# strerror_r.m4 serial 19
dnl Copyright (C) 2002, 2007-2017 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_FUNC_STRERROR_R],
[
AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
AC_REQUIRE([gl_FUNC_STRERROR_R_WORKS])
dnl Persuade Solaris <string.h> to declare strerror_r().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
dnl Some systems don't declare strerror_r() if _THREAD_SAFE and _REENTRANT
dnl are not defined.
AC_CHECK_DECLS_ONCE([strerror_r])
if test $ac_cv_have_decl_strerror_r = no; then
HAVE_DECL_STRERROR_R=0
fi
if test $ac_cv_func_strerror_r = yes; then
if test "$ERRNO_H:$REPLACE_STRERROR_0" = :0; then
if test $gl_cv_func_strerror_r_posix_signature = yes; then
case "$gl_cv_func_strerror_r_works" in
dnl The system's strerror_r has bugs. Replace it.
*no) REPLACE_STRERROR_R=1 ;;
esac
else
dnl The system's strerror_r() has a wrong signature. Replace it.
REPLACE_STRERROR_R=1
fi
else
dnl The system's strerror_r() cannot know about the new errno values we
dnl add to <errno.h>, or any fix for strerror(0). Replace it.
REPLACE_STRERROR_R=1
fi
fi
])
# Prerequisites of lib/strerror_r.c.
AC_DEFUN([gl_PREREQ_STRERROR_R], [
dnl glibc >= 2.3.4 and cygwin 1.7.9 have a function __xpg_strerror_r.
AC_CHECK_FUNCS_ONCE([__xpg_strerror_r])
AC_CHECK_FUNCS_ONCE([catgets])
AC_CHECK_FUNCS_ONCE([snprintf])
])
# Detect if strerror_r works, but without affecting whether a replacement
# strerror_r will be used.
AC_DEFUN([gl_FUNC_STRERROR_R_WORKS],
[
AC_REQUIRE([gl_HEADER_ERRNO_H])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_REQUIRE([gl_FUNC_STRERROR_0])
AC_CHECK_FUNCS_ONCE([strerror_r])
if test $ac_cv_func_strerror_r = yes; then
if test "$ERRNO_H:$REPLACE_STRERROR_0" = :0; then
dnl The POSIX prototype is: int strerror_r (int, char *, size_t);
dnl glibc, Cygwin: char *strerror_r (int, char *, size_t);
dnl AIX 5.1, OSF/1 5.1: int strerror_r (int, char *, int);
AC_CACHE_CHECK([for strerror_r with POSIX signature],
[gl_cv_func_strerror_r_posix_signature],
[AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM(
[[#include <string.h>
int strerror_r (int, char *, size_t);
]],
[])],
[gl_cv_func_strerror_r_posix_signature=yes],
[gl_cv_func_strerror_r_posix_signature=no])
])
if test $gl_cv_func_strerror_r_posix_signature = yes; then
dnl AIX 6.1 strerror_r fails by returning -1, not an error number.
dnl HP-UX 11.31 strerror_r always fails when the buffer length argument
dnl is less than 80.
dnl FreeBSD 8.s strerror_r claims failure on 0
dnl Mac OS X 10.5 strerror_r treats 0 like -1
dnl Solaris 10 strerror_r corrupts errno on failure
AC_CACHE_CHECK([whether strerror_r works],
[gl_cv_func_strerror_r_works],
[AC_RUN_IFELSE(
[AC_LANG_PROGRAM(
[[#include <errno.h>
#include <string.h>
]],
[[int result = 0;
char buf[79];
if (strerror_r (EACCES, buf, 0) < 0)
result |= 1;
errno = 0;
if (strerror_r (EACCES, buf, sizeof buf) != 0)
result |= 2;
strcpy (buf, "Unknown");
if (strerror_r (0, buf, sizeof buf) != 0)
result |= 4;
if (errno)
result |= 8;
if (strstr (buf, "nknown") || strstr (buf, "ndefined"))
result |= 0x10;
errno = 0;
*buf = 0;
if (strerror_r (-3, buf, sizeof buf) < 0)
result |= 0x20;
if (errno)
result |= 0x40;
if (!*buf)
result |= 0x80;
return result;
]])],
[gl_cv_func_strerror_r_works=yes],
[gl_cv_func_strerror_r_works=no],
[
changequote(,)dnl
case "$host_os" in
# Guess no on AIX.
aix*) gl_cv_func_strerror_r_works="guessing no";;
# Guess no on HP-UX.
hpux*) gl_cv_func_strerror_r_works="guessing no";;
# Guess no on BSD variants.
*bsd*) gl_cv_func_strerror_r_works="guessing no";;
# Guess yes otherwise.
*) gl_cv_func_strerror_r_works="guessing yes";;
esac
changequote([,])dnl
])
])
else
dnl The system's strerror() has a wrong signature.
dnl glibc >= 2.3.4 and cygwin 1.7.9 have a function __xpg_strerror_r.
AC_CHECK_FUNCS_ONCE([__xpg_strerror_r])
dnl In glibc < 2.14, __xpg_strerror_r does not populate buf on failure.
dnl In cygwin < 1.7.10, __xpg_strerror_r clobbers strerror's buffer.
if test $ac_cv_func___xpg_strerror_r = yes; then
AC_CACHE_CHECK([whether __xpg_strerror_r works],
[gl_cv_func_strerror_r_works],
[AC_RUN_IFELSE(
[AC_LANG_PROGRAM(
[[#include <errno.h>
#include <string.h>
extern
#ifdef __cplusplus
"C"
#endif
int __xpg_strerror_r(int, char *, size_t);
]],
[[int result = 0;
char buf[256] = "^";
char copy[256];
char *str = strerror (-1);
strcpy (copy, str);
if (__xpg_strerror_r (-2, buf, 1) == 0)
result |= 1;
if (*buf)
result |= 2;
__xpg_strerror_r (-2, buf, 256);
if (strcmp (str, copy))
result |= 4;
return result;
]])],
[gl_cv_func_strerror_r_works=yes],
[gl_cv_func_strerror_r_works=no],
[dnl Guess no on all platforms that have __xpg_strerror_r,
dnl at least until fixed glibc and cygwin are more common.
gl_cv_func_strerror_r_works="guessing no"
])
])
fi
fi
fi
fi
])