Merge commit '86cc97e55fe346502462284d2e636a2b3708163e' as 'Sources/OpenVPN3'

Sources/OpenVPN3/openvpn/common/strerror.hpp

@@ -0,0 +1,50 @@
+//    OpenVPN -- An application to securely tunnel IP networks
+//               over a single port, with support for SSL/TLS-based
+//               session authentication and key exchange,
+//               packet encryption, packet authentication, and
+//               packet compression.
+//
+//    Copyright (C) 2012-2017 OpenVPN Inc.
+//
+//    This program is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Affero General Public License Version 3
+//    as published by the Free Software Foundation.
+//
+//    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 Affero General Public License for more details.
+//
+//    You should have received a copy of the GNU Affero General Public License
+//    along with this program in the COPYING file.
+//    If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef OPENVPN_COMMON_STRERROR_H
+#define OPENVPN_COMMON_STRERROR_H
+
+#include <string.h>
+#include <string>
+
+#include <errno.h>
+
+namespace openvpn {
+  inline std::string strerror_str(const int errnum)
+  {
+    static const char unknown_err[] = "UNKNOWN_SYSTEM_ERROR";
+    char buf[128];
+
+#if defined(__GLIBC__) && (!defined(__USE_XOPEN2K) || defined(__USE_GNU))
+    // GNU
+    const char *errstr = ::strerror_r(errnum, buf, sizeof(buf));
+    if (errstr)
+      return std::string(errstr);
+#else
+    // POSIX
+    if (::strerror_r(errnum, buf, sizeof(buf)) == 0)
+      return std::string(buf);
+#endif
+    return std::string(unknown_err);
+  }
+}
+
+#endif