Instead of using %windir%\Temp, which is not accessible by default and
contains a lot of unrelated files, as the location for our log files,
this commit moves it to %ProgramData%\Looking Glass (host), which will
be a dedicated directory just for the LG host log files. This applies
to both the host application logs and the service logs.
Also, we now switched to using PathCombineA from shlwapi.dll instead
of using snprintf, which greatly simplifies the code. PathCombineA
guarantees that the path would not overflow a buffer of MAX_PATH.
This makes it a compile-time error to call a function that semantically
takes no parameters with a nonzero number of arguments.
Previously, such code would still compile, but risk blowing up the stack
if a compiler chose to use something other than caller-cleanup calling
conventions.
Now that it's recommended to run LG as the `SYSTEM` user, launching an
application to read the log file is dangerous as it will be launched
with the same access rights (`SYSTEM`). Instead so as Microsoft
recommends and only present a message box with the information.
Experimental, use at your own peril!
This commit adds the ability for the LG host to install and launch with
Windows as a system service.
To install simply run `looking-glass-host.exe InstallService` or
conversely to uninstall `looking-glass-host.exe UninstallService`.