1
0
Fork 0
mirror of https://gitlab.com/sortix/sortix.git synced 2023-02-13 20:55:38 -05:00
sortix--sortix/libc/stdlib/free.cpp
2016-01-26 22:48:40 +01:00

85 lines
2.4 KiB
C++

/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014, 2015.
This file is part of the Sortix C Library.
The Sortix C Library is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
The Sortix C Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
stdlib/free.cpp
Returns a chunk of memory to the dynamic memory heap.
*******************************************************************************/
#include <malloc.h>
#include <stdlib.h>
#if defined(HEAP_NO_ASSERT)
#define __heap_verify() ((void) 0)
#undef assert
#define assert(x) do { ((void) 0); } while ( 0 )
#endif
#if !defined(HEAP_GUARD_DEBUG)
extern "C" void free(void* addr)
{
if ( !addr )
return;
__heap_lock();
__heap_verify();
// Retrieve the chunk that contains this allocation.
struct heap_chunk* chunk = heap_data_to_chunk((uint8_t*) addr);
// Return the chunk to the heap.
heap_insert_chunk(chunk);
// Combine the chunk with its left and right neighbors if they are unused.
heap_chunk_combine_neighbors(chunk);
__heap_verify();
__heap_unlock();
}
#else
#if defined(__is_sortix_kernel)
#include <sortix/kernel/addralloc.h>
#include <sortix/kernel/memorymanagement.h>
#else
#include <sys/mman.h>
#endif
extern "C" void free(void* addr)
{
if ( !addr )
return;
#if defined(__is_sortix_kernel)
using namespace Sortix;
addralloc_t* alloc_ptr = (addralloc_t*) Page::AlignDown((uintptr_t) addr - 16);
assert(alloc_ptr->from == (uintptr_t) alloc_ptr);
addralloc_t alloc = *alloc_ptr;
Memory::UnmapRange(alloc.from, alloc.size - Page::Size(), PAGE_USAGE_KERNEL_HEAP);
FreeKernelAddress(&alloc);
#else
struct heap_alloc* alloc_ptr =
(struct heap_alloc*) HEAP_ALIGN_PAGEDOWN((uintptr_t) addr - 16);
munmap((void*) alloc_ptr->from, alloc_ptr->size);
#endif
}
#endif