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//@ignore-target: windows # No mmap on Windows
//@compile-flags: -Zmiri-disable-isolation -Zmiri-permissive-provenance
use std::io::Error;
use std::{ptr, slice};
fn test_mmap<Offset: Default>(
mmap: unsafe extern "C" fn(
*mut libc::c_void,
libc::size_t,
libc::c_int,
libc::c_int,
libc::c_int,
Offset,
) -> *mut libc::c_void,
) {
let page_size = page_size::get();
let ptr = unsafe {
mmap(
ptr::null_mut(),
page_size,
libc::PROT_READ | libc::PROT_WRITE,
libc::MAP_PRIVATE | libc::MAP_ANONYMOUS,
-1,
Default::default(),
)
};
assert!(!ptr.is_null());
// Ensure that freshly mapped allocations are zeroed
let slice = unsafe { slice::from_raw_parts_mut(ptr as *mut u8, page_size) };
assert!(slice.iter().all(|b| *b == 0));
// Do some writes, make sure they worked
for b in slice.iter_mut() {
*b = 1;
}
assert!(slice.iter().all(|b| *b == 1));
// Ensure that we can munmap
let res = unsafe { libc::munmap(ptr, page_size) };
assert_eq!(res, 0i32);
// Test all of our error conditions
let ptr = unsafe {
mmap(
ptr::null_mut(),
page_size,
libc::PROT_READ | libc::PROT_WRITE,
libc::MAP_PRIVATE | libc::MAP_SHARED, // Can't be both private and shared
-1,
Default::default(),
)
};
assert_eq!(ptr, libc::MAP_FAILED);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
let ptr = unsafe {
mmap(
ptr::null_mut(),
0, // Can't map no memory
libc::PROT_READ | libc::PROT_WRITE,
libc::MAP_PRIVATE | libc::MAP_ANONYMOUS,
-1,
Default::default(),
)
};
assert_eq!(ptr, libc::MAP_FAILED);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
// We report an error for mappings whose length cannot be rounded up to a multiple of
// the page size.
let ptr = unsafe {
mmap(
ptr::null_mut(),
usize::MAX - 1,
libc::PROT_READ | libc::PROT_WRITE,
libc::MAP_PRIVATE | libc::MAP_ANONYMOUS,
-1,
Default::default(),
)
};
assert_eq!(ptr, libc::MAP_FAILED);
// We report an error when trying to munmap an address which is not a multiple of the page size
let res = unsafe { libc::munmap(ptr::without_provenance_mut(1), page_size) };
assert_eq!(res, -1);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
// We report an error when trying to munmap a length that cannot be rounded up to a multiple of
// the page size.
let res = unsafe { libc::munmap(ptr::without_provenance_mut(page_size), usize::MAX - 1) };
assert_eq!(res, -1);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
}
#[cfg(target_os = "linux")]
fn test_mremap() {
let page_size = page_size::get();
let ptr = unsafe {
libc::mmap(
ptr::null_mut(),
page_size,
libc::PROT_READ | libc::PROT_WRITE,
libc::MAP_PRIVATE | libc::MAP_ANONYMOUS,
-1,
0,
)
};
let slice = unsafe { slice::from_raw_parts_mut(ptr as *mut u8, page_size) };
for b in slice.iter_mut() {
*b = 1;
}
let ptr = unsafe { libc::mremap(ptr, page_size, page_size * 2, libc::MREMAP_MAYMOVE) };
assert!(!ptr.is_null());
let slice = unsafe { slice::from_raw_parts_mut(ptr as *mut u8, page_size * 2) };
assert!(&slice[..page_size].iter().all(|b| *b == 1));
assert!(&slice[page_size..].iter().all(|b| *b == 0));
let res = unsafe { libc::munmap(ptr, page_size * 2) };
assert_eq!(res, 0i32);
// Test all of our error conditions
// Not aligned
let ptr = unsafe {
libc::mremap(ptr::without_provenance_mut(1), page_size, page_size, libc::MREMAP_MAYMOVE)
};
assert_eq!(ptr, libc::MAP_FAILED);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
// Zero size
let ptr = unsafe { libc::mremap(ptr::null_mut(), page_size, 0, libc::MREMAP_MAYMOVE) };
assert_eq!(ptr, libc::MAP_FAILED);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
// Not setting MREMAP_MAYMOVE
let ptr = unsafe { libc::mremap(ptr::null_mut(), page_size, page_size, 0) };
assert_eq!(ptr, libc::MAP_FAILED);
assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);
}
fn main() {
test_mmap(libc::mmap);
#[cfg(target_os = "linux")]
test_mmap(libc::mmap64);
#[cfg(target_os = "linux")]
test_mremap();
}
|
