70 lines
1.9 KiB
Rust
70 lines
1.9 KiB
Rust
//! Test using `Bytes` with an allocator that hands out "odd" pointers for
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//! vectors (pointers where the LSB is set).
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#![cfg(not(miri))] // Miri does not support custom allocators (also, Miri is "odd" by default with 50% chance)
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use std::alloc::{GlobalAlloc, Layout, System};
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use std::ptr;
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use bytes::Bytes;
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#[global_allocator]
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static ODD: Odd = Odd;
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struct Odd;
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unsafe impl GlobalAlloc for Odd {
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unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
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if layout.align() == 1 && layout.size() > 0 {
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// Allocate slightly bigger so that we can offset the pointer by 1
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let size = layout.size() + 1;
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let new_layout = match Layout::from_size_align(size, 1) {
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Ok(layout) => layout,
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Err(_err) => return ptr::null_mut(),
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};
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let ptr = System.alloc(new_layout);
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if !ptr.is_null() {
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let ptr = ptr.offset(1);
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ptr
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} else {
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ptr
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}
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} else {
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System.alloc(layout)
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}
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}
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unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
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if layout.align() == 1 && layout.size() > 0 {
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let size = layout.size() + 1;
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let new_layout = match Layout::from_size_align(size, 1) {
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Ok(layout) => layout,
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Err(_err) => std::process::abort(),
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};
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System.dealloc(ptr.offset(-1), new_layout);
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} else {
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System.dealloc(ptr, layout);
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}
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}
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}
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#[test]
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fn sanity_check_odd_allocator() {
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let vec = vec![33u8; 1024];
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let p = vec.as_ptr() as usize;
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assert!(p & 0x1 == 0x1, "{:#b}", p);
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}
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#[test]
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fn test_bytes_from_vec_drop() {
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let vec = vec![33u8; 1024];
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let _b = Bytes::from(vec);
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}
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#[test]
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fn test_bytes_clone_drop() {
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let vec = vec![33u8; 1024];
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let b1 = Bytes::from(vec);
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let _b2 = b1.clone();
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}
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