1 files changed, 49 insertions, 10 deletions

diff --git a/src/bootstrap/install.rs b/src/bootstrap/install.rs
index b62aa9992..500b20b86 100644
--- a/src/bootstrap/install.rs
+++ b/src/bootstrap/install.rs
@@ -45,6 +45,23 @@ fn sanitize_sh(path: &Path) -> String {
     }
 }
 
+fn is_dir_writable_for_user(dir: &PathBuf) -> bool {
+    let tmp = dir.join(".tmp");
+    match fs::create_dir_all(&tmp) {
+        Ok(_) => {
+            fs::remove_dir_all(tmp).unwrap();
+            true
+        }
+        Err(e) => {
+            if e.kind() == std::io::ErrorKind::PermissionDenied {
+                false
+            } else {
+                panic!("Failed the write access check for the current user. {}", e);
+            }
+        }
+    }
+}
+
 fn install_sh(
     builder: &Builder<'_>,
     package: &str,
@@ -56,6 +73,28 @@ fn install_sh(
 
     let prefix = default_path(&builder.config.prefix, "/usr/local");
     let sysconfdir = prefix.join(default_path(&builder.config.sysconfdir, "/etc"));
+    let destdir_env = env::var_os("DESTDIR").map(PathBuf::from);
+
+    // Sanity checks on the write access of user.
+    //
+    // When the `DESTDIR` environment variable is present, there is no point to
+    // check write access for `prefix` and `sysconfdir` individually, as they
+    // are combined with the path from the `DESTDIR` environment variable. In
+    // this case, we only need to check the `DESTDIR` path, disregarding the
+    // `prefix` and `sysconfdir` paths.
+    if let Some(destdir) = &destdir_env {
+        assert!(is_dir_writable_for_user(destdir), "User doesn't have write access on DESTDIR.");
+    } else {
+        assert!(
+            is_dir_writable_for_user(&prefix),
+            "User doesn't have write access on `install.prefix` path in the `config.toml`.",
+        );
+        assert!(
+            is_dir_writable_for_user(&sysconfdir),
+            "User doesn't have write access on `install.sysconfdir` path in `config.toml`."
+        );
+    }
+
     let datadir = prefix.join(default_path(&builder.config.datadir, "share"));
     let docdir = prefix.join(default_path(&builder.config.docdir, "share/doc/rust"));
     let mandir = prefix.join(default_path(&builder.config.mandir, "share/man"));
@@ -68,13 +107,13 @@ fn install_sh(
     let mut cmd = Command::new(SHELL);
     cmd.current_dir(&empty_dir)
         .arg(sanitize_sh(&tarball.decompressed_output().join("install.sh")))
-        .arg(format!("--prefix={}", prepare_dir(prefix)))
-        .arg(format!("--sysconfdir={}", prepare_dir(sysconfdir)))
-        .arg(format!("--datadir={}", prepare_dir(datadir)))
-        .arg(format!("--docdir={}", prepare_dir(docdir)))
-        .arg(format!("--bindir={}", prepare_dir(bindir)))
-        .arg(format!("--libdir={}", prepare_dir(libdir)))
-        .arg(format!("--mandir={}", prepare_dir(mandir)))
+        .arg(format!("--prefix={}", prepare_dir(&destdir_env, prefix)))
+        .arg(format!("--sysconfdir={}", prepare_dir(&destdir_env, sysconfdir)))
+        .arg(format!("--datadir={}", prepare_dir(&destdir_env, datadir)))
+        .arg(format!("--docdir={}", prepare_dir(&destdir_env, docdir)))
+        .arg(format!("--bindir={}", prepare_dir(&destdir_env, bindir)))
+        .arg(format!("--libdir={}", prepare_dir(&destdir_env, libdir)))
+        .arg(format!("--mandir={}", prepare_dir(&destdir_env, mandir)))
         .arg("--disable-ldconfig");
     builder.run(&mut cmd);
     t!(fs::remove_dir_all(&empty_dir));
@@ -84,16 +123,16 @@ fn default_path(config: &Option<PathBuf>, default: &str) -> PathBuf {
     config.as_ref().cloned().unwrap_or_else(|| PathBuf::from(default))
 }
 
-fn prepare_dir(mut path: PathBuf) -> String {
+fn prepare_dir(destdir_env: &Option<PathBuf>, mut path: PathBuf) -> String {
     // The DESTDIR environment variable is a standard way to install software in a subdirectory
     // while keeping the original directory structure, even if the prefix or other directories
     // contain absolute paths.
     //
     // More information on the environment variable is available here:
     // https://www.gnu.org/prep/standards/html_node/DESTDIR.html
-    if let Some(destdir) = env::var_os("DESTDIR").map(PathBuf::from) {
+    if let Some(destdir) = destdir_env {
         let without_destdir = path.clone();
-        path = destdir;
+        path = destdir.clone();
         // Custom .join() which ignores disk roots.
         for part in without_destdir.components() {
             if let Component::Normal(s) = part {