ctool/memory/allocator/allocator.h
2025-04-08 01:15:51 +02:00

205 lines
7.2 KiB
C

/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* allocator.h :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: victor </var/spool/mail/victor> +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2025/04/05 17:04:18 by victor #+# #+# */
/* Updated: 2025/04/06 16:30:24 by victor ### ########.fr */
/* */
/* ************************************************************************** */
#ifndef ALLOCATOR_H
# define ALLOCATOR_H
# include "inc/arena.h"
typedef struct s_alloc {
void *mem;
size_t size;
} t_alloc;
typedef t_arena t_vector ;
typedef struct s_allocator {
void *mem;
t_vector allocs;
size_t cap;
t_vector free; // this will be used as Array of t_alloc
} t_allocator;
//global allocator that will be used by this lib
static t_allocator *allocator_get(void) {
static t_allocator a = { 0 };
return &a;
}
void allocator_init(size_t base_mem);
void *alloc(uint64_t size);
void *zalloc(uint32_t size);
void dealloc(void *ptr);
void allocator_shutdown(void);
#ifdef ALLOCATOR_IMPLEMENTATION
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include "allocator.h"
#include <stddef.h>
void allocator_init(size_t base_mem) {
t_allocator *allocator = allocator_get();
allocator->free = arena_create_growing(sizeof(t_alloc) * 1000);
allocator->mem = calloc(base_mem, sizeof((char)0));
allocator->allocs = arena_create_growing(sizeof(t_alloc) * 1000);
allocator->cap = base_mem;
}
void vector_push(t_vector *vec, void *mem, size_t memsize) {
assert(memsize < (vec->cap - vec->used));
void *ptr = arena_alloc(vec, memsize);
assert(ptr);
memmove(ptr, mem, memsize);
}
void vector_pop(t_vector *vec, size_t memsize) {
assert(memsize <= vec->used);
memset(&((uint8_t *)vec->mem)[vec->used - memsize], 0, memsize);
}
// offset is used to know where to dereference the memory to find the value to be sorted by
void vector_insert_sorted(t_vector *vec, void *mem, uint32_t memsize, uint32_t offset) {
uint32_t low_pos = 0;
uint32_t high_pos = vec->count - (vec->count > 0);
int32_t position = 0;
t_alloc *cursor = &((t_alloc *)vec->mem)[high_pos];
uint32_t new_alloc_size = *((uint8_t *)mem + offset);
if (new_alloc_size > cursor->size || vec->count == 0) {
vector_push(vec, mem, memsize);
} else {
while (low_pos < high_pos) {
position = low_pos + (high_pos - low_pos) / 2;
cursor = &((t_alloc *)vec->mem)[position];
assert((uint8_t *)cursor - (uint8_t *)vec->mem >= 0);
assert((uint8_t *)vec->mem + vec->used - (uint8_t *)cursor >= 0);
if (cursor->size < new_alloc_size) {
low_pos = position + 1;
} else if (cursor->size > new_alloc_size) {
high_pos = position - 1;
} else {
break ;
}
}
void *ptr = arena_alloc(vec, memsize);
memmove(ptr, &cursor, sizeof(*cursor) * (vec->count - low_pos));
memmove(&cursor, mem, memsize);
}
}
void vector_remove(t_vector *vec, uint32_t index, size_t memsize) {
assert(index <= vec->count);
void *item = (void *)&((uint8_t *)vec->mem)[index * memsize];
memmove(item, (uint8_t *)item + memsize, (vec->count - index) * memsize);
vec->count--;
vec->used -= memsize;
}
void *alloc(uint64_t size) {
void *ptr = NULL;
t_allocator *allocator = allocator_get();
if (size > 0) {
t_alloc *tail = &((t_alloc *)allocator->free.mem)[allocator->free.count - (allocator->free.count > 0)];
if (allocator->free.count > 0 && tail->size >= size) {
assert(tail->mem);
uint32_t position = allocator->free.count / 2;
t_alloc *candidate = NULL;
uint32_t range = size / 20;
uint32_t last_pos = position;
while (1) {
t_alloc *cursor = &((t_alloc *)allocator->free.mem)[position];
if (cursor->size > size + range) {
if (cursor->size < candidate->size) {
candidate = cursor;
}
position <<= 1;
} else if (cursor->size < size) {
position += position >> 1;
} else if ((cursor->size >= size && cursor->size <= size + range) || position == last_pos) {
ptr = cursor->mem;
t_alloc new = { ptr, size };
t_alloc old = { (uint8_t *)ptr + size, cursor->size - size };
vector_insert_sorted(&allocator->allocs, &new, sizeof(new), offsetof(t_alloc, size));
vector_insert_sorted(&allocator->allocs, &old, sizeof(old), offsetof(t_alloc, size));
vector_insert_sorted(&allocator->free, &old, sizeof(old), offsetof(t_alloc, size));
vector_remove(&allocator->free, position, sizeof(*cursor));
break ;
}
}
} else {
t_alloc *tail = &((t_alloc *)allocator->allocs.mem)[allocator->allocs.count - (allocator->allocs.count > 0)];
if (tail->mem == NULL) {
ptr = allocator->mem;
} else {
ptr = (uint8_t *)tail->mem + tail->size;
}
t_alloc new = (t_alloc){ ptr, size };
vector_push(&allocator->allocs, &new, sizeof(new));
}
}
return ptr;
}
void *zalloc(uint32_t size) {
uint8_t *ptr = NULL;
ptr = alloc(size);
for (uint i = 0; i < size; ++i) {
ptr[i] = 0;
}
return ptr;
}
void dealloc(void *ptr) {
t_allocator *allocator = allocator_get();
for (uint32_t i = 0; i < allocator->allocs.count; ++i) {
if (((t_alloc *)allocator->allocs.mem)[i].mem == ptr) {
t_alloc move = ((t_alloc *)allocator->allocs.mem)[i];
memset(move.mem, 'X', move.size);
vector_remove(&allocator->allocs, i, sizeof(move));
vector_insert_sorted(&allocator->free, &move, sizeof(move), offsetof(t_alloc, size));
break ;
}
}
}
void allocator_print(void) {
t_allocator *allocator = allocator_get();
printf( "---- Allocator ----\n"
"capacity: %lu\n", allocator->cap);
printf("currently used mem: \n");
arena_print(&allocator->allocs);
printf("currently freed mem: \n");
arena_print(&allocator->free);
printf("alloc mem start: %p\n", allocator->mem);
print_memory(allocator->mem, 0, allocator->cap);
}
void allocator_shutdown() {
t_allocator *allocator = allocator_get();
arena_destroy(&allocator->free);
arena_destroy(&allocator->allocs);
free(allocator->mem);
memset(allocator, 0, sizeof(*allocator));
}
#endif // ALLOCATOR_IMPLEMENTATION
#endif // !ALLOCATOR_H