/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 * 
 *************************************************************/


#include <stdio.h>
#include <stdlib.h>

typedef enum { t_char, t_short, t_int, t_long, t_double } Type;
typedef int (*TestFunc)( Type, void* );

struct Description;

int IsBigEndian(void);
int IsStackGrowingDown_2( int * pI );
int IsStackGrowingDown(void);
int GetStackAlignment_3( char*p, long l, int i, short s, char b, char c, ... );
int GetStackAlignment_2( char*p, long l, int i, short s, char b, char c );
int GetStackAlignment(void);
void PrintArgs( int p, ... );
int check( TestFunc func, Type eT, void* p );

#if defined (UNX) || defined (WNT) || defined (OS2)

#ifdef UNX
#include <unistd.h>
#endif
#include <sys/types.h>

#define I_STDARG
#ifdef I_STDARG
#include <stdarg.h>
#else
#include <varargs.h>
#endif

#define NO_USE_FORK_TO_CHECK
#ifdef USE_FORK_TO_CHECK
#include <sys/wait.h>
#else
#include <signal.h>
#include <setjmp.h>
#endif

#else
#endif

#define printTypeSize(Type,Name)	printf(	"sizeof(%s)\t= %d\n", Name,	\
				sizeof (Type) )

#define isSignedType(Type)	(((Type)-1) < 0)
#define printTypeSign(Type,Name)	printf(	"%s\t= %s %s\n", Name,		\
				( isSignedType(Type) ? "unsigned" : "signed" ), Name )


int IsBigEndian()
{
  long l = 1;
  return ! *(char*)&l;
}

int IsStackGrowingDown_2( int * pI )
{
  int i = 1;
  return ((unsigned long)&i) < (unsigned long)pI;
}

int IsStackGrowingDown()
{
  int i = 1;
  return IsStackGrowingDown_2(&i);
}

int GetStackAlignment_3( char*p, long l, int i, short s, char b, char c, ... )
{
  (void) p; (void) l; (void) i; (void) s; /* unused */
  if ( IsStackGrowingDown() )
	return &c - &b;
  else
	return &b - &c;
}

int GetStackAlignment_2( char*p, long l, int i, short s, char b, char c )
{
  (void) p; (void) l; (void) i; (void) s; /* unused */
  if ( IsStackGrowingDown() )
	return &c - &b;
  else
	return &b - &c;
}

int GetStackAlignment()
{
  int nStackAlignment = GetStackAlignment_3(0,1,2,3,4,5);
  if ( nStackAlignment != GetStackAlignment_2(0,1,2,3,4,5) )
	printf( "Pascal calling convention\n" );
  return nStackAlignment;
}


#if defined (UNX) || defined (WNT) || defined (OS2)

#ifdef I_STDARG
void PrintArgs( int p, ... )
#else
void PrintArgs( p, va_alist )
int p;
va_dcl
#endif
{
	int value;
	va_list ap;

#ifdef I_STDARG
    va_start( ap, p );
#else
    va_start( ap );
#endif

	printf( "value = %d", p );

	while ( ( value = va_arg(ap, int) ) != 0 )
	  printf( " %d", value );

	printf( "\n" );
	va_end(ap);
}

#ifndef USE_FORK_TO_CHECK
static jmp_buf check_env;
static int bSignal;
#if defined (UNX) || defined (OS2)
void SignalHandler( int sig )
#else
void __cdecl SignalHandler( int sig )
#endif
{
  bSignal = 1;
  /*
  fprintf( stderr, "Signal %d caught\n", sig );
  signal( sig,	SignalHandler );
  */
  longjmp( check_env, sig );
}
#endif

int check( TestFunc func, Type eT, void* p )
{
#ifdef USE_FORK_TO_CHECK
  pid_t nChild = fork();
  if ( nChild )
  {
    int exitVal;
    wait( &exitVal );
    if ( exitVal & 0xff )
      return -1;
    else
      return exitVal >> 8;
  }
  else
  {
    exit( func( eT, p ) );
  }
#else
  int result;

  bSignal = 0;

  if ( !setjmp( check_env ) )
  {
	signal( SIGSEGV,	SignalHandler );
#ifdef UNX
	signal( SIGBUS,	SignalHandler );
#else
#endif
	result = func( eT, p );
	signal( SIGSEGV,	SIG_DFL );
#ifdef UNX
	signal( SIGBUS,	SIG_DFL );
#else
#endif
  }

  if ( bSignal )
	return -1;
  else
	return 0;
#endif
}

#endif


int GetAtAddress( Type eT, void* p )
{
  switch ( eT )
  {
  case t_char:		return *((char*)p);
  case t_short:		return *((short*)p);
  case t_int:		return *((int*)p);
  case t_long:		return *((long*)p);
  case t_double:	return *((double*)p);
  }
  abort();
}

int SetAtAddress( Type eT, void* p )
{
  switch ( eT )
  {
  case t_char:		return *((char*)p)	= 0;
  case t_short:		return *((short*)p)	= 0;
  case t_int:		return *((int*)p)	= 0;
  case t_long:		return *((long*)p)	= 0;
  case t_double:	return *((double*)p)= 0;
  }
  abort();
}

char* TypeName( Type eT )
{
  switch ( eT )
  {
  case t_char:		return "char";
  case t_short:		return "short";
  case t_int:		return "int";
  case t_long:		return "long";
  case t_double:	return "double";
  }
  abort();
}

int CheckGetAccess( Type eT, void* p )
{
  int b;
  b = -1 != check( (TestFunc)GetAtAddress, eT, p );
#if OSL_DEBUG_LEVEL > 1
  fprintf( stderr,
		   "%s read %s at %p\n",
		   (b? "can" : "can not" ), TypeName(eT), p );
#endif
  return b;
}
int CheckSetAccess( Type eT, void* p )
{
  int b;
  b = -1 != check( (TestFunc)SetAtAddress, eT, p );
#if OSL_DEBUG_LEVEL > 1
  fprintf( stderr,
		   "%s write %s at %p\n",
		   (b? "can" : "can not" ), TypeName(eT), p );
#endif
  return b;
}

int GetAlignment( Type eT )
{
  char	a[ 16*8 ];
  int	p = (int)(void*)&a;
  int	i;
  p = ( p + 0xF ) & ~0xF;
  for ( i = 1; i < 16; i++ )
	if ( CheckGetAccess( eT, (void*)(p+i) ) )
	  return i;
  return 0;
}

int CheckCharAccess( char* p )
{
  if ( CheckGetAccess( t_char, p ) )
    printf( "can read address %p\n", p );
  else
    printf( "can not read address %p\n", p );

  if ( CheckSetAccess( t_char, p ) )
    printf( "can write address %p\n", p );
  else
    printf( "can not write address %p\n", p );

  return 0;
}

struct Description
{
  int	bBigEndian;
  int	bStackGrowsDown;
  int	nStackAlignment;
  int	nAlignment[3];	/* 2,4,8 */
};

void Description_Ctor( struct Description* pThis )
{
  pThis->bBigEndian			= IsBigEndian();
  pThis->bStackGrowsDown	= IsStackGrowingDown();
  pThis->nStackAlignment	= GetStackAlignment();

  if ( sizeof(short) != 2 )
	abort();
  pThis->nAlignment[0] = GetAlignment( t_short );
  if ( sizeof(int) != 4 )
	abort();
  pThis->nAlignment[1] = GetAlignment( t_int );
  if ( sizeof(double) != 8 )
	abort();
  pThis->nAlignment[2] = GetAlignment( t_double );
}

void Description_Print( struct Description* pThis, char* name )
{
  int i;
  FILE* f = fopen( name, "w" );
  fprintf( f, "#define __%s\n",
		   pThis->bBigEndian ? "BIGENDIAN" : "LITTLEENDIAN" );
  for ( i = 0; i < 3; i++ )
	fprintf( f, "#define __ALIGNMENT%d\t%d\n",
			 1 << (i+1), pThis->nAlignment[i] );
  fprintf( f, "#define __STACKALIGNMENT wird nicht benutzt\t%d\n", pThis->nStackAlignment );
  fprintf( f, "#define __STACKDIRECTION\t%d\n",
		   pThis->bStackGrowsDown ? -1 : 1 );
  fprintf( f, "#define __SIZEOFCHAR\t%d\n", sizeof( char ) );
  fprintf( f, "#define __SIZEOFSHORT\t%d\n", sizeof( short ) );
  fprintf( f, "#define __SIZEOFINT\t%d\n", sizeof( int ) );
  fprintf( f, "#define __SIZEOFLONG\t%d\n", sizeof( long ) );
  fprintf( f, "#define __SIZEOFPOINTER\t%d\n", sizeof( void* ) );
  fprintf( f, "#define __SIZEOFDOUBLE\t%d\n", sizeof( double ) );
  fprintf( f, "#define __IEEEDOUBLE\n" );
  fprintf( f, "#define _SOLAR_NODESCRIPTION\n" );

  fclose(f);
}

int
#ifdef WNT
__cdecl
#endif
main( int argc, char* argv[] )
{
  printTypeSign( char, "char" );
  printTypeSign( short, "short" );
  printTypeSign( int, "int" );
  printTypeSign( long, "long" );

  printTypeSize( char, "char" );
  printTypeSize( short, "short" );
  printTypeSize( int, "int" );
  printTypeSize( long, "long" );
  printTypeSize( float, "float" );
  printTypeSize( double, "double" );
  printTypeSize( void *, "void *" );

  if ( IsBigEndian() )
    printf( "BIGENDIAN (Sparc, MC680x0, RS6000)\n" );
  else
    printf( "LITTLEENDIAN (Intel, VAX, PowerPC)\n" );

  if( IsStackGrowingDown() )
    printf( "Stack waechst nach unten\n" );
  else
    printf( "Stack waechst nach oben\n" );

  printf( "STACKALIGNMENT   : %d\n", GetStackAlignment() );

  PrintArgs( 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 );

  {
	char  a[64];
	int   i = 56;
	do
	{
	  printf( "Zugriff long auf %i-Aligned Adresse : ", i / 7 );
	  printf( ( CheckGetAccess( t_long, (long*)&a[i] ) ? "OK\n" : "ERROR\n" ) );
	  i >>= 1;
	} while( i >= 7 );
  }

  {
	char  a[64];
	int   i = 56;
	do
	{
	  printf( "Zugriff double auf %i-Aligned Adresse : ", i / 7 );
	  printf( ( CheckGetAccess( t_double, (double*)&a[i] ) ? "OK\n" : "ERROR\n" ) );
	  i >>= 1;
	} while( i >= 7 );
  }

  {
	char* p = NULL;
	CheckCharAccess( p );
	p = (char*)&p;
	CheckCharAccess( p );
  }

  if ( argc > 1 )
  {
	struct Description description;
	Description_Ctor( &description );
	Description_Print( &description, argv[1] );
  }

  exit( 0 );
  return 0;
}