Adding upstream version 2:2.6.1.upstream/2%2.6.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 103 insertions, 0 deletions

diff --git a/lib/libcryptsetup_symver.h b/lib/libcryptsetup_symver.h
new file mode 100644
index 0000000..a5aa8f9
--- /dev/null
+++ b/lib/libcryptsetup_symver.h
@@ -0,0 +1,103 @@
+/*
+ * Helpers for defining versioned symbols
+ *
+ * Copyright (C) 2021-2023 Red Hat, Inc. All rights reserved.
+ *
+ * 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.
+ */
+
+#ifndef _LIBCRYPTSETUP_SYMVER_H
+#define _LIBCRYPTSETUP_SYMVER_H
+
+/*
+ * Note on usage:
+ *
+ * Do not use CRYPT_SYMBOL_EXPORT_NEW and CRYPT_SYMBOL_EXPORT_OLD on public
+ * symbols being exported only once. Linker will handle it automatically as
+ * always.
+ *
+ * It's supposed to be used only with symbols that are exported in at least
+ * two versions simultaneously as follows:
+ *
+ * - the latest version is marked with _NEW variant and all other compatible
+ *   symbols should be marked with _OLD variant
+ *
+ * Examples:
+ *
+ * - int crypt_func_X(unsigned *x, long y) gets introduced in CRYPTSETUP_2.4.
+ *
+ *   No need to use any macro referenced here, just add proper version
+ *   mapping in libcryptsetup.sym file.
+ *
+ *   In later version CRYPTSETUP_2.5 symbol crypt_func_X has to fixed
+ *   in incompatible way by adding new function parameter. The new version
+ *   has to be added in mapping file libcryptsetup.sym as well.
+ *
+ *   The definition of compatible function gets prefixed with following macro:
+ *
+ *   CRYPT_SYMBOL_EXPORT_OLD(int, crypt_func_X, 2, 4,
+ *   			     unsigned *x, long y)
+ *   {
+ *   	function body
+ *   }
+ *
+ *   Whereas new version introduced in CRYPTSETUP_2.5 is defined as follows:
+ *
+ *   CRYPT_SYMBOL_EXPORT_NEW(int, crypt_func_X, 2, 5,
+ *   			     unsigned *x, long y, void *new_parameter)
+ *   {
+ *   	function body
+ *   }
+ *
+ *   If in later version CRYPTSETUP_2.6 yet another version of crypt_func_X gets
+ *   introduced it will be prefixed with CRYPT_SYMBOL_EXPORT_NEW(int, crypt_func_X, 2, 6...)
+ *   macro and all previous versions CRYPTSETUP_2.4 and CRYPTSETUP_2.5 will be
+ *   under CRYPT_SYMBOL_EXPORT_OLD(int, crypt_func_X, ...) macro
+ */
+
+#if HAVE_ATTRIBUTE_SYMVER
+#  define _CRYPT_SYMVER(_local_sym, _public_sym, _ver_str, _maj, _min)     \
+     __attribute__((__symver__(#_public_sym _ver_str #_maj "." #_min)))
+#endif
+
+#if !defined(_CRYPT_SYMVER) && (defined(__GNUC__) || defined(__clang__))
+#  define _CRYPT_SYMVER(_local_sym, _public_sym, _ver_str, _maj, _min)         \
+     __asm__(".symver " #_local_sym "," #_public_sym _ver_str #_maj "." #_min);
+#endif
+
+#define _CRYPT_FUNC(_public_sym, _prefix_str, _maj, _min, _ret, ...)                                    \
+  _ret __##_public_sym##_v##_maj##_##_min(__VA_ARGS__);                                                 \
+  _CRYPT_SYMVER(__##_public_sym##_v##_maj##_##_min, _public_sym, _prefix_str "CRYPTSETUP_", _maj, _min) \
+  _ret __##_public_sym##_v##_maj##_##_min(__VA_ARGS__)
+
+#ifdef _CRYPT_SYMVER
+
+#  define CRYPT_SYMBOL_EXPORT_OLD(_ret, _public_sym, _maj, _min, ...)  \
+     _CRYPT_FUNC(_public_sym, "@", _maj, _min, _ret, __VA_ARGS__)
+#  define CRYPT_SYMBOL_EXPORT_NEW(_ret, _public_sym, _maj, _min, ...)  \
+     _CRYPT_FUNC(_public_sym, "@@", _maj, _min, _ret, __VA_ARGS__)
+
+#else /* no support for symbol versioning at all */
+
+#  define CRYPT_SYMBOL_EXPORT_OLD(_ret, _public_sym, _maj, _min, ...)  \
+     static inline __attribute__((unused))                             \
+       _ret __##_public_sym##_v##_maj##_##_min(__VA_ARGS__)
+
+#  define CRYPT_SYMBOL_EXPORT_NEW(_ret, _public_sym, _maj, _min, ...) \
+     _ret _public_sym(__VA_ARGS__)
+
+#endif
+
+#endif /* _LIBCRYPTSETUP_SYMVER_H */