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use nix::Error;
use nix::libc::{c_void, size_t};
use nix::sys::mman::{mmap, MapFlags, ProtFlags};
#[cfg(target_os = "linux")]
use nix::sys::mman::{mremap, MRemapFlags};
#[test]
fn test_mmap_anonymous() {
let ref mut byte = unsafe {
let ptr = mmap(std::ptr::null_mut(), 1,
ProtFlags::PROT_READ | ProtFlags::PROT_WRITE,
MapFlags::MAP_PRIVATE | MapFlags::MAP_ANONYMOUS, -1, 0)
.unwrap();
*(ptr as * mut u8)
};
assert_eq !(*byte, 0x00u8);
*byte = 0xffu8;
assert_eq !(*byte, 0xffu8);
}
#[test]
#[cfg(target_os = "linux")]
fn test_mremap_grow() {
const ONE_K : size_t = 1024;
let slice : &mut[u8] = unsafe {
let mem = mmap(std::ptr::null_mut(), 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, ONE_K, 10 * ONE_K,
MRemapFlags::MREMAP_MAYMOVE, 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(target_os = "linux")]
fn test_mremap_shrink() {
const ONE_K : size_t = 1024;
let slice : &mut[u8] = unsafe {
let mem = mmap(std::ptr::null_mut(), 10 * 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, 10 * ONE_K, 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);
}
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