view stitch/wrap.c @ 0:5242703e91d3 tip

Initial checkin for AIM92 aimR8.2 (last updated May 1997).

/*
    wrap.c
    ======

    encapsulate memory allocation for debugging en masse.

*/

#include "stitch.h"
#include "wrap.h"

#define LOGGING

/* linked list of framed allocations */

static struct _head *lastAllocated = (struct _head *) 0 ;


static void wraperr( id, hsz, tsz )
char *id ;
unsigned hsz, tsz ;
{
    printf( "memerr %s %d %d\n", id, hsz, tsz ) ;
}


Pointer wrap( mem, size, where )
char *mem ;
unsigned size ;
char where[] ;
{
    register struct _head *head = (struct _head *) mem ;
    register Pointer wrapped    = (Address) head + ROUNDUP( sizeof ( *head ) ) ;
    register struct _tail *tail = (struct _tail *) ( (Address) wrapped + ROUNDUP( size ) ) ;

#ifdef LOGGING
    (void) printf( "wrapping %x, %d bytes in %s\n", mem, size, where ) ;
#endif

    head->where = where ;
    head->size  = size  ;

    tail->size  = size  ;

    head->previous =  lastAllocated ;

    if( lastAllocated != 0 )
	lastAllocated->pointing = &head->previous ;

    lastAllocated = head ;
    lastAllocated->pointing = &lastAllocated ;

    return ( wrapped ) ;
}


Pointer unwrap( wrapped )
Pointer wrapped ;
{
    register struct _head *head = (struct _head *) ( (Address) wrapped - ROUNDUP( sizeof ( *head ) ) ) ;
    register struct _tail *tail = (struct _tail *) ( (Address) wrapped + ROUNDUP( head->size ) ) ;

#ifdef LOGGING
    (void) printf( "unwrapping %x, %d bytes in %s\n", head, head->size, head->where ) ;
#endif

    if( head->size != tail->size )
	wraperr( head->where, head->size, tail->size ) ;

    *head->pointing = head->previous ;

    if( head->previous != (struct _head *) 0 )
	head->previous->pointing = head->pointing ;

    return ( (char *) head ) ;
}

check_wrapping( printer )
{
    register struct _head *head = lastAllocated ;
    register Pointer wrapped ;
    register struct _tail *tail ;

    while( head != (struct _head *) 0 ) {

	wrapped = (Pointer) ( head + 1 ) ;

	tail = ( struct _tail * ) ( (Address) wrapped + ROUNDUP( head->size ) ) ;

	if( tail->size != head->size )
	    wraperr( head->where, head->size, tail->size ) ;

	head = head->previous ;
    }

    return ;
}

print_wrapping()
{
    register struct _head *head = lastAllocated ;
    register Pointer wrapped ;
    register struct _tail *tail ;

    while( head != (struct _head *) 0 ) {

	wrapped = (Pointer) ( head + 1 ) ;

	tail = (struct _tail *) ( (Address) wrapped + ROUNDUP( head->size ) ) ;

printf( "%d bytes \"%s\"\n", head->size, head->where ) ;
	if( tail->size != head->size )
	    wraperr( head->where, head->size, tail->size ) ;

	head = head->previous ;
    }

printf( "\n" ) ;

    return ;
}