1 files changed, 74 insertions, 0 deletions
diff --git a/third_party/rust/clang-sys/build.rs b/third_party/rust/clang-sys/build.rs
new file mode 100644
index 0000000000..2826f97db7
--- /dev/null
+++ b/third_party/rust/clang-sys/build.rs
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: Apache-2.0
+
+//! Finds `libclang` static or shared libraries and links to them.
+//!
+//! # Environment Variables
+//!
+//! This build script can make use of several environment variables to help it
+//! find the required static or shared libraries.
+//!
+//! * `LLVM_CONFIG_PATH` - provides a path to an `llvm-config` executable
+//! * `LIBCLANG_PATH` - provides a path to a directory containing a `libclang`
+//!    shared library or a path to a specific `libclang` shared library
+//! * `LIBCLANG_STATIC_PATH` - provides a path to a directory containing LLVM
+//!    and Clang static libraries
+
+#![allow(unused_attributes)]
+
+extern crate glob;
+
+use std::path::Path;
+
+#[path = "build/common.rs"]
+pub mod common;
+#[path = "build/dynamic.rs"]
+pub mod dynamic;
+#[path = "build/static.rs"]
+pub mod r#static;
+
+/// Copies a file.
+#[cfg(feature = "runtime")]
+fn copy(source: &str, destination: &Path) {
+    use std::fs::File;
+    use std::io::{Read, Write};
+
+    let mut string = String::new();
+    File::open(source)
+        .unwrap()
+        .read_to_string(&mut string)
+        .unwrap();
+    File::create(destination)
+        .unwrap()
+        .write_all(string.as_bytes())
+        .unwrap();
+}
+
+/// Copies the code used to find and link to `libclang` shared libraries into
+/// the build output directory so that it may be used when linking at runtime.
+#[cfg(feature = "runtime")]
+fn main() {
+    use std::env;
+
+    if cfg!(feature = "static") {
+        panic!("`runtime` and `static` features can't be combined");
+    }
+
+    let out = env::var("OUT_DIR").unwrap();
+    copy("build/common.rs", &Path::new(&out).join("common.rs"));
+    copy("build/dynamic.rs", &Path::new(&out).join("dynamic.rs"));
+}
+
+/// Finds and links to the required libraries dynamically or statically.
+#[cfg(not(feature = "runtime"))]
+fn main() {
+    if cfg!(feature = "static") {
+        r#static::link();
+    } else {
+        dynamic::link();
+    }
+
+    if let Some(output) = common::run_llvm_config(&["--includedir"]) {
+        let directory = Path::new(output.trim_end());
+        println!("cargo:include={}", directory.display());
+    }
+}