// Copyright (C) 2004-2021 Artifex Software, Inc.
//
// This file is part of MuPDF.
//
// MuPDF is free software: you can redistribute it and/or modify it under the
// terms of the GNU Affero General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// MuPDF is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
// details.
//
// You should have received a copy of the GNU Affero General Public License
// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>
//
// Alternative licensing terms are available from the licensor.
// For commercial licensing, see <https://www.artifex.com/> or contact
// Artifex Software, Inc., 1305 Grant Avenue - Suite 200, Novato,
// CA 94945, U.S.A., +1(415)492-9861, for further information.

#ifndef MUPDF_FITZ_SYSTEM_H
#define MUPDF_FITZ_SYSTEM_H

/* Turn on valgrind pacification in debug builds. */
#ifndef NDEBUG
#ifndef PACIFY_VALGRIND
#define PACIFY_VALGRIND
#endif
#endif

/**
	Include the standard libc headers.
*/

#include <stddef.h> /* needed for size_t */
#include <stdarg.h> /* needed for va_list vararg functions */
#include <setjmp.h> /* needed for the try/catch macros */
#include <stdio.h> /* useful for debug printfs */

#include "export.h"

#if defined(_MSC_VER) && (_MSC_VER < 1700) /* MSVC older than VS2012 */
typedef signed char int8_t;
typedef short int int16_t;
typedef int int32_t;
typedef __int64 int64_t;
typedef unsigned char uint8_t;
typedef unsigned short int uint16_t;
typedef unsigned int uint32_t;
typedef unsigned __int64 uint64_t;
#ifndef INT64_MAX
#define INT64_MAX 9223372036854775807i64
#endif
#else
#include <stdint.h> /* needed for int64_t */
#endif

#include "mupdf/memento.h"
#include "mupdf/fitz/track-usage.h"

#define nelem(x) (sizeof(x)/sizeof((x)[0]))

#define FZ_PI 3.14159265f
#define FZ_RADIAN 57.2957795f
#define FZ_DEGREE 0.017453292f
#define FZ_SQRT2 1.41421356f
#define FZ_LN2 0.69314718f

/**
	Spot architectures where we have optimisations.
*/

#if defined(__arm__) || defined(__thumb__)
#ifndef ARCH_ARM
#define ARCH_ARM
#endif
#endif

/**
	Some differences in libc can be smoothed over
*/

#ifndef __STRICT_ANSI__
#if defined(__APPLE__)
#ifndef HAVE_SIGSETJMP
#define HAVE_SIGSETJMP 1
#endif
#elif defined(__unix)
#ifndef __EMSCRIPTEN__
#ifndef HAVE_SIGSETJMP
#define HAVE_SIGSETJMP 1
#endif
#endif
#endif
#endif
#ifndef HAVE_SIGSETJMP
#define HAVE_SIGSETJMP 0
#endif

/**
	Where possible (i.e. on platforms on which they are provided),
	use sigsetjmp/siglongjmp in preference to setjmp/longjmp. We
	don't alter signal handlers within mupdf, so there is no need
	for us to store/restore them - hence we use the non-restoring
	variants. This makes a large speed difference on MacOSX (and
	probably other platforms too.
*/
#if HAVE_SIGSETJMP
#define fz_setjmp(BUF) sigsetjmp(BUF, 0)
#define fz_longjmp(BUF,VAL) siglongjmp(BUF, VAL)
typedef sigjmp_buf fz_jmp_buf;
#else
#define fz_setjmp(BUF) setjmp(BUF)
#define fz_longjmp(BUF,VAL) longjmp(BUF,VAL)
typedef jmp_buf fz_jmp_buf;
#endif

/* these constants mirror the corresponding macros in stdio.h */
#ifndef EOF
#define EOF (-1)
#endif
#ifndef SEEK_SET
#define SEEK_SET 0
#endif
#ifndef SEEK_CUR
#define SEEK_CUR 1
#endif
#ifndef SEEK_END
#define SEEK_END 2
#endif

#ifdef _MSC_VER /* Microsoft Visual C */

/* MSVC up to VS2012 */
#if _MSC_VER < 1800
static __inline int signbit(double x)
{
	union
	{
		double d;
		__int64 i;
	} u;
	u.d = x;
	return (int)(u.i>>63);
}
#endif

#pragma warning( disable: 4244 ) /* conversion from X to Y, possible loss of data */
#pragma warning( disable: 4701 ) /* Potentially uninitialized local variable 'name' used */
#pragma warning( disable: 4996 ) /* 'function': was declared deprecated */

#if _MSC_VER <= 1700 /* MSVC 2012 */
#define isnan(x) _isnan(x)
#define isinf(x) (!_finite(x))
#endif

#if _MSC_VER <= 1920 /* MSVC 2019 */
#define hypotf _hypotf
#endif
#define atoll _atoi64

#endif

#ifdef _WIN32

char *fz_utf8_from_wchar(const wchar_t *s);
wchar_t *fz_wchar_from_utf8(const char *s);

/* really a FILE* but we don't want to include stdio.h here */
void *fz_fopen_utf8(const char *name, const char *mode);
int fz_remove_utf8(const char *name);

char **fz_argv_from_wargv(int argc, wchar_t **wargv);
void fz_free_argv(int argc, char **argv);

#endif

/* Cope with systems (such as Windows) with no S_ISDIR */
#ifndef S_ISDIR
#define S_ISDIR(mode) ((mode) & S_IFDIR)
#endif

/* inline is standard in C++. For some compilers we can enable it within
 * C too. */

#ifndef __cplusplus
#if defined (__STDC_VERSION_) && (__STDC_VERSION__ >= 199901L) /* C99 */
#elif defined(_MSC_VER) && (_MSC_VER >= 1500) /* MSVC 9 or newer */
#define inline __inline
#elif defined(__GNUC__) && (__GNUC__ >= 3) /* GCC 3 or newer */
#define inline __inline
#else /* Unknown or ancient */
#define inline
#endif
#endif

/* restrict is standard in C99, but not in all C++ compilers. */
#if defined (__STDC_VERSION_) && (__STDC_VERSION__ >= 199901L) /* C99 */
#define FZ_RESTRICT restrict
#elif defined(_MSC_VER) && (_MSC_VER >= 1600) /* MSVC 10 or newer */
#define FZ_RESTRICT __restrict
#elif defined(__GNUC__) && (__GNUC__ >= 3) /* GCC 3 or newer */
#define FZ_RESTRICT __restrict
#else /* Unknown or ancient */
#define FZ_RESTRICT
#endif

/* noreturn is a GCC extension */
#ifdef __GNUC__
#define FZ_NORETURN __attribute__((noreturn))
#else
#ifdef _MSC_VER
#define FZ_NORETURN __declspec(noreturn)
#else
#define FZ_NORETURN
#endif
#endif

/* Flag unused parameters, for use with 'static inline' functions in
 * headers. */
#if defined(__GNUC__) && (__GNUC__ > 2 || __GNUC__ == 2 && __GNUC_MINOR__ >= 7)
#define FZ_UNUSED __attribute__((__unused__))
#else
#define FZ_UNUSED
#endif

/* GCC can do type checking of printf strings */
#ifdef __printflike
#define FZ_PRINTFLIKE(F,V) __printflike(F,V)
#else
#if defined(__GNUC__) && (__GNUC__ > 2 || __GNUC__ == 2 && __GNUC_MINOR__ >= 7)
#define FZ_PRINTFLIKE(F,V) __attribute__((__format__ (__printf__, F, V)))
#else
#define FZ_PRINTFLIKE(F,V)
#endif
#endif

/* ARM assembly specific defines */

#ifdef ARCH_ARM

/* If we're compiling as thumb code, then we need to tell the compiler
 * to enter and exit ARM mode around our assembly sections. If we move
 * the ARM functions to a separate file and arrange for it to be
 * compiled without thumb mode, we can save some time on entry.
 */
/* This is slightly suboptimal; __thumb__ and __thumb2__ become defined
 * and undefined by #pragma arm/#pragma thumb - but we can't define a
 * macro to track that. */
#if defined(__thumb__) || defined(__thumb2__)
#define ENTER_ARM ".balign 4\nmov r12,pc\nbx r12\n0:.arm\n"
#define ENTER_THUMB "9:.thumb\n"
#else
#define ENTER_ARM
#define ENTER_THUMB
#endif

#endif

/* Memory block alignment */

/* Most architectures are happy with blocks being aligned to the size
 * of void *'s. Some (notably sparc) are not.
 *
 * Some architectures (notably amd64) are happy for pointers to be 32bit
 * aligned even on 64bit systems. By making use of this we can save lots
 * of memory in data structures (notably the display list).
 *
 * We attempt to cope with these vagaries via the following definitions.
 */

/* All blocks allocated by mupdf's allocators are expected to be
 * returned aligned to FZ_MEMORY_BLOCK_ALIGN_MOD. This is sizeof(void *)
 * unless overwritten by a predefinition, or by a specific architecture
 * being detected. */
#ifndef FZ_MEMORY_BLOCK_ALIGN_MOD
#if defined(sparc) || defined(__sparc) || defined(__sparc__)
#define FZ_MEMORY_BLOCK_ALIGN_MOD 8
#else
#define FZ_MEMORY_BLOCK_ALIGN_MOD sizeof(void *)
#endif
#endif

/* MuPDF will ensure that its use of pointers in packed structures
 * (such as the display list) will be aligned to FZ_POINTER_ALIGN_MOD.
 * This is the same as FZ_MEMORY_BLOCK_ALIGN_MOD unless overridden by
 * a predefinition, or by a specific architecture being detected. */
#ifndef FZ_POINTER_ALIGN_MOD
#if defined(__amd64) || defined(__amd64__) || defined(__x86_64) || defined(__x86_64__)
#define FZ_POINTER_ALIGN_MOD 4
#else
#define FZ_POINTER_ALIGN_MOD FZ_MEMORY_BLOCK_ALIGN_MOD
#endif
#endif

#ifdef CLUSTER
/* Include this first so our defines don't clash with the system
 * definitions */
#include <math.h>
/**
 * Trig functions
 */
static float
my_atan_table[258] =
{
0.0000000000f, 0.00390623013f,0.00781234106f,0.0117182136f,
0.0156237286f, 0.0195287670f, 0.0234332099f, 0.0273369383f,
0.0312398334f, 0.0351417768f, 0.0390426500f, 0.0429423347f,
0.0468407129f, 0.0507376669f, 0.0546330792f, 0.0585268326f,
0.0624188100f, 0.0663088949f, 0.0701969711f, 0.0740829225f,
0.0779666338f, 0.0818479898f, 0.0857268758f, 0.0896031775f,
0.0934767812f, 0.0973475735f, 0.1012154420f, 0.1050802730f,
0.1089419570f, 0.1128003810f, 0.1166554350f, 0.1205070100f,
0.1243549950f, 0.1281992810f, 0.1320397620f, 0.1358763280f,
0.1397088740f, 0.1435372940f, 0.1473614810f, 0.1511813320f,
0.1549967420f, 0.1588076080f, 0.1626138290f, 0.1664153010f,
0.1702119250f, 0.1740036010f, 0.1777902290f, 0.1815717110f,
0.1853479500f, 0.1891188490f, 0.1928843120f, 0.1966442450f,
0.2003985540f, 0.2041471450f, 0.2078899270f, 0.2116268090f,
0.2153577000f, 0.2190825110f, 0.2228011540f, 0.2265135410f,
0.2302195870f, 0.2339192060f, 0.2376123140f, 0.2412988270f,
0.2449786630f, 0.2486517410f, 0.2523179810f, 0.2559773030f,
0.2596296290f, 0.2632748830f, 0.2669129880f, 0.2705438680f,
0.2741674510f, 0.2777836630f, 0.2813924330f, 0.2849936890f,
0.2885873620f, 0.2921733830f, 0.2957516860f, 0.2993222020f,
0.3028848680f, 0.3064396190f, 0.3099863910f, 0.3135251230f,
0.3170557530f, 0.3205782220f, 0.3240924700f, 0.3275984410f,
0.3310960770f, 0.3345853220f, 0.3380661230f, 0.3415384250f,
0.3450021770f, 0.3484573270f, 0.3519038250f, 0.3553416220f,
0.3587706700f, 0.3621909220f, 0.3656023320f, 0.3690048540f,
0.3723984470f, 0.3757830650f, 0.3791586690f, 0.3825252170f,
0.3858826690f, 0.3892309880f, 0.3925701350f, 0.3959000740f,
0.3992207700f, 0.4025321870f, 0.4058342930f, 0.4091270550f,
0.4124104420f, 0.4156844220f, 0.4189489670f, 0.4222040480f,
0.4254496370f, 0.4286857080f, 0.4319122350f, 0.4351291940f,
0.4383365600f, 0.4415343100f, 0.4447224240f, 0.4479008790f,
0.4510696560f, 0.4542287350f, 0.4573780990f, 0.4605177290f,
0.4636476090f, 0.4667677240f, 0.4698780580f, 0.4729785980f,
0.4760693300f, 0.4791502430f, 0.4822213240f, 0.4852825630f,
0.4883339510f, 0.4913754780f, 0.4944071350f, 0.4974289160f,
0.5004408130f, 0.5034428210f, 0.5064349340f, 0.5094171490f,
0.5123894600f, 0.5153518660f, 0.5183043630f, 0.5212469510f,
0.5241796290f, 0.5271023950f, 0.5300152510f, 0.5329181980f,
0.5358112380f, 0.5386943730f, 0.5415676050f, 0.5444309400f,
0.5472843810f, 0.5501279330f, 0.5529616020f, 0.5557853940f,
0.5585993150f, 0.5614033740f, 0.5641975770f, 0.5669819340f,
0.5697564530f, 0.5725211450f, 0.5752760180f, 0.5780210840f,
0.5807563530f, 0.5834818390f, 0.5861975510f, 0.5889035040f,
0.5915997100f, 0.5942861830f, 0.5969629370f, 0.5996299860f,
0.6022873460f, 0.6049350310f, 0.6075730580f, 0.6102014430f,
0.6128202020f, 0.6154293530f, 0.6180289120f, 0.6206188990f,
0.6231993300f, 0.6257702250f, 0.6283316020f, 0.6308834820f,
0.6334258830f, 0.6359588250f, 0.6384823300f, 0.6409964180f,
0.6435011090f, 0.6459964250f, 0.6484823880f, 0.6509590190f,
0.6534263410f, 0.6558843770f, 0.6583331480f, 0.6607726790f,
0.6632029930f, 0.6656241120f, 0.6680360620f, 0.6704388650f,
0.6728325470f, 0.6752171330f, 0.6775926450f, 0.6799591110f,
0.6823165550f, 0.6846650020f, 0.6870044780f, 0.6893350100f,
0.6916566220f, 0.6939693410f, 0.6962731940f, 0.6985682070f,
0.7008544080f, 0.7031318220f, 0.7054004770f, 0.7076604000f,
0.7099116190f, 0.7121541600f, 0.7143880520f, 0.7166133230f,
0.7188300000f, 0.7210381110f, 0.7232376840f, 0.7254287490f,
0.7276113330f, 0.7297854640f, 0.7319511710f, 0.7341084830f,
0.7362574290f, 0.7383980370f, 0.7405303370f, 0.7426543560f,
0.7447701260f, 0.7468776740f, 0.7489770290f, 0.7510682220f,
0.7531512810f, 0.7552262360f, 0.7572931160f, 0.7593519510f,
0.7614027700f, 0.7634456020f, 0.7654804790f, 0.7675074280f,
0.7695264800f, 0.7715376650f, 0.7735410110f, 0.7755365500f,
0.7775243100f, 0.7795043220f, 0.7814766150f, 0.7834412190f,
0.7853981630f, 0.7853981630f /* Extended by 1 for interpolation */
};

static inline float my_sinf(float x)
{
	float x2, xn;
	int i;
	/* Map x into the -PI to PI range. We could do this using:
	 * x = fmodf(x, 2.0f * FZ_PI);
	 * but that's C99, and seems to misbehave with negative numbers
	 * on some platforms. */
	x -= FZ_PI;
	i = x / (2.0f * FZ_PI);
	x -= i * 2.0f * FZ_PI;
	if (x < 0.0f)
		x += 2.0f * FZ_PI;
	x -= FZ_PI;
	if (x <= -FZ_PI / 2.0f)
		x = -FZ_PI - x;
	else if (x >= FZ_PI / 2.0f)
		x = FZ_PI-x;
	x2 = x * x;
	xn = x * x2 / 6.0f;
	x -= xn;
	xn *= x2 / 20.0f;
	x += xn;
	xn *= x2 / 42.0f;
	x -= xn;
	xn *= x2 / 72.0f;
	x += xn;
	return x;
}

static inline float my_atan2f(float o, float a)
{
	int negate = 0, flip = 0, i;
	float r, s;
	if (o == 0.0f)
	{
		if (a > 0)
			return 0.0f;
		else
			return FZ_PI;
	}
	if (o < 0)
		o = -o, negate = 1;
	if (a < 0)
		a = -a, flip = 1;
	if (o < a)
		i = 65536.0f * o / a + 0.5f;
	else
		i = 65536.0f * a / o + 0.5f;
	r = my_atan_table[i >> 8];
	s = my_atan_table[(i >> 8) + 1];
	r += (s - r) * (i & 255) / 256.0f;
	if (o >= a)
		r = FZ_PI / 2.0f - r;
	if (flip)
		r = FZ_PI - r;
	if (negate)
		r = -r;
	return r;
}

#define sinf(x) my_sinf(x)
#define cosf(x) my_sinf(FZ_PI / 2.0f + (x))
#define atan2f(x,y) my_atan2f((x),(y))
#endif

static inline int fz_is_pow2(int a)
{
	return (a != 0) && (a & (a-1)) == 0;
}

#endif
