BLT/include/blt/fs/fwddecl.h

79 lines
2.3 KiB
C++

#pragma once
/*
* Copyright (C) 2024 Brett Terpstra
*
* 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 <https://www.gnu.org/licenses/>.
*/
#ifndef BLT_FS_FWDDECL_H
#define BLT_FS_FWDDECL_H
#include <stdexcept>
#include <blt/std/types.h>
namespace blt::fs
{
/**
* A simple interface which provides a way of reading the next block of data from a resource. This is designed to replace the overly complex
* std::ostream
*/
class reader_t
{
public:
virtual ~reader_t() = default;
explicit reader_t() = default;
reader_t(const reader_t&) = delete;
reader_t& operator=(const reader_t&) = delete;
/**
* Reads bytes from the internal filesystem implementation
* @param buffer buffer to copy the read bytes into
* @param bytes number of bytes to read
* @return number of bytes read, or negative value if error. Errors are not required and can just return 0
*/
virtual i64 read(char* buffer, size_t bytes) = 0;
};
/**
* A block writer without a definite backend implementation. Exactly the same as a block_reader but for writing to the filesystem.
* this is designed to replace the overly complex std::istream
*/
class writer_t
{
public:
virtual ~writer_t() = default;
explicit writer_t() = default;
writer_t(const writer_t&) = delete;
writer_t& operator=(const writer_t&) = delete;
/**
* Writes the bytes to the filesystem backend implementation
* @param buffer bytes to write
* @param bytes number of bytes to write
* @return number of bytes, or negative value if error. Zero is also a valid return, not indicating error in itself but can be the result of one.
*/
virtual i64 write(const char* buffer, size_t bytes) = 0;
/**
* Optional flush command which syncs the underlying objects
*/
virtual void flush()
{};
};
}
#endif //BLT_FS_FWDDECL_H