peekbufread 0.1.6

Implements a peekable std::io::Read with support for checkpoints
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
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129

use crate::PeekRead;
use rand::prelude::*;
use std::io::Cursor;
use test::Bencher;

const LEN: usize = 1024;

fn generate_1m() -> Box<[u8; LEN * 1024]> {
    let mut result = Box::new([0; LEN * 1024]);

    let mut rng = thread_rng();
    for i in 0..1024 {
        rng.fill(&mut result[i * LEN..(i + 1) * LEN]);
    }

    return result;
}

#[bench]
fn read_exact_normal(bench: &mut Bencher) {
    let data = generate_1m();

    bench.iter(move || {
        let mut read = Cursor::new(data.as_ref());
        let mut buf = [0; LEN];
        for _ in 0..data.len() / 1024 {
            use std::io::Read;
            // Don't optimize me away
            let result = read.read_exact(&mut buf);
            assert!(result.is_ok());
            test::black_box(result).unwrap();
        }
    });
}

#[bench]
fn read_exact_normal_peekread(bench: &mut Bencher) {
    let data = generate_1m();

    bench.iter(move || {
        let mut read = PeekRead::new(Cursor::new(data.as_ref()));
        let mut buf = [0; LEN];
        for _ in 0..data.len() / 1024 {
            use std::io::Read;
            // Don't optimize me away
            let result = read.read_exact(&mut buf);
            assert!(result.is_ok());
            test::black_box(result).unwrap();
        }
    });
}

#[cfg(feature = "checkpoint")]
#[bench]
fn read_exact_with_checkpoint_peekread(bench: &mut Bencher) {
    let data = generate_1m();

    bench.iter(move || {
        let mut read = PeekRead::new(Cursor::new(data.as_ref()));
        read.checkpoint(|read| -> Result<(), ()> {
            let mut buf = [0; LEN];
            for _ in 0..data.len() / 1024 {
                use std::io::Read;
                let result = read.read_exact(&mut buf);
                assert!(result.is_ok());
                test::black_box(result).unwrap();
            }

            Ok(())
        })
        .unwrap();
    });
}

#[bench]
fn read_normal(bench: &mut Bencher) {
    let data = generate_1m();

    bench.iter(move || {
        let mut read = Cursor::new(data.as_ref());
        let mut buf = [0; LEN];
        for _ in 0..data.len() / 1024 {
            use std::io::Read;
            // Don't optimize me away
            let result = read.read(&mut buf);
            assert!(result.is_ok());
            assert_eq!(LEN, result.unwrap());
        }
    });
}

#[bench]
fn read_normal_peekread(bench: &mut Bencher) {
    let data = generate_1m();

    bench.iter(move || {
        let mut read = PeekRead::new(Cursor::new(data.as_ref()));
        let mut buf = [0; LEN];
        for _ in 0..data.len() / 1024 {
            use std::io::Read;
            // Don't optimize me away
            let result = read.read(&mut buf);
            assert!(result.is_ok());
            assert_eq!(LEN, result.unwrap());
        }
    });
}

#[cfg(feature = "checkpoint")]
#[bench]
fn read_with_checkpoint_peekread(bench: &mut Bencher) {
    let data = generate_1m();

    bench.iter(move || {
        let mut read = PeekRead::new(Cursor::new(data.as_ref()));
        read.checkpoint(|read| -> Result<(), ()> {
            let mut buf = [0; LEN];
            for _ in 0..data.len() / 1024 {
                use std::io::Read;
                let result = read.read(&mut buf);
                assert!(result.is_ok());
                assert_eq!(LEN, result.unwrap());
            }

            Ok(())
        })
        .unwrap();
    });
}