Update build script

Former-commit-id: fd39635fc5

addons/godot_xterm/native/bin/x11/libgodotxtermnative.so.REMOVED.git-id

@@ -1 +1 @@
-1dcc20e0ef6e62c4371e3345e33bef19229c471a
+a17dbf3cdfca56910de1517e42a39770c19aef81

addons/godot_xterm/native/build.sh

@@ -1,28 +1,37 @@
-#! /usr/bin/env nix-shell
-#! nix-shell -i bash --pure -p binutils.bintools cmake scons
+#!/bin/sh
 set -e
 
-# Make sure we are in the addons/godot_xterm directory
-cd ${BASH_SOURCE%/*}
+# Get the absolute path to the directory this script is in.
+NATIVE_DIR="$( cd "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"
 
-# Initialize godot-cpp
-if [ ! -d "external/godot-cpp/bin" ]
-then
-	cd external/godot-cpp
-	scons platform=linux generate_bindings=yes -j12
-	cd ../..
+# Run script inside a nix shell if it is available.
+if command -v nix-shell && [ $NIX_PATH ] && [ -z $IN_NIX_SHELL ]; then
+	cd ${NATIVE_DIR}
+	nix-shell shell.nix --pure --run "./build.sh"
+	exit
 fi
 
-# Build libtsm
-if [ ! -f "external/libtsm/build/src/tsm/libtsm.a" ]
-then
-	cd external/libtsm
-	mkdir -p build
-	cd build
-	cmake -DBUILD_SHARED_LIBS=n ..
-	make
-	cd ../../..
+# Build libtsm.
+LIBTSM_DIR=${NATIVE_DIR}/external/libtsm
+if [ ! -d "$LIBTSM_DIR" ]; then
+	cd ${NATIVE_DIR}
+	git submodule update --init --recursive -- $LIBTSM_DIR
 fi
+cd $LIBTSM_DIR
+mkdir -p build
+cd build
+cmake -DBUILD_SHARED_LIBS=n ..
+make
 
-# Build godotxtermnative
+# Build godot-cpp.
+GODOT_CPP_DIR=${NATIVE_DIR}/external/godot-cpp
+if [ ! -d "${GODOT_CPP_DIR}" ]; then
+	cd ${NATIVE_DIR}
+	git submodule update --init --recursive -- $GODOT_CPP_DIR
+fi
+cd $GODOT_CPP_DIR
+scons platform=linux generate_bindings=yes -j12
+
+# Build godotxtermnative.
+cd ${NATIVE_DIR}
 scons platform=linux

addons/godot_xterm/native/shell.nix

@@ -0,0 +1,11 @@
+with (import <nixpkgs> {});
+mkShell {
+  buildInputs = with pkgs; [
+    binutils.bintools
+    cmake
+    git
+    libxkbcommon
+    pkg-config
+    scons
+  ];
+}