/*************************************************************************/
/*  typedefs.h                                                           */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
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/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
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/*************************************************************************/

#ifndef TYPEDEFS_H
#define TYPEDEFS_H

#include <stddef.h>

/**
 * Basic definitions and simple functions to be used everywhere.
 */

#include "platform_config.h"

#ifndef _STR
#define _STR(m_x) #m_x
#define _MKSTR(m_x) _STR(m_x)
#endif

//should always inline no matter what
#ifndef _ALWAYS_INLINE_

#if defined(__GNUC__) && (__GNUC__ >= 4)
#define _ALWAYS_INLINE_ __attribute__((always_inline)) inline
#elif defined(__llvm__)
#define _ALWAYS_INLINE_ __attribute__((always_inline)) inline
#elif defined(_MSC_VER)
#define _ALWAYS_INLINE_ __forceinline
#else
#define _ALWAYS_INLINE_ inline
#endif

#endif

//should always inline, except in some cases because it makes debugging harder
#ifndef _FORCE_INLINE_

#ifdef DISABLE_FORCED_INLINE
#define _FORCE_INLINE_ inline
#else
#define _FORCE_INLINE_ _ALWAYS_INLINE_
#endif

#endif

//custom, gcc-safe offsetof, because gcc complains a lot.
template <class T>
T *_nullptr() {
	T *t = NULL;
	return t;
}

#define OFFSET_OF(st, m) \
	((size_t)((char *)&(_nullptr<st>()->m) - (char *)0))
/**
 * Some platforms (devices) don't define NULL
 */

#ifndef NULL
#define NULL 0
#endif

/**
 * Windows badly defines a lot of stuff we'll never use. Undefine it.
 */

#ifdef _WIN32
#undef min // override standard definition
#undef max // override standard definition
#undef ERROR // override (really stupid) wingdi.h standard definition
#undef DELETE // override (another really stupid) winnt.h standard definition
#undef MessageBox // override winuser.h standard definition
#undef MIN // override standard definition
#undef MAX // override standard definition
#undef CLAMP // override standard definition
#undef Error
#undef OK
#undef CONNECT_DEFERRED // override from Windows SDK, clashes with Object enum
#endif

#include "core/int_types.h"

#include "core/error_list.h"

/** Generic ABS function, for math uses please use Math::abs */

#ifndef ABS
#define ABS(m_v) (((m_v) < 0) ? (-(m_v)) : (m_v))
#endif

#define ABSDIFF(x, y) (((x) < (y)) ? ((y) - (x)) : ((x) - (y)))

#ifndef SGN
#define SGN(m_v) (((m_v) < 0) ? (-1.0) : (+1.0))
#endif

#ifndef MIN
#define MIN(m_a, m_b) (((m_a) < (m_b)) ? (m_a) : (m_b))
#endif

#ifndef MAX
#define MAX(m_a, m_b) (((m_a) > (m_b)) ? (m_a) : (m_b))
#endif

#ifndef CLAMP
#define CLAMP(m_a, m_min, m_max) (((m_a) < (m_min)) ? (m_min) : (((m_a) > (m_max)) ? m_max : m_a))
#endif

/** Generic swap template */
#ifndef SWAP

#define SWAP(m_x, m_y) __swap_tmpl((m_x), (m_y))
template <class T>
inline void __swap_tmpl(T &x, T &y) {

	T aux = x;
	x = y;
	y = aux;
}

#endif //swap

/* clang-format off */
#define HEX2CHR(m_hex) \
	((m_hex >= '0' && m_hex <= '9') ? (m_hex - '0') : \
	((m_hex >= 'A' && m_hex <= 'F') ? (10 + m_hex - 'A') : \
	((m_hex >= 'a' && m_hex <= 'f') ? (10 + m_hex - 'a') : 0)))
/* clang-format on */

// Macro to check whether we are compiled by clang
// and we have a specific builtin
#if defined(__llvm__) && defined(__has_builtin)
#define _llvm_has_builtin(x) __has_builtin(x)
#else
#define _llvm_has_builtin(x) 0
#endif

#if (defined(__GNUC__) && (__GNUC__ >= 5)) || _llvm_has_builtin(__builtin_mul_overflow)
#define _mul_overflow __builtin_mul_overflow
#endif

#if (defined(__GNUC__) && (__GNUC__ >= 5)) || _llvm_has_builtin(__builtin_add_overflow)
#define _add_overflow __builtin_add_overflow
#endif

/** Function to find the next power of 2 to an integer */

static _FORCE_INLINE_ unsigned int next_power_of_2(unsigned int x) {

	if (x == 0)
		return 0;

	--x;
	x |= x >> 1;
	x |= x >> 2;
	x |= x >> 4;
	x |= x >> 8;
	x |= x >> 16;

	return ++x;
}

static _FORCE_INLINE_ unsigned int previous_power_of_2(unsigned int x) {

	x |= x >> 1;
	x |= x >> 2;
	x |= x >> 4;
	x |= x >> 8;
	x |= x >> 16;
	return x - (x >> 1);
}

static _FORCE_INLINE_ unsigned int closest_power_of_2(unsigned int x) {

	unsigned int nx = next_power_of_2(x);
	unsigned int px = previous_power_of_2(x);
	return (nx - x) > (x - px) ? px : nx;
}

// We need this definition inside the function below.
static inline int get_shift_from_power_of_2(unsigned int p_pixel);

template <class T>
static _FORCE_INLINE_ T nearest_power_of_2_templated(T x) {

	--x;

	// The number of operations on x is the base two logarithm
	// of the p_number of bits in the type. Add three to account
	// for sizeof(T) being in bytes.
	size_t num = get_shift_from_power_of_2(sizeof(T)) + 3;

	// If the compiler is smart, it unrolls this loop
	// If its dumb, this is a bit slow.
	for (size_t i = 0; i < num; i++)
		x |= x >> (1 << i);

	return ++x;
}

/** Function to find the nearest (bigger) power of 2 to an integer */

static inline unsigned int nearest_shift(unsigned int p_number) {

	for (int i = 30; i >= 0; i--) {

		if (p_number & (1 << i))
			return i + 1;
	}

	return 0;
}

/** get a shift value from a power of 2 */
static inline int get_shift_from_power_of_2(unsigned int p_pixel) {
	// return a GL_TEXTURE_SIZE_ENUM

	for (unsigned int i = 0; i < 32; i++) {

		if (p_pixel == (unsigned int)(1 << i))
			return i;
	}

	return -1;
}

/** Swap 16 bits value for endianness */
#if defined(__GNUC__) || _llvm_has_builtin(__builtin_bswap16)
#define BSWAP16(x) __builtin_bswap16(x)
#else
static inline uint16_t BSWAP16(uint16_t x) {
	return (x >> 8) | (x << 8);
}
#endif

/** Swap 32 bits value for endianness */
#if defined(__GNUC__) || _llvm_has_builtin(__builtin_bswap32)
#define BSWAP32(x) __builtin_bswap32(x)
#else
static inline uint32_t BSWAP32(uint32_t x) {
	return ((x << 24) | ((x << 8) & 0x00FF0000) | ((x >> 8) & 0x0000FF00) | (x >> 24));
}
#endif

/** Swap 64 bits value for endianness */
#if defined(__GNUC__) || _llvm_has_builtin(__builtin_bswap64)
#define BSWAP64(x) __builtin_bswap64(x)
#else
static inline uint64_t BSWAP64(uint64_t x) {
	x = (x & 0x00000000FFFFFFFF) << 32 | (x & 0xFFFFFFFF00000000) >> 32;
	x = (x & 0x0000FFFF0000FFFF) << 16 | (x & 0xFFFF0000FFFF0000) >> 16;
	x = (x & 0x00FF00FF00FF00FF) << 8 | (x & 0xFF00FF00FF00FF00) >> 8;
	return x;
}
#endif

/** When compiling with RTTI, we can add an "extra"
 * layer of safeness in many operations, so dynamic_cast
 * is used besides casting by enum.
 */

template <class T>
struct Comparator {

	_ALWAYS_INLINE_ bool operator()(const T &p_a, const T &p_b) const { return (p_a < p_b); }
};

void _global_lock();
void _global_unlock();

struct _GlobalLock {

	_GlobalLock() { _global_lock(); }
	~_GlobalLock() { _global_unlock(); }
};

#define GLOBAL_LOCK_FUNCTION _GlobalLock _global_lock_;

#ifdef NO_SAFE_CAST
#define SAFE_CAST static_cast
#else
#define SAFE_CAST dynamic_cast
#endif

#define MT_SAFE

#define __STRX(m_index) #m_index
#define __STR(m_index) __STRX(m_index)

#ifdef __GNUC__
#define likely(x) __builtin_expect(!!(x), 1)
#define unlikely(x) __builtin_expect(!!(x), 0)
#else
#define likely(x) x
#define unlikely(x) x
#endif

#if defined(__GNUC__)
#define _PRINTF_FORMAT_ATTRIBUTE_2_0 __attribute__((format(printf, 2, 0)))
#define _PRINTF_FORMAT_ATTRIBUTE_2_3 __attribute__((format(printf, 2, 3)))
#else
#define _PRINTF_FORMAT_ATTRIBUTE_2_0
#define _PRINTF_FORMAT_ATTRIBUTE_2_3
#endif

/** This is needed due to a strange OpenGL API that expects a pointer
 *  type for an argument that is actually an offset.
 */
#define CAST_INT_TO_UCHAR_PTR(ptr) ((uint8_t *)(uintptr_t)(ptr))

/** Hint for compilers that this fallthrough in a switch is intentional.
 *  Can be replaced by [[fallthrough]] annotation if we move to C++17.
 *  Including conditional support for it for people who set -std=c++17
 *  themselves.
 *  Requires a trailing semicolon when used.
 */
#if __cplusplus >= 201703L
#define FALLTHROUGH [[fallthrough]]
#elif defined(__GNUC__) && __GNUC__ >= 7
#define FALLTHROUGH __attribute__((fallthrough))
#elif defined(__llvm__) && __cplusplus >= 201103L && defined(__has_feature)
#if __has_feature(cxx_attributes) && defined(__has_warning)
#if __has_warning("-Wimplicit-fallthrough")
#define FALLTHROUGH [[clang::fallthrough]]
#endif
#endif
#endif

#ifndef FALLTHROUGH
#define FALLTHROUGH
#endif

#endif // TYPEDEFS_H
