r\n";
			f.PutW(temp, temp.GetCount());
			f.PutW(nl, 2);*/
						
			coreEnvPtr__().GetAdd(ToUpper(varname).ToString()) = value.ToString();
		}
		FreeEnvironmentStringsW(env);
	}
	else {
		char *env = GetEnvironmentStringsA();
		for(char *ptr = env; *ptr; ptr++)
		{
			const char *b = ptr;
			if(*ptr)
				ptr++;
			while(*ptr && *ptr != '=')
				ptr++;
			String varname(b, ptr);
			
			if(*ptr)
				ptr++;
			b = ptr;
			while(*ptr)
				ptr++;
			coreEnvPtr__().GetAdd(ToUpper(varname)) = FromSystemCharset(String(b, ptr));
		}
		FreeEnvironmentStringsA(env);
	}
	//f.Close();
#endif
}

void AppInitEnvironment__() {
	Win32GetEnvVars();
	CommonInit();
}

The code replaces AppInitEnvironment__ in Core/App.cpp.

Thank you!

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