spot/lib/xalloc-oversized.h
Alexandre Duret-Lutz 35129e5a5a gnulib: Add modules argmatch and isatty.
* lib/argmatch.c, lib/argmatch.h, lib/c-ctype.c, lib/c-ctype.h,
lib/config.charset, lib/c-strcasecmp.c, lib/c-strcaseeq.h,
lib/c-strcase.h, lib/c-strncasecmp.c, lib/exitfail.c, lib/exitfail.h,
lib/isatty.c, lib/localcharset.c, lib/localcharset.h, lib/mbrtowc.c,
lib/mbsinit.c, lib/quotearg.c, lib/quotearg.h, lib/quote.h,
lib/ref-add.sin, lib/ref-del.sin, lib/streq.h, lib/wctype-h.c,
lib/wctype.in.h, lib/xalloc-die.c, lib/xalloc.h, lib/xalloc-oversized.h,
lib/xmalloc.c, m4/codeset.m4, m4/configmake.m4, m4/glibc21.m4,
m4/isatty.m4, m4/localcharset.m4, m4/locale-fr.m4, m4/locale-ja.m4,
m4/locale-zh.m4, m4/mbrtowc.m4, m4/mbsinit.m4, m4/mbstate_t.m4,
m4/quotearg.m4, m4/quote.m4, m4/wctype_h.m4, m4/xalloc.m4: New files.
* lib/Makefile.am, m4/gnulib-cache.m4, m4/gnulib-comp.m4: Update.
2013-07-29 01:14:37 +02:00

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C

/* xalloc-oversized.h -- memory allocation size checking
Copyright (C) 1990-2000, 2003-2004, 2006-2013 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */
#ifndef XALLOC_OVERSIZED_H_
# define XALLOC_OVERSIZED_H_
# include <stddef.h>
/* 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 a 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))
#endif /* !XALLOC_OVERSIZED_H_ */