call bindgen on build in rustables

1 files changed, 122 insertions, 10 deletions

diff --git a/rustables/build.rs b/rustables/build.rs
index fee34ff..180e06b 100644
--- a/rustables/build.rs
+++ b/rustables/build.rs
@@ -1,13 +1,64 @@
 use bindgen;
-
+use lazy_static::lazy_static;
+use regex::{Captures, Regex};
+use pkg_config;
+use std::env;
 use std::fs::File;
 use std::io::Write;
 use std::path::PathBuf;
 use std::borrow::Cow;
-use lazy_static::lazy_static;
-use regex::{Captures, Regex};
 
 
+const SYS_HEADER_FILE: &str = "wrapper.h";
+const SYS_BINDINGS_FILE: &str = "src/sys.rs";
+const TESTS_HEADER_FILE: &str = "tests_wrapper.h";
+const TESTS_BINDINGS_FILE: &str = "tests/sys.rs";
+const MIN_LIBNFTNL_VERSION: &str = "1.0.6";
+
+
+fn get_env(var: &'static str) -> Option<PathBuf> {
+    println!("cargo:rerun-if-env-changed={}", var);
+    env::var_os(var).map(PathBuf::from)
+}
+
+/// Set env vars to help rustc find linked libraries.
+fn setup_libs() {
+    if let Some(lib_dir) = get_env("LIBNFTNL_LIB_DIR") {
+        if !lib_dir.is_dir() {
+            panic!(
+                "libnftnl library directory does not exist: {}",
+                lib_dir.display()
+            );
+        }
+        println!("cargo:rustc-link-search=native={}", lib_dir.display());
+        println!("cargo:rustc-link-lib=nftnl");
+    } else {
+        // Trying with pkg-config instead
+        println!("Minimum libnftnl version: {}", MIN_LIBNFTNL_VERSION);
+        pkg_config::Config::new()
+            .atleast_version(MIN_LIBNFTNL_VERSION)
+            .probe("libnftnl")
+            .unwrap();
+    }
+
+    if let Some(lib_dir) = get_env("LIBMNL_LIB_DIR") {
+        if !lib_dir.is_dir() {
+            panic!(
+                "libmnl library directory does not exist: {}",
+                lib_dir.display()
+            );
+        }
+        println!("cargo:rustc-link-search=native={}", lib_dir.display());
+        println!("cargo:rustc-link-lib=mnl");
+    } else {
+        // Trying with pkg-config instead
+        pkg_config::Config::new()
+            .atleast_version("1.0.0")
+            .probe("libmnl")
+            .unwrap();
+    }
+}
+
 /// Recast nft_*_attributes from u32 to u16 in header file `before`.
 fn reformat_units(before: &str) -> Cow<str> {
     lazy_static! {
@@ -18,31 +69,92 @@ fn reformat_units(before: &str) -> Cow<str> {
     })
 }
 
-fn main() {
+fn generate_consts() {
     // Tell cargo to invalidate the built crate whenever the headers change.
-    println!("cargo:rerun-if-changed=wrapper.h");
+    println!("cargo:rerun-if-changed={}", SYS_HEADER_FILE);
 
     let bindings = bindgen::Builder::default()
-        .header("wrapper.h")
+        .header(SYS_HEADER_FILE)
         .generate_comments(false)
         .prepend_enum_name(false)
+        .use_core()
+        .whitelist_function("^nftnl_.+$")
+        .whitelist_type("^nftnl_.+$")
+        .whitelist_var("^nftnl_.+$")
+        .whitelist_var("^NFTNL_.+$")
+        .blacklist_type("(FILE|iovec)")
+        .blacklist_type("^_IO_.+$")
+        .blacklist_type("^__.+$")
+        .blacklist_type("nlmsghdr")
+        .raw_line("#![allow(non_camel_case_types)]\n\n")
+        .raw_line("pub use libc;")
+        .raw_line("use libc::{c_char, c_int, c_ulong, c_void, iovec, nlmsghdr, FILE};")
+        .raw_line("use core::option::Option;")
+        .ctypes_prefix("libc")
         // Tell cargo to invalidate the built crate whenever any of the
         // included header files changed.
         .parse_callbacks(Box::new(bindgen::CargoCallbacks))
         // Finish the builder and generate the bindings.
         .generate()
         // Unwrap the Result and panic on failure.
-        .expect("Unable to generate bindings");
+        .expect("Error: unable to generate bindings");
+
+    let mut s = bindings.to_string()
+                    // Add newlines because in alpine bindgen doesn't add them after
+                    // statements.
+                    .replace(" ; ", ";\n")
+                    .replace("#[derive(Debug, Copy, Clone)]", "");
+    let re = Regex::new(r"libc::(c_[a-z]*)").unwrap();
+    s = re.replace_all(&s, "$1").into();
+    let re = Regex::new(r"::core::option::(Option)").unwrap();
+    s = re.replace_all(&s, "$1").into();
+    let re = Regex::new(r"_bindgen_ty_[0-9]+").unwrap();
+    s = re.replace_all(&s, "u32").into();
+    // Change struct bodies to c_void.
+    let re = Regex::new(r"(pub struct .*) \{\n    *_unused: \[u8; 0\],\n\}\n").unwrap();
+    s = re.replace_all(&s, "$1(c_void);\n").into();
+    let re = Regex::new(r"pub type u32 = u32;\n").unwrap();
+    s = re.replace_all(&s, "").into();
+
+    // Write the bindings to the rust header file.
+    let out_path = PathBuf::from(SYS_BINDINGS_FILE);
+    File::create(out_path)
+         .expect("Error: could not create rust header file.")
+         .write_all(&s.as_bytes())
+         .expect("Error: could not write to the rust header file.");
+}
+
+fn generate_test_consts() {
+    // Tell cargo to invalidate the built crate whenever the headers change.
+    println!("cargo:rerun-if-changed={}", TESTS_HEADER_FILE);
+
+    let bindings = bindgen::Builder::default()
+        .header(TESTS_HEADER_FILE)
+        .generate_comments(false)
+        .prepend_enum_name(false)
+        .raw_line("#![allow(non_camel_case_types, dead_code)]\n\n")
+        // Tell cargo to invalidate the built crate whenever any of the
+        // included header files changed.
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks))
+        // Finish the builder and generate the bindings.
+        .generate()
+        // Unwrap the Result and panic on failure.
+        .expect("Error: unable to generate bindings needed for tests.");
 
     // Add newlines because in alpine bindgen doesn't add them after statements.
     let s = bindings.to_string().replace(" ; ", ";\n");
     let s = reformat_units(&s);
-    let h = String::from("#![allow(non_camel_case_types, dead_code)]\n\n") + &s;
 
     // Write the bindings to the rust header file.
-    let out_path = PathBuf::from("src/tests/bindings.rs");
+    let out_path = PathBuf::from(TESTS_BINDINGS_FILE);
     File::create(out_path)
          .expect("Error: could not create rust header file.")
-         .write_all(&h.as_bytes())
+         .write_all(&s.as_bytes())
          .expect("Error: could not write to the rust header file.");
 }
+
+fn main() {
+    setup_libs();
+    generate_consts();
+    generate_test_consts();
+}