/** 
   -- The Optional Memory Allocation Word Set
   
    Copyright (C) Tektronix, Inc. 1998 - 2001. All rights reserved.
  
    @see     GNU LGPL
    @author  Tektronix CTE              @(#) %derived_by: guidod %
    @version %version: 5.6 %
      (%date_modified: Mon Mar 12 10:32:31 2001 %)
  
    @description
       The optional memory allocation wordset interfaces to
       the surrounding OS heap memory management.
 */
/*@{*/
#if defined(__version_control__) && defined(__GNUC__)
static char* id __attribute__((unused)) = 
"@(#) $Id: %full_filespec: memory-alloc-ext.c~5.6:csrc:bln_12xx!1 % $";
#endif

#define _P4_SOURCE 1

#include <pfe/pfe-base.h>
#include <pfe/def-xtra.h>

#include <stdlib.h>
#include <errno.h>

#include <pfe/_missing.h>
#include <pfe/logging.h>

/** ALLOCATE ( size -- ptr|0 code )
   allocate a chunk of memory from the system heap.
   use => FREE to release the memory area back to the system. <br>
   a code of zero means success.
 */
FCode (p4_allocate)
{
    errno = 0;
    if ((*SP = (p4cell) p4_calloc (1, (size_t) * SP)) != 0)
        *--SP = 0;
    else *--SP = errno;
}


/** FREE ( ptr -- code )
   free the memory from => ALLOCATE
   a code of zero means success.
 */
FCode (p4_free)
{
    errno = 0;
    
{ p4_xfree (*(void **) SP); }

    *SP = errno;
}


/** RESIZE ( ptr newsize -- ptr' code )
   resize the system memory chunk.
   a code of zero means success.
 */
FCode (p4_resize)
{
    void *p;
  
    errno = 0;
    p = realloc ((void *) SP[1], (size_t) SP[0]);
    
    if (p == NULL)
    
{
        SP[0] = errno;
    }
else
{          
        P4_debug2 (14, "realloc %p -> %p", (void*)SP[1], p);
        SP[0] = 0;
        SP[1] = (p4cell) p;
    }

}


P4_LISTWORDS (memory) =
{
    P4_INTO ("[ANS]", 0),
    P4_FXco ("ALLOCATE",	p4_allocate),
    P4_FXco ("FREE",		p4_free),
    P4_FXco ("RESIZE",		p4_resize),

    P4_INTO ("ENVIRONMENT", 0 ),
    P4_OCON ("MEMORY-ALLOC-EXT",	1994 ),
    
}
;
P4_COUNTWORDS (memory, "Memory-Alloc extension");

/*@}*/