diff --git a/Makefile.am b/Makefile.am
index e768b53..c480e09 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -7,8 +7,9 @@ dist_doc_DATA = COPYING NEWS README
EXTRA_DIST = \
autogen.sh \
- m4/ccflags.m4 m4/libshout.m4 m4/libvorbis.m4 m4/libxml2.m4 \
- m4/progname.m4 m4/taglib.m4 m4/tree.m4 m4/vacopy.m4 m4/vars.m4
+ m4/attribute.m4 m4/ccflags.m4 m4/libshout.m4 m4/libvorbis.m4 \
+ m4/libxml2.m4 m4/progname.m4 m4/taglib.m4 m4/tree.m4 m4/vacopy.m4 \
+ m4/vars.m4
CLEANFILES = core *.core *~ .*~
diff --git a/configure.ac b/configure.ac
index d7157a3..31e671b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -81,6 +81,30 @@ else
esac
fi
+have_attributes=no
+CFG_ATTRIBUTE_UNUSED=0
+AX_FUNC_ATTRIBUTE_UNUSED([
+ CFG_ATTRIBUTE_UNUSED=1
+ have_attributes=yes
+], [])
+AC_SUBST([CFG_ATTRIBUTE_UNUSED])
+
+CFG_HAVE_ATTRIBUTES=0
+CFG_ATTRIBUTE_FORMAT=0
+CFG_ATTRIBUTE_NONNULL=0
+if test x"${have_attributes}" = "xyes"; then
+ CFG_HAVE_ATTRIBUTES=1
+ AX_FUNC_ATTRIBUTE([const char *a, ...],
+ [format], [(printf, 1, 2)],
+ [CFG_ATTRIBUTE_FORMAT=1], [])
+ AX_FUNC_ATTRIBUTE([const char *a],
+ [nonnull], [(1)],
+ [CFG_ATTRIBUTE_NONNULL=1], [])
+fi
+AC_SUBST([CFG_HAVE_ATTRIBUTES])
+AC_SUBST([CFG_ATTRIBUTE_FORMAT])
+AC_SUBST([CFG_ATTRIBUTE_NONNULL])
+
AC_C_CONST
AC_C_VOLATILE
@@ -268,6 +292,7 @@ AC_CONFIG_FILES([
examples/Makefile
m4/Makefile
src/Makefile
+ src/attr_config.h
src/ezstream-file.sh
])
diff --git a/m4/attribute.m4 b/m4/attribute.m4
new file mode 100644
index 0000000..eb4d7ff
--- /dev/null
+++ b/m4/attribute.m4
@@ -0,0 +1,113 @@
+dnl # $Id$
+
+dnl # Check if the compiler understands a certain __attribute__.
+
+
+dnl # Copyright (c) 2008 Moritz Grimm <mgrimm@mrsserver.net>
+dnl #
+dnl # Permission to use, copy, modify, and distribute this software for any
+dnl # purpose with or without fee is hereby granted, provided that the above
+dnl # copyright notice and this permission notice appear in all copies.
+dnl #
+dnl # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+dnl # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+dnl # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+dnl # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+dnl # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+dnl # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+dnl # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+
+dnl # AX_FUNC_ATTRIBUTE([FUNC-SIGNATURE], [ATTRIBUTE], [ARGS],
+dnl # [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+
+dnl # AX_FUNC_ATTRIBUTE_UNUSED([ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+
+
+AC_DEFUN([AX_FUNC_ATTRIBUTE],
+[
+AC_REQUIRE([AX_CHECK_ERROR_FLAG])
+if test x"${local_cv_prog_cc_error_flag}" != "xno"; then
+ _errflag="${local_cv_prog_cc_error_flag}"
+else
+ _errflag=""
+fi
+AC_MSG_CHECKING([if __attribute__((__$2__$3)) is supported])
+_cv_sufx_=$(echo "$3" | sed 'y|-+,=() |_p_____|')
+AC_CACHE_VAL([local_cv_prog_cc_attr_$2_${_cv_sufx}],
+[
+ AC_LANG_PUSH([C])
+ save_CFLAGS="${CFLAGS}"
+ CFLAGS="${CFLAGS} ${_errflag}"
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[
+ #ifdef HAVE_SYS_TYPES_H
+ # include <sys/types.h>
+ #endif
+ #include <stdlib.h>
+ void * attrtest($1)
+ __attribute__((__$2__$3));
+ void *
+ attrtest($1) { return(NULL); }
+ ]],
+ [[]])],
+ [eval "local_cv_prog_cc_attr_$2_${_cv_sufx_}=yes"],
+ [eval "local_cv_prog_cc_attr_$2_${_cv_sufx_}=no"])
+ CFLAGS="${save_CFLAGS}"
+ AC_LANG_POP([C])
+])
+eval "_cache_val_=\${local_cv_prog_cc_attr_$2_${_cv_sufx_}}"
+if test x"${_cache_val_}" = "xyes"; then
+ AC_MSG_RESULT([yes])
+ :
+ $4
+else
+ AC_MSG_RESULT([no])
+ :
+ $5
+fi
+])
+
+
+AC_DEFUN([AX_FUNC_ATTRIBUTE_UNUSED],
+[
+AC_REQUIRE([AX_CHECK_ERROR_FLAG])
+if test x"${local_cv_prog_cc_error_flag}" != "xno"; then
+ _errflag="${local_cv_prog_cc_error_flag}"
+else
+ _errflag=""
+fi
+AC_MSG_CHECKING([if __attribute__((unused)) is supported])
+AC_CACHE_VAL([local_cv_proc_cc_attr_unused],
+[
+ AC_LANG_PUSH([C])
+ save_CFLAGS="${CFLAGS}"
+ CFLAGS="${CFLAGS} ${_errflag}"
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[
+ void attrtest(void)
+ __attribute__((unused));
+ void
+ attrtest(void) {}
+ ]],
+ [[
+ int attrtest_var
+ __attribute__((unused));
+ ]])],
+ [local_cv_proc_cc_attr_unused=yes],
+ [local_cv_proc_cc_attr_unused=no])
+ CFLAGS="${save_CFLAGS}"
+ AC_LANG_POP([C])
+])
+if test x"${local_cv_proc_cc_attr_unused}" = "xyes"; then
+ AC_MSG_RESULT([yes])
+ :
+ $1
+else
+ AC_MSG_RESULT([no])
+ :
+ $2
+fi
+])
diff --git a/src/Makefile.am b/src/Makefile.am
index d2ffbfa..cb7ca6d 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -4,6 +4,7 @@ bin_PROGRAMS = ezstream
bin_SCRIPTS = ezstream-file.sh
noinst_HEADERS = \
+ attributes.h \
cfg.h \
configfile.h \
ezstream.h \
diff --git a/src/attr_config.h.in b/src/attr_config.h.in
new file mode 100644
index 0000000..576191d
--- /dev/null
+++ b/src/attr_config.h.in
@@ -0,0 +1,20 @@
+#ifndef __ATTR_CONFIG_H__
+#define __ATTR_CONFIG_H__
+
+#ifndef CFG_HAVE_ATTRIBUTES
+# define CFG_HAVE_ATTRIBUTES @CFG_HAVE_ATTRIBUTES@
+#endif /* !CFG_HAVE_ATTRIBUTES */
+
+#ifndef CFG_ATTRIBUTE_UNUSED
+# define CFG_ATTRIBUTE_UNUSED @CFG_ATTRIBUTE_UNUSED@
+#endif /* !CFG_ATTRIBUTE_UNUSED */
+
+#ifndef CFG_ATTRIBUTE_FORMAT
+# define CFG_ATTRIBUTE_FORMAT @CFG_ATTRIBUTE_FORMAT@
+#endif /* !CFG_ATTRIBUTE_FORMAT */
+
+#ifndef CFG_ATTRIBUTE_NONNULL
+# define CFG_ATTRIBUTE_NONNULL @CFG_ATTRIBUTE_NONNULL@
+#endif /* !CFG_ATTRIBUTE_NONNULL */
+
+#endif /* __ATTR_CONFIG_H__ */
diff --git a/src/attributes.h b/src/attributes.h
new file mode 100644
index 0000000..98ceef5
--- /dev/null
+++ b/src/attributes.h
@@ -0,0 +1,45 @@
+#ifndef __ATTRIBUTES_H__
+#define __ATTRIBUTES_H__
+
+#include "attr_config.h"
+
+#if defined(CFG_HAVE_ATTRIBUTES) && 1 == CFG_HAVE_ATTRIBUTES
+ /* nothing */
+#else
+# define __attribute__(x) \
+ /* nothing, e.g. for sys/tree.h */
+#endif /* CFG_HAVE_ATTRIBUTES */
+
+#if defined(CFG_ATTRIBUTE_UNUSED) && 1 == CFG_ATTRIBUTE_UNUSED
+# define ATTRIBUTE_UNUSED() \
+ __attribute__((unused))
+#else
+# define ATTRIBUTE_UNUSED() \
+ /* nothing */
+#endif /* CFG_ATTRIBUTE_UNUSED */
+
+#if defined(CFG_ATTRIBUTE_FORMAT) && 1 == CFG_ATTRIBUTE_FORMAT
+# define ATTRIBUTE_FORMAT(t, n, m) \
+ __attribute__((__format__(t, (n), (m))))
+#else
+# define ATTRIBUTE_FORMAT(t, n, m) \
+ /* nothing */
+#endif /* CFG_ATTRIBUTE_FORMAT */
+
+#if defined(CFG_ATTRIBUTE_NONNULL) && 1 == CFG_ATTRIBUTE_NONNULL
+# define ATTRIBUTE_NONNULL(n) \
+ __attribute__((__nonnull__(n)))
+# define ATTRIBUTE_NONNULL_2(n, m) \
+ __attribute__((__nonnull__(n, m)))
+# define ATTRIBUTE_NONNULL_3(n, m, o) \
+ __attribute__((__nonnull__(n, m, o)))
+#else
+# define ATTRIBUTE_NONNULL(n) \
+ /* nothing */
+# define ATTRIBUTE_NONNULL_2(n, m) \
+ /* nothing */
+# define ATTRIBUTE_NONNULL_3(n, m, o) \
+ /* nothing */
+#endif /* CFG_ATTRIBUTE_NONNULL */
+
+#endif /* __ATTRIBUTES_H__ */