Re-implement the build of libbpf

Author: editso

build.rs

@@ -2,7 +2,6 @@
 
 use std::env;
 use std::ffi;
-use std::fs;
 use std::fs::read_dir;
 use std::path;
 use std::path::Path;
@@ -376,46 +375,52 @@ fn make_elfutils(compiler: &cc::Tool, src_dir: &path::Path, _: &path::Path) {
     emit_rerun_directives_for_contents(&src_dir.join("elfutils").join("src"));
 }
 
-fn make_libbpf(
-    compiler: &cc::Tool,
-    cflags: &ffi::OsStr,
-    src_dir: &path::Path,
-    out_dir: &path::Path,
-) {
-    let src_dir = src_dir.join("libbpf/src");
-    // create obj_dir if it doesn't exist
-    let obj_dir = path::PathBuf::from(&out_dir.join("obj").into_os_string());
-    let _ = fs::create_dir(&obj_dir);
-
-    let status = process::Command::new("make")
-        .arg("install")
-        .arg("-j")
-        .arg(&format!("{}", num_cpus()))
-        .env("BUILD_STATIC_ONLY", "y")
-        .env("PREFIX", "/")
-        .env("LIBDIR", "")
-        .env("OBJDIR", &obj_dir)
-        .env("DESTDIR", out_dir)
-        .env("CC", compiler.path())
-        .env("CFLAGS", cflags)
-        .current_dir(&src_dir)
-        .status()
-        .expect("could not execute make");
+fn make_libbpf(compiler: &cc::Tool, _: &ffi::OsStr, src_dir: &path::Path, _: &path::Path) {
+    let project_dir = src_dir.join("libbpf");
 
-    assert!(status.success(), "make failed");
+    let project = project_dir.to_str().unwrap();
 
-    let status = process::Command::new("make")
-        .arg("clean")
-        .current_dir(&src_dir)
-        .status()
-        .expect("could not execute make");
+    let mut builder = cc::Build::new();
 
-    assert!(status.success(), "make failed");
-    emit_rerun_directives_for_contents(&src_dir);
-}
+    builder
+        .include(src_dir)
+        .include(src_dir.join("zlib"))
+        .include(src_dir.join("elfutils").join("libelf"))
+        .include(format!("{project}/src"))
+        .include(format!("{project}/include"))
+        .include(format!("{project}/include/uapi"));
+
+    if build_android() {
+        let cflags = ["-DCOMPAT_NEED_REALLOCARRAY"];
+
+        builder.flag("-includeandroid/android.h");
+
+        for flag in cflags {
+            builder.flag(flag);
+        }
+    } else {
+        builder.compiler(compiler.path());
+
+        for flag in compiler.args() {
+            builder.flag(flag);
+        }
+    }
+
+    for entry in std::fs::read_dir(project_dir.join("src")).expect("Failed to `read_dir`") {
+        let entry = entry.unwrap();
+        if entry.file_type().unwrap().is_file()
+            && entry.file_name().to_str().unwrap().ends_with(".c")
+        {
+            builder.file(entry.path());
+        }
+    }
+
+    builder
+        .flag_if_supported("-w")
+        .warnings(false)
+        .compile("bpf");
 
-fn num_cpus() -> usize {
-    std::thread::available_parallelism().map_or(1, |count| count.get())
+    emit_rerun_directives_for_contents(&src_dir);
 }
 
 fn build_android() -> bool {