rust/src/libstd/rt/global_heap.rs
2013-07-15 23:57:27 -04:00

124 lines
3.4 KiB
Rust

// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use libc::{c_void, c_char, size_t, uintptr_t, free, malloc, realloc};
use managed::raw::{BoxHeaderRepr, BoxRepr};
use unstable::intrinsics::TyDesc;
use sys::size_of;
extern {
#[rust_stack]
fn abort();
}
#[inline]
fn get_box_size(body_size: uint, body_align: uint) -> uint {
let header_size = size_of::<BoxHeaderRepr>();
// FIXME (#2699): This alignment calculation is suspicious. Is it right?
let total_size = align_to(header_size, body_align) + body_size;
total_size
}
// Rounds |size| to the nearest |alignment|. Invariant: |alignment| is a power
// of two.
#[inline]
fn align_to(size: uint, align: uint) -> uint {
assert!(align != 0);
(size + align - 1) & !(align - 1)
}
/// A wrapper around libc::malloc, aborting on out-of-memory
#[inline]
pub unsafe fn malloc_raw(size: uint) -> *c_void {
let p = malloc(size as size_t);
if p.is_null() {
// we need a non-allocating way to print an error here
abort();
}
p
}
/// A wrapper around libc::realloc, aborting on out-of-memory
#[inline]
pub unsafe fn realloc_raw(ptr: *mut c_void, size: uint) -> *mut c_void {
let p = realloc(ptr, size as size_t);
if p.is_null() {
// we need a non-allocating way to print an error here
abort();
}
p
}
// FIXME #4942: Make these signatures agree with exchange_alloc's signatures
#[cfg(stage0, not(test))]
#[lang="exchange_malloc"]
#[inline]
pub unsafe fn exchange_malloc(td: *c_char, size: uintptr_t) -> *c_char {
let td = td as *TyDesc;
let size = size as uint;
assert!(td.is_not_null());
let total_size = get_box_size(size, (*td).align);
let p = malloc_raw(total_size as uint);
let box: *mut BoxRepr = p as *mut BoxRepr;
(*box).header.ref_count = -1;
(*box).header.type_desc = td;
box as *c_char
}
/// The allocator for unique pointers without contained managed pointers.
#[cfg(not(stage0), not(test))]
#[lang="exchange_malloc"]
#[inline]
pub unsafe fn exchange_malloc(size: uintptr_t) -> *c_char {
malloc_raw(size as uint) as *c_char
}
// FIXME: #7496
#[cfg(not(test))]
#[lang="closure_exchange_malloc"]
#[inline]
pub unsafe fn closure_exchange_malloc_(td: *c_char, size: uintptr_t) -> *c_char {
closure_exchange_malloc(td, size)
}
#[inline]
pub unsafe fn closure_exchange_malloc(td: *c_char, size: uintptr_t) -> *c_char {
let td = td as *TyDesc;
let size = size as uint;
assert!(td.is_not_null());
let total_size = get_box_size(size, (*td).align);
let p = malloc_raw(total_size as uint);
let box: *mut BoxRepr = p as *mut BoxRepr;
(*box).header.type_desc = td;
box as *c_char
}
// NB: Calls to free CANNOT be allowed to fail, as throwing an exception from
// inside a landing pad may corrupt the state of the exception handler.
#[cfg(not(test))]
#[lang="exchange_free"]
#[inline]
pub unsafe fn exchange_free_(ptr: *c_char) {
exchange_free(ptr)
}
#[inline]
pub unsafe fn exchange_free(ptr: *c_char) {
free(ptr as *c_void);
}