blkar 7.2.7

Multithreaded archiver offering bit rot protection and sector level recoverability
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85

#![allow(dead_code)]
use crate::file_reader::FileReader;
use crate::general_error::Error;
use crate::stdin_error::{to_err, StdinError};
use std::fs::Metadata;
use std::io::Read;
use std::io::SeekFrom;

const READ_RETRIES: usize = 5;

#[must_use]
pub struct ReadResult {
    pub len_read: usize,
    pub eof_seen: bool,
}

pub enum ReaderType {
    File(FileReader),
    Stdin(std::io::Stdin),
}

pub struct Reader {
    reader: ReaderType,
}

impl Reader {
    pub fn new(reader: ReaderType) -> Reader {
        Reader { reader }
    }

    pub fn read(&mut self, buf: &mut [u8]) -> Result<ReadResult, Error> {
        match self.reader {
            ReaderType::File(ref mut f) => f.read(buf),
            ReaderType::Stdin(ref mut s) => {
                let mut len_read = 0;
                let mut tries = 0;
                while len_read < buf.len() && tries < READ_RETRIES {
                    match s.read(&mut buf[len_read..]) {
                        Ok(len) => {
                            len_read += len;
                        }
                        Err(e) => {
                            return Err(to_err(StdinError::new(e.kind())));
                        }
                    }

                    tries += 1;
                }

                Ok(ReadResult {
                    len_read,
                    eof_seen: len_read < buf.len(),
                })
            }
        }
    }

    pub fn metadata(&self) -> Option<Result<Metadata, Error>> {
        match self.reader {
            ReaderType::File(ref f) => Some(f.metadata()),
            ReaderType::Stdin(_) => None,
        }
    }

    pub fn get_file_size(&mut self) -> Option<Result<u64, Error>> {
        match self.reader {
            ReaderType::File(ref mut f) => Some(f.get_file_size()),
            ReaderType::Stdin(_) => None,
        }
    }

    pub fn seek(&mut self, pos: SeekFrom) -> Option<Result<u64, Error>> {
        match self.reader {
            ReaderType::Stdin(_) => None,
            ReaderType::File(ref mut f) => Some(f.seek(pos)),
        }
    }

    pub fn cur_pos(&mut self) -> Option<Result<u64, Error>> {
        match self.reader {
            ReaderType::File(ref mut f) => Some(f.cur_pos()),
            ReaderType::Stdin(_) => None,
        }
    }
}