dash/src/fs.h
Wladimir J. van der Laan fc6f390b5f Merge #17654: Unbreak build with Boost 1.72.0
a64e97dd476bda7c7981979d045b0d06d6f7ce47 wallet: unbreak with boost 1.72 (Jan Beich)

Pull request description:

  Regressed by https://github.com/boostorg/filesystem/commit/9a14c37d6f95. See [error log](http://package22.nyi.freebsd.org/data/113amd64-default-PR241449/2019-11-27_11h48m22s/logs/bitcoin-0.19.0.1.log).
  35eda631ed/src/fs.h (L14)

ACKs for top commit:
  MarcoFalke:
    ACK a64e97dd476bda7c7981979d045b0d06d6f7ce47

Tree-SHA512: 0aad2b8ec211bb81021a2f8cd2059364f949be716ebaf154dd97d5c2f7119f42553892e90e6c375018ff2155b996690c7520374762259778de88014cb531ad3b
2021-07-15 11:07:35 -05:00

96 lines
3.2 KiB
C++

// Copyright (c) 2017 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_FS_H
#define BITCOIN_FS_H
#include <stdio.h>
#include <string>
#if defined WIN32 && defined __GLIBCXX__
#include <ext/stdio_filebuf.h>
#endif
#include <boost/filesystem.hpp>
#include <boost/filesystem/fstream.hpp>
/** Filesystem operations and types */
namespace fs = boost::filesystem;
/** Bridge operations to C stdio */
namespace fsbridge {
FILE *fopen(const fs::path& p, const char *mode);
class FileLock
{
public:
FileLock() = delete;
FileLock(const FileLock&) = delete;
FileLock(FileLock&&) = delete;
explicit FileLock(const fs::path& file);
~FileLock();
bool TryLock();
std::string GetReason() { return reason; }
private:
std::string reason;
#ifndef WIN32
int fd = -1;
#else
void* hFile = (void*)-1; // INVALID_HANDLE_VALUE
#endif
};
std::string get_filesystem_error_message(const fs::filesystem_error& e);
// GNU libstdc++ specific workaround for opening UTF-8 paths on Windows.
//
// On Windows, it is only possible to reliably access multibyte file paths through
// `wchar_t` APIs, not `char` APIs. But because the C++ standard doesn't
// require ifstream/ofstream `wchar_t` constructors, and the GNU library doesn't
// provide them (in contrast to the Microsoft C++ library, see
// https://stackoverflow.com/questions/821873/how-to-open-an-stdfstream-ofstream-or-ifstream-with-a-unicode-filename/822032#822032),
// Boost is forced to fall back to `char` constructors which may not work properly.
//
// Work around this issue by creating stream objects with `_wfopen` in
// combination with `__gnu_cxx::stdio_filebuf`. This workaround can be removed
// with an upgrade to C++17, where streams can be constructed directly from
// `std::filesystem::path` objects.
#if defined WIN32 && defined __GLIBCXX__
class ifstream : public std::istream
{
public:
ifstream() = default;
explicit ifstream(const fs::path& p, std::ios_base::openmode mode = std::ios_base::in) { open(p, mode); }
~ifstream() { close(); }
void open(const fs::path& p, std::ios_base::openmode mode = std::ios_base::in);
bool is_open() { return m_filebuf.is_open(); }
void close();
private:
__gnu_cxx::stdio_filebuf<char> m_filebuf;
FILE* m_file = nullptr;
};
class ofstream : public std::ostream
{
public:
ofstream() = default;
explicit ofstream(const fs::path& p, std::ios_base::openmode mode = std::ios_base::out) { open(p, mode); }
~ofstream() { close(); }
void open(const fs::path& p, std::ios_base::openmode mode = std::ios_base::out);
bool is_open() { return m_filebuf.is_open(); }
void close();
private:
__gnu_cxx::stdio_filebuf<char> m_filebuf;
FILE* m_file = nullptr;
};
#else // !(WIN32 && __GLIBCXX__)
typedef fs::ifstream ifstream;
typedef fs::ofstream ofstream;
#endif // WIN32 && __GLIBCXX__
};
#endif // BITCOIN_FS_H