Galadrim
As I have seen, SDL implements its own command line parser for Windows in SDL_windows_main.c. Unfortunately, it doesn't seem to allow command line arguments with trailing backslashes if quoting is required.
Usually, when you write an application that gets command line arguments passed as argc and argv, the parsing is done by parse_cmdline. The Windows API also provides the function CommandLineToArgvW, so an application can parse itself if only the command line string is provided. Both functions behave almost identically according to their documentation. If the argument "\\" (including the quotes) is passed, they both turn it into a single backslash.
The SDL command line parser on the other hand doesn't recognize the second quote character as the closing character in this example and therefore includes it in the parsed argument. The parser does not count the number of backslashes preceding a quote. It always treats a quote as escaped if a backslash is in front of it. Therefore, it should be impossible to quote and escape an argument correctly, if it has a trailing backslash and contains characters that require quoting.
Of course, each application is allowed to implement its own parsing rules, so SDL is free to do so. But the problem I see is that there are arguments, that are impossible to be passed to the parser correctly, as I described above. Is there a reason, why SDL does not simply use CommandLineToArgvW instead of implementing its own parser?
Here are some links that show that correct argument parsing, as it is usually done in Windows, is quite complicated:
https://docs.microsoft.com/en-us/windows/desktop/api/shellapi/nf-shellapi-commandlinetoargvwhttp://www.windowsinspired.com/how-a-windows-programs-splits-its-command-line-into-individual-arguments/
Otherwise, we are using the allocator before the app can set up its own hooks.
Now we use VirtualAlloc, and WideCharToMultiByte (because SDL_iconv uses
SDL_malloc, too!) to get ready to call into SDL_main.
This also makes console_wmain() call into the same routines as everything
else, so we don't have to deal with those allocations, too. Hopefully we
end up with the same results from GetCommandLine() as we do in wargv.
Fixes Bugzilla #4340.
Simon Hug
There are currently three entry points in the SDL2_main code for windows: main, wmain and WinMain. Only the latter two properly convert the arguments to UTF-8.
Console applications linked with MSVC will always link with the main entry point (wmain has to be selected by manually setting the entry point). This makes it likely that such programs will not have proper unicode arguments.
Simon Hug
The SDLmain file src/main/windows/SDL_windows_main.c defines both entry points for console applications, main and wmain. This seems to confuse MSVC. It outputs a LNK4067 warning and then chooses main, which is a shame because only wmain has the unicode handling. Using SDLmain.lib provided on libsdl.org, the linker also goes for main.
I'm proposing to not define the main entry point at all. wmain should be supported well enough with MSVC.
Simon Hug
The function console_wmain in src/main/windows/SDL_windows_main.c does not null terminate the argument list it is creating. As specified by the C standard, "argv[argc] shall be a null pointer."
The SDLTest framework makes use of that null pointer and some test programs can cause an access violation because it's missing.
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
