-# strsignal.m4 serial 1
-dnl Copyright (C) 2008 Free Software Foundation, Inc.
+# strsignal.m4 serial 5
+dnl Copyright (C) 2008-2011 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 Persuade glibc <string.h> to declare strsignal().
AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
- AC_REQUIRE([AC_DECL_SYS_SIGLIST])
-
AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
- AC_REPLACE_FUNCS([strsignal])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
AC_CHECK_DECLS_ONCE([strsignal])
if test $ac_cv_have_decl_strsignal = no; then
HAVE_DECL_STRSIGNAL=0
+ fi
+
+ AC_CHECK_FUNCS([strsignal])
+ if test $ac_cv_func_strsignal = yes; then
+ dnl Check if strsignal behaves reasonably for out-of-range signal numbers.
+ dnl On Solaris it returns NULL; on AIX 5.1 it returns (char *) -1.
+ AC_CACHE_CHECK([whether strsignal always returns a string],
+ [gl_cv_func_working_strsignal],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <string.h>
+#include <unistd.h> /* NetBSD 5.0 declares it in wrong header. */
+ ]],
+ [[int result = 0;
+ char *s = strsignal (-1);
+ if (s == (char *) 0)
+ result |= 1;
+ if (s == (char *) -1)
+ result |= 2;
+ return result;
+ ]])],
+ [gl_cv_func_working_strsignal=yes],
+ [gl_cv_func_working_strsignal=no],
+ [case "$host_os" in
+ solaris* | aix*) gl_cv_func_working_strsignal=no;;
+ *) gl_cv_func_working_strsignal="guessing yes";;
+ esac])])
+ else
+ gl_cv_func_working_strsignal=no
+ fi
+
+ if test "$gl_cv_func_working_strsignal" = no; then
+ if test $ac_cv_func_strsignal = yes; then
+ REPLACE_STRSIGNAL=1
+ fi
+ AC_LIBOBJ([strsignal])
gl_PREREQ_STRSIGNAL
fi
])
# Prerequisites of lib/strsignal.c.
-AC_DEFUN([gl_PREREQ_STRSIGNAL], [:])
+AC_DEFUN([gl_PREREQ_STRSIGNAL], [
+ AC_REQUIRE([AC_DECL_SYS_SIGLIST])
+ AC_CHECK_DECLS([_sys_siglist], [], [], [#include <signal.h>])
+])