lokinet/llarp/util/fs.cpp
Thomas Winget 7caa87862e standardize include format and pragma once
All #ifndef guards on headers have been removed, I think,
in favor of #pragma once

Headers are now included as `#include "filename"` if the included file
resides in the same directory as the file including it, or any
subdirectory therein.  Otherwise they are included as
`#include <project/top/dir/relative/path/filename>`

The above does not include system/os headers.
2021-03-09 19:01:41 -05:00

125 lines
3.9 KiB
C++

#include "fs.hpp"
#include <llarp/util/logging/logger.hpp>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <system_error>
#ifdef WIN32
#include <io.h>
#else
#include <unistd.h>
#endif
namespace cpp17
{
namespace filesystem
{
#ifdef LOKINET_USE_CPPBACKPORT
const fs::perms active_bits(
fs::perms::all | fs::perms::set_uid | fs::perms::set_gid | fs::perms::sticky_bit);
inline mode_t
mode_cast(fs::perms prms)
{
return prms & active_bits;
}
void
permissions(const fs::path& p, fs::perms prms, std::error_code& ec)
{
std::error_code local_ec;
// OS X <10.10, iOS <8.0 and some other platforms don't support
// fchmodat(). Solaris (SunPro and gcc) only support fchmodat() on
// Solaris 11 and higher, and a runtime check is too much trouble. Linux
// does not support permissions on symbolic links and has no plans to
// support them in the future. The chmod() code is thus more practical,
// rather than always hitting ENOTSUP when sending in
// AT_SYMLINK_NO_FOLLOW.
// - See the 3rd paragraph of
// "Symbolic link ownership, permissions, and timestamps" at:
// "http://man7.org/linux/man-pages/man7/symlink.7.html"
// - See the fchmodat() Linux man page:
// "http://man7.org/linux/man-pages/man2/fchmodat.2.html"
#if defined(AT_FDCWD) && defined(AT_SYMLINK_NOFOLLOW) \
&& !(defined(__SUNPRO_CC) || defined(__sun) || defined(sun)) \
&& !(defined(linux) || defined(__linux) || defined(__linux__)) \
&& !(defined(__MAC_OS_X_VERSION_MIN_REQUIRED) && __MAC_OS_X_VERSION_MIN_REQUIRED < 101000) \
&& !(defined(__IPHONE_OS_VERSION_MIN_REQUIRED) && __IPHONE_OS_VERSION_MIN_REQUIRED < 80000) \
&& !(defined(__QNX__) && (_NTO_VERSION <= 700))
if (::fchmodat(AT_FDCWD, p.c_str(), mode_cast(prms), 0))
#else // fallback if fchmodat() not supported
if (::chmod(p.c_str(), mode_cast(prms)))
#endif
{
const int err = errno;
ec.assign(err, std::generic_category());
}
}
#endif
} // namespace filesystem
} // namespace cpp17
namespace llarp
{
namespace util
{
static std::error_code
errno_error()
{
int e = errno;
errno = 0;
return std::make_error_code(static_cast<std::errc>(e));
}
error_code_t
EnsurePrivateFile(fs::path pathname)
{
errno = 0;
error_code_t ec = errno_error();
const auto str = pathname.string();
if (fs::exists(pathname, ec)) // file exists
{
auto st = fs::status(pathname);
auto perms = st.permissions();
if ((perms & fs::perms::others_exec) != fs::perms::none)
perms = perms ^ fs::perms::others_exec;
if ((perms & fs::perms::others_write) != fs::perms::none)
perms = perms ^ fs::perms::others_write;
if ((perms & fs::perms::others_write) != fs::perms::none)
perms = perms ^ fs::perms::others_write;
if ((perms & fs::perms::group_read) != fs::perms::none)
perms = perms ^ fs::perms::group_read;
if ((perms & fs::perms::others_read) != fs::perms::none)
perms = perms ^ fs::perms::others_read;
if ((perms & fs::perms::owner_exec) != fs::perms::none)
perms = perms ^ fs::perms::owner_exec;
fs::permissions(pathname, perms, ec);
if (ec)
llarp::LogError("failed to set permissions on ", pathname);
}
else // file is not there
{
errno = 0;
int fd = ::open(str.c_str(), O_RDWR | O_CREAT, 0600);
ec = errno_error();
if (fd != -1)
{
::close(fd);
}
}
#ifndef WIN32
if (ec)
llarp::LogError("failed to ensure ", str, ", ", ec.message());
return ec;
#else
return {};
#endif
}
} // namespace util
} // namespace llarp