git / moonbite-core / src/fs.cpp · raw

// Copyright (c) 2017-2019 The Bitcoin Core developers// Distributed under the MIT software license, see the accompanying// file COPYING or http://www.opensource.org/licenses/mit-license.php.#include <fs.h>#ifndef WIN32#include <cstring>#include <fcntl.h>#include <string>#include <sys/file.h>#include <sys/utsname.h>#include <unistd.h>#else#ifndef NOMINMAX#define NOMINMAX#endif#include <codecvt>#include <windows.h>#endifnamespace fsbridge {FILE *fopen(const fs::path& p, const char *mode){#ifndef WIN32    return ::fopen(p.string().c_str(), mode);#else    std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>,wchar_t> utf8_cvt;    return ::_wfopen(p.wstring().c_str(), utf8_cvt.from_bytes(mode).c_str());#endif}#ifndef WIN32static std::string GetErrorReason(){    return std::strerror(errno);}FileLock::FileLock(const fs::path& file){    fd = open(file.string().c_str(), O_RDWR);    if (fd == -1) {        reason = GetErrorReason();    }}FileLock::~FileLock(){    if (fd != -1) {        close(fd);    }}static bool IsWSL(){    struct utsname uname_data;    return uname(&uname_data) == 0 && std::string(uname_data.version).find("Microsoft") != std::string::npos;}bool FileLock::TryLock(){    if (fd == -1) {        return false;    }    // Exclusive file locking is broken on WSL using fcntl (issue #18622)    // This workaround can be removed once the bug on WSL is fixed    static const bool is_wsl = IsWSL();    if (is_wsl) {        if (flock(fd, LOCK_EX | LOCK_NB) == -1) {            reason = GetErrorReason();            return false;        }    } else {        struct flock lock;        lock.l_type = F_WRLCK;        lock.l_whence = SEEK_SET;        lock.l_start = 0;        lock.l_len = 0;        if (fcntl(fd, F_SETLK, &lock) == -1) {            reason = GetErrorReason();            return false;        }    }    return true;}#elsestatic std::string GetErrorReason() {    wchar_t* err;    FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,        nullptr, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), reinterpret_cast<WCHAR*>(&err), 0, nullptr);    std::wstring err_str(err);    LocalFree(err);    return std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>>().to_bytes(err_str);}FileLock::FileLock(const fs::path& file){    hFile = CreateFileW(file.wstring().c_str(),  GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,        nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);    if (hFile == INVALID_HANDLE_VALUE) {        reason = GetErrorReason();    }}FileLock::~FileLock(){    if (hFile != INVALID_HANDLE_VALUE) {        CloseHandle(hFile);    }}bool FileLock::TryLock(){    if (hFile == INVALID_HANDLE_VALUE) {        return false;    }    _OVERLAPPED overlapped = {0};    if (!LockFileEx(hFile, LOCKFILE_EXCLUSIVE_LOCK | LOCKFILE_FAIL_IMMEDIATELY, 0, std::numeric_limits<DWORD>::max(), std::numeric_limits<DWORD>::max(), &overlapped)) {        reason = GetErrorReason();        return false;    }    return true;}#endifstd::string get_filesystem_error_message(const fs::filesystem_error& e){#ifndef WIN32    return e.what();#else    // Convert from Multi Byte to utf-16    std::string mb_string(e.what());    int size = MultiByteToWideChar(CP_ACP, 0, mb_string.data(), mb_string.size(), nullptr, 0);    std::wstring utf16_string(size, L'\0');    MultiByteToWideChar(CP_ACP, 0, mb_string.data(), mb_string.size(), &*utf16_string.begin(), size);    // Convert from utf-16 to utf-8    return std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>, wchar_t>().to_bytes(utf16_string);#endif}#ifdef WIN32#ifdef __GLIBCXX__// reference: https://github.com/gcc-mirror/gcc/blob/gcc-7_3_0-release/libstdc%2B%2B-v3/include/std/fstream#L270static std::string openmodeToStr(std::ios_base::openmode mode){    switch (mode & ~std::ios_base::ate) {    case std::ios_base::out:    case std::ios_base::out | std::ios_base::trunc:        return "w";    case std::ios_base::out | std::ios_base::app:    case std::ios_base::app:        return "a";    case std::ios_base::in:        return "r";    case std::ios_base::in | std::ios_base::out:        return "r+";    case std::ios_base::in | std::ios_base::out | std::ios_base::trunc:        return "w+";    case std::ios_base::in | std::ios_base::out | std::ios_base::app:    case std::ios_base::in | std::ios_base::app:        return "a+";    case std::ios_base::out | std::ios_base::binary:    case std::ios_base::out | std::ios_base::trunc | std::ios_base::binary:        return "wb";    case std::ios_base::out | std::ios_base::app | std::ios_base::binary:    case std::ios_base::app | std::ios_base::binary:        return "ab";    case std::ios_base::in | std::ios_base::binary:        return "rb";    case std::ios_base::in | std::ios_base::out | std::ios_base::binary:        return "r+b";    case std::ios_base::in | std::ios_base::out | std::ios_base::trunc | std::ios_base::binary:        return "w+b";    case std::ios_base::in | std::ios_base::out | std::ios_base::app | std::ios_base::binary:    case std::ios_base::in | std::ios_base::app | std::ios_base::binary:        return "a+b";    default:        return std::string();    }}void ifstream::open(const fs::path& p, std::ios_base::openmode mode){    close();    mode |= std::ios_base::in;    m_file = fsbridge::fopen(p, openmodeToStr(mode).c_str());    if (m_file == nullptr) {        return;    }    m_filebuf = __gnu_cxx::stdio_filebuf<char>(m_file, mode);    rdbuf(&m_filebuf);    if (mode & std::ios_base::ate) {        seekg(0, std::ios_base::end);    }}void ifstream::close(){    if (m_file != nullptr) {        m_filebuf.close();        fclose(m_file);    }    m_file = nullptr;}void ofstream::open(const fs::path& p, std::ios_base::openmode mode){    close();    mode |= std::ios_base::out;    m_file = fsbridge::fopen(p, openmodeToStr(mode).c_str());    if (m_file == nullptr) {        return;    }    m_filebuf = __gnu_cxx::stdio_filebuf<char>(m_file, mode);    rdbuf(&m_filebuf);    if (mode & std::ios_base::ate) {        seekp(0, std::ios_base::end);    }}void ofstream::close(){    if (m_file != nullptr) {        m_filebuf.close();        fclose(m_file);    }    m_file = nullptr;}#else // __GLIBCXX__#if BOOST_VERSION >= 107700static_assert(sizeof(*BOOST_FILESYSTEM_C_STR(fs::path())) == sizeof(wchar_t),#elsestatic_assert(sizeof(*fs::path().BOOST_FILESYSTEM_C_STR) == sizeof(wchar_t),#endif // BOOST_VERSION >= 107700    "Warning: This build is using boost::filesystem ofstream and ifstream "    "implementations which will fail to open paths containing multibyte "    "characters. You should delete this static_assert to ignore this warning, "    "or switch to a different C++ standard library like the Microsoft C++ "    "Standard Library (where boost uses non-standard extensions to construct "    "stream objects with wide filenames), or the GNU libstdc++ library (where "    "a more complicated workaround has been implemented above).");#endif // __GLIBCXX__#endif // WIN32} // fsbridge