Use new allocator API, and otherwise update for new Rust

- New allocator API
- Remove the "allocator" feature, which should be unnecessary due to how
the new allocator API works
- NonZero no longer implements Deref (rust-lang/rust#41064)
- NonZero::new() returns an Option; use NonZero::new_unchecked()
- Thread locals are no longer 'static (rust-lang/rust#43746)
- Changes to feature flags
- Use unsafe to access extern static (rust-lang/rust#36247)

Author: ids1024

Cargo.toml

@@ -29,10 +29,9 @@ debug-assertions = false
 codegen-units = 1
 
 [features]
-default = ["allocator", "tls"]
+default = ["tls"]
 # ---
 alloc_id = []
-allocator = []
 debugger = []
 log = ["write", "alloc_id"]
 no_log_lock = ["log"]

shim/src/thread_destructor.rs

@@ -22,10 +22,10 @@ pub mod arch {
         /// A thread destructor.
         type Dtor = unsafe extern fn(dtor: unsafe extern fn(*mut u8), arg: *mut u8, dso_handle: *mut u8) -> i32;
 
-        // Make sure the symbols exist.
-        assert!(!__cxa_thread_atexit_impl.is_null());
-
         unsafe {
+            // Make sure the symbols exist.
+            assert!(!__cxa_thread_atexit_impl.is_null());
+
             mem::transmute::<*const u8, Dtor>(__cxa_thread_atexit_impl)
                 (dtor, t, &__dso_handle as *const _ as *mut _)
         };

src/allocator.rs

@@ -300,7 +300,7 @@ impl Allocator for LocalAllocator {
 pub fn alloc(size: usize, align: usize) -> *mut u8 {
     log!(CALL, "Allocating buffer of size {} (align {}).", size, align);
 
-    get_allocator!(|alloc| *Pointer::from(alloc.alloc(size, align)))
+    get_allocator!(|alloc| Pointer::from(alloc.alloc(size, align)).get())
 }
 
 /// Free a buffer.
@@ -353,11 +353,11 @@ pub unsafe fn realloc(ptr: *mut u8, old_size: usize, size: usize, align: usize)
     log!(CALL, "Reallocating buffer of size {} to new size {}.", old_size, size);
 
     get_allocator!(|alloc| {
-        *Pointer::from(alloc.realloc(
+        Pointer::from(alloc.realloc(
             Block::from_raw_parts(Pointer::new(ptr), old_size),
             size,
             align
-        ))
+        )).get()
     })
 }
 

src/block.rs

@@ -110,7 +110,7 @@ impl Block {
     /// Is this block aligned to `align`?
     #[inline]
     pub fn aligned_to(&self, align: usize) -> bool {
-        *self.ptr as usize % align == 0
+        self.ptr.get() as usize % align == 0
     }
 
     /// memcpy the block to another pointer.
@@ -129,7 +129,7 @@ impl Block {
             // LAST AUDIT: 2016-08-21 (Ticki).
 
             // From the invariants of `Block`, this copy is well-defined.
-            ptr::copy_nonoverlapping(*self.ptr, *block.ptr, self.size);
+            ptr::copy_nonoverlapping(self.ptr.get(), block.ptr.get(), self.size);
         }
     }
 
@@ -145,7 +145,7 @@ impl Block {
 
                 // Since the memory of the block is inaccessible (read-wise), zeroing it is fully
                 // safe.
-                intrinsics::volatile_set_memory(*self.ptr, 0, self.size);
+                intrinsics::volatile_set_memory(self.ptr.get(), 0, self.size);
             }
         }
     }
@@ -162,7 +162,7 @@ impl Block {
     #[inline]
     pub fn left_to(&self, to: &Block) -> bool {
         // This won't overflow due to the end being bounded by the address space.
-        self.size + *self.ptr as usize == *to.ptr as usize
+        self.size + self.ptr.get() as usize == to.ptr.get() as usize
     }
 
     /// Split the block at some position.
@@ -207,7 +207,7 @@ impl Block {
 
         // Calculate the aligner, which defines the smallest size required as precursor to align
         // the block to `align`.
-        let aligner = (align - *self.ptr as usize % align) % align;
+        let aligner = (align - self.ptr.get() as usize % align) % align;
         //                                                 ^^^^^^^^
         // To avoid wasting space on the case where the block is already aligned, we calculate it
         // modulo `align`.
@@ -275,30 +275,30 @@ impl From<Block> for Pointer<u8> {
 impl PartialOrd for Block {
     #[inline]
     fn partial_cmp(&self, other: &Block) -> Option<cmp::Ordering> {
-        self.ptr.partial_cmp(&other.ptr)
+        self.ptr.get().partial_cmp(&other.ptr.get())
     }
 }
 
 /// Compare the blocks address.
 impl Ord for Block {
     #[inline]
     fn cmp(&self, other: &Block) -> cmp::Ordering {
-        self.ptr.cmp(&other.ptr)
+        self.ptr.get().cmp(&other.ptr.get())
     }
 }
 
 impl cmp::PartialEq for Block {
     #[inline]
     fn eq(&self, other: &Block) -> bool {
-        *self.ptr == *other.ptr
+        self.ptr.get() == other.ptr.get()
     }
 }
 
 impl cmp::Eq for Block {}
 
 impl fmt::Debug for Block {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "0x{:x}[{}]", *self.ptr as usize, self.size)
+        write!(f, "0x{:x}[{}]", self.ptr.get() as usize, self.size)
     }
 }
 

src/brk.rs

@@ -46,7 +46,7 @@ impl BrkLock {
         let expected_brk = self.current_brk().offset(size);
 
         // Break it to me, babe!
-        let old_brk = Pointer::new(syscalls::brk(*expected_brk as *const u8) as *mut u8);
+        let old_brk = Pointer::new(syscalls::brk(expected_brk.get() as *const u8) as *mut u8);
 
         /// AAAARGH WAY TOO MUCH LOGGING
         ///
@@ -180,7 +180,7 @@ pub fn lock() -> BrkLock {
 ///
 /// On failure the maximum pointer (`!0 as *mut u8`) is returned.
 pub unsafe extern fn sbrk(size: isize) -> *mut u8 {
-    *lock().sbrk(size).unwrap_or_else(|()| Pointer::new(!0 as *mut u8))
+    lock().sbrk(size).unwrap_or_else(|()| Pointer::new(!0 as *mut u8)).get()
 }
 
 /// Get the current program break.

src/lib.rs

@@ -9,29 +9,28 @@
 //! relatively strong condition, which means that you are forced to rewrite primitives and make
 //! sure no allocation ever happens.
 
-#![cfg_attr(feature = "allocator", allocator)]
 #![cfg_attr(feature = "clippy", feature(plugin))]
 #![cfg_attr(feature = "clippy", plugin(clippy))]
 
 #![no_std]
 
-#![feature(allocator, const_fn, core_intrinsics, stmt_expr_attributes, drop_types_in_const,
+#![feature(alloc, allocator_api, const_fn, core_intrinsics, stmt_expr_attributes, drop_types_in_const,
            nonzero, optin_builtin_traits, type_ascription, thread_local, linkage,
-           try_from)]
+           try_from, const_unsafe_cell_new, const_atomic_bool_new, const_nonzero_new,
+           const_atomic_ptr_new)]
 #![warn(missing_docs, cast_precision_loss, cast_sign_loss, cast_possible_wrap,
         cast_possible_truncation, filter_map, if_not_else, items_after_statements,
         invalid_upcast_comparisons, mutex_integer, nonminimal_bool, shadow_same, shadow_unrelated,
         single_match_else, string_add, string_add_assign, wrong_pub_self_convention)]
 
+extern crate alloc;
 extern crate ralloc_shim as shim;
 
 #[macro_use]
 mod log;
 #[macro_use]
 #[cfg(feature = "tls")]
 mod tls;
-#[cfg(feature = "allocator")]
-mod symbols;
 
 #[macro_use]
 mod unborrow;
@@ -49,8 +48,47 @@ mod ptr;
 mod sync;
 mod vec;
 
+use alloc::heap::{Alloc, AllocErr, Layout, CannotReallocInPlace};
+
 pub use allocator::{alloc, free, realloc, realloc_inplace};
 pub use brk::sbrk;
 pub use fail::set_oom_handler;
 #[cfg(feature = "tls")]
 pub use fail::set_thread_oom_handler;
+
+pub struct Allocator;
+
+unsafe impl<'a> Alloc for &'a Allocator {
+    unsafe fn alloc(&mut self, layout: Layout) -> Result<*mut u8, AllocErr> {
+        Ok(allocator::alloc(layout.size(), layout.align()))
+    }
+
+    unsafe fn dealloc(&mut self, ptr: *mut u8, layout: Layout) {
+        allocator::free(ptr, layout.size());
+    }
+
+    unsafe fn realloc(&mut self, ptr: *mut u8, layout: Layout, new_layout: Layout) -> Result<*mut u8, AllocErr> {
+        Ok(allocator::realloc(ptr, layout.size(), new_layout.size(), new_layout.align()))
+    }
+
+    unsafe fn grow_in_place(&mut self, ptr: *mut u8, layout: Layout, new_layout: Layout) -> Result<(), CannotReallocInPlace> {
+        if allocator::realloc_inplace(ptr, layout.size(), new_layout.size()).is_ok() {
+            Ok(())
+        } else {
+            Err(CannotReallocInPlace)
+        }
+    }
+
+    unsafe fn shrink_in_place(&mut self, ptr: *mut u8, layout: Layout, new_layout: Layout) -> Result<(), CannotReallocInPlace> {
+        if allocator::realloc_inplace(ptr, layout.size(), new_layout.size()).is_ok() {
+            Ok(())
+        } else {
+            Err(CannotReallocInPlace)
+        }
+    }
+
+    fn usable_size(&self, layout: &Layout) -> (usize, usize) {
+        // Yay! It matches exactly.
+        (layout.size(), layout.size())
+    }
+}

src/ptr.rs

@@ -30,7 +30,7 @@ impl<T> Pointer<T> {
         debug_assert!(!ptr.is_null(), "Null pointer!");
 
         Pointer {
-            ptr: NonZero::new(ptr),
+            ptr: NonZero::new_unchecked(ptr),
             _phantom: marker::PhantomData,
         }
     }
@@ -45,7 +45,7 @@ impl<T> Pointer<T> {
                 // LAST AUDIT: 2016-08-21 (Ticki).
 
                 // 0x1 is non-zero.
-                NonZero::new(0x1 as *mut T)
+                NonZero::new_unchecked(0x1 as *mut T)
             },
             _phantom: marker::PhantomData,
         }
@@ -61,7 +61,7 @@ impl<T> Pointer<T> {
                 // LAST AUDIT: 2016-08-21 (Ticki).
 
                 // Casting the pointer will preserve its nullable state.
-                NonZero::new(*self as *mut U)
+                NonZero::new_unchecked(self.get() as *mut U)
             },
             _phantom: marker::PhantomData,
         }
@@ -76,7 +76,11 @@ impl<T> Pointer<T> {
     /// This is unsafe, due to OOB offsets being undefined behavior.
     #[inline]
     pub unsafe fn offset(self, diff: isize) -> Pointer<T> {
-        Pointer::new(self.ptr.offset(diff))
+        Pointer::new(self.ptr.get().offset(diff))
+    }
+
+    pub fn get(&self) -> *mut T {
+        self.ptr.get()
     }
 }
 
@@ -89,15 +93,6 @@ impl<T> Default for Pointer<T> {
 unsafe impl<T: Send> Send for Pointer<T> {}
 unsafe impl<T: Sync> Sync for Pointer<T> {}
 
-impl<T> ops::Deref for Pointer<T> {
-    type Target = *mut T;
-
-    #[inline]
-    fn deref(&self) -> &*mut T {
-        &self.ptr
-    }
-}
-
 #[cfg(test)]
 mod test {
     use super::*;

src/symbols.rs

@@ -29,7 +29,7 @@ impl<T: 'static> Key<T> {
     /// Having a reference newtype would be unsound, due to the ability to leak a reference to
     /// another thread.
     #[inline]
-    pub fn with<F, R>(&'static self, f: F) -> R
+    pub fn with<F, R>(&self, f: F) -> R
         where F: FnOnce(&T) -> R {
         // Logging.
         log!(INTERNAL, "Accessing TLS variable.");
@@ -42,7 +42,7 @@ impl<T: 'static> Key<T> {
     /// Note that this has to be registered for every thread, it is needed for.
     // TODO: Make this automatic on `Drop`.
     #[inline]
-    pub fn register_thread_destructor(&'static self, dtor: extern fn(&T)) {
+    pub fn register_thread_destructor(&self, dtor: extern fn(&T)) {
         // Logging.
         log!(INTERNAL, "Registering thread destructor.");
 

src/tls.rs

@@ -68,7 +68,7 @@ impl<T: Leak> Vec<T> {
 
             // Due to the invariants of `Block`, this copy is safe (the pointer is valid and
             // unaliased).
-            ptr::copy_nonoverlapping(*old.ptr, *self.ptr, old.len);
+            ptr::copy_nonoverlapping(old.ptr.get(), self.ptr.get(), old.len);
         }
 
         Block::from(old)
@@ -95,7 +95,7 @@ impl<T: Leak> Vec<T> {
 
                 // By the invariants of this type (the size is bounded by the address space), this
                 // conversion isn't overflowing.
-                ptr::write((*self.ptr).offset(self.len as isize), elem);
+                ptr::write((self.ptr.get()).offset(self.len as isize), elem);
             }
 
             // Increment the length.
@@ -193,7 +193,7 @@ impl<T: Leak> ops::Deref for Vec<T> {
             // LAST AUDIT: 2016-08-21 (Ticki).
 
             // The invariants maintains safety.
-            slice::from_raw_parts(*self.ptr as *const T, self.len)
+            slice::from_raw_parts(self.ptr.get() as *const T, self.len)
         }
     }
 }
@@ -205,7 +205,7 @@ impl<T: Leak> ops::DerefMut for Vec<T> {
             // LAST AUDIT: 2016-08-21 (Ticki).
 
             // The invariants maintains safety.
-            slice::from_raw_parts_mut(*self.ptr as *mut T, self.len)
+            slice::from_raw_parts_mut(self.ptr.get() as *mut T, self.len)
         }
     }
 }