growl/next/core/arena.c

26 lines
777 B
C

#include <growl.h>
#include <stdlib.h>
#include <string.h>
void growl_arena_init(GrowlGCArena *arena, size_t size) {
arena->start = arena->free = malloc(size);
if (arena->start == NULL)
abort();
arena->end = arena->start + size;
}
void growl_arena_free(GrowlGCArena *arena) {
free(arena->start);
arena->start = arena->end = arena->free = NULL;
}
void *growl_arena_alloc(GrowlGCArena *arena, size_t size, size_t align,
size_t count) {
ptrdiff_t padding = -(uintptr_t)arena->start & (align - 1);
ptrdiff_t available = arena->end - arena->start - padding;
if (available < 0 || count > available / size)
abort();
void *p = arena->start + padding;
arena->start += padding + count * size;
return memset(p, 0, count * size);
}