Link statically on Windows

Try to link statically as much as possible on Windows, to reduce the
number of DLLs that have to be shipped with Windows builds.

Also document the build process on Windows.

README.md

@@ -47,6 +47,36 @@ Finally install it to your system (optional),
 
     ninja -C build install
 
+### Windows
+
+xsystem4 can be built on Windows using MSYS2.
+
+First install MSYS2, and then open the MINGW64 shell and run the following command,
+
+    pacman -S flex bison \
+        mingw-w64-x86_64-gcc \
+        mingw-w64-x86_64-meson \
+        mingw-w64-x86_64-pkg-config \
+        mingw-w64-x86_64-SDL2 \
+        mingw-w64-x86_64-freetype \
+        mingw-w64-x86_64-libjpeg-turbo \
+        mingw-w64-x86_64-libwebp \
+        mingw-w64-x86_64-libsndfile \
+        mingw-w64-x86_64-glew
+
+Then build the xsystem4 executable with meson,
+
+    mkdir build
+    meson build
+    ninja -C build
+
+To create a portable executable, it is neccessary to copy some DLLs into the same directory as xsystem4.exe.
+You can determine the required DLLs with the following command,
+
+    ldd build/src/xsystem4.exe | grep mingw64
+
+The `fonts` and `shaders` directories must also be shipped together with xsystem4.exe.
+
 Installing
 ----------
 

meson.build

@@ -3,16 +3,21 @@ project('system4', 'c',
 add_project_arguments('-D_DEFAULT_SOURCE', language : 'c')
 add_project_arguments('-DXSYS4_DATA_DIR="' + get_option('prefix') / get_option('datadir') / 'xsystem4"', language : 'c')
 
-zlib = dependency('zlib')
+static_libs = false
+if host_machine.system() == 'windows'
+    static_libs = true
+endif
+
+zlib = dependency('zlib', static : static_libs)
 libm = meson.get_compiler('c').find_library('m', required: false)
-sdl2 = dependency('sdl2')
-ft2 = dependency('freetype2')
-ffi = dependency('libffi')
-tj = dependency('libturbojpeg')
-webp = dependency('libwebp')
-png = dependency('libpng')
+sdl2 = dependency('sdl2', static : static_libs)
+ft2 = dependency('freetype2', static : static_libs)
+ffi = dependency('libffi', static : static_libs)
+tj = dependency('libturbojpeg', static : static_libs)
+webp = dependency('libwebp', static : static_libs)
+png = dependency('libpng', static : static_libs)
 cglm = dependency('cglm', fallback : ['cglm', 'cglm_dep'])
-sndfile = dependency('sndfile')
+sndfile = dependency('sndfile', static : static_libs)
 
 gles = dependency('glesv2', version : '>=3', required: get_option('opengles'))
 if gles.found()
@@ -24,8 +29,8 @@ else
     gl_deps = [gl, glew]
 endif
 
-chibi = dependency('chibi-scheme', required : false)
-readline = dependency('readline', required : false)
+chibi = dependency('chibi-scheme', required : false, static : static_libs)
+readline = dependency('readline', required : false, static : static_libs)
 
 flex = find_program('flex')
 bison = find_program('bison')

src/meson.build

@@ -140,8 +140,14 @@ if get_option('debugger').allowed()
     endif
 endif
 
+static_link_args = []
+if host_machine.system() == 'windows'
+    static_link_args = ['-static', '-lstdc++']
+endif
+
 executable('xsystem4', xsystem4,
            dependencies : xsystem4_deps,
            c_args : ['-Wno-unused-parameter'],
+           link_args : static_link_args,
            include_directories : incdir,
            install : true)