1
Fork 0
mirror of https://github.com/RGBCube/uutils-coreutils synced 2025-07-31 21:17:46 +00:00
This commit is contained in:
kwantam 2015-04-30 18:44:31 -04:00
parent 9a806346a9
commit 4390e4ffa6

View file

@ -1,5 +1,5 @@
#![crate_name = "tac"]
#![feature(collections, core, old_io, old_path, rustc_private)]
#![feature(rustc_private)]
/*
* This file is part of the uutils coreutils package.
@ -13,7 +13,8 @@
extern crate getopts;
extern crate libc;
use std::old_io as io;
use std::fs::File;
use std::io::{stdin, stdout, BufReader, Read, Stdout, Write};
#[path = "../common/util.rs"]
#[macro_use]
@ -23,8 +24,6 @@ static NAME: &'static str = "tac";
static VERSION: &'static str = "1.0.0";
pub fn uumain(args: Vec<String>) -> i32 {
let program = args[0].clone();
let opts = [
getopts::optflag("b", "before", "attach the separator before instead of after"),
getopts::optflag("r", "regex", "interpret the sequence as a regular expression (NOT IMPLEMENTED)"),
@ -32,7 +31,7 @@ pub fn uumain(args: Vec<String>) -> i32 {
getopts::optflag("h", "help", "display this help and exit"),
getopts::optflag("V", "version", "output version information and exit")
];
let matches = match getopts::getopts(args.tail(), &opts) {
let matches = match getopts::getopts(&args[1..], &opts) {
Ok(m) => m,
Err(f) => crash!(1, "{}", f)
};
@ -40,7 +39,7 @@ pub fn uumain(args: Vec<String>) -> i32 {
println!("tac {}", VERSION);
println!("");
println!("Usage:");
println!(" {0} [OPTION]... [FILE]...", program);
println!(" {0} [OPTION]... [FILE]...", &args[0][..]);
println!("");
print!("{}", getopts::usage("Write each file to standard output, last line first.", &opts));
} else if matches.opt_present("version") {
@ -63,41 +62,86 @@ pub fn uumain(args: Vec<String>) -> i32 {
} else {
matches.free
};
tac(files, before, regex, separator.as_slice());
tac(files, before, regex, &separator[..]);
}
0
}
fn tac(filenames: Vec<String>, before: bool, _: bool, separator: &str) {
for filename in filenames.into_iter() {
let mut file = io::BufferedReader::new(
if filename.as_slice() == "-" {
Box::new(io::stdio::stdin_raw()) as Box<Reader>
let mut out = stdout();
let sbytes = separator.as_bytes();
let slen = sbytes.len();
for filename in filenames.iter() {
let mut file = BufReader::new(
if filename == "-" {
Box::new(stdin()) as Box<Read>
} else {
let r = crash_if_err!(1, io::File::open(&Path::new(filename)));
Box::new(r) as Box<Reader>
match File::open(filename) {
Ok(f) => Box::new(f) as Box<Read>,
Err(e) => {
show_warning!("failed to open '{}' for reading: {}", filename, e);
continue;
},
}
});
let mut data = Vec::new();
match file.read_to_end(&mut data) {
Err(e) => {
show_warning!("failed to read '{}': {}", filename, e);
continue;
},
Ok(_) => (),
};
// find offsets in string of all separators
let mut offsets = Vec::new();
let mut i = 0;
loop {
if i + slen > data.len() {
break;
}
if &data[i..i+slen] == sbytes {
offsets.push(i);
i += slen;
} else {
i += 1;
}
);
let mut data = crash_if_err!(1, file.read_to_string());
if data.as_slice().ends_with("\n") {
// removes blank line that is inserted otherwise
let mut buf = data.to_string();
let len = buf.len();
buf.truncate(len - 1);
data = buf.to_string();
}
let split_vec: Vec<&str> = data.as_slice().split_str(separator).collect();
let rev: String = split_vec.iter().rev().fold(String::new(), |mut a, &b| {
if before {
a.push_str(separator);
a.push_str(b);
drop(i);
// if there isn't a separator at the end of the file, fake it
if offsets.len() == 0 || *offsets.last().unwrap() < data.len() - slen {
offsets.push(data.len());
}
let mut prev = *offsets.last().unwrap();
let mut start = true;
for off in offsets.iter().rev().skip(1) {
// correctly handle case of no final separator in file
if start && prev == data.len() {
show_line(&mut out, &[], &data[*off+slen..prev], before);
start = false;
} else {
a.push_str(b);
a.push_str(separator);
show_line(&mut out, sbytes, &data[*off+slen..prev], before);
}
a
});
print!("{}", rev);
prev = *off;
}
show_line(&mut out, sbytes, &data[0..prev], before);
}
}
fn show_line(out: &mut Stdout, sep: &[u8], dat: &[u8], before: bool) {
if before {
out.write_all(sep).unwrap_or_else(|e| crash!(1, "failed to write to stdout: {}", e));
}
out.write_all(dat).unwrap_or_else(|e| crash!(1, "failed to write to stdout: {}", e));
if !before {
out.write_all(sep).unwrap_or_else(|e| crash!(1, "failed to write to stdout: {}", e));
}
}