mem.h

/*
 * Copyright 2006-2022 René Ferdinand Rivera Morell
 * Distributed under the Boost Software License, Version 1.0.
 * (See accompanying file LICENSE.txt or copy at
 * https://www.bfgroup.xyz/b2/LICENSE.txt)
 */

#ifndef BJAM_MEM_H
#define BJAM_MEM_H

#include "config.h"

#include <cstdlib>
#include <memory>

#define bjam_malloc_x(s) std::malloc(s)
#define bjam_calloc_x(n, s) std::calloc(n, s)
#define bjam_realloc_x(p, s) std::realloc(p, s)
#define bjam_free_x(p) std::free(p)

#ifndef bjam_malloc_atomic_x
#define bjam_malloc_atomic_x(s) bjam_malloc_x(s)
#endif
#ifndef bjam_calloc_atomic_x
#define bjam_calloc_atomic_x(n, s) bjam_calloc_x(n, s)
#endif
#ifndef bjam_mem_init_x
#define bjam_mem_init_x()
#endif
#ifndef bjam_mem_close_x
#define bjam_mem_close_x()
#endif
#ifndef bjam_malloc_raw_x
#define bjam_malloc_raw_x(s) bjam_malloc_x(s)
#endif
#ifndef bjam_calloc_raw_x
#define bjam_calloc_raw_x(n, s) bjam_calloc_x(n, s)
#endif
#ifndef bjam_realloc_raw_x
#define bjam_realloc_raw_x(p, s) bjam_realloc_x(p, s)
#endif
#ifndef bjam_free_raw_x
#define bjam_free_raw_x(p) bjam_free_x(p)
#endif

#ifdef OPT_DEBUG_PROFILE
/* Profile tracing of memory allocations. */
#include "debug.h"

#define BJAM_MALLOC(s) (profile_memory(s), bjam_malloc_x(s))
#define BJAM_MALLOC_ATOMIC(s) (profile_memory(s), bjam_malloc_atomic_x(s))
#define BJAM_CALLOC(n, s) (profile_memory(n * s), bjam_calloc_x(n, s))
#define BJAM_CALLOC_ATOMIC(n, s) \
(profile_memory(n * s), bjam_calloc_atomic_x(n, s))
#define BJAM_REALLOC(p, s) (profile_memory(s), bjam_realloc_x(p, s))

#define BJAM_MALLOC_RAW(s) (profile_memory(s), bjam_malloc_raw_x(s))
#define BJAM_CALLOC_RAW(n, s) (profile_memory(n * s), bjam_calloc_raw_x(n, s))
#define BJAM_REALLOC_RAW(p, s) (profile_memory(s), bjam_realloc_raw_x(p, s))
#else
/* No mem tracing. */
#define BJAM_MALLOC(s) bjam_malloc_x(s)
#define BJAM_MALLOC_ATOMIC(s) bjam_malloc_atomic_x(s)
#define BJAM_CALLOC(n, s) bjam_calloc_x(n, s)
#define BJAM_CALLOC_ATOMIC(n, s) bjam_calloc_atomic_x(n, s)
#define BJAM_REALLOC(p, s) bjam_realloc_x(p, s)

#define BJAM_MALLOC_RAW(s) bjam_malloc_raw_x(s)
#define BJAM_CALLOC_RAW(n, s) bjam_calloc_raw_x(n, s)
#define BJAM_REALLOC_RAW(p, s) bjam_realloc_raw_x(p, s)
#endif

#define BJAM_MEM_INIT() bjam_mem_init_x()
#define BJAM_MEM_CLOSE() bjam_mem_close_x()

#define BJAM_FREE(p) bjam_free_x(p)
#define BJAM_FREE_RAW(p) bjam_free_raw_x(p)

namespace b2 { namespace jam {

// Zero-init and call constructor at the given pre-allocated memory.
template <typename T, typename... Args>
T * ctor_ptr(void * p, Args &&... args)
{
	std::memset(p, 0, sizeof(T));
	return new (p) T(std::forward<Args>(args)...);
}

// Call destructor at the given memory.
template <typename T>
void dtor_ptr(T * p)
{
	p->~T();
}

// Allocate memory and construct a type with args.
template <typename T, typename... Args>
T * make_ptr(Args &&... args)
{
	return ctor_ptr<T>(BJAM_MALLOC(sizeof(T)), std::forward<Args>(args)...);
}

// Allocate memory, with tail padding, and construct a type with args.
template <typename T, typename... Args>
T * make_ptr_extra(std::size_t padding, Args &&... args)
{
	return ctor_ptr<T>(
		BJAM_MALLOC(sizeof(T) + padding), std::forward<Args>(args)...);
}

// Destructs and deallocates an object.
template <typename T>
void free_ptr(T * p)
{
	dtor_ptr(p);
	BJAM_FREE(p);
}

// Unique ptr deleter that destructs and frees the memory.
template <typename T>
struct unique_jptr_deleter
{
	void operator()(T * p) const
	{
		p->~T();
		BJAM_FREE(p);
	}
};

// Unique ptr that will delete and free using the jam memory functions.
template <typename T>
using unique_jptr = std::unique_ptr<T, unique_jptr_deleter<T>>;

// Allocate and construct an object with args using the jam memory functions.
template <typename T, typename... Args>
unique_jptr<T> make_unique_jptr(Args &&... args)
{
	return unique_jptr<T>(make_ptr<T>(std::forward<Args>(args)...));
}

// Allocate, with tail padding, and construct an object with args using the jam
// memory functions.
template <typename T, typename... Args>
unique_jptr<T> make_unique_jptr_extra(std::size_t padding, Args &&... args)
{
	return unique_jptr<T>(
		make_ptr_extra<T>(padding, std::forward<Args>(args)...));
}

template <typename T>
struct unique_jptr_free
{
	using free_f = void (*)(T *);

	explicit unique_jptr_free(free_f f)
		: free_function(f)
	{}

	unique_jptr_free(unique_jptr_free && p)
		: free_function(std::move(p.free_function))
	{
		p.free_function = nullptr;
	}

	void operator()(T * p) const
	{
		// if (free_function)
		if (p) (*free_function)(p);
	}

	private:
	free_f free_function = nullptr;
};

template <typename T>
using unique_bare_jptr = std::unique_ptr<T, unique_jptr_free<T>>;

template <typename T, typename F>
unique_bare_jptr<T> make_unique_bare_jptr(T * p, F exit_f)
{
	return unique_bare_jptr<T>(p, unique_jptr_free<T>(exit_f));
}

template <typename T, typename F, typename G>
unique_bare_jptr<T> make_unique_bare_jptr(T * p, F enter_f, G exit_f)
{
	enter_f(p);
	return unique_bare_jptr<T>(p, unique_jptr_free<T>(exit_f));
}

}} // namespace b2::jam

#endif