Merge pull request #411 from JRF63/ftw-chown

chown implementation

Author: jgarzik

tree/chgrp.rs

@@ -9,37 +9,17 @@
 
 mod common;
 
-use self::common::error_string;
+use self::common::{chown_traverse, error_string, ChangeOwnershipArgs};
 use clap::Parser;
 use gettextrs::{bind_textdomain_codeset, gettext, setlocale, textdomain, LocaleCategory};
-use std::{cell::RefCell, ffi::CString, io, os::unix::fs::MetadataExt};
+use std::{ffi::CString, io};
 
 /// chgrp - change file group ownership
 #[derive(Parser)]
 #[command(version, about, disable_help_flag = true)]
 struct Args {
-    #[arg(long, action = clap::ArgAction::HelpLong)] // Bec. help clashes with -h
-    help: Option<bool>,
-
-    /// Change symbolic links, rather than the files they point to
-    #[arg(short = 'h', long, default_value_t = false)]
-    no_derereference: bool,
-
-    /// Follow command line symlinks during -R recursion
-    #[arg(short = 'H', overrides_with_all = ["follow_cli", "follow_symlinks", "follow_none"])]
-    follow_cli: bool,
-
-    /// Follow symlinks during -R recursion
-    #[arg(short = 'L', overrides_with_all = ["follow_cli", "follow_symlinks", "follow_none"])]
-    follow_symlinks: bool,
-
-    /// Never follow symlinks during -R recursion
-    #[arg(short = 'P', overrides_with_all = ["follow_cli", "follow_symlinks", "follow_none"], default_value_t = true)]
-    follow_none: bool,
-
-    /// Recursively change groups of directories and their contents
-    #[arg(short, short_alias = 'R', long)]
-    recurse: bool,
+    #[command(flatten)]
+    delegate: ChangeOwnershipArgs,
 
     /// A group name from the group database or a numeric group ID
     group: String,
@@ -48,89 +28,6 @@ struct Args {
     files: Vec<String>,
 }
 
-fn chgrp_file(filename: &str, gid: Option<u32>, args: &Args) -> bool {
-    let recurse = args.recurse;
-    let no_derereference = args.no_derereference;
-
-    let terminate = RefCell::new(false);
-
-    ftw::traverse_directory(
-        filename,
-        |entry| {
-            if *terminate.borrow() {
-                return Ok(false);
-            }
-
-            let md = entry.metadata().unwrap();
-
-            // According to the spec:
-            // "The user ID of the file shall be used as the owner argument."
-            let uid = md.uid();
-
-            // Don't change the group ID if the group argument is empty
-            let gid = gid.unwrap_or(libc::gid_t::MAX);
-
-            let ret = unsafe {
-                libc::fchownat(
-                    entry.dir_fd(),
-                    entry.file_name().as_ptr(),
-                    uid,
-                    gid,
-                    // Default is to change the file that the symbolic link points to unless the
-                    // -h flag is specified.
-                    if no_derereference {
-                        libc::AT_SYMLINK_NOFOLLOW
-                    } else {
-                        0
-                    },
-                )
-            };
-            if ret != 0 {
-                let e = io::Error::last_os_error();
-                let err_str = match e.kind() {
-                    io::ErrorKind::PermissionDenied => {
-                        gettext!("cannot access '{}': {}", entry.path(), error_string(&e))
-                    }
-                    _ => {
-                        gettext!("changing group of '{}': {}", entry.path(), error_string(&e))
-                    }
-                };
-                eprintln!("chgrp: {}", err_str);
-                *terminate.borrow_mut() = true;
-                return Err(());
-            }
-
-            Ok(recurse)
-        },
-        |_| Ok(()), // Do nothing on `postprocess_dir`
-        |entry, error| {
-            let e = error.inner();
-            let err_str = match e.kind() {
-                io::ErrorKind::PermissionDenied => {
-                    gettext!(
-                        "cannot read directory '{}': {}",
-                        entry.path(),
-                        error_string(&e)
-                    )
-                }
-                _ => {
-                    gettext!("changing group of '{}': {}", entry.path(), error_string(&e))
-                }
-            };
-            eprintln!("chgrp: {}", err_str);
-            *terminate.borrow_mut() = true;
-        },
-        ftw::TraverseDirectoryOpts {
-            follow_symlinks_on_args: args.follow_cli,
-            follow_symlinks: args.follow_symlinks,
-            ..Default::default()
-        },
-    );
-
-    let failed = *terminate.borrow();
-    !failed
-}
-
 // lookup string group by name, or parse numeric group ID
 fn parse_group(group: &str) -> Result<Option<u32>, String> {
     // empty strings are accepted without errors
@@ -155,13 +52,37 @@ fn parse_group(group: &str) -> Result<Option<u32>, String> {
     }
 }
 
+fn err_handler(e: io::Error, path: ftw::DisplayablePath) {
+    let err_str = match e.kind() {
+        io::ErrorKind::PermissionDenied => {
+            gettext!("cannot read directory '{}': {}", path, error_string(&e))
+        }
+        _ => {
+            gettext!("changing group of '{}': {}", path, error_string(&e))
+        }
+    };
+    eprintln!("chgrp: {}", err_str);
+}
+
+fn chown_err_handler(e: io::Error, path: ftw::DisplayablePath) {
+    let err_str = match e.kind() {
+        io::ErrorKind::PermissionDenied => {
+            gettext!("cannot access '{}': {}", path, error_string(&e))
+        }
+        _ => {
+            gettext!("changing group of '{}': {}", path, error_string(&e))
+        }
+    };
+    eprintln!("chgrp: {}", err_str);
+}
+
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     // parse command line arguments
     let mut args = Args::parse();
 
     // Enable `no_derereference` if `-R` is enabled without either `-H` or `-L`
-    if args.recurse && !(args.follow_cli || args.follow_symlinks) {
-        args.no_derereference = true;
+    if args.delegate.recurse && !(args.delegate.follow_cli || args.delegate.follow_symlinks) {
+        args.delegate.no_dereference = true;
     }
 
     // initialize translations
@@ -182,7 +103,14 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     // apply the group to each file
     for filename in &args.files {
-        let success = chgrp_file(filename, gid, &args);
+        let success = chown_traverse(
+            filename,
+            None,
+            gid,
+            &args.delegate,
+            err_handler,
+            chown_err_handler,
+        );
         if !success {
             exit_code = 1;
         }