Remove build-helper dependency (#18)

The build-helper crate and repo has not been updated in 2 years and looks abandoned, and we have a long running PR for it (DanielKeep/rust-build-helper#2) with some dependency updates that haven't been merged in nor any communication about.

So let's just remove the dependency and use explicit Cargo env vars and prinln instructions instead, easy enough.

physx-sys/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "physx-sys"
 description = "Unsafe bindings for NVIDIA PhysX C++ SDK"
-version = "0.1.0+4.1"
+version = "0.1.1+4.1"
 authors = ["Embark <opensource@embark-studios.com>", "Tomasz Stachowiak <h3@h3.gd>"]
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/EmbarkStudios/physx-rs"
@@ -37,4 +37,3 @@ doctest = false
 [build-dependencies]
 cc = "1.0"
 cmake = "0.1.35"
-build-helper = "0.1.1"

physx-sys/build.rs

@@ -1,23 +1,24 @@
 use cmake::Config;
 use std::env;
 use std::ffi::OsString;
+use std::path::PathBuf;
 
 #[cfg(debug_assertions)]
 fn get_bin_dir() -> (&'static str, &'static str) {
-    match build_helper::target::triple().os() {
+    match env::var("CARGO_CFG_TARGET_OS").unwrap().as_str() {
         "linux" => ("linux", "bin/linux.clang/debug"),
         "windows" => ("windows", "bin/win.x86_64.vc141.md/debug"),
-        "darwin" => ("mac", "bin/mac.x86_64/debug"),
+        "macos" => ("mac", "bin/mac.x86_64/debug"),
         p @ _ => panic!("Unsupported platform: {}", p),
     }
 }
 
 #[cfg(not(debug_assertions))]
 fn get_bin_dir() -> (&'static str, &'static str) {
-    match build_helper::target::triple().os() {
+    match env::var("CARGO_CFG_TARGET_OS").unwrap().as_str() {
         "linux" => ("linux", "bin/linux.clang/profile"),
         "windows" => ("windows", "bin/win.x86_64.vc141.md/profile"),
-        "darwin" => ("mac", "bin/mac.x86_64/profile"),
+        "macos" => ("mac", "bin/mac.x86_64/profile"),
         p @ _ => panic!("Unsupported platform: {}", p),
     }
 }
@@ -54,8 +55,8 @@ fn main() {
     );
     env::set_var("PM_PATHS", env::var("PM_opengllinux_PATH").unwrap());
 
-    let output_dir_path = build_helper::out_dir();
-    let output_dir = output_dir_path.to_string_lossy().into_owned();
+    let output_dir = env::var("OUT_DIR").unwrap();
+    let output_dir_path: PathBuf = output_dir.clone().into();
 
     let build_mode = if cfg!(debug_assertions) {
         "debug"
@@ -172,13 +173,13 @@ fn main() {
         .file("src/physx.cpp")
         .compile("physx_api");
 
-    build_helper::rerun_if_changed("src/structgen/structgen.cpp");
-    build_helper::rerun_if_changed("src/structgen/structgen.hpp");
-    build_helper::rerun_if_changed("src/lib.rs");
-    build_helper::rerun_if_changed("src/physx_generated.hpp");
-    build_helper::rerun_if_changed("src/physx_generated.rs");
-    build_helper::rerun_if_changed("src/physx.cpp");
+    println!("cargo:rerun-if-changed=src/structgen/structgen.cpp");
+    println!("cargo:rerun-if-changed=src/structgen/structgen.hpp");
+    println!("cargo:rerun-if-changed=src/lib.rs");
+    println!("cargo:rerun-if-changed=src/physx_generated.hpp");
+    println!("cargo:rerun-if-changed=src/physx_generated.rs");
+    println!("cargo:rerun-if-changed=src/physx.cpp");
 
     // TODO: use the cloned git revision number instead
-    build_helper::rerun_if_changed("PhysX/physx/include/PxPhysicsVersion.h");
+    println!("cargo:rerun-if-changed=PhysX/physx/include/PxPhysicsVersion.h");
 }