arena.h File Reference

Arena allocator. More...

#include "align.h"
#include "is_pow2.h"
#include <assert.h>
#include <stdalign.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

Go to the source code of this file.

Classes
struct	arena
	Arena data struct. More...
struct	temp_arena_state
	Tempory arena state struct. More...

Functions
static void	arena_init (struct arena *self, const size_t len, unsigned char *backing_buf)
	Initialize the arena.
static void	arena_deallocate_all (struct arena *self)
	Deallocate all allocations in the arena.
static void *	arena_allocate_aligned (struct arena *self, const size_t alignment, const size_t size)
	Get the pointer to a chunk of the arena. With specific alignment.
static void *	arena_allocate (struct arena *self, const size_t size)
	Get the pointer to a chunk of the arena.
static void *	arena_reallocate_aligned (struct arena *self, void *old_ptr_, const size_t alignment, const size_t old_size, const size_t new_size)
	Reallocate a previously allocated chunk in the arena. With specific aligment.
static void *	arena_reallocate (struct arena *self, void *old_ptr, const size_t old_size, const size_t new_size)
	Reallocate a previously allocated chunk in the arena.
static struct temp_arena_state	temp_arena_state_save (struct arena *arena_ptr)
	Save the arena state temporarily.
static void	temp_arena_state_restore (struct temp_arena_state prev_state)
	Restore the arena state.

Detailed Description

Arena allocator.

For a comprehensive source, read:

• https://www.gingerbill.org/article/2019/02/08/memory-allocation-strategies-002/

Function Documentation

arena_allocate()

static void * arena_allocate ( struct arena * self, const size_t size )

inlinestatic

Get the pointer to a chunk of the arena.

Parameters

[in]	self	The arena pointer.
[in]	size	The section size in bytes.

Returns

A pointer to a zeroed-out memory chunk.

Return values

NULL	If the arena doesn't have enough memory for the allocation.

arena_allocate_aligned()

static void * arena_allocate_aligned ( struct arena * self, const size_t alignment, const size_t size )

inlinestatic

Get the pointer to a chunk of the arena. With specific alignment.

Parameters

[in]	self	arena pointer.
[in]	alignment	alignment size
[in]	size	chunk size

Returns

A pointer to a zeroed-out memory chunk.

Return values

NULL	If the arena doesn't have enough memory for the allocation.

arena_deallocate_all()

static void arena_deallocate_all ( struct arena * self )

inlinestatic

Deallocate all allocations in the arena.

Parameters

[in]

self

Arena pointer.

arena_init()

static void arena_init ( struct arena * self, const size_t len, unsigned char * backing_buf )

inlinestatic

Initialize the arena.

Parameters

[in]	self	Arena pointer.
[in]	len	Backing buffer length.
[in]	backing_buf	Backing buffer.

arena_reallocate()

static void * arena_reallocate ( struct arena * self, void * old_ptr, const size_t old_size, const size_t new_size )

inlinestatic

Reallocate a previously allocated chunk in the arena.

Parameters

[in]	self	The arena pointer.
[in]	old_ptr	Pointer to the buffer to reallocate
[in]	old_size	Old size.
[in]	new_size	New size to grow/shrink to.

Returns

A pointer to the reallocated memory chunk.

Return values

NULL	If arena doesn't have enough memory for the reallocation or invalid parameters are given.

arena_reallocate_aligned()

static void * arena_reallocate_aligned ( struct arena * self, void * old_ptr_, const size_t alignment, const size_t old_size, const size_t new_size )

inlinestatic

Reallocate a previously allocated chunk in the arena. With specific aligment.

Parameters

[in]	self	Arena pointer.
[in]	old_ptr_	Pointer to the buffer to reallocate
[in]	alignment	Alignment size.
[in]	old_size	Old size.
[in]	new_size	New size to grow/shrink to.

Returns

A pointer to the reallocated memory chunk.

Return values

NULL	If arena doesn't have enough memory for the reallocation or invalid parameters are given.

temp_arena_state_restore()

static void temp_arena_state_restore ( struct temp_arena_state prev_state )

inlinestatic

Restore the arena state.

Parameters

[in]

prev_state

Stored arena state.

temp_arena_state_save()

static struct temp_arena_state temp_arena_state_save ( struct arena * arena_ptr )

inlinestatic

Save the arena state temporarily.

Parameters

[in]

arena_ptr

The arena whose state to save.