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use crate::alloc;
use alloc::{Alloc, AllocErr};
use solana_rbpf::aligned_memory::AlignedMemory;
use std::alloc::Layout;
#[derive(Debug)]
pub struct BpfAllocator {
heap: AlignedMemory,
start: u64,
len: u64,
pos: u64,
}
impl BpfAllocator {
pub fn new(heap: AlignedMemory, virtual_address: u64) -> Self {
let len = heap.len() as u64;
Self {
heap,
start: virtual_address,
len,
pos: 0,
}
}
}
impl Alloc for BpfAllocator {
fn alloc(&mut self, layout: Layout) -> Result<u64, AllocErr> {
let bytes_to_align = (self.pos as *const u8).align_offset(layout.align()) as u64;
if self
.pos
.saturating_add(layout.size() as u64)
.saturating_add(bytes_to_align)
<= self.len
{
self.pos += bytes_to_align;
let addr = self.start + self.pos;
self.pos += layout.size() as u64;
Ok(addr)
} else {
Err(AllocErr)
}
}
fn dealloc(&mut self, _addr: u64, _layout: Layout) {
}
}