/*
 * %CopyrightBegin%
 * 
 * Copyright Ericsson AB 1997-2022. All Rights Reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 * %CopyrightEnd%
 */
/*
 * This file handles differences between operating systems.
 * This should be the only place with conditional compilation
 * depending on the type of OS.
 */

#ifndef _ERL_WIN_SYS_H
#define _ERL_WIN_SYS_H

#define HAS_STDARG

#ifdef __GNUC__
#ifdef pid_t
/* Really... */
#undef pid_t
#endif
#endif
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <limits.h>
#include <process.h>
#include <malloc.h>
#ifndef __GNUC__
#include <direct.h>
#endif
#include "erl_errno.h"
#include <io.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <sys/timeb.h>

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#undef WIN32_LEAN_AND_MEAN


#ifndef MAXPATHLEN
#define MAXPATHLEN 4096
/*
   erts-6.0 (OTP 17.0):
   We now accept windows paths longer than 260 (MAX_PATH) by conversion to
   UNC path format. In order to also return long paths from the driver we
   increased MAXPATHLEN from 260 to larger (but arbitrary) value 4096.
   It would of course be nicer to instead dynamically allocate large enough
   tmp buffers when efile_drv needs to return really long paths, and do that
   for unix as well.
 */
#endif /* MAXPATHLEN */

/*
 * Various configuration options, used to be in the Makefile.
 */

#define NO_ASINH
#define NO_ACOSH
#define NO_ATANH
#define NO_ERF
#define NO_ERFC

#define NO_SYSCONF
#define NO_DAEMON
#define NO_PWD

#define strncasecmp _strnicmp

#ifndef __GNUC__
#  undef ERTS_I64_LITERAL
#  define ERTS_I64_LITERAL(X) X##i64
#endif

#define ERTS_HAVE_ERTS_SYS_ALIGNED_ALLOC 1

/*
 * Practical Windows specific macros.
 */

#define CreateAutoEvent(state) CreateEvent(NULL, FALSE, state, NULL)
#define CreateManualEvent(state) CreateEvent(NULL, TRUE, state, NULL)

/*
 * Min number of async threads
 */
#define ERTS_MIN_NO_OF_ASYNC_THREADS 0

/*
 * Our own type of "FD's"
 */
#define ERTS_SYS_FD_INVALID INVALID_HANDLE_VALUE
#define ERTS_SYS_FD_TYPE HANDLE
#define NO_FSTAT_ON_SYS_FD_TYPE 1 /* They are events, not files */

/*
 * For erl_time_sup
 */

#define SYS_CLK_TCK 1000
#define SYS_CLOCK_RESOLUTION 1

#if SIZEOF_TIME_T != 8
#  error "Unexpected sizeof(time_t)"
#endif

/*
 * gcc uses a 4 byte time_t and vc++ uses an 8 byte time_t.
 * Types seen in beam_emu.c *need* to have the same size
 * as in the rest of the system...
 */
typedef __int64 erts_time_t;

struct tm *sys_localtime_r(time_t *epochs, struct tm *ptm);
struct tm *sys_gmtime_r(time_t *epochs, struct tm *ptm);
time_t sys_mktime( struct tm *ptm);

#define gmtime_r sys_gmtime_r
#define HAVE_GMTIME_R
#define mktime sys_mktime

typedef struct {
    erts_time_t tv_sec;
    erts_time_t tv_usec;
} SysTimeval;

typedef struct {
    clock_t tms_utime;
    clock_t tms_stime;
    clock_t tms_cutime;
    clock_t tms_cstime;
} SysTimes;

#define HAVE_INT64 1
#if defined (__GNUC__)
typedef unsigned long long Uint64;
typedef long long          Sint64;
#  ifdef ULLONG_MAX
#    define ERTS_UINT64_MAX ULLONG_MAX
#  endif
#  ifdef LLONG_MAX
#    define ERTS_SINT64_MAX LLONG_MAX
#  endif
#  ifdef LLONG_MIN
#    define ERTS_SINT64_MIN LLONG_MIN
#  endif

typedef long long ErtsMonotonicTime;
typedef long long ErtsSysHrTime;
#else
typedef ULONGLONG Uint64;
typedef LONGLONG  Sint64;

typedef LONGLONG ErtsMonotonicTime;
typedef LONGLONG ErtsSysHrTime;
#endif

#define ErtsStrToSint64 _strtoi64

typedef ErtsMonotonicTime ErtsSystemTime;
typedef ErtsMonotonicTime ErtsSysPerfCounter;

ErtsSystemTime erts_os_system_time(void);

#define ERTS_MONOTONIC_TIME_MIN ((ErtsMonotonicTime) (1ULL << 63))
#define ERTS_MONOTONIC_TIME_MAX (~ERTS_MONOTONIC_TIME_MIN)

#define ERTS_HAVE_OS_MONOTONIC_TIME_SUPPORT 1
#define ERTS_COMPILE_TIME_MONOTONIC_TIME_UNIT 0

struct erts_sys_time_read_only_data__ {
    ErtsMonotonicTime (*os_monotonic_time)(void);
    void (*os_times)(ErtsMonotonicTime *, ErtsSystemTime*);
    ErtsSysHrTime (*sys_hrtime)(void);
};

typedef struct {
    union {
	struct erts_sys_time_read_only_data__ o;
	char align__[(((sizeof(struct erts_sys_time_read_only_data__) - 1)
		       / ASSUMED_CACHE_LINE_SIZE) + 1)
		     * ASSUMED_CACHE_LINE_SIZE];
    } r;
} ErtsSysTimeData__;

extern ErtsSysTimeData__ erts_sys_time_data__;

ERTS_GLB_INLINE ErtsMonotonicTime erts_os_monotonic_time(void);
ERTS_GLB_INLINE void erts_os_times(ErtsMonotonicTime *,
				   ErtsSystemTime *);
ERTS_GLB_INLINE ErtsSysHrTime erts_sys_hrtime(void);
ERTS_GLB_INLINE ErtsSysPerfCounter erts_sys_perf_counter(void);

#if ERTS_GLB_INLINE_INCL_FUNC_DEF

ERTS_GLB_INLINE ErtsMonotonicTime
erts_os_monotonic_time(void)
{
    return (*erts_sys_time_data__.r.o.os_monotonic_time)();
}

ERTS_GLB_INLINE void
erts_os_times(ErtsMonotonicTime *mtimep, ErtsSystemTime *stimep)
{
    (*erts_sys_time_data__.r.o.os_times)(mtimep, stimep);
}

ERTS_GLB_INLINE ErtsSysHrTime
erts_sys_hrtime(void)
{
    return (*erts_sys_time_data__.r.o.sys_hrtime)();
}

ERTS_GLB_INLINE ErtsSysPerfCounter
erts_sys_perf_counter(void)
{
    return (*erts_sys_time_data__.r.o.sys_hrtime)();
}

ERTS_GLB_INLINE ErtsSysPerfCounter
erts_sys_perf_counter_unit(void)
{
    return 1000 * 1000 * 1000;
}

#endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */

extern void sys_gettimeofday(SysTimeval *tv);
extern clock_t sys_times(SysTimes *buffer);

extern char *win_build_environment(char *);

typedef struct {
    WCHAR *environment_strings;
    WCHAR *next_string;
} GETENV_STATE;

void erts_sys_env_init(void);

/*
 ** These are to avoid irritating warnings
 */
#pragma warning(disable : 4244)
#pragma warning(disable : 4018)

/*
 * Floating point support.
 */

extern volatile int erl_fp_exception;

#include <float.h>
/* I suspect this test isn't right, it might depend on the version of GCC
   rather than if it's a MINGW gcc, but I haven't been able to pinpoint the
   exact point where _finite was added to the headers in cygwin... */
#if defined (__GNUC__) && !defined(__MINGW32__)
int _finite(double x);
#endif

#define erts_isfinite _finite

/*#define NO_FPE_SIGNALS*/
#define erts_get_current_fp_exception() NULL
#define __ERTS_FP_CHECK_INIT(fpexnp) do {} while (0)
#define __ERTS_FP_ERROR(fpexnp, f, Action) if (!_finite(f)) { Action; } else {}
#define __ERTS_FP_ERROR_THOROUGH(fpexnp, f, Action) __ERTS_FP_ERROR(fpexnp, f, Action)
#define __ERTS_SAVE_FP_EXCEPTION(fpexnp)
#define __ERTS_RESTORE_FP_EXCEPTION(fpexnp)

#define ERTS_FP_CHECK_INIT(p)		__ERTS_FP_CHECK_INIT(&(p)->fp_exception)
#define ERTS_FP_ERROR(p, f, A)		__ERTS_FP_ERROR(&(p)->fp_exception, f, A)
#define ERTS_SAVE_FP_EXCEPTION(p)	__ERTS_SAVE_FP_EXCEPTION(&(p)->fp_exception)
#define ERTS_RESTORE_FP_EXCEPTION(p)	__ERTS_RESTORE_FP_EXCEPTION(&(p)->fp_exception)
#define ERTS_FP_ERROR_THOROUGH(p, f, A)	__ERTS_FP_ERROR_THOROUGH(&(p)->fp_exception, f, A)

#define erts_sys_block_fpe() 0
#define erts_sys_unblock_fpe(x) do{}while(0)

/*
 * Seems to be missing.
 */
#ifndef __GNUC__
typedef long ssize_t;
#endif

/* Threads */
int init_async(int);
int exit_async(void);

#define ERTS_HAVE_TRY_CATCH 1

#define ERTS_SYS_TRY_CATCH(EXPR,CATCH)                                  \
    __try {                                                             \
    EXPR;                                                               \
    }                                                                   \
    __except(GetExceptionCode() == EXCEPTION_ACCESS_VIOLATION ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH) \
    {                                                                   \
        CATCH;                                                          \
    }

#endif
