abin 0.1.6

A library for working with binaries and strings. The library tries to avoid heap-allocations / memory-copy whenever possible by automatically choosing a reasonable strategy: stack for small binaries; static-lifetime-binary or reference-counting.
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

use std::alloc::System;

use stats_alloc::{StatsAlloc, INSTRUMENTED_SYSTEM};

use abin::{BinFactory, NewBin, NewSBin};
use utils::*;

#[global_allocator]
static GLOBAL: &StatsAlloc<System> = &INSTRUMENTED_SYSTEM;

pub mod utils;

// that's the maximum that fits onto the stack.
const FITS_STACK: usize = 3 * core::mem::size_of::<usize>() - 1;

#[test]
fn stack_memory() {
    mem_scoped(&GLOBAL, &MaNoLeak, || {
        copy_from_slice::<NewBin>();
        copy_from_slice::<NewSBin>();
        from_vec::<NewBin>();
        from_vec::<NewSBin>();
        from_iter::<NewBin>();
        from_iter::<NewSBin>();
    });
}

/// rc also uses stack and does not allocate for small binaries.
fn copy_from_slice<T: BinFactory>() {
    let slice = [15u8; FITS_STACK];
    mem_scoped(&GLOBAL, &MaNoAllocNoDealloc, || {
        T::copy_from_slice(&slice);
    });
}

/// vec also uses stack and does not allocate for small binaries.
fn from_vec<T: BinFactory>() {
    let slice = [15u8; FITS_STACK];
    let vec = slice.to_vec();
    mem_scoped(&GLOBAL, &MaNoAllocNoReAlloc, || {
        T::from_given_vec(vec);
    });
}

/// iter also uses stack and does not allocate for small binaries.
fn from_iter<T: BinFactory>() {
    let slice = [15u8; FITS_STACK];
    let vec = Vec::from(&slice as &[u8]);
    mem_scoped(&GLOBAL, &MaNoAllocNoReAlloc, || {
        T::from_iter(vec);
    });
}