#pragma once

#include <c10/core/Allocator.h>
#include <c10/util/Exception.h>

// This file creates a fake allocator that just throws exceptions if
// it is actually used.

// state passed to the allocator is the std::function<void(void*)> called
// when the blob is release by ATen

namespace at {

static void* cpu_fixed_malloc(void*, ptrdiff_t) {
  TORCH_CHECK(false, "attempting to resize a tensor view of an external blob");
}

static void* cpu_fixed_realloc(void*, void*, ptrdiff_t) {
  TORCH_CHECK(false, "attempting to resize a tensor view of an external blob");
}

static void cpu_fixed_free(void* state, void* allocation) {
  auto on_release = static_cast<std::function<void(void*)>*>(state);
  (*on_release)(allocation);
  delete on_release;
}

static Allocator CPU_fixed_allocator = {
    cpu_fixed_malloc,
    cpu_fixed_realloc,
    cpu_fixed_free};

} // namespace at