Build cleanup (#1)

* Move build script to build.rs
* Add homepage

.gitignore

@@ -1,3 +1,4 @@
 /target
 **/*.rs.bk
-Cargo.lock
+Cargo.lock
+MoltenVK

Cargo.toml

@@ -7,6 +7,7 @@ license = "MIT/Apache-2.0"
 readme = "README.md"
 keywords = ["vulkan", "metal"]
 repository = "https://github.com/EmbarkStudios/ash-molten"
+homepage = "https://github.com/EmbarkStudios/ash-molten"
 documentation = "https://docs.rs/ash-molten"
 
 [dependencies]

build.rs

@@ -1,58 +1,160 @@
-use std::path::PathBuf;
-// Iterator over target_os cfg flags
-fn target_os() -> impl Iterator<Item = String> {
-    std::env::vars().filter_map(|(flag, val)| {
-        const NAME: &'static str = "CARGO_CFG_TARGET_OS";
-        if flag.starts_with(NAME) {
-            Some(val)
-        } else {
-            None
-        }
-    })
-}
-// Features are not used inside build scripts, so we have to explicitly query them from the
-// enviroment
-fn is_external_enabled() -> bool {
-    std::env::vars()
-        .filter_map(|(flag, _)| {
-            const NAME: &'static str = "CARGO_FEATURE_";
-            if flag.starts_with(NAME) {
-                let feature = flag.split(NAME).nth(1).expect("").to_string();
-                println!("{:?}", feature);
-                return Some(feature);
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+mod mac {
+    use std::path::{Path, PathBuf};
+
+    // Features are not used inside build scripts, so we have to explicitly query them from the
+    // enviroment
+    pub(crate) fn is_external_enabled() -> bool {
+        std::env::vars()
+            .filter_map(|(flag, _)| {
+                const NAME: &'static str = "CARGO_FEATURE_";
+                if flag.starts_with(NAME) {
+                    let feature = flag.split(NAME).nth(1).expect("").to_string();
+                    println!("{:?}", feature);
+                    return Some(feature);
+                }
+                None
+            })
+            .find(|f| f == "EXTERNAL")
+            .is_some()
+    }
+
+    pub(crate) fn build_molten<P: AsRef<Path>>(target_dir: &P) -> &'static str {
+        use std::{
+            process::Command,
+            sync::{
+                atomic::{AtomicBool, Ordering},
+                Arc,
+            },
+        };
+
+        let exit = Arc::new(AtomicBool::new(false));
+        let wants_exit = exit.clone();
+
+        // Periodically emit log messages so that Travis doesn't make a sad
+        let handle = std::thread::spawn(move || {
+            let mut counter = 0;
+            while !wants_exit.load(Ordering::Acquire) {
+                std::thread::sleep(std::time::Duration::from_millis(100));
+                counter += 100;
+
+                if counter >= 30 * 1000 {
+                    counter = 0;
+                    println!("still building MoltenVK");
+                }
             }
-            None
-        })
-        .find(|f| f == "EXTERNAL")
-        .is_some()
-}
-fn main() {
-    let supported_platforms = ["macos", "ios"];
-    let is_mac_or_ios = target_os()
-        .find(|target| supported_platforms.contains(&target.as_str()))
-        .is_some();
-    if !is_mac_or_ios {
-        panic!("ash-molten can only be built on macOS or of iOS");
-    }
-    // The 'external' feature was not enabled. Molten will be built automaticaly.
-    if !is_external_enabled() {
-        let mut build = std::process::Command::new("bash")
-            .arg("build_molten.sh")
+        });
+
+        let git_status = if Path::new("MoltenVK").exists() {
+            Command::new("git")
+                .arg("pull")
+                .spawn()
+                .expect("failed to spawn git")
+                .wait()
+                .expect("failed to pull MoltenVK")
+        } else {
+            Command::new("git")
+                .arg("clone")
+                .arg("https://github.com/KhronosGroup/MoltenVK.git")
+                .spawn()
+                .expect("failed to spawn git")
+                .wait()
+                .expect("failed to clone MoltenVK")
+        };
+
+        assert!(git_status.success(), "failed to clone MoltenVK");
+
+        let status = Command::new("sh")
+            .current_dir("MoltenVK")
+            .arg("fetchDependencies")
             .spawn()
-            .expect("Unable to build molten");
-        while build.try_wait().unwrap().is_none() {
-            println!("Still building MoltenVK");
-            std::thread::sleep(std::time::Duration::from_secs(30));
+            .expect("failed to spawn fetchDependencies")
+            .wait()
+            .expect("failed to fetchDependencies");
+
+        assert!(status.success(), "failed to fetchDependencies");
+
+        // These (currently) match the identifiers used by moltenvk
+        let (target_name, dir) = match std::env::var("CARGO_CFG_TARGET_OS") {
+            Ok(target) => match target.as_ref() {
+                "macos" => ("macos", "macOS"),
+                "ios" => ("ios", "iOS"),
+                target => panic!("unknown target '{}'", target),
+            },
+            Err(e) => panic!("failed to determinte target os '{}'", e),
+        };
+
+        let status = Command::new("make")
+            .current_dir("MoltenVK")
+            .arg(target_name)
+            .spawn()
+            .expect("failed to spawn fetchDependencies")
+            .wait()
+            .expect("failed to fetchDependencies");
+
+        assert!(status.success(), "failed to fetchDependencies");
+
+        let src = {
+            let mut pb = PathBuf::new();
+            pb.push("MoltenVK");
+            pb.push("Package/Release/MoltenVK");
+            pb.push(dir);
+            pb.push("static/libMoltenVK.a");
+            pb
+        };
+
+        let target = {
+            let mut pb = PathBuf::new();
+            pb.push(target_dir);
+            pb.push(format!("lib{}MoltenVK.a", target_name));
+            pb
+        };
+
+        if let Err(e) = std::fs::copy(&src, &target) {
+            panic!("failed to copy {:?} to {:?}: {}", src, target, e);
         }
-        let project_dir =
-            PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap()).join("native");
-        println!("cargo:rustc-link-search=native={}", project_dir.display());
+
+        exit.store(true, Ordering::Release);
+        handle.join().unwrap();
+        target_name
     }
+}
+
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+fn main() {
+    use crate::mac::*;
+    use std::path::{Path, PathBuf};
+
+    // The 'external' feature was not enabled. Molten will be built automaticaly.
+    let target_name = if !is_external_enabled() {
+        let target_dir = Path::new("native");
+
+        let target_name = build_molten(&target_dir);
+        let project_dir = PathBuf::from(
+            std::env::var("CARGO_MANIFEST_DIR").expect("unable to find env:CARGO_MANIFEST_DIR"),
+        )
+        .join(target_dir);
+        println!("cargo:rustc-link-search=native={}", project_dir.display());
+
+        target_name
+    } else if cfg!(target_os = "macos") {
+        "macos"
+    } else if cfg!(target_os = "ios") {
+        "ios"
+    } else {
+        unreachable!();
+    };
+
     println!("cargo:rustc-link-lib=framework=Metal");
     println!("cargo:rustc-link-lib=framework=AppKit");
     println!("cargo:rustc-link-lib=framework=QuartzCore");
     println!("cargo:rustc-link-lib=framework=IOKit");
     println!("cargo:rustc-link-lib=framework=IOSurface");
     println!("cargo:rustc-link-lib=dylib=c++");
-    println!("cargo:rustc-link-lib=static=MoltenVK");
+    println!("cargo:rustc-link-lib=static={}MoltenVK", target_name);
+}
+
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+fn main() {
+    eprintln!("ash-molten requires either 'macos' or 'ios' target");
 }

build_molten.sh

@@ -1,5 +0,0 @@
-git clone https://github.com/KhronosGroup/MoltenVK.git
-cd MoltenVK
-sh fetchDependencies
-make macos
-cp Package/Release/MoltenVK/macOS/static/libMoltenVK.a ../native