Introduce libbpf-rs-dev crate

Our test file generation logic has grown and gotten more complex. To
mitigate the situation somewhat, move all this stuff into a separate
workspace member: libbpf-rs-dev.

Signed-off-by: Daniel Müller <[email protected]>

Author: d-e-s-o

Cargo.lock

@@ -10,6 +10,7 @@ homepage = "https://github.com/libbpf/libbpf-rs"
 members = [
   "libbpf-cargo",
   "libbpf-rs",
+  "libbpf-rs/dev",
   "examples/bpf_query",
   "examples/capable",
   "examples/runqslower",

Cargo.toml

@@ -45,6 +45,7 @@ tempfile = { version = "3.3", optional = true }
 
 [dev-dependencies]
 libbpf-rs = {path = ".", features = ["generate-test-files"]}
+libbpf-rs-dev = {path = "dev", features = ["generate-test-files"]}
 log = "0.4.4"
 memmem = "0.1.1"
 plain = "0.2.3"

libbpf-rs/Cargo.toml

@@ -0,0 +1,23 @@
+# A development-only package for generating libbpf-rs test artifacts.
+
+[package]
+name = "libbpf-rs-dev"
+version = "0.0.0"
+edition.workspace = true
+authors = ["Daniel Müller <[email protected]>"]
+publish = false
+
+[lib]
+path = "lib.rs"
+
+[features]
+# Enable this feature to opt in to the generation of unit test files.
+# Having these test files created is necessary for running tests.
+generate-test-files = ["libbpf-sys/vendored-libbpf", "dep:tempfile"]
+# Disable generation of test files. This feature takes preference over
+# `generate-test-files`.
+dont-generate-test-files = []
+
+[build-dependencies]
+libbpf-sys = { version = "1.4.1", default-features = false, optional = true }
+tempfile = { version = "3.3", optional = true }

libbpf-rs/dev/Cargo.toml

@@ -271,9 +271,12 @@ fn prepare_test_files(crate_root: &Path) {
 }
 
 fn main() {
-    let crate_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
+    let crate_dir = Path::new(&env::var("CARGO_MANIFEST_DIR").unwrap())
+        .parent()
+        .unwrap()
+        .to_path_buf();
 
     if cfg!(feature = "generate-test-files") && !cfg!(feature = "dont-generate-test-files") {
-        prepare_test_files(crate_dir.as_ref());
+        prepare_test_files(&crate_dir);
     }
 }

libbpf-rs/build.rs libbpf-rs/dev/build.rslibbpf-rs/build.rs renamed to libbpf-rs/dev/build.rs

@@ -0,0 +1 @@
+