| use nix::sys::mman::{mmap, MapFlags, ProtFlags}; |
| use std::num::NonZeroUsize; |
| |
| #[test] |
| fn test_mmap_anonymous() { |
| unsafe { |
| let ptr = mmap( |
| None, |
| NonZeroUsize::new(1).unwrap(), |
| ProtFlags::PROT_READ | ProtFlags::PROT_WRITE, |
| MapFlags::MAP_PRIVATE | MapFlags::MAP_ANONYMOUS, |
| -1, |
| 0, |
| ) |
| .unwrap() as *mut u8; |
| assert_eq!(*ptr, 0x00u8); |
| *ptr = 0xffu8; |
| assert_eq!(*ptr, 0xffu8); |
| } |
| } |
| |
| #[test] |
| #[cfg(any(target_os = "linux", target_os = "netbsd"))] |
| fn test_mremap_grow() { |
| use nix::libc::{c_void, size_t}; |
| use nix::sys::mman::{mremap, MRemapFlags}; |
| |
| const ONE_K: size_t = 1024; |
| let one_k_non_zero = NonZeroUsize::new(ONE_K).unwrap(); |
| |
| let slice: &mut [u8] = unsafe { |
| let mem = mmap( |
| None, |
| one_k_non_zero, |
| ProtFlags::PROT_READ | ProtFlags::PROT_WRITE, |
| MapFlags::MAP_ANONYMOUS | MapFlags::MAP_PRIVATE, |
| -1, |
| 0, |
| ) |
| .unwrap(); |
| std::slice::from_raw_parts_mut(mem as *mut u8, ONE_K) |
| }; |
| assert_eq!(slice[ONE_K - 1], 0x00); |
| slice[ONE_K - 1] = 0xFF; |
| assert_eq!(slice[ONE_K - 1], 0xFF); |
| |
| let slice: &mut [u8] = unsafe { |
| #[cfg(target_os = "linux")] |
| let mem = mremap( |
| slice.as_mut_ptr() as *mut c_void, |
| ONE_K, |
| 10 * ONE_K, |
| MRemapFlags::MREMAP_MAYMOVE, |
| None, |
| ) |
| .unwrap(); |
| #[cfg(target_os = "netbsd")] |
| let mem = mremap( |
| slice.as_mut_ptr() as *mut c_void, |
| ONE_K, |
| 10 * ONE_K, |
| MRemapFlags::MAP_REMAPDUP, |
| None, |
| ) |
| .unwrap(); |
| std::slice::from_raw_parts_mut(mem as *mut u8, 10 * ONE_K) |
| }; |
| |
| // The first KB should still have the old data in it. |
| assert_eq!(slice[ONE_K - 1], 0xFF); |
| |
| // The additional range should be zero-init'd and accessible. |
| assert_eq!(slice[10 * ONE_K - 1], 0x00); |
| slice[10 * ONE_K - 1] = 0xFF; |
| assert_eq!(slice[10 * ONE_K - 1], 0xFF); |
| } |
| |
| #[test] |
| #[cfg(any(target_os = "linux", target_os = "netbsd"))] |
| // Segfaults for unknown reasons under QEMU for 32-bit targets |
| #[cfg_attr(all(target_pointer_width = "32", qemu), ignore)] |
| fn test_mremap_shrink() { |
| use nix::libc::{c_void, size_t}; |
| use nix::sys::mman::{mremap, MRemapFlags}; |
| use std::num::NonZeroUsize; |
| |
| const ONE_K: size_t = 1024; |
| let ten_one_k = NonZeroUsize::new(10 * ONE_K).unwrap(); |
| let slice: &mut [u8] = unsafe { |
| let mem = mmap( |
| None, |
| ten_one_k, |
| ProtFlags::PROT_READ | ProtFlags::PROT_WRITE, |
| MapFlags::MAP_ANONYMOUS | MapFlags::MAP_PRIVATE, |
| -1, |
| 0, |
| ) |
| .unwrap(); |
| std::slice::from_raw_parts_mut(mem as *mut u8, ONE_K) |
| }; |
| assert_eq!(slice[ONE_K - 1], 0x00); |
| slice[ONE_K - 1] = 0xFF; |
| assert_eq!(slice[ONE_K - 1], 0xFF); |
| |
| let slice: &mut [u8] = unsafe { |
| let mem = mremap( |
| slice.as_mut_ptr() as *mut c_void, |
| ten_one_k.into(), |
| ONE_K, |
| MRemapFlags::empty(), |
| None, |
| ) |
| .unwrap(); |
| // Since we didn't supply MREMAP_MAYMOVE, the address should be the |
| // same. |
| assert_eq!(mem, slice.as_mut_ptr() as *mut c_void); |
| std::slice::from_raw_parts_mut(mem as *mut u8, ONE_K) |
| }; |
| |
| // The first KB should still be accessible and have the old data in it. |
| assert_eq!(slice[ONE_K - 1], 0xFF); |
| } |