Try to autodetect OS and CPU instead of requiring user input

configure

@@ -16,6 +16,25 @@ echo
 
 echo 'Welcome to the corner-cutting configure script !'
 echo
+
+OS=""
+case "`uname -s`" in
+Linux)
+	OS="linux"
+	;;
+FreeBSD)
+	OS="freebsd"
+	;;
+SunOS)
+	OS="solaris"
+	;;
+Darwin)
+	OS="macos"
+	;;
+OpenBSD)
+	OS="openbsd"
+	;;
+*)
 	echo 'Select your operating system below:'
 	echo ' 1: Linux'
 	echo ' 2: FreeBSD'
@@ -26,7 +45,6 @@ echo
 	echo -n 'Which is your operating system (1 - 5) ? : '
 	read TMP
 	echo
-OS=""
 	if test "$TMP" = "1"
 	then
 		OS="linux"
@@ -53,7 +71,18 @@ then
 		echo "Wrong number."
 		exit 1
 	fi
+	;;
+esac
 
+CPU=""
+case "`uname -m`" in
+x86_64|amd64|aarch64|arm64|armv8*|mips64|ppc64|sparc64|alpha|ia64)
+	CPU=64bit
+	;;
+i?86|x86pc|i86pc|armv4*|armv5*|armv6*|armv7*)
+	CPU=32bit
+	;;
+*)
 	echo 'Select your CPU bits below:'
 	echo ' 1: 32-bit'
 	echo ' 2: 64-bit'
@@ -61,7 +90,6 @@ echo
 	echo -n 'Which is the type of your CPU (1 - 2) ? : '
 	read TMP
 	echo
-CPU=""
 	if test "$TMP" = "1"
 	then
 		CPU="32bit"
@@ -76,6 +104,8 @@ then
 		echo "Wrong number."
 		exit 1
 	fi
+	;;
+esac
 
 cp src/makefiles/${OS}_${CPU}.mak Makefile