Initial commit

engines/ags/shared/util/file_stream.h

@@ -0,0 +1,90 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef AGS_SHARED_UTIL_FILE_STREAM_H
+#define AGS_SHARED_UTIL_FILE_STREAM_H
+
+#include "common/savefile.h"
+#include "common/stream.h"
+#include "common/std/functional.h"
+#include "ags/shared/util/data_stream.h"
+#include "ags/shared/util/file.h" // TODO: extract filestream mode constants
+
+namespace AGS3 {
+namespace AGS {
+namespace Shared {
+
+class FileStream : public DataStream {
+public:
+	struct CloseNotifyArgs {
+		String Filepath;
+		FileWorkMode WorkMode;
+	};
+
+	// Represents an open file object
+	// The constructor may raise std::runtime_error if
+	// - there is an issue opening the file (does not exist, locked, permissions, etc)
+	// - the open mode could not be determined
+	FileStream(const String &file_name, FileOpenMode open_mode, FileWorkMode work_mode,
+			   DataEndianess stream_endianess = kLittleEndian);
+	~FileStream() override;
+
+	FileWorkMode GetWorkMode() const { return _workMode; }
+
+	// Tells if there were errors during previous io operation(s);
+	// the call to GetError() *resets* the error record.
+	bool GetError() const override;
+	void Close() override;
+	bool Flush() override;
+
+	// Is stream valid (underlying data initialized properly)
+	bool IsValid() const override;
+	// Is end of stream
+	bool EOS() const override;
+	// Total length of stream (if known)
+	soff_t GetLength() const override;
+	// Current position (if known)
+	soff_t GetPosition() const override;
+	bool CanRead() const override;
+	bool CanWrite() const override;
+	bool CanSeek() const override;
+
+	size_t Read(void *buffer, size_t size) override;
+	int32_t ReadByte() override;
+	size_t Write(const void *buffer, size_t size) override;
+	int32_t WriteByte(uint8_t b) override;
+
+	soff_t Seek(soff_t offset, StreamSeek origin) override;
+
+private:
+	void Open(const String &file_name, FileOpenMode open_mode, FileWorkMode work_mode);
+	String getSaveName(const String &filename);
+	Common::OutSaveFile *openForWriting(const String &saveName, FileOpenMode open_mode, FileWorkMode work_mode);
+
+	Common::Stream *_file;
+	const FileWorkMode  _workMode;
+};
+
+} // namespace Shared
+} // namespace AGS
+} // namespace AGS3
+
+#endif