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/*
* malloc.h
*
* Internals for the memory allocator
*/
#include <stdint.h>
#include <stddef.h>
#include "core.h"
/*
* This is a temporary hack. In Syslinux 5 this will be a pointer to
* the owner module.
*/
typedef size_t malloc_tag_t;
enum malloc_owner {
MALLOC_FREE,
MALLOC_HEAD,
MALLOC_CORE,
MALLOC_MODULE,
};
struct free_arena_header;
/*
* This structure should be a power of two. This becomes the
* alignment unit.
*/
struct arena_header {
malloc_tag_t tag;
size_t attrs; /* Bits 0..1: Type
2..3: Heap,
4..31: MSB of the size */
struct free_arena_header *next, *prev;
};
enum arena_type {
ARENA_TYPE_USED = 0,
ARENA_TYPE_FREE = 1,
ARENA_TYPE_HEAD = 2,
ARENA_TYPE_DEAD = 3,
};
enum heap {
HEAP_MAIN,
HEAP_LOWMEM,
NHEAP
};
#define ARENA_SIZE_MASK (~(uintptr_t)(sizeof(struct arena_header)-1))
#define ARENA_HEAP_MASK ((size_t)0xc)
#define ARENA_HEAP_POS 2
#define ARENA_TYPE_MASK ((size_t)0x3)
#define ARENA_ALIGN_UP(p) ((char *)(((uintptr_t)(p) + ~ARENA_SIZE_MASK) \
& ARENA_SIZE_MASK))
#define ARENA_ALIGN_DOWN(p) ((char *)((uintptr_t)(p) & ARENA_SIZE_MASK))
#define ARENA_SIZE_GET(attrs) ((attrs) & ARENA_SIZE_MASK)
#define ARENA_HEAP_GET(attrs) (((attrs) & ARENA_HEAP_MASK) >> ARENA_HEAP_POS)
#define ARENA_TYPE_GET(attrs) ((attrs) & ARENA_TYPE_MASK)
#define ARENA_SIZE_SET(attrs, size) \
((attrs) = ((size) & ARENA_SIZE_MASK) | ((attrs) & ~ARENA_SIZE_MASK))
#define ARENA_HEAP_SET(attrs, heap) \
((attrs) = (((heap) << ARENA_HEAP_POS) & ARENA_HEAP_MASK) | \
((attrs) & ~ARENA_HEAP_MASK))
#define ARENA_TYPE_SET(attrs, type) \
((attrs) = ((attrs) & ~ARENA_TYPE_MASK) | \
((type) & ARENA_TYPE_MASK))
/*
* This structure should be no more than twice the size of the
* previous structure.
*/
struct free_arena_header {
struct arena_header a;
struct free_arena_header *next_free, *prev_free;
size_t _pad[2]; /* Pad to 2*sizeof(struct arena_header) */
};
extern struct free_arena_header __malloc_head[NHEAP];
void __inject_free_block(struct free_arena_header *ah);
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