40 lines
1.2 KiB
C
40 lines
1.2 KiB
C
#include "arena_allocator.h"
|
|
|
|
#include "assert.h"
|
|
#include "vector.h"
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
static ArenaBlock arena_block_alloc(size_t size) {
|
|
size = size < ARENA_BLOCK_SIZE ? ARENA_BLOCK_SIZE : size;
|
|
byte *ptr = malloc(size);
|
|
assert_alloc(ptr);
|
|
return (ArenaBlock){.data = ptr, .size = size, .end = ptr + size};
|
|
}
|
|
|
|
void arena_block_drop(ArenaBlock block) { free(block.data); }
|
|
|
|
ArenaAllocator arena_init() {
|
|
ArenaBlock block = arena_block_alloc(ARENA_BLOCK_SIZE);
|
|
ArenaBlockVec blocks = vec_init();
|
|
vec_grow(&blocks, 256);
|
|
vec_push(&blocks, block);
|
|
ArenaBlock *last = blocks.data;
|
|
return (ArenaAllocator){.blocks = blocks, .ptr = last->data, .last = last};
|
|
}
|
|
void *arena_alloc(ArenaAllocator *alloc, size_t size) {
|
|
if (alloc->ptr + size > alloc->last->end) {
|
|
ArenaBlock block = arena_block_alloc(size);
|
|
vec_push(&alloc->blocks, block);
|
|
ArenaBlock *last = &alloc->blocks.data[alloc->blocks.len - 1];
|
|
alloc->ptr = last->data;
|
|
alloc->last = last;
|
|
}
|
|
|
|
byte *ptr = alloc->ptr;
|
|
alloc->ptr += size;
|
|
return ptr;
|
|
}
|
|
void arena_drop(ArenaAllocator arena) { vec_drop(arena.blocks); }
|