xmalloc.c

/*
 * A safer saner malloc, for careless programmers
 * $Revision: 7.16 $
 */

#include <stdlib.h>
#include <limits.h>
#include "compat.h"
#include "sc.h"

static void fatal(char *);

#define	MAGIC	(double)1234567890.12344

void *
scxmalloc(size_t n)
{
	void *ptr;

	if ((ptr = malloc(n + sizeof(double))) == NULL)
		fatal("scxmalloc: no memory");
	*((double *) ptr) = MAGIC;		/* magic number */
	return(ptr + sizeof(double));
}

/* we make sure realloc will do a malloc if needed */
void *
scxrealloc(void *ptr, size_t n)
{
	if (ptr == NULL)
		return(scxmalloc(n));

	ptr -= sizeof(double);
	if (*((double *) ptr) != MAGIC)
		fatal("scxrealloc: storage not scxmalloc'ed");

	if ((ptr = realloc(ptr, n + sizeof(double))) == NULL)
		fatal("scxmalloc: no memory");
	*((double *) ptr) = MAGIC;		/* magic number */
	return(ptr + sizeof(double));
}

void
scxfree(void *p)
{
	if (p == NULL)
		fatal("scxfree: NULL");
	p -= sizeof(double);
	if (*((double *) p) != MAGIC)
		fatal("scxfree: storage not malloc'ed");
	free(p);
}

static void
fatal(char *str)
{
#ifndef PSC
    deraw(1);
#endif /* PSC */
    fprintf(stderr, "%s\n", str);
#ifndef PSC
    diesave();
#endif /* PSC */
    exit(1);
}