portapack-mayhem/firmware/application/file.hpp

336 lines
6.7 KiB
C++

/*
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
*
* This file is part of PortaPack.
*
* 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, 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; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef __FILE_H__
#define __FILE_H__
#include "ff.h"
#include "optional.hpp"
#include <cstddef>
#include <cstdint>
#include <string>
#include <array>
#include <memory>
#include <iterator>
namespace std {
namespace filesystem {
struct filesystem_error {
constexpr filesystem_error() = default;
constexpr filesystem_error(
FRESULT fatfs_error
) : err { fatfs_error }
{
}
constexpr filesystem_error(
unsigned int other_error
) : err { other_error }
{
}
uint32_t code() const {
return err;
}
std::string what() const;
private:
uint32_t err { FR_OK };
};
struct path {
using string_type = std::u16string;
using value_type = string_type::value_type;
static constexpr value_type preferred_separator = u'/';
path(
) : _s { }
{
}
path(
const path& p
) : _s { p._s }
{
}
path(
path&& p
) : _s { std::move(p._s) }
{
}
template<class Source>
path(
const Source& source
) : path { std::begin(source), std::end(source) }
{
}
template<class InputIt>
path(
InputIt first,
InputIt last
) : _s { first, last }
{
}
path(
const char16_t* const s
) : _s { s }
{
}
path(
const TCHAR* const s
) : _s { reinterpret_cast<const std::filesystem::path::value_type*>(s) }
{
}
path& operator=(const path& p) {
_s = p._s;
return *this;
}
path& operator=(path&& p) {
_s = std::move(p._s);
return *this;
}
path extension() const;
path filename() const;
path stem() const;
bool empty() const {
return _s.empty();
}
const value_type* c_str() const {
return native().c_str();
}
const string_type& native() const {
return _s;
}
std::string string() const;
path& operator+=(const path& p) {
_s += p._s;
return *this;
}
path& operator+=(const string_type& str) {
_s += str;
return *this;
}
path& replace_extension(const path& replacement = path());
private:
string_type _s;
};
bool operator<(const path& lhs, const path& rhs);
bool operator>(const path& lhs, const path& rhs);
using file_status = BYTE;
static_assert(sizeof(path::value_type) == 2, "sizeof(std::filesystem::path::value_type) != 2");
static_assert(sizeof(path::value_type) == sizeof(TCHAR), "FatFs TCHAR size != std::filesystem::path::value_type");
struct space_info {
static_assert(sizeof(std::uintmax_t) >= 8, "std::uintmax_t too small (<uint64_t)");
std::uintmax_t capacity;
std::uintmax_t free;
std::uintmax_t available;
};
struct directory_entry : public FILINFO {
file_status status() const {
return fattrib;
}
std::uintmax_t size() const {
return fsize;
};
const std::filesystem::path path() const noexcept { return { fname }; };
};
class directory_iterator {
struct Impl {
DIR dir;
directory_entry filinfo;
~Impl() {
f_closedir(&dir);
}
};
std::shared_ptr<Impl> impl { };
const path pattern { };
friend bool operator!=(const directory_iterator& lhs, const directory_iterator& rhs);
public:
using difference_type = std::ptrdiff_t;
using value_type = directory_entry;
using pointer = const directory_entry*;
using reference = const directory_entry&;
using iterator_category = std::input_iterator_tag;
directory_iterator() noexcept { };
directory_iterator(std::filesystem::path path, std::filesystem::path wild);
~directory_iterator() { }
directory_iterator& operator++();
reference operator*() const {
// TODO: Exception or assert if impl == nullptr.
return impl->filinfo;
}
};
inline const directory_iterator& begin(const directory_iterator& iter) noexcept { return iter; };
inline directory_iterator end(const directory_iterator&) noexcept { return { }; };
inline bool operator!=(const directory_iterator& lhs, const directory_iterator& rhs) { return lhs.impl != rhs.impl; };
bool is_directory(const file_status s);
bool is_regular_file(const file_status s);
space_info space(const path& p);
} /* namespace filesystem */
} /* namespace std */
std::filesystem::path next_filename_stem_matching_pattern(std::filesystem::path filename_stem_pattern);
/* Values added to FatFs FRESULT enum, values outside the FRESULT data type */
static_assert(sizeof(FIL::err) == 1, "FatFs FIL::err size not expected.");
/* Dangerous to expose these, as FatFs native error values are byte-sized. However,
* my filesystem_error implemetation is fine with it. */
#define FR_DISK_FULL (0x100)
#define FR_EOF (0x101)
#define FR_BAD_SEEK (0x102)
#define FR_UNEXPECTED (0x103)
class File {
public:
using Size = uint64_t;
using Offset = uint64_t;
using Error = std::filesystem::filesystem_error;
template<typename T>
struct Result {
enum class Type {
Success,
Error,
} type;
union {
T value_;
Error error_;
};
bool is_ok() const {
return type == Type::Success;
}
bool is_error() const {
return type == Type::Error;
}
const T& value() const {
return value_;
}
Error error() const {
return error_;
}
Result() = delete;
constexpr Result(
T value
) : type { Type::Success },
value_ { value }
{
}
constexpr Result(
Error error
) : type { Type::Error },
error_ { error }
{
}
~Result() {
if( type == Type::Success ) {
value_.~T();
}
}
};
File() { };
~File();
/* Prevent copies */
File(const File&) = delete;
File& operator=(const File&) = delete;
// TODO: Return Result<>.
Optional<Error> open(const std::filesystem::path& filename);
Optional<Error> append(const std::filesystem::path& filename);
Optional<Error> create(const std::filesystem::path& filename);
Result<Size> read(void* const data, const Size bytes_to_read);
Result<Size> write(const void* const data, const Size bytes_to_write);
Result<Offset> seek(const uint64_t Offset);
template<size_t N>
Result<Size> write(const std::array<uint8_t, N>& data) {
return write(data.data(), N);
}
Optional<Error> write_line(const std::string& s);
// TODO: Return Result<>.
Optional<Error> sync();
private:
FIL f { };
Optional<Error> open_fatfs(const std::filesystem::path& filename, BYTE mode);
};
#endif/*__FILE_H__*/