Add support for wchar_t on Windows

[Kentzo]

No description provided.

[gabime]

Thanks for the pull. Two problems:
1.the build fails in travis
2. I dont want to impose wchar on windows. It should be configurable

[Kentzo]

1. We will fix that, @a-martynovich Please take a look.
2. Do you have some concept in mind to make it configurable?

[gabime]

Not sure. Maybe simple ifdef will do. Most of them are defined in tweakme.h

[Kentzo]

@gabime Could you put some explanation behind making it configurable? The majority of windows desktop applications will use wchar_t (either right away or after they realize their app crash for a lot of users).

[gabime]

@Kentzo add '''#define use_whcar''' to tweakme.h

[gabime]

Seems the tests fails because it gets filesize of 2048 but expects 1024.. Makes sense for wchar

[a-martynovich]

@gabime Fixed, please take a look.

[gabime]

Thanks. Looks good.
Please remove the use ofSPDLOG_NO_WCHAR from the code -It is redundant
#define SPDLOG_USE_WCHAR is enough (and should commented out by default in tweakme.h)

[Kentzo]

@gabime Done but tests failed. Not sure if it's due to our changes.

[gabime]

I reverted this - it causes problems - global defines that conflicts with use code. We need to find a cleaner solution. Maybe a dedicated file sink

[Kentzo]

Current version is completely unusable without that change on Windows (except developer's environment I guess)...

Do you have a set of changes in mind to be made?

[Kentzo]

@gabime I'm willing to contribute so we can use spdlog's upstream in our product. Please think of steps this change requires to make it happen.

[gabime]

Main issue was that it broke user code because it introdeced global defines..

[Kentzo]

@gabime We could use templates

[gabime]

Another option would be defining a new sink class which supports wchar. This would be the less intrusive option i think.

[VikingExplorer]

What's the status of this? I'm getting

        auto log = spdlog::get( "debug" );
        log->debug( fmt.value().c_str(), value1 );
        auto msg = fmt::format( fmt.value(), value1 );

1>Log.cpp(75): error C2664: 'spdlog::details::line_logger spdlog::logger::debug<wchar_t>(const char *,const wchar_t &)': cannot convert argument 1 from 'const wchar_t *' to 'const char *'

I have already integrated with CppFormat, so I know it supports wchar_t.

What am I doing wrong? I searched the code for SPDLOG_USE_WCHAR and couldn't find it.

[Kentzo]

@VikingExplorer Change was reverted in the mainstream. We're using our fork for know. Feel free to improve this PR.

[Kentzo]

@gabime Is it all right to have the SPDLOG_USE_WCHAR macro though?

[Kentzo]

I don't think supporting 2 sink is a good solution: you would end up with 2 identical version of the code… Maybe I put the S macro under the SPDLOG_ namespace?

[gabime]

I don't know.. The code got quite ugly with all those "tstrings" everywhere.. Not sure it worth it

[Kentzo]

@gabime I tried to do it with templates, it becomes even uglier: you cannot easily get around with char and wchar_t string literals.

Current implementation is terribly unusable on Windows though: you cannot have a path with Chinese symbols for example.

[Kentzo]

@gabime Made another PR that attempts to solve this problem.

[gabime]

@Kentzo it fails the tests. included file not found..

[Kentzo]

@gabime Fixed.