Setup development environment with libbpf

external/libbpf-bootstrap/examples/rust/tracecon/build.rs

@@ -0,0 +1,23 @@
+use std::fs::create_dir_all;
+use std::path::Path;
+
+use libbpf_cargo::SkeletonBuilder;
+
+const SRC: &str = "./src/bpf/tracecon.bpf.c";
+
+fn main() {
+    // It's unfortunate we cannot use `OUT_DIR` to store the generated skeleton.
+    // Reasons are because the generated skeleton contains compiler attributes
+    // that cannot be `include!()`ed via macro. And we cannot use the `#[path = "..."]`
+    // trick either because you cannot yet `concat!(env!("OUT_DIR"), "/skel.rs")` inside
+    // the path attribute either (see https://github.com/rust-lang/rust/pull/83366).
+    //
+    // However, there is hope! When the above feature stabilizes we can clean this
+    // all up.
+    create_dir_all("./src/bpf/.output").unwrap();
+    let skel = Path::new("./src/bpf/.output/tracecon.skel.rs");
+    SkeletonBuilder::new(SRC)
+        .generate(&skel)
+        .expect("bpf compilation failed");
+    println!("cargo:rerun-if-changed={}", SRC);
+}