use serde::Serialize;
use sha2::{Digest, Sha256};
use std::fs::File;
use std::fs::{read_link, symlink_metadata};
use std::io::{BufReader, Read};
use std::os::linux::fs::MetadataExt;
use std::path::{Path, PathBuf};
const BUF_SIZE: usize = 1024 * 1024;
#[derive(Serialize, Debug)]
pub struct ManifestEntry {
path: String,
#[serde(with = "mode")]
mode: u32,
mtime: i64,
mtime_nsec: i64,
nlink: u64,
size: Option<u64>,
sha256: Option<String>,
target: Option<PathBuf>,
}
impl ManifestEntry {
pub fn new(path: &Path) -> std::io::Result<Self> {
let m = symlink_metadata(path)?;
let hash = if m.is_file() {
Some(file_checksum(path)?)
} else {
None
};
let target = if m.file_type().is_symlink() {
Some(read_link(path)?)
} else {
None
};
Ok(Self {
path: path.to_string_lossy().into_owned(),
mode: m.st_mode(),
mtime: m.st_mtime(),
mtime_nsec: m.st_mtime_nsec(),
nlink: m.st_nlink(),
size: if m.is_dir() { None } else { Some(m.st_size()) },
sha256: hash,
target,
})
}
}
fn file_checksum(path: &Path) -> std::io::Result<String> {
let mut hasher = Sha256::new();
let file = File::open(path)?;
let mut reader = BufReader::new(file);
let mut buf = vec![0; BUF_SIZE];
loop {
let n = reader.read(&mut buf)?;
if n == 0 {
break;
}
hasher.update(&buf[..n]);
}
let hash = hasher.finalize();
Ok(format!("{:x}", hash))
}
mod mode {
use serde::{self, Serializer};
pub fn serialize<S>(mode: &u32, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let s = unix_mode::to_string(*mode);
serializer.serialize_str(&s)
}
}