Add the CMake build system generator option back for Windows.

This option was in the autogen.sh (based on uname instead of proper
detection by configure script, which is now also changed). Add it back
properly in the Makefile rule. Of course it will be used only for
**native** builds on Windows for Windows. Cross-builds for the
librtprocess dependency are still to be done separately.

Also move the rules inside deps/Makefile as it should be, now that we
have a Makefile.am there.

Makefile.am

@@ -8,17 +8,6 @@ SUBDIRS = deps \
 	pixmaps \
 	platform-specific
 
-if !HAVE_LIBRTPROCESS
-# not adding it in subdirs because we don't want to run most targets in it, and specifying
-# the rtprocess_static target allows us to build only the static lib we link against
-build-librtprocess:
-	mkdir -p $(top_builddir)/deps/librtprocess/build
-	$(CMAKE) -DCMAKE_BUILD_TYPE="Release" -DWITH_STATIC_LIB=ON -DOPTION_OMP=OFF -S $(top_srcdir)/deps/librtprocess/ -B $(top_builddir)/deps/librtprocess/build
-	$(MAKE) -C $(top_builddir)/deps/librtprocess/build rtprocess_static
-
-all: build-librtprocess
-endif
-
 # TODO add a conditionnal and a configure switch
 # to be able to choose the language. Also, this should
 # be a recussive make with a separate file list.

configure.ac

@@ -96,6 +96,20 @@ if test "x$STD_ATOMIC_NEED_LIBATOMIC" = xyes; then
 fi
 AC_SUBST([LIBATOMIC_LIBS])
 
+dnl ================ PLATFORM CHECKS ================
+
+AC_MSG_CHECKING([if compiling for Win32])
+case "$host_os" in
+  mingw* | cygwin*)
+    platform_win32=yes
+    ;;
+  *)
+    platform_win32=no
+    ;;
+esac
+AC_MSG_RESULT([$platform_win32])
+AM_CONDITIONAL(PLATFORM_WIN32, test "$platform_win32" = "yes")
+
 dnl ================ MANDATORY DEPENDECIES ================
 dnl check math lib
 AC_CHECK_LIB(m, log, LIBS="$LIBS -lm")
@@ -162,6 +176,13 @@ if test "x$have_rtprocess" = "xno"; then
     if test "x$CMAKE" = xno; then
       AC_MSG_ERROR([CMAKE not found (needed to built internal librtprocess)])
     fi
+
+    CMAKE_GENERATOR=
+    if test "$platform_win32" = "yes"; then
+      CMAKE_GENERATOR="-G \"MSYS Makefiles\""
+    fi
+    AC_SUBST([CMAKE_GENERATOR])
+
     AC_MSG_NOTICE([librtprocess will be built statically])
   else
     # When cross-compiling, you should build rtprocess yourself and

deps/Makefile.am

@@ -10,3 +10,14 @@ all-local:
 	if [ ! -f "$(top_builddir)/deps/kplot/Makefile" ]; then \
 		cp -fr "$(top_srcdir)/deps/kplot" "$(top_builddir)/deps/kplot"; \
 	fi
+
+if !HAVE_LIBRTPROCESS
+# not adding it in subdirs because we don't want to run most targets in it, and specifying
+# the rtprocess_static target allows us to build only the static lib we link against
+build-librtprocess:
+	mkdir -p $(top_builddir)/deps/librtprocess/build
+	$(CMAKE) $(CMAKE_GENERATOR) -DCMAKE_BUILD_TYPE="Release" -DWITH_STATIC_LIB=ON -DOPTION_OMP=OFF -S $(top_srcdir)/deps/librtprocess/ -B $(top_builddir)/deps/librtprocess/build
+	$(MAKE) -C $(top_builddir)/deps/librtprocess/build rtprocess_static
+
+all: build-librtprocess
+endif