lokinet/llarp/util/file.cpp
2022-10-05 17:34:55 -03:00

120 lines
3.1 KiB
C++

#include "file.hpp"
#include <fstream>
#include <ios>
#include <stdexcept>
#include <llarp/util/logging.hpp>
#include <llarp/util/formattable.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 llarp::util
{
static std::streampos
slurp_file_open(const fs::path& filename, fs::ifstream& in)
{
in.exceptions(std::ifstream::failbit | std::ifstream::badbit);
in.open(filename, std::ios::binary | std::ios::in);
in.seekg(0, std::ios::end);
auto size = in.tellg();
in.seekg(0, std::ios::beg);
return size;
}
std::string
slurp_file(const fs::path& filename)
{
fs::ifstream in;
std::string contents;
auto size = slurp_file_open(filename, in);
contents.resize(size);
in.read(contents.data(), size);
return contents;
}
size_t
slurp_file(const fs::path& filename, char* buffer, size_t buffer_size)
{
fs::ifstream in;
auto size = slurp_file_open(filename, in);
if (static_cast<size_t>(size) > buffer_size)
throw std::length_error{"file is too large for buffer"};
in.read(buffer, size);
return size;
}
void
dump_file(const fs::path& filename, std::string_view contents)
{
fs::ofstream out;
out.exceptions(std::ifstream::failbit | std::ifstream::badbit);
out.open(filename, std::ios::binary | std::ios::out | std::ios::trunc);
out.write(contents.data(), static_cast<std::streamsize>(contents.size()));
}
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 llarp::util