Fix installer download when temp. path is not set

[mere-human]

Use a fallback TMP or TEMP and then use the current directory.

Fix #16

[mere-human]

How to check it without harming the local machine environment?
Just unset any of the variables in debugger. Project > Properties:

[mere-human]

@donho I think this is pretty important to fix because:

1. Absence of TEMP leads to crash which is not a good user experience.
2. Using _wgetenv may lead to a security problem.

https://stackoverflow.com/questions/48568707/getenv-function-may-be-unsafe-really

[donho]

@mere-human

How to check it without harming the local machine environment?
Just unset any of the variables in debugger. Project > Properties:

It's good. But I need a real crash to validate this PR.
Removing both TMP & TEMP doesn't make GUP crash, and GUP updates Notepad++ with no problem.

[mere-human]

But I need a real crash to validate this PR.

@donho ok, try this:

• open a terminal (cmd)
• navigate to Notepad++ directory
• change environment variables only for current terminal as following
• run set TMP=
• run set TEMP=
• now run notepad++.exe or gup.exe

[mere-human]

Or this:
https://stackoverflow.com/questions/13222724/command-line-to-remove-an-environment-variable-from-the-os-level-configuration

But be careful!

[donho]

Find a suitable solution for Notepad++ installed in Program Files.

[mere-human]

@donho Do you consider merging this before RC?

[jurekl]

@donho

It's good. But I need a real crash to validate this PR.
Removing both TMP & TEMP doesn't make GUP crash, and GUP updates Notepad++ with no problem.

I am providing a link to my specification of the error description #16 (comment)

[donho]

Remove the unnecessary function. Don't copy the file into the root of user space and take consideration of empty string to terminate gracefully. Do it as simple as possible.

[donho]

@mere-human
I'm doing RC2, and I'm wondering if you wanna add %UserProfile%\Downloads in this PR.
If yes, could it be done asap? Otherwise we can always update GUP in the next next release, or RC3 (if any).

[mere-human]

I'm doing RC2, and I'm wondering if you wanna add %UserProfile%\Downloads in this PR.
If yes, could it be done asap?

@donho
I can do it later today (in ~4 hours) since I need to do some testing.
If it's too late, then proceed with submitting this PR and I can add the Downloads folder handling in a separate PR.

[donho]

If it's too late, then proceed with submitting this PR and I can add the Downloads folder handling in a separate PR.

Please do it in the same PR.
RC2 is already available, so let's integrate the new GUP in the 8.1.6 release.

[mere-human]

Verified on Windows 10 and on Windows 7.
Here's a result of running an installer from terminal without TMP, TEMP and AppData:

[donho]

ARM64 build error:

[donho]

Use Win32 API instead of COM, or remove the following part completely.

	LPWSTR path = nullptr;
	const HRESULT hr = ::SHGetKnownFolderPath(FOLDERID_Downloads, 0, nullptr, &path);
	if (SUCCEEDED(hr))
	{
		std::wstring result = path;
		CoTaskMemFree(path);
		return result;
	}

[mere-human]

ARM64 build error:

Sorry, I forgot about ARM64 build.
That's why WinGUP needs this #17
I'll fix it.

[mere-human]

Shall we remove ARM mentions from the .vcxproj file? It seems it was added by mistake
https://github.com/notepad-plus-plus/wingup/blob/master/vcproj/GUP.vcxproj#L57

[donho]

@mere-human

The request is quite clear:

Use Win32 API instead of COM, or remove the following part completely.

	LPWSTR path = nullptr;
	const HRESULT hr = ::SHGetKnownFolderPath(FOLDERID_Downloads, 0, nullptr, &path);
	if (SUCCEEDED(hr))
	{
		std::wstring result = path;
		CoTaskMemFree(path);
		return result;
	}

I don't want COM in WinGup project.

[mere-human]

I don't want COM in WinGup project.

It's already in x64 build.
Ok, I can remove this part.
Or compile it for x64 but not for ARM64.

[donho]

Shall we remove ARM mentions from the .vcxproj file? It seems it was added by mistake
https://github.com/notepad-plus-plus/wingup/blob/master/vcproj/GUP.vcxproj#L57

Leave it please.
I will take care of it myself if needed.

[donho]

Don't modify project file.

[donho]

Thank you @mere-human