wasmi/src/memory/vec_bytebuf.rs

//! An implementation of `ByteBuf` based on a plain `Vec`.

use alloc::prelude::v1::*;

pub struct ByteBuf {
    buf: Vec<u8>,
}

impl ByteBuf {
    pub fn new(len: usize) -> Result<Self, &'static str> {
        let mut buf = Vec::new();
        buf.resize(len, 0u8);
        Ok(Self { buf })
    }

    pub fn realloc(&mut self, new_len: usize) -> Result<(), &'static str> {
        self.buf.resize(new_len, 0u8);
        Ok(())
    }

    pub fn len(&self) -> usize {
        self.buf.len()
    }

    pub fn as_slice(&self) -> &[u8] {
        self.buf.as_ref()
    }

    pub fn as_slice_mut(&mut self) -> &mut [u8] {
        self.buf.as_mut()
    }

    pub fn erase(&mut self) -> Result<(), &'static str> {
        for v in &mut self.buf {
            *v = 0;
        }
        Ok(())
    }
}