freebsd-dev/contrib/diff/lib/xalloc.h
2007-06-15 07:06:13 +00:00

88 lines
3.5 KiB
C

/* xalloc.h -- malloc with out-of-memory checking
Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
1999, 2000, 2003 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#ifndef XALLOC_H_
# define XALLOC_H_
# include <stddef.h>
# ifndef __attribute__
# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
# define __attribute__(x)
# endif
# endif
# ifndef ATTRIBUTE_NORETURN
# define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
# endif
/* If this pointer is non-zero, run the specified function upon each
allocation failure. It is initialized to zero. */
extern void (*xalloc_fail_func) (void);
/* If XALLOC_FAIL_FUNC is undefined or a function that returns, this
message is output. It is translated via gettext.
Its value is "memory exhausted". */
extern char const xalloc_msg_memory_exhausted[];
/* This function is always triggered when memory is exhausted. It is
in charge of honoring the two previous items. It exits with status
exit_failure (defined in exitfail.h). This is the
function to call when one wants the program to die because of a
memory allocation failure. */
extern void xalloc_die (void) ATTRIBUTE_NORETURN;
void *xmalloc (size_t s);
void *xnmalloc (size_t n, size_t s);
void *xzalloc (size_t s);
void *xcalloc (size_t n, size_t s);
void *xrealloc (void *p, size_t s);
void *xnrealloc (void *p, size_t n, size_t s);
void *x2realloc (void *p, size_t *pn);
void *x2nrealloc (void *p, size_t *pn, size_t s);
void *xclone (void const *p, size_t s);
char *xstrdup (const char *str);
/* Return 1 if an array of N objects, each of size S, cannot exist due
to size arithmetic overflow. S must be positive and N must be
nonnegative. This is a macro, not an inline function, so that it
works correctly even when SIZE_MAX < N.
By gnulib convention, SIZE_MAX represents overflow in size
calculations, so the conservative dividend to use here is
SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
However, malloc (SIZE_MAX) fails on all known hosts where
sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
exactly-SIZE_MAX allocations on such hosts; this avoids a test and
branch when S is known to be 1. */
# define xalloc_oversized(n, s) \
((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
/* These macros are deprecated; they will go away soon, and are retained
temporarily only to ease conversion to the functions described above. */
# define CCLONE(p, n) xclone (p, (n) * sizeof *(p))
# define CLONE(p) xclone (p, sizeof *(p))
# define NEW(type, var) type *var = xmalloc (sizeof (type))
# define XCALLOC(type, n) xcalloc (n, sizeof (type))
# define XMALLOC(type, n) xnmalloc (n, sizeof (type))
# define XREALLOC(p, type, n) xnrealloc (p, n, sizeof (type))
# define XFREE(p) free (p)
#endif /* !XALLOC_H_ */