1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
# calloc.m4 serial 27
# Copyright (C) 2004-2021 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
# 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.
# _AC_FUNC_CALLOC_IF([IF-WORKS], [IF-NOT])
# -------------------------------------
# If calloc is compatible with GNU calloc, run IF-WORKS, otherwise, IF-NOT.
AC_DEFUN([_AC_FUNC_CALLOC_IF],
[
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether calloc (0, n) and calloc (n, 0) return nonnull],
[ac_cv_func_calloc_0_nonnull],
[if test $cross_compiling != yes; then
ac_cv_func_calloc_0_nonnull=yes
AC_RUN_IFELSE(
[AC_LANG_PROGRAM(
[AC_INCLUDES_DEFAULT],
[[int result = 0;
char * volatile p = calloc (0, 0);
if (!p)
result |= 1;
free (p);
return result;
]])],
[],
[ac_cv_func_calloc_0_nonnull=no])
else
case "$host_os" in
# Guess yes on glibc systems.
*-gnu* | gnu*) ac_cv_func_calloc_0_nonnull="guessing yes" ;;
# Guess yes on musl systems.
*-musl*) ac_cv_func_calloc_0_nonnull="guessing yes" ;;
# Guess yes on native Windows.
mingw*) ac_cv_func_calloc_0_nonnull="guessing yes" ;;
# If we don't know, obey --enable-cross-guesses.
*) ac_cv_func_calloc_0_nonnull="$gl_cross_guess_normal" ;;
esac
fi
])
AS_CASE([$ac_cv_func_calloc_0_nonnull], [*yes], [$1], [$2])
])
# gl_FUNC_CALLOC_GNU
# ------------------
# Replace calloc if it is not compatible with GNU libc.
AC_DEFUN([gl_FUNC_CALLOC_GNU],
[
AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
AC_REQUIRE([gl_FUNC_CALLOC_POSIX])
if test $REPLACE_CALLOC = 0; then
_AC_FUNC_CALLOC_IF([], [REPLACE_CALLOC=1])
fi
])# gl_FUNC_CALLOC_GNU
# gl_FUNC_CALLOC_POSIX
# --------------------
# Test whether 'calloc' is POSIX compliant (sets errno to ENOMEM when it
# fails, and doesn't mess up with ptrdiff_t or size_t overflow),
# and replace calloc if it is not.
AC_DEFUN([gl_FUNC_CALLOC_POSIX],
[
AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
AC_REQUIRE([gl_FUNC_MALLOC_POSIX])
if test $REPLACE_MALLOC = 1; then
REPLACE_CALLOC=1
fi
dnl Although in theory we should also test for size_t overflow,
dnl in practice testing for ptrdiff_t overflow suffices
dnl since PTRDIFF_MAX <= SIZE_MAX on all known Gnulib porting targets.
dnl A separate size_t test would slow down 'configure'.
])
|
