MEMWATCH

V1.0

copyright@2006

email: mesmerli@hotmail.com

/*
** NOTE: Running this program in a Win32 or Unix environment
** will probably result in a segmentation fault or protection
** error. These errors may be caused by MEMWATCH when it is
** looking at memory to see if it owns it, or may be caused by
** the test program writing to memory it does not own.
**
** MEMWATCH has two functions called 'mwIsReadAddr()' and
** 'mwIsSafeAddr()', which are system-specific.
** If they are implemented for your system, and works
** correctly, MEMWATCH will identify garbage pointers and
** avoid causing segmentation faults, GP's etc.
**
** If they are NOT implemented, count on getting the core
** dumped when running this test program! As of this writing,
** the safe-address checking has been implemented for Win32
** and ANSI-C compliant systems. The ANSI-C checking traps
** SIGSEGV and uses setjmp/longjmp to resume processing.
**
** Note for Win95 users: The Win32 IsBadReadPtr() and its
** similar functions can return incorrect values. This has
** not happened under WinNT, though, just Win95.
**
** 991009 Johan Lindh
**
*/

#include <stdio.h>
#include <signal.h>
#include "memwatch.h"

#ifndef SIGSEGV
#error "SIGNAL.H does not define SIGSEGV; running this program WILL cause a core dump/crash!"
#endif

#ifndef MEMWATCH
#error "You really, really don't want to run this without memwatch. Trust me."
#endif

#if !defined(MW_STDIO) && !defined(MEMWATCH_STDIO)
#error "Define MW_STDIO and try again, please."
#endif

int main()
{
char *p;

/* Collect stats on a line number basis */
mwStatistics( 2 );

/* Slows things down, but OK for this test prg */
/* mwAutoCheck( 1 ); */

TRACE("Hello world!n");

p = malloc(210);
free(p);
p = malloc(20);
p = malloc(200); /* causes unfreed error */
p[-1] = 0; /* causes underflow error */
free(p);

p = malloc(100);
p[ -(int)(sizeof(long)*8) ] = -1; /* try to damage MW's heap chain */
free( p ); /* should cause relink */

mwSetAriFunc( mwAriHandler );
// ASSERT(1==2);

mwLimit(1000000);
mwNoMansLand( MW_NML_ALL );

/* These may cause a general protection fault (segmentation fault) */
/* They're here to help test the no-mans-land protection */
if( mwIsSafeAddr(p+50000,1) ) {
TRACE("Killing byte at %pn", p+50000);
*(p+50000) = 0;
}
if( mwIsSafeAddr(p+30000,1) ) {
TRACE("Killing byte at %pn", p+30000);
*(p+30000) = 0;
}
if( mwIsSafeAddr(p+1000,1) ) {
TRACE("Killing byte at %pn", p+1000);
*(p+1000) = 0;
}
if( mwIsSafeAddr(p-100,1) ) {
TRACE("Killing byte at %pn", p-100);
*(p-100) = 0;
}

/* This may cause a GP fault as well, since MW data buffers */
/* have been damaged in the above killing spree */
CHECK();

p = malloc(12000);
p[-5] = 1;
p[-10] = 2;
p[-15] = 3;
p[-20] = 4;

/* This may cause a GP fault since MW's buffer list may have */
/* been damaged by above killing, and it will try to repair it. */
free(p);

p = realloc(p,10); /* causes realloc: free'd from error */

/* May cause GP since MW will inspect the memory to see if it owns it. */
free( (void*)main );

return 0;
}

/* Comment out the following line to compile. */
//#error "Hey! Don't just compile this program, read the comments first!"

Makefile_Cross

CROSS_COMPILE = arm-linux-

AS = $(CROSS_COMPILE)as
LD = $(CROSS_COMPILE)ld
CC = $(CROSS_COMPILE)gcc
CPP = $(CC) -E
AR = $(CROSS_COMPILE)ar

CFLAGS= -O0 -gdwarf-2 -DHAVE_CONFIG_H -DFPM_DEFAULT -Dlinux -Dunix -DNDEBUG -D_REENTRANT -I.

ALL= test_Cross.exe

test_Cross.exe:
$(CC) -o $@ -DMEMWATCH -DMW_STDIO test.c memwatch.c

clean:
@rm -f $(ALL) *~ *.o