1// SPDX-License-Identifier: Apache-2.0 2 3//! Finds `libclang` static or shared libraries and links to them. 4//! 5//! # Environment Variables 6//! 7//! This build script can make use of several environment variables to help it 8//! find the required static or shared libraries. 9//! 10//! * `LLVM_CONFIG_PATH` - provides a path to an `llvm-config` executable 11//! * `LIBCLANG_PATH` - provides a path to a directory containing a `libclang` 12//! shared library or a path to a specific `libclang` shared library 13//! * `LIBCLANG_STATIC_PATH` - provides a path to a directory containing LLVM 14//! and Clang static libraries 15 16#![allow(unused_attributes)] 17 18extern crate glob; 19 20use std::path::Path; 21 22#[path = "build/common.rs"] 23pub mod common; 24#[path = "build/dynamic.rs"] 25pub mod dynamic; 26#[path = "build/static.rs"] 27pub mod r#static; 28 29/// Copies a file. 30#[cfg(feature = "runtime")] 31fn copy(source: &str, destination: &Path) { 32 use std::fs::File; 33 use std::io::{Read, Write}; 34 35 let mut string = String::new(); 36 File::open(source) 37 .unwrap() 38 .read_to_string(&mut string) 39 .unwrap(); 40 File::create(destination) 41 .unwrap() 42 .write_all(string.as_bytes()) 43 .unwrap(); 44} 45 46/// Copies the code used to find and link to `libclang` shared libraries into 47/// the build output directory so that it may be used when linking at runtime. 48#[cfg(feature = "runtime")] 49fn main() { 50 use std::env; 51 52 if cfg!(feature = "static") { 53 panic!("`runtime` and `static` features can't be combined"); 54 } 55 56 let out = env::var("OUT_DIR").unwrap(); 57 copy("build/common.rs", &Path::new(&out).join("common.rs")); 58 copy("build/dynamic.rs", &Path::new(&out).join("dynamic.rs")); 59} 60 61/// Finds and links to the required libraries dynamically or statically. 62#[cfg(not(feature = "runtime"))] 63fn main() { 64 if cfg!(feature = "static") { 65 // r#static::link(); 66 } else { 67 dynamic::link(); 68 } 69 70 if let Some(output) = common::run_llvm_config(&["--includedir"]) { 71 let directory = Path::new(output.trim_end()); 72 println!("cargo:include={}", directory.display()); 73 } 74} 75