diff options
Diffstat (limited to 'src/libcore/alloc.rs')
| -rw-r--r-- | src/libcore/alloc.rs | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/src/libcore/alloc.rs b/src/libcore/alloc.rs index 113a85abecb..58639808fae 100644 --- a/src/libcore/alloc.rs +++ b/src/libcore/alloc.rs @@ -218,6 +218,23 @@ impl Layout { len_rounded_up.wrapping_sub(len) } + /// Creates a layout by rounding the size of this layout up to a multiple + /// of the layout's alignment. + /// + /// Returns `Err` if the padded size would overflow. + /// + /// This is equivalent to adding the result of `padding_needed_for` + /// to the layout's current size. + #[unstable(feature = "alloc_layout_extra", issue = "55724")] + #[inline] + pub fn pad_to_align(&self) -> Result<Layout, LayoutErr> { + let pad = self.padding_needed_for(self.align()); + let new_size = self.size().checked_add(pad) + .ok_or(LayoutErr { private: () })?; + + Layout::from_size_align(new_size, self.align()) + } + /// Creates a layout describing the record for `n` instances of /// `self`, with a suitable amount of padding between each to /// ensure that each instance is given its requested size and @@ -506,7 +523,7 @@ pub unsafe trait GlobalAlloc { ptr } - /// Shink or grow a block of memory to the given `new_size`. + /// Shrink or grow a block of memory to the given `new_size`. /// The block is described by the given `ptr` pointer and `layout`. /// /// If this returns a non-null pointer, then ownership of the memory block @@ -757,7 +774,7 @@ pub unsafe trait Alloc { // realloc. alloc_excess, realloc_excess /// Returns a pointer suitable for holding data described by - /// a new layout with `layout`’s alginment and a size given + /// a new layout with `layout`’s alignment and a size given /// by `new_size`. To /// accomplish this, this may extend or shrink the allocation /// referenced by `ptr` to fit the new layout. |