/* Implementation to allow compilation of GNU objc code with NeXT runtime
   Copyright (C) 1993,1994 Free Software Foundation, Inc.

   Author: Kresten Krab Thorup
   Modified by: Andrew Kachites McCallum <mccallum@gnu.ai.mit.edu>
   Date: Sep 1994

   This file is part of the GNUstep Base Library.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
   
   This library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with this library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA.
*/ 

#include "config.h"
#include <stdio.h>
#include <base/preface.h>
#include "mframe.h"

#ifndef ROUND
#define ROUND(V, A) \
  ({ typeof(V) __v=(V); typeof(A) __a=(A); \
     __a*((__v+__a-1)/__a); })
#endif

/*
  return the size of an object specified by type 
*/

int
objc_sizeof_type(const char* type)
{
  switch(*type) {
  case _C_ID:
    return sizeof(id);
    break;

  case _C_CLASS:
    return sizeof(Class);
    break;

  case _C_SEL:
    return sizeof(SEL);
    break;

  case _C_CHR:
    return sizeof(char);
    break;
    
  case _C_UCHR:
    return sizeof(unsigned char);
    break;

  case _C_SHT:
    return sizeof(short);
    break;

  case _C_USHT:
    return sizeof(unsigned short);
    break;

  case _C_INT:
    return sizeof(int);
    break;

  case _C_UINT:
    return sizeof(unsigned int);
    break;

  case _C_LNG:
    return sizeof(long);
    break;

  case _C_ULNG:
    return sizeof(unsigned long);
    break;

  case _C_FLT:
    return sizeof(float);
    break;

  case _C_DBL:
    return sizeof(double);
    break;

  case _C_PTR:
  case _C_ATOM:
  case _C_CHARPTR:
    return sizeof(char*);
    break;

  case _C_ARY_B:
    {
      int len = atoi(type+1);
      while (isdigit(*++type));
      return len*objc_aligned_size (type);
    }
    break; 

  case _C_STRUCT_B:
    {
      int acc_size = 0;
      int align;
      while (*type != _C_STRUCT_E && *type++ != '='); /* skip "<name>=" */
      while (*type != _C_STRUCT_E)
	{
	  align = objc_alignof_type (type);       /* padd to alignment */
	  acc_size = ROUND (acc_size, align);
	  acc_size += objc_sizeof_type (type);   /* add component size */
	  type = objc_skip_typespec (type);	         /* skip component */
	}
      return acc_size;
    }

  case _C_UNION_B:
    {
      int max_size = 0;
      while (*type != _C_UNION_E && *type++ != '=') /* do nothing */;
      while (*type != _C_UNION_E)
	{
	  max_size = MAX (max_size, objc_sizeof_type (type));
	  type = objc_skip_typespec (type);
	}
      return max_size;
    }
    
  default:
    abort();
  }
}


/*
  Return the alignment of an object specified by type 
*/

int
objc_alignof_type(const char* type)
{
  switch(*type) {
  case _C_ID:
    return __alignof__(id);
    break;

  case _C_CLASS:
    return __alignof__(Class);
    break;
    
  case _C_SEL:
    return __alignof__(SEL);
    break;

  case _C_CHR:
    return __alignof__(char);
    break;
    
  case _C_UCHR:
    return __alignof__(unsigned char);
    break;

  case _C_SHT:
    return __alignof__(short);
    break;

  case _C_USHT:
    return __alignof__(unsigned short);
    break;

  case _C_INT:
    return __alignof__(int);
    break;

  case _C_UINT:
    return __alignof__(unsigned int);
    break;

  case _C_LNG:
    return __alignof__(long);
    break;

  case _C_ULNG:
    return __alignof__(unsigned long);
    break;

  case _C_FLT:
    return __alignof__(float);
    break;

  case _C_DBL:
    return __alignof__(double);
    break;

  case _C_ATOM:
  case _C_CHARPTR:
    return __alignof__(char*);
    break;

  case _C_ARY_B:
    while (isdigit(*++type)) /* do nothing */;
    return objc_alignof_type (type);
      
  case _C_STRUCT_B:
    {
      struct { int x; double y; } fooalign;
      while(*type != _C_STRUCT_E && *type++ != '=') /* do nothing */;
      if (*type != _C_STRUCT_E)
	return MAX (objc_alignof_type (type), __alignof__ (fooalign));
      else
	return __alignof__ (fooalign);
    }

  case _C_UNION_B:
    {
      int maxalign = 0;
      while (*type != _C_UNION_E && *type++ != '=') /* do nothing */;
      while (*type != _C_UNION_E)
	{
	  maxalign = MAX (maxalign, objc_alignof_type (type));
	  type = objc_skip_typespec (type);
	}
      return maxalign;
    }
    
  default:
    abort();
  }
}

/*
  The aligned size if the size rounded up to the nearest alignment.
*/

int
objc_aligned_size (const char* type)
{
  int size = objc_sizeof_type (type);
  int align = objc_alignof_type (type);
  return ROUND (size, align);
}

/*
  The size rounded up to the nearest integral of the wordsize, taken
  to be the size of a void*.
*/

int 
objc_promoted_size (const char* type)
{
  int size = objc_sizeof_type (type);
  int wordsize = sizeof (void*);

  return ROUND (size, wordsize);
}

/*
  Skip type qualifiers.  These may eventually precede typespecs
  occuring in method prototype encodings.
*/

const char*
objc_skip_type_qualifiers (const char* type)
{
  while (*type == _C_CONST
	 || *type == _C_IN 
	 || *type == _C_INOUT
	 || *type == _C_OUT 
	 || *type == _C_BYCOPY
#ifdef	_C_BYREF
	 || *type == _C_BYREF
#endif
#ifdef	_C_GCINVISIBLE
	 || *type == _C_GCINVISIBLE
#endif
	 || *type == _C_ONEWAY)
    {
      type += 1;
    }
  return type;
}

  
/*
  Skip one typespec element.  If the typespec is prepended by type
  qualifiers, these are skipped as well.
*/

const char* 
objc_skip_typespec (const char* type)
{
  type = objc_skip_type_qualifiers (type);
  
  switch (*type) {

  case _C_ID:
    /* An id may be annotated by the actual type if it is known
       with the @"ClassName" syntax */

    if (*++type != '"')
      return type;
    else
      {
	while (*++type != '"') /* do nothing */;
	return type + 1;
      }

    /* The following are one character type codes */
  case _C_CLASS:
  case _C_SEL:
  case _C_CHR:
  case _C_UCHR:
  case _C_CHARPTR:
  case _C_ATOM:
  case _C_SHT:
  case _C_USHT:
  case _C_INT:
  case _C_UINT:
  case _C_LNG:
  case _C_ULNG:
  case _C_FLT:
  case _C_DBL:
  case _C_VOID:
    return ++type;
    break;

  case _C_ARY_B:
    /* skip digits, typespec and closing ']' */
    
    while(isdigit(*++type));
    type = objc_skip_typespec(type);
    if (*type == _C_ARY_E)
      return ++type;
    else
      abort();

  case _C_STRUCT_B:
    /* skip name, and elements until closing '}'  */
    
    while (*type != _C_STRUCT_E && *type++ != '=');
    while (*type != _C_STRUCT_E) { type = objc_skip_typespec (type); }
    return ++type;

  case _C_UNION_B:
    /* skip name, and elements until closing ')'  */
    
    while (*type != _C_UNION_E && *type++ != '=');
    while (*type != _C_UNION_E) { type = objc_skip_typespec (type); }
    return ++type;

  case _C_PTR:
    /* Just skip the following typespec */
    
    return objc_skip_typespec (++type);
    
  default:
    abort();
  }
}

/*
  Skip an offset as part of a method encoding.  This is prepended by a
  '+' if the argument is passed in registers.
*/
inline const char* 
objc_skip_offset (const char* type)
{
  if (*type == '+') type++;
  if (*type == '-') type++;
  while(isdigit(*++type));
  return type;
}

/*
  Skip an argument specification of a method encoding.
*/
const char*
objc_skip_argspec (const char* type)
{
  type = objc_skip_typespec (type);
  type = objc_skip_offset (type);
  return type;
}

unsigned
objc_get_type_qualifiers (const char* type)
{
  unsigned res = 0;
  BOOL flag = YES;

  while (flag)
    switch (*type++)
      {
      case _C_CONST:  res |= _F_CONST; break;
      case _C_IN:     res |= _F_IN; break;
      case _C_INOUT:  res |= _F_INOUT; break;
      case _C_OUT:    res |= _F_OUT; break;
      case _C_BYCOPY: res |= _F_BYCOPY; break;
#ifdef	_C_BYREF
      case _C_BYREF:  res |= _F_BYREF; break;
#endif
      case _C_ONEWAY: res |= _F_ONEWAY; break;
#ifdef	_C_GCINVISIBLE
      case _C_GCINVISIBLE:  res |= _F_GCINVISIBLE; break;
#endif
      default: flag = NO;
    }

  return res;
}

/* Returns YES iff t1 and t2 have same method types, but we ignore
   the argframe layout */
BOOL
sel_types_match (const char* t1, const char* t2)
{
  if (!t1 || !t2)
    return NO;
  while (*t1 && *t2)
    {
      if (*t1 == '+') t1++;
      if (*t1 == '-') t1++;
      if (*t2 == '+') t2++;
      if (*t2 == '-') t2++;
      while (isdigit(*t1)) t1++;
      while (isdigit(*t2)) t2++;
      /* xxx Remove these next two lines when qualifiers are put in
	  all selectors, not just Protocol selectors. */
      t1 = objc_skip_type_qualifiers(t1);
      t2 = objc_skip_type_qualifiers(t2);
      if (!*t1 && !*t2)
	return YES;
      if (*t1 != *t2)
	return NO;
      t1++;
      t2++;
    }
  return NO;
}

id next_objc_msg_sendv(id object, SEL op, void* frame)
{
  arglist_t  argFrame = __builtin_apply_args();
  struct objc_method *m = class_get_instance_method(object->class_pointer, op);
  const char *type;
  void       *result;

  argFrame->arg_ptr = frame;
  *((id*)method_types_get_first_argument (m, argFrame, &type)) = object;
  *((SEL*)method_types_get_next_argument (argFrame, &type)) = op;
  result = __builtin_apply((apply_t)m->method_imp,
                           argFrame,
                           method_get_sizeof_arguments (m));

#if !defined(BROKEN_BUILTIN_APPLY) && defined(i386)
    /* Special hack to avoid pushing the poped float value back to the fp
       stack on i386 machines. This happens with NeXT runtime and 2.7.2
       compiler. If the result value is floating point don't call
       __builtin_return anymore. */
    if(*m->method_types == _C_FLT || *m->method_types == _C_DBL) {
        long double value = *(long double*)(((char*)result) + 8);
        asm("fld %0" : : "f" (value));
    }
    else
#endif
  __builtin_return(result);
}

/*
** Hook functions for memory allocation and disposal.
** This makes it easy to substitute garbage collection systems
** such as Boehm's GC by assigning these function pointers
** to the GC's allocation routines.  By default these point
** to the ANSI standard malloc, realloc, free, etc.
**
** Users should call the normal objc routines above for
** memory allocation and disposal within their programs.
*/

void *(*_objc_malloc)(size_t) = malloc;
void *(*_objc_atomic_malloc)(size_t) = malloc;
void *(*_objc_valloc)(size_t) = malloc;
void *(*_objc_realloc)(void *, size_t) = realloc;
void *(*_objc_calloc)(size_t, size_t) = calloc;
void (*_objc_free)(void *) = free;

/*
** Standard functions for memory allocation and disposal.
** Users should use these functions in their ObjC programs so
** that they work properly with garbage collectors as well as
** can take advantage of the exception/error handling available.
*/

void *
objc_malloc(size_t size)
{
  void* res = (void*) (*_objc_malloc)(size);
  if(!res)
    objc_error(nil, OBJC_ERR_MEMORY, "Virtual memory exhausted\n");
  return res;
}

void *
objc_atomic_malloc(size_t size)
{
  void* res = (void*) (*_objc_atomic_malloc)(size);
  if(!res)
    objc_error(nil, OBJC_ERR_MEMORY, "Virtual memory exhausted\n");
  return res;
}

void *
objc_valloc(size_t size)
{
  void* res = (void*) (*_objc_valloc)(size);
  if(!res)
    objc_error(nil, OBJC_ERR_MEMORY, "Virtual memory exhausted\n");
  return res;
}

void *
objc_realloc(void *mem, size_t size)
{
  void* res = (void*) (*_objc_realloc)(mem, size);
  if(!res)
    objc_error(nil, OBJC_ERR_MEMORY, "Virtual memory exhausted\n");
  return res;
}

void *
objc_calloc(size_t nelem, size_t size)
{
  void* res = (void*) (*_objc_calloc)(nelem, size);
  if(!res)
    objc_error(nil, OBJC_ERR_MEMORY, "Virtual memory exhausted\n");
  return res;
}

void
objc_free(void *mem)
{
  (*_objc_free)(mem);
}

/*
** Error handler function
** NULL so that default is to just print to stderr
*/
static objc_error_handler _objc_error_handler = NULL;

/* Trigger an objc error */
void
objc_error(id object, int code, const char* fmt, ...)
{
  va_list ap;

  va_start(ap, fmt);
  objc_verror(object, code, fmt, ap);
  va_end(ap);
}

/* Trigger an objc error */
void
objc_verror(id object, int code, const char* fmt, va_list ap)
{
  BOOL result = NO;

  /* Call the error handler if its there
     Otherwise print to stderr */
  if (_objc_error_handler)
    result = (*_objc_error_handler)(object, code, fmt, ap);
  else
    vfprintf (stderr, fmt, ap);

  /* Continue if the error handler says its ok
     Otherwise abort the program */
  if (result)
    return;
  else
    abort();
}

/* Set the error handler */
objc_error_handler
objc_set_error_handler(objc_error_handler func)
{
  objc_error_handler temp = _objc_error_handler;
  _objc_error_handler = func;
  return temp;
}