-#serial 1
+# strerror_r.m4 serial 13
+dnl Copyright (C) 2002, 2007-2011 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.
-dnl From Jim Meyering.
-dnl Determine whether the strerror_r implementation is one of
-dnl the broken ones that returns `int' rather than `char*'.
-dnl Actually, this tests only whether it returns a scalar
-dnl or an array, but that should be enough.
-dnl On at least DEC UNIX 4.0[A-D], strerror_r returns `int'.
-dnl This is used by lib/error.c.
+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
+])
-AC_DEFUN(jm_FUNC_STRERROR_R,
+# 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])
+])
+
+# Detect if strerror_r works, but without affecting whether a replacement
+# strerror_r will be used.
+AC_DEFUN([gl_FUNC_STRERROR_R_WORKS],
[
- # Check strerror_r
- AC_CHECK_FUNCS([strerror_r])
+ 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
- AC_CHECK_HEADERS(string.h)
- AC_CACHE_CHECK([for working strerror_r],
- jm_cv_func_working_strerror_r,
- [
- AC_TRY_COMPILE(
- [
-# include <stdio.h>
-# if HAVE_STRING_H
-# include <string.h>
-# endif
- ],
- [
- int buf; /* avoiding square brackets makes this easier */
- char x = *strerror_r (0, buf, sizeof buf);
- ],
- jm_cv_func_working_strerror_r=yes,
- jm_cv_func_working_strerror_r=no
- )
- if test $jm_cv_func_working_strerror_r = yes; then
- AC_DEFINE_UNQUOTED(HAVE_WORKING_STRERROR_R, 1,
- [Define to 1 if strerror_r returns a string.])
+ if test "$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 $gl_cv_func_strerror_r_posix_signature = yes; then
+ dnl AIX 6.1 strerror_r fails by returning -1, not an error number.
+ dnl HP-UX 11.31 strerror_r always fails when the buffer length argument
+ dnl is less than 80.
+ dnl FreeBSD 8.s strerror_r claims failure on 0
+ dnl MacOS X 10.5 strerror_r treats 0 like -1
+ dnl Solaris 10 strerror_r corrupts errno on failure
+ AC_CACHE_CHECK([whether strerror_r works],
+ [gl_cv_func_strerror_r_works],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <errno.h>
+ #include <string.h>
+ ]],
+ [[int result = 0;
+ char buf[79];
+ if (strerror_r (EACCES, buf, 0) < 0)
+ result |= 1;
+ errno = 0;
+ if (strerror_r (EACCES, buf, sizeof buf) != 0)
+ result |= 2;
+ strcpy (buf, "Unknown");
+ if (strerror_r (0, buf, sizeof buf) != 0)
+ result |= 4;
+ if (errno)
+ result |= 8;
+ if (strstr (buf, "nknown") || strstr (buf, "ndefined"))
+ result |= 0x10;
+ errno = 0;
+ *buf = 0;
+ if (strerror_r (-3, buf, sizeof buf) < 0)
+ result |= 0x20;
+ if (errno)
+ result |= 0x40;
+ if (!*buf)
+ result |= 0x80;
+ return result;
+ ]])],
+ [gl_cv_func_strerror_r_works=yes],
+ [gl_cv_func_strerror_r_works=no],
+ [
+changequote(,)dnl
+ case "$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
])