1 use pathdiff::diff_paths;
2 use rustc_data_structures::fx::FxHashSet;
5 use std::path::{Path, PathBuf};
7 use rustc_hir::def_id::CrateNum;
8 use rustc_middle::middle::cstore::LibSource;
10 pub struct RPathConfig<'a> {
11 pub used_crates: &'a [(CrateNum, LibSource)],
12 pub out_filename: PathBuf,
13 pub is_like_osx: bool,
15 pub linker_is_gnu: bool,
16 pub get_install_prefix_lib_path: &'a mut dyn FnMut() -> PathBuf,
19 pub fn get_rpath_flags(config: &mut RPathConfig<'_>) -> Vec<String> {
20 // No rpath on windows
21 if !config.has_rpath {
25 debug!("preparing the RPATH!");
27 let libs = config.used_crates;
28 let libs = libs.iter().filter_map(|&(_, ref l)| l.option()).collect::<Vec<_>>();
29 let rpaths = get_rpaths(config, &libs);
30 let mut flags = rpaths_to_flags(&rpaths);
32 // Use DT_RUNPATH instead of DT_RPATH if available
33 if config.linker_is_gnu {
34 flags.push("-Wl,--enable-new-dtags".to_owned());
40 fn rpaths_to_flags(rpaths: &[String]) -> Vec<String> {
41 let mut ret = Vec::with_capacity(rpaths.len()); // the minimum needed capacity
44 if rpath.contains(',') {
45 ret.push("-Wl,-rpath".into());
46 ret.push("-Xlinker".into());
47 ret.push(rpath.clone());
49 ret.push(format!("-Wl,-rpath,{}", &(*rpath)));
56 fn get_rpaths(config: &mut RPathConfig<'_>, libs: &[PathBuf]) -> Vec<String> {
57 debug!("output: {:?}", config.out_filename.display());
60 debug!(" {:?}", libpath.display());
63 // Use relative paths to the libraries. Binaries can be moved
64 // as long as they maintain the relative relationship to the
65 // crates they depend on.
66 let rel_rpaths = get_rpaths_relative_to_output(config, libs);
68 // And a final backup rpath to the global library location.
69 let fallback_rpaths = vec![get_install_prefix_rpath(config)];
71 fn log_rpaths(desc: &str, rpaths: &[String]) {
72 debug!("{} rpaths:", desc);
74 debug!(" {}", *rpath);
78 log_rpaths("relative", &rel_rpaths);
79 log_rpaths("fallback", &fallback_rpaths);
81 let mut rpaths = rel_rpaths;
82 rpaths.extend_from_slice(&fallback_rpaths);
85 minimize_rpaths(&rpaths)
88 fn get_rpaths_relative_to_output(config: &mut RPathConfig<'_>, libs: &[PathBuf]) -> Vec<String> {
89 libs.iter().map(|a| get_rpath_relative_to_output(config, a)).collect()
92 fn get_rpath_relative_to_output(config: &mut RPathConfig<'_>, lib: &Path) -> String {
93 // Mac doesn't appear to support $ORIGIN
94 let prefix = if config.is_like_osx { "@loader_path" } else { "$ORIGIN" };
96 let cwd = env::current_dir().unwrap();
97 let mut lib = fs::canonicalize(&cwd.join(lib)).unwrap_or_else(|_| cwd.join(lib));
98 lib.pop(); // strip filename
99 let mut output = cwd.join(&config.out_filename);
100 output.pop(); // strip filename
101 let output = fs::canonicalize(&output).unwrap_or(output);
102 let relative = path_relative_from(&lib, &output)
103 .unwrap_or_else(|| panic!("couldn't create relative path from {:?} to {:?}", output, lib));
104 // FIXME (#9639): This needs to handle non-utf8 paths
105 format!("{}/{}", prefix, relative.to_str().expect("non-utf8 component in path"))
108 // This routine is adapted from the *old* Path's `path_relative_from`
109 // function, which works differently from the new `relative_from` function.
110 // In particular, this handles the case on unix where both paths are
111 // absolute but with only the root as the common directory.
112 fn path_relative_from(path: &Path, base: &Path) -> Option<PathBuf> {
113 diff_paths(path, base)
116 fn get_install_prefix_rpath(config: &mut RPathConfig<'_>) -> String {
117 let path = (config.get_install_prefix_lib_path)();
118 let path = env::current_dir().unwrap().join(&path);
119 // FIXME (#9639): This needs to handle non-utf8 paths
120 path.to_str().expect("non-utf8 component in rpath").to_owned()
123 fn minimize_rpaths(rpaths: &[String]) -> Vec<String> {
124 let mut set = FxHashSet::default();
125 let mut minimized = Vec::new();
126 for rpath in rpaths {
127 if set.insert(rpath) {
128 minimized.push(rpath.clone());
134 #[cfg(all(unix, test))]