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#include <fs.h>
#ifndef WIN32
#include <fcntl.h>
#else
#include <codecvt>
#include <windows.h>
#endif
namespace fsbridge {
FILE *fopen(const fs::path& p, const char *mode)
{
return ::fopen(p.string().c_str(), mode);
}
#ifndef WIN32
static 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);
}
}
bool FileLock::TryLock()
{
if (fd == -1) {
return false;
}
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;
}
#else
static 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, 0, 0, &overlapped)) {
reason = GetErrorReason();
return false;
}
return true;
}
#endif
} // fsbridge
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