chroot-realpath: Add error context (#410360)

# This file is automatically @generated by Cargo.

# It is not intended for manual editing.

version = 3

version = 4

[[package]]

name = "anyhow"

version = "1.0.98"

source = "registry+https://github.com/rust-lang/crates.io-index"

checksum = "e16d2d3311acee920a9eb8d33b8cbc1787ce4a264e85f964c2404b969bdcd487"

[[package]]

name = "chroot-realpath"

version = "0.1.0"

dependencies = [

 "anyhow",

]

edition = "2021"

[dependencies]

anyhow = "1.0.98"

[profile.release]

opt-level = "z"

use std::env;

use std::io::{stdout, Error, ErrorKind, Write};

use std::io::{stdout, Write};

use std::os::unix::ffi::OsStrExt;

use std::os::unix::fs;

fn main() -> std::io::Result<()> {

use anyhow::{bail, Context, Result};

fn main() -> Result<()> {

    let args: Vec<String> = env::args().collect();

    if args.len() != 3 {

        return Err(Error::new(

            ErrorKind::InvalidInput,

            format!("Usage: {} <chroot> <path>", args[0]),

        ));

        bail!("Usage: {} <chroot> <path>", args[0]);

    }

    fs::chroot(&args[1])?;

    std::env::set_current_dir("/")?;

    fs::chroot(&args[1]).context("Failed to chroot")?;

    std::env::set_current_dir("/").context("Failed to change directory")?;

    let path = std::fs::canonicalize(&args[2])?;

    let path = std::fs::canonicalize(&args[2])

        .with_context(|| format!("Failed to canonicalize {}", args[2]))?;

    stdout().write_all(path.into_os_string().as_bytes())?;

    stdout()

        .write_all(path.into_os_string().as_bytes())

        .context("Failed to write output")?;

    Ok(())

}