rust-base64/examples/base64.rs

90 lines
2.4 KiB
Rust

use std::fs::File;
use std::io::{self, Read};
use std::path::PathBuf;
use std::process;
use std::str::FromStr;
use base64::{read, write};
use structopt::StructOpt;
#[derive(Debug, StructOpt)]
enum CharacterSet {
Standard,
UrlSafe,
}
impl Default for CharacterSet {
fn default() -> Self {
CharacterSet::Standard
}
}
impl Into<base64::Config> for CharacterSet {
fn into(self) -> base64::Config {
match self {
CharacterSet::Standard => base64::STANDARD,
CharacterSet::UrlSafe => base64::URL_SAFE,
}
}
}
impl FromStr for CharacterSet {
type Err = String;
fn from_str(s: &str) -> Result<CharacterSet, String> {
match s {
"standard" => Ok(CharacterSet::Standard),
"urlsafe" => Ok(CharacterSet::UrlSafe),
_ => Err(format!("charset '{}' unrecognized", s)),
}
}
}
/// Base64 encode or decode FILE (or standard input), to standard output.
#[derive(Debug, StructOpt)]
struct Opt {
/// decode data
#[structopt(short = "d", long = "decode")]
decode: bool,
/// The character set to choose. Defaults to the standard base64 character set.
/// Supported character sets include "standard" and "urlsafe".
#[structopt(long = "charset")]
charset: Option<CharacterSet>,
/// The file to encode/decode.
#[structopt(parse(from_os_str))]
file: Option<PathBuf>,
}
fn main() {
let opt = Opt::from_args();
let stdin;
let mut input: Box<dyn Read> = match opt.file {
None => {
stdin = io::stdin();
Box::new(stdin.lock())
}
Some(ref f) if f.as_os_str() == "-" => {
stdin = io::stdin();
Box::new(stdin.lock())
}
Some(f) => Box::new(File::open(f).unwrap()),
};
let config = opt.charset.unwrap_or_default().into();
let stdout = io::stdout();
let mut stdout = stdout.lock();
let r = if opt.decode {
let mut decoder = read::DecoderReader::new(&mut input, config);
io::copy(&mut decoder, &mut stdout)
} else {
let mut encoder = write::EncoderWriter::new(&mut stdout, config);
io::copy(&mut input, &mut encoder)
};
if let Err(e) = r {
eprintln!(
"Base64 {} failed with {}",
if opt.decode { "decode" } else { "encode" },
e
);
process::exit(1);
}
}