Implement symbol visibility.

* configure.ac: New option --enable-ld-version-script.
(GPGRT_USE_VISIBILITY): New ac_define.
(HAVE_LD_VERSION_SCRIPT): New am_conditional.
* src/gpg-error.vers: New.
* src/gpgrt-int.h: New.
* src/visibility.c, src/visibility.h: New.  Lot of changes to symbold
names.
--

This is only doe for the old API.  The estream API needs to be added.

1 files changed, 91 insertions, 0 deletions

diff --git a/src/visibility.h b/src/visibility.h
new file mode 100644
index 0000000..95d7d76
--- /dev/null
+++ b/src/visibility.h
@@ -0,0 +1,91 @@
+/* visibility.h - Set visibility attribute
+ * Copyright (C) 2014  g10 Code GmbH
+ *
+ * This file is part of libgpg-error.
+ *
+ * libgpg-error is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * libgpg-error 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _GPGRT_VISIBILITY_H
+#define _GPGRT_VISIBILITY_H
+
+/* Include the main header here so that public symbols are mapped to
+   the internal underscored ones.  */
+#ifdef _GPGRT_INCL_BY_VISIBILITY_C
+# include "gpgrt-int.h"
+#endif
+
+
+/* Our use of the ELF visibility feature works by passing
+   -fvisibiliy=hidden on the command line and by explicitly marking
+   all exported functions as visible.
+
+   NOTE: When adding new functions, please make sure to add them to
+         gpg-error.vers and gpg-error.def.in as well.  */
+
+#ifdef _GPGRT_INCL_BY_VISIBILITY_C
+
+# ifdef GPGRT_USE_VISIBILITY
+#  define MARK_VISIBLE(name) \
+     extern __typeof__ (name) name __attribute__ ((visibility("default")));
+# else
+#  define MARK_VISIBLE(name) /* */
+# endif
+
+MARK_VISIBLE (gpg_strerror)
+MARK_VISIBLE (gpg_strerror_r)
+MARK_VISIBLE (gpg_strsource)
+MARK_VISIBLE (gpg_err_code_from_errno)
+MARK_VISIBLE (gpg_err_code_to_errno)
+MARK_VISIBLE (gpg_err_code_from_syserror)
+MARK_VISIBLE (gpg_err_set_errno)
+
+MARK_VISIBLE (gpg_error_check_version)
+
+MARK_VISIBLE (gpgrt_lock_init)
+MARK_VISIBLE (gpgrt_lock_lock)
+MARK_VISIBLE (gpgrt_lock_unlock)
+MARK_VISIBLE (gpgrt_lock_destroy)
+MARK_VISIBLE (gpgrt_yield)
+
+
+
+#undef MARK_VISIBLE
+
+#else /*!_GPGRT_INCL_BY_VISIBILITY_C*/
+
+/* To avoid accidental use of the public functions inside Libgpg-error,
+   we redefine them to catch such errors.  */
+
+#define gpg_strerror                _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpg_strerror_r              _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpg_strsource               _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpg_err_code_from_errno     _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpg_err_code_to_errno       _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpg_err_code_from_syserror  _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpg_err_set_errno           _gpgrt_USE_UNDERSCORED_FUNCTION
+
+#define gpg_error_check_version     _gpgrt_USE_UNDERSCORED_FUNCTION
+
+#define gpgrt_lock_init             _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpgrt_lock_lock             _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpgrt_lock_unlock           _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpgrt_lock_destroy          _gpgrt_USE_UNDERSCORED_FUNCTION
+#define gpgrt_yield                 _gpgrt_USE_UNDERSCORED_FUNCTION
+
+
+
+#endif /*!_GPGRT_INCL_BY_VISIBILITY_C*/
+
+#endif /*_GPGRT_VISIBILITY_H*/