Turns out I mistook @celticminstrel's opinion that we should use include guards over pragma (737916e).
Since all major compilers support `#pragma once`, there's no reason not to use it.
For future mergability reasons, this excludes src/spirit_po and src/xBRZ. It also excludes src/boost-patched.
This makes it so we no longer try to steal the console back to a log
file when using --wconsole with the new redirection code. Now the
--wconsole switch triggers a special mode of the log file manager that
uses a native console instead of log files.
As a necessary bonus to appease compilers, the GUI2 version info dialog
now uses the correct log file path when not started with the --wconsole
switch. Yay!
This replaces SDL 1.2's built-in stdout/stderr redirection, which writes
the log file to the process working directory (usually an
admin-restricted location) instead of a more accessible user-writable
location.
My approach combines stdout and stderr into a single log file which
includes the process id and timestamp in its filename in order to
accomodate multiple instances and (coming later) log rotation. The log
file is created in the user's temporary directory defined by Windows,
and then relocated to the game user data dir as soon as it is set-up the
first time, placed in the Windows-specific logs/ subdir.
The most pressing issues this solves are the lack of built-in
stdout/stderr redirection in SDL 2's SDL2main.lib entry point, and
Unicode path issues with SDL 1.2 (bug #22897). Additionally, it allows
us to not have to rely on UAC virtualization anymore; this is arguably
far more important because it has been known to break on occasion (e.g.
<http://r.wesnoth.org/t42970>), and starting with version 1.13.2 we want
to declare Windows Vista - 10 compatibility in our side-by-side manifest
(see commit e119f4071f).
Currently missing features coming later:
* Log rotation (otherwise the logs/ dir may grow forever)
* wesnothd support (although the code is already required to be linked
into wesnothd due to it being required by the FS API)
* Integration with the version info dialog