* By Balint Reczey <balint@balintreczey.hu>
* Copyright 2013 Balint Reczey
*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * SPDX-License-Identifier: GPL-2.0-or-later
*/
+#include "ws_compiler_tests.h"
+
/** Reset symbol export behavior.
* If you {un}define WS_BUILD_DLL on the fly you'll have to define this
* as well.
#undef WS_DLL_PUBLIC
#endif
-#ifdef WS_DLL_PUBLIC_NOEXTERN
-#undef WS_DLL_PUBLIC_NOEXTERN
+#ifdef WS_DLL_PUBLIC_DEF
+#undef WS_DLL_PUBLIC_DEF
#endif
#ifdef WS_DLL_LOCAL
#ifndef SYMBOL_EXPORT_H
#define SYMBOL_EXPORT_H
+/*
+ * NOTE: G_HAVE_GNUC_VISIBILITY is defined only if all of
+ *
+ * __attribute__ ((visibility ("hidden")))
+ *
+ * __attribute__ ((visibility ("internal")))
+ *
+ * __attribute__ ((visibility ("protected")))
+ *
+ * __attribute__ ((visibility ("default")))
+ *
+ * are supported, and at least some versions of GCC from Apple support
+ * "default" and "hidden" but not "internal" or "protected", so it
+ * shouldn't be used to determine whether "hidden" or "default" is
+ * supported.
+ *
+ * This also means that we shouldn't use G_GNUC_INTERNAL instead of
+ * WS_DLL_LOCAL, as GLib uses G_HAVE_GNUC_VISIBILITY to determine
+ * whether to use __attribute__ ((visibility ("hidden"))) for
+ * G_GNUC_INTERNAL, and that will not use it even with compilers
+ * that support it.
+ */
+
/* Originally copied from GCC Wiki at http://gcc.gnu.org/wiki/Visibility */
#if defined _WIN32 || defined __CYGWIN__
/* Compiling for Windows, so we use the Windows DLL declarations. */
#ifdef WS_BUILD_DLL
/*
- * Building a library; for all definitions, we want dllexport, and
+ * Building a DLL; for all definitions, we want dllexport, and
* (presumably so source from DLL and source from a program using the
* DLL can both include a header that declares APIs and exported data
* for the DLL), for declarations, either dllexport or dllimport will
*/
#ifdef __GNUC__
/* GCC */
-#define WS_DLL_PUBLIC __attribute__ ((dllexport)) extern
-#define WS_DLL_PUBLIC_NOEXTERN __attribute__ ((dllexport))
+ #define WS_DLL_PUBLIC_DEF __attribute__ ((dllexport))
#else /* ! __GNUC__ */
/*
* Presumably MSVC.
* Note: actually gcc seems to also support this syntax.
*/
-#define WS_DLL_PUBLIC __declspec(dllexport) extern
-#define WS_DLL_PUBLIC_NOEXTERN __declspec(dllexport)
+ #define WS_DLL_PUBLIC_DEF __declspec(dllexport)
#endif /* __GNUC__ */
#else /* WS_BUILD_DLL */
/*
*/
#ifdef __GNUC__
/* GCC */
-#define WS_DLL_PUBLIC __attribute__ ((dllimport)) extern
-#define WS_DLL_PUBLIC_NOEXTERN __attribute__ ((dllimport))
+ #define WS_DLL_PUBLIC_DEF __attribute__ ((dllimport))
#elif ! (defined ENABLE_STATIC) /* ! __GNUC__ */
/*
- * Presumably MSVC.
+ * Presumably MSVC, and we're not building all-static.
* Note: actually gcc seems to also support this syntax.
*/
-#define WS_DLL_PUBLIC __declspec(dllimport) extern
-#define WS_DLL_PUBLIC_NOEXTERN __declspec(dllimport)
+ #define WS_DLL_PUBLIC_DEF __declspec(dllimport)
#else /* ! __GNUC__ && ENABLE_STATIC */
- /* presumably MSVC */
-#define WS_DLL_PUBLIC extern
-#define WS_DLL_PUBLIC_NOEXTERN
+ /*
+ * Presumably MSVC, and we're building all-static, so we're
+ * not building any DLLs.
+ */
+ #define WS_DLL_PUBLIC_DEF
#endif /* __GNUC__ */
#endif /* WS_BUILD_DLL */
+
+ /*
+ * Symbols in a DLL are *not* exported unless they're specifically
+ * flagged as exported, so, for a non-static but non-exported
+ * symbol, we don't have to do anything.
+ */
#define WS_DLL_LOCAL
#else /* defined _WIN32 || defined __CYGWIN__ */
/*
* Compiling for UN*X, where the dllimport and dllexport stuff
* is neither necessary nor supported; just specify the
- * visibility if we have a compiler that claims compatibility
- * with GCC 4 or later.
+ * visibility if we have a compiler that supports doing so.
*/
- #if __GNUC__ >= 4
-#define WS_DLL_PUBLIC __attribute__ ((visibility ("default"))) extern
-#define WS_DLL_PUBLIC_NOEXTERN __attribute__ ((visibility ("default")))
-#define WS_DLL_LOCAL __attribute__ ((visibility ("hidden")))
- #else /* ! __GNUC__ >= 4 */
- #define WS_DLL_PUBLIC extern
- #define WS_DLL_PUBLIC_NOEXTERN
+ #if WS_IS_AT_LEAST_GNUC_VERSION(3,4) \
+ || WS_IS_AT_LEAST_XL_C_VERSION(12,0)
+ /*
+ * GCC 3.4 or later, or some compiler asserting compatibility with
+ * GCC 3.4 or later, or XL C 13.0 or later, so we have
+ * __attribute__((visibility()).
+ */
+
+ /*
+ * Symbols exported from libraries.
+ */
+ #define WS_DLL_PUBLIC_DEF __attribute__ ((visibility ("default")))
+
+ /*
+ * Non-static symbols *not* exported from libraries.
+ */
+ #define WS_DLL_LOCAL __attribute__ ((visibility ("hidden")))
+ #elif WS_IS_AT_LEAST_SUNC_VERSION(5,5)
+ /*
+ * Sun C 5.5 or later, so we have __global and __hidden.
+ * (Sun C 5.9 and later also have __attribute__((visibility()),
+ * but there's no reason to prefer it with Sun C.)
+ */
+
+ /*
+ * Symbols exported from libraries.
+ */
+ #define WS_DLL_PUBLIC_DEF __global
+
+ /*
+ * Non-static symbols *not* exported from libraries.
+ */
+ #define WS_DLL_LOCAL __hidden
+ #else
+ /*
+ * We have neither a way to make stuff not explicitly marked as
+ * visible invisible outside a library nor a way to make stuff
+ * explicitly marked as local invisible outside the library.
+ */
+
+ /*
+ * Symbols exported from libraries.
+ */
+ #define WS_DLL_PUBLIC_DEF
+
+ /*
+ * Non-static symbols *not* exported from libraries.
+ */
#define WS_DLL_LOCAL
- #endif /* __GNUC__ >= 4 */
+ #endif
#endif
+/*
+ * You *must* use this for exported data *declarations*; if you use
+ * WS_DLL_PUBLIC_DEF, some compilers, such as MSVC++, will complain
+ * about array definitions with no size.
+ *
+ * You must *not* use this for exported data *definitions*, as that
+ * will, for some compilers, cause warnings about items being initialized
+ * and declared extern.
+ *
+ * Either can be used for exported *function* declarations and definitions.
+ */
+#define WS_DLL_PUBLIC WS_DLL_PUBLIC_DEF extern
+
#endif /* SYMBOL_EXPORT_H */
+
+/*
+ * Editor modelines - http://www.wireshark.org/tools/modelines.html
+ *
+ * Local Variables:
+ * c-basic-offset: 2
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=2 tabstop=8 expandtab:
+ * :indentSize=2:tabSize=8:noTabs=true:
+ */