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/*
* Copyright (C) 2008 by the Widelands Development Team
*
* 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 WL_IO_FILEWRITE_H
#define WL_IO_FILEWRITE_H
#include <cassert>
#include <cstdarg>
#include <limits>
#include <memory>
#include <string>
#include "io/streamwrite.h"
class FileSystem;
class RealFSImpl;
/// Mirror of \ref FileRead : all writes are first stored in a block of memory
/// and finally written out when write() is called.
class FileWrite : public StreamWrite {
public:
struct Pos {
Pos(size_t const p = 0) : pos(p) {
}
/// Returns a special value indicating invalidity.
static Pos null() {
return std::numeric_limits<size_t>::max();
}
bool is_null() const {
return *this == null();
}
operator size_t() const {
return pos;
}
Pos operator++() {
return ++pos;
}
Pos operator+=(Pos const other) {
return pos += other.pos;
}
private:
size_t pos;
};
struct Exception {};
struct BufferOverflow : public Exception {};
/// Set the buffer to empty.
FileWrite();
/// Clear any remaining allocated data.
~FileWrite() override;
/// Clears the object's buffer.
void clear();
/// Write the file out to disk. If successful, this clears the buffers.
/// Otherwise, an exception is thrown but the buffer remains intact (don't
/// worry, it will be cleared by the destructor).
void write(FileSystem& fs, char const* const filename);
/// Same as above, just that the data is appended to the file
/// NOTE RealFSImpl is used by purpose - zip filesystems do not support appending
void write_append(RealFSImpl& fs, char const* const filename);
/// Get the position that will be written to in the next write operation that
/// does not specify a position.
Pos get_pos() const;
/// Set the file pointer to a new location. The position can be beyond the
/// current end of file.
void set_pos(const Pos& pos);
/// Write data at the given location.
void data(const void* src, size_t size, Pos pos);
/// Write data at the current file pointer and advance it.
void data(void const* src, size_t size) override;
/// Returns the current buffer. Use this for in_memory operations.
std::string get_data() const;
private:
char* data_;
size_t length_;
size_t max_size_;
Pos filepos_;
};
#endif // end of include guard: WL_IO_FILEWRITE_H
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