mirror of
https://github.com/RGBCube/serenity
synced 2025-07-26 07:07:45 +00:00
LibC: Move some of malloc's data structures into mallocdefs.h
This allows UE to see what the heap metadata looks like.
This commit is contained in:
parent
53cffb5ad9
commit
b494cfea38
2 changed files with 75 additions and 71 deletions
|
@ -26,5 +26,70 @@
|
|||
|
||||
#pragma once
|
||||
|
||||
#include <AK/InlineLinkedList.h>
|
||||
#include <AK/Types.h>
|
||||
|
||||
#define MAGIC_PAGE_HEADER 0x42657274 // 'Bert'
|
||||
#define MAGIC_BIGALLOC_HEADER 0x42697267 // 'Birg'
|
||||
#define MALLOC_SCRUB_BYTE 0xdc
|
||||
#define FREE_SCRUB_BYTE 0xed
|
||||
|
||||
static constexpr unsigned short size_classes[] = { 8, 16, 32, 64, 128, 256, 500, 1016, 2032, 4088, 8184, 16376, 32752, 0 };
|
||||
static constexpr size_t num_size_classes = (sizeof(size_classes) / sizeof(unsigned short)) - 1;
|
||||
|
||||
struct CommonHeader {
|
||||
size_t m_magic;
|
||||
size_t m_size;
|
||||
};
|
||||
|
||||
struct BigAllocationBlock : public CommonHeader {
|
||||
BigAllocationBlock(size_t size)
|
||||
{
|
||||
m_magic = MAGIC_BIGALLOC_HEADER;
|
||||
m_size = size;
|
||||
}
|
||||
unsigned char* m_slot[0];
|
||||
};
|
||||
|
||||
struct FreelistEntry {
|
||||
FreelistEntry* next;
|
||||
};
|
||||
|
||||
struct ChunkedBlock
|
||||
: public CommonHeader
|
||||
, public InlineLinkedListNode<ChunkedBlock> {
|
||||
|
||||
static constexpr size_t block_size = 64 * KiB;
|
||||
static constexpr size_t block_mask = ~(block_size - 1);
|
||||
|
||||
ChunkedBlock(size_t bytes_per_chunk)
|
||||
{
|
||||
m_magic = MAGIC_PAGE_HEADER;
|
||||
m_size = bytes_per_chunk;
|
||||
m_free_chunks = chunk_capacity();
|
||||
m_freelist = (FreelistEntry*)chunk(0);
|
||||
for (size_t i = 0; i < chunk_capacity(); ++i) {
|
||||
auto* entry = (FreelistEntry*)chunk(i);
|
||||
if (i != chunk_capacity() - 1)
|
||||
entry->next = (FreelistEntry*)chunk(i + 1);
|
||||
else
|
||||
entry->next = nullptr;
|
||||
}
|
||||
}
|
||||
|
||||
ChunkedBlock* m_prev { nullptr };
|
||||
ChunkedBlock* m_next { nullptr };
|
||||
FreelistEntry* m_freelist { nullptr };
|
||||
size_t m_free_chunks { 0 };
|
||||
[[gnu::aligned(8)]] unsigned char m_slot[0];
|
||||
|
||||
void* chunk(size_t index)
|
||||
{
|
||||
return &m_slot[index * m_size];
|
||||
}
|
||||
bool is_full() const { return m_free_chunks == 0; }
|
||||
size_t bytes_per_chunk() const { return m_size; }
|
||||
size_t free_chunks() const { return m_free_chunks; }
|
||||
size_t used_chunks() const { return chunk_capacity() - m_free_chunks; }
|
||||
size_t chunk_capacity() const { return (block_size - sizeof(ChunkedBlock)) / m_size; }
|
||||
};
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue