Mercurial > hg > octave-nkf > gnulib-hg
changeset 5465:f0ee86da74a7
(_AC_FUNC_CALLOC_IF): Check for buggy calloc implementations
that mishandle size_t overflow.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Wed, 17 Nov 2004 23:07:25 +0000 |
parents | f7677662318c |
children | 19276ed23d4a |
files | m4/calloc.m4 |
diffstat | 1 files changed, 24 insertions(+), 11 deletions(-) [+] |
line wrap: on
line diff
--- a/m4/calloc.m4 +++ b/m4/calloc.m4 @@ -1,6 +1,25 @@ -#serial 2 +# calloc.m4 serial 3 + +# Copyright (C) 2004 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. -# Determine whether calloc (N, S) returns non-NULL when N*S is zero. +# 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. + +# Written by Jim Meyering. + +# Determine whether calloc (N, S) returns non-NULL when N*S is zero, +# and returns NULL when N*S overflows. # If so, define HAVE_CALLOC. Otherwise, define calloc to rpl_calloc # and arrange to use a calloc wrapper function that does work in that case. @@ -9,17 +28,11 @@ # If `calloc (0, 0)' is properly handled, run IF-WORKS, otherwise, IF-NOT. AC_DEFUN([_AC_FUNC_CALLOC_IF], [AC_REQUIRE([AC_HEADER_STDC])dnl +AC_REQUIRE([AC_TYPE_SIZE_T])dnl AC_CHECK_HEADERS(stdlib.h) AC_CACHE_CHECK([for GNU libc compatible calloc], ac_cv_func_calloc_0_nonnull, -[AC_RUN_IFELSE( -[AC_LANG_PROGRAM( -[[#if STDC_HEADERS || HAVE_STDLIB_H -# include <stdlib.h> -#else -char *calloc (); -#endif -]], - [exit (calloc (0, 0) ? 0 : 1);])], +[AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT], + [exit (!calloc (0, 0) || calloc ((size_t) -1 / 8 + 1, 8));])], [ac_cv_func_calloc_0_nonnull=yes], [ac_cv_func_calloc_0_nonnull=no], [ac_cv_func_calloc_0_nonnull=no])])