Assert the LSB is 0 when converting Vec into Bytes

This commit is contained in:
Sean McArthur
2019-12-12 11:46:51 -08:00
parent 17a8ac91e0
commit 8733f74d59
2 changed files with 47 additions and 5 deletions
+29 -3
View File
@@ -257,8 +257,20 @@ impl Bytes {
let sub_p = subset.as_ptr() as usize;
let sub_len = subset.len();
assert!(sub_p >= bytes_p);
assert!(sub_p + sub_len <= bytes_p + bytes_len);
assert!(
sub_p >= bytes_p,
"subset pointer ({:p}) is smaller than self pointer ({:p})",
sub_p as *const u8,
bytes_p as *const u8,
);
assert!(
sub_p + sub_len <= bytes_p + bytes_len,
"subset is out of bounds: self = ({:p}, {}), subset = ({:p}, {})",
bytes_p as *const u8,
bytes_len,
sub_p as *const u8,
sub_len,
);
let sub_offset = sub_p - bytes_p;
@@ -719,6 +731,12 @@ impl From<Vec<u8>> for Bytes {
let slice = vec.into_boxed_slice();
let len = slice.len();
let ptr = slice.as_ptr();
assert!(
ptr as usize & KIND_VEC == 0,
"Vec pointer should not have LSB set: {:p}",
ptr,
);
drop(Box::into_raw(slice));
let data = ptr as usize | KIND_VEC;
@@ -808,7 +826,15 @@ unsafe fn shared_drop(data: &mut AtomicPtr<()>, ptr: *const u8, len: usize) {
}
unsafe fn rebuild_vec(shared: *const (), offset: *const u8, len: usize) -> Vec<u8> {
debug_assert_eq!(shared as usize & KIND_MASK, KIND_VEC);
debug_assert!(
shared as usize & KIND_MASK == KIND_VEC,
"rebuild_vec should have beeen called with KIND_VEC",
);
debug_assert!(
shared as usize & !KIND_MASK != 0,
"rebuild_vec should be called with non-null pointer: {:p}",
shared,
);
let buf = (shared as usize & !KIND_MASK) as *mut u8;
let cap = (offset as usize - buf as usize) + len;