4coder/4ed_system_allocator.cpp

62 lines
1.6 KiB
C++

/*
* 4coder malloc base allocator
*/
// TOP
internal void*
base_reserve__system(void *user_data, umem size, umem *size_out){
System_Functions *system = (System_Functions*)user_data;
umem extra_size = 128;
umem increased_size = size + extra_size;
size = round_up_umem(increased_size, KB(4));
*size_out = size - extra_size;
void *ptr = system->memory_allocate(size);
*(umem*)ptr = size;
ptr = (u8*)ptr + extra_size;
return(ptr);
}
internal void
base_free__system(void *user_data, void *ptr){
System_Functions *system = (System_Functions*)user_data;
umem extra_size = 128;
ptr = (u8*)ptr - extra_size;
umem size = *(umem*)ptr;
system->memory_free(ptr, size);
}
internal Base_Allocator
make_base_allocator_system(System_Functions *system){
return(make_base_allocator(base_reserve__system, 0, 0,
base_free__system, 0, system));
}
global Base_Allocator base_allocator_system = {};
internal Base_Allocator*
get_base_allocator_system(System_Functions *system){
if (base_allocator_system.reserve == 0){
base_allocator_system = make_base_allocator_system(system);
}
return(&base_allocator_system);
}
internal Arena
make_arena_system(System_Functions *system, umem chunk_size, umem align){
return(make_arena(get_base_allocator_system(system), chunk_size, align));
}
internal Arena
make_arena_system(System_Functions *system, umem chunk_size){
return(make_arena_system(system, chunk_size, 8));
}
internal Arena
make_arena_system(System_Functions *system){
return(make_arena_system(system, KB(16), 8));
}
// BOTTOM