stdbuf: updated 'build.rs' fixed issue #6981

Author: zcg00

src/uu/stdbuf/build.rs

@@ -24,53 +24,22 @@ mod platform {
 }
 
 fn main() {
-    let out_dir = env::var("OUT_DIR").unwrap();
-    let mut target_dir = Path::new(&out_dir);
+    let out_dir_string = env::var("OUT_DIR").unwrap();
+    let out_dir = Path::new(&out_dir_string);
 
-    // Depending on how this is util is built, the directory structure changes.
-    // This seems to work for now. Here are three cases to test when changing
-    // this:
-    //
-    // - cargo run
-    // - cross run
-    // - cargo install --git
-    // - cargo publish --dry-run
-    //
-    // The goal is to find the directory in which we are installing, but that
-    // depends on the build method, which is annoying. Additionally the env
-    // var for the profile can only be "debug" or "release", not a custom
-    // profile name, so we have to use the name of the directory within target
-    // as the profile name.
-    //
-    // Adapted from https://stackoverflow.com/questions/73595435/how-to-get-profile-from-cargo-toml-in-build-rs-or-at-runtime
-    let profile_name = out_dir
-        .split(std::path::MAIN_SEPARATOR)
-        .nth_back(3)
-        .unwrap();
+    let deps_dir = out_dir.ancestors().nth(3).unwrap().join("deps");
 
-    let mut name = target_dir.file_name().unwrap().to_string_lossy();
-    while name != "target" && !name.starts_with("cargo-install") {
-        target_dir = target_dir.parent().unwrap();
-        name = target_dir.file_name().unwrap().to_string_lossy();
-    }
-    let mut dir = target_dir.to_path_buf();
-    dir.push(profile_name);
-    dir.push("deps");
-    let mut path = None;
+    let libstdbuf = deps_dir
+        .read_dir()
+        .unwrap()
+        .flatten()
+        .find(|entry| {
+            let n = entry.file_name();
+            let name = n.to_string_lossy();
 
-    // When running cargo publish, cargo appends hashes to the filenames of the compiled artifacts.
-    // Therefore, it won't work to just get liblibstdbuf.so. Instead, we look for files with the
-    // glob pattern "liblibstdbuf*.so" (i.e. starts with liblibstdbuf and ends with the extension).
-    for entry in fs::read_dir(dir).unwrap().flatten() {
-        let name = entry.file_name();
-        let name = name.to_string_lossy();
-        if name.starts_with("liblibstdbuf") && name.ends_with(platform::DYLIB_EXT) {
-            path = Some(entry.path());
-        }
-    }
-    fs::copy(
-        path.expect("liblibstdbuf was not found"),
-        Path::new(&out_dir).join("libstdbuf.so"),
-    )
-    .unwrap();
+            name.starts_with("liblibstdbuf") && name.ends_with(platform::DYLIB_EXT)
+        })
+        .expect("libstdbuf not found");
+
+    fs::copy(libstdbuf.path(), out_dir.join("libstdbuf.so")).unwrap();
 }