Add fs specific errors

include/medialibrary/filesystem/Errors.h

+/*****************************************************************************
+ * Media Library
+ *****************************************************************************
+ * Copyright (C) 2015-2019 Hugo Beauzée-Luyssen, Videolabs, VideoLAN
+ *
+ * Authors: Hugo Beauzée-Luyssen <hugo@beauzee.fr>
+ *
+ * This program 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.
+ *
+ * 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 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, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#pragma once
+
+#include <stdexcept>
+#include <system_error>
+
+namespace medialibrary
+{
+
+namespace fs
+{
+
+namespace errors
+{
+
+class Exception : public std::runtime_error
+{
+public:
+    Exception( const std::string& str )
+        : std::runtime_error( str )
+    {
+    }
+};
+
+class UnknownScheme : public Exception
+{
+public:
+    UnknownScheme( const std::string& scheme )
+        : Exception( "No filesystem factory found for scheme " + scheme )
+        , m_scheme( scheme )
+    {
+    }
+
+    const std::string& scheme() const
+    {
+        return m_scheme;
+    }
+
+private:
+    std::string m_scheme;
+};
+
+class UnhandledScheme : public Exception
+{
+public:
+    UnhandledScheme( const std::string& scheme )
+        : Exception( "Unhandled MRL scheme: " + scheme )
+        , m_scheme( scheme )
+    {
+    }
+
+    const std::string& scheme() const noexcept
+    {
+        return m_scheme;
+    }
+
+private:
+    std::string m_scheme;
+};
+
+class DeviceRemoved : public Exception
+{
+public:
+    DeviceRemoved() noexcept
+        : Exception( "The device containing this file/folder was removed" )
+    {
+    }
+};
+
+class DeviceMapper : public Exception
+{
+public:
+    DeviceMapper( const std::string& str )
+        : Exception( "Failed to resolve using device mapper: " + str )
+    {
+    }
+};
+
+class DeviceListing : public Exception
+{
+public:
+    DeviceListing( const std::string& str )
+        : Exception( "Failed to list devices: " + str )
+    {
+    }
+};
+
+class NotFound : public Exception
+{
+public:
+    NotFound( const std::string& mrl, const std::string& container )
+        : Exception( mrl + " was not found in " + container )
+    {
+    }
+};
+
+class System : public Exception
+{
+public:
+#ifdef _WIN32
+    System( unsigned long err, const std::string& msg )
+        : Exception( msg +
+                     std::error_code( err, std::generic_category() ).message() )
+        , m_errc( err, std::generic_category() )
+    {
+    }
+#endif
+    System( int err, const std::string& msg )
+        : Exception( msg +
+                     std::error_code( err, std::generic_category() ).message() )
+        , m_errc( err, std::generic_category() )
+    {
+    }
+
+    const std::error_code& code() const noexcept
+    {
+        return m_errc;
+    }
+
+private:
+    std::error_code m_errc;
+};
+
+}
+
+}
+
+}