nf7/common/native_file_win.cc

126 lines
3.3 KiB
C++

#include "common/native_file.hh"
extern "C" {
#include <windows.h>
}
namespace nf7 {
void NativeFile::Lock() {
if (handle_) {
throw nf7::Buffer::IOException("already locked");
}
DWORD acc = 0;
if (flags_ & nf7::Buffer::kRead) {
acc |= GENERIC_READ;
}
if (flags_ & nf7::Buffer::kWrite) {
acc |= GENERIC_WRITE;
}
DWORD flags = 0;
if (nflags_ & kCreateIf) {
flags |= OPEN_ALWAYS;
} else {
flags |= OPEN_EXISTING;
}
HANDLE h = CreateFileA(
path_.string().c_str(),
acc, 0, nullptr, flags, FILE_ATTRIBUTE_NORMAL, nullptr);
if (h == INVALID_HANDLE_VALUE) {
throw IOException {"open failure"};
}
handle_ = reinterpret_cast<uintptr_t>(h);
}
void NativeFile::Unlock() {
if (!handle_) {
throw nf7::Buffer::IOException("not locked yet");
}
auto h = reinterpret_cast<HANDLE>(*handle_);
if (!CloseHandle(h)) {
throw nf7::Buffer::IOException("close failure");
}
handle_ = std::nullopt;
}
size_t NativeFile::Read(size_t offset, uint8_t* buf, size_t size) {
if (!handle_) {
throw nf7::Buffer::IOException("not locked yet");
}
const auto h = reinterpret_cast<HANDLE>(*handle_);
LONG off_low = offset & 0xFFFFFFFF;
LONG off_high = offset >> 32;
if (INVALID_SET_FILE_POINTER == SetFilePointer(h, off_low, &off_high, FILE_BEGIN)) {
throw nf7::Buffer::IOException("failed to set file pointer");
}
DWORD ret;
if (!ReadFile(h, buf, static_cast<DWORD>(size), &ret, nullptr)) {
throw nf7::Buffer::IOException("read failure");
}
return static_cast<size_t>(ret);
}
size_t NativeFile::Write(size_t offset, const uint8_t* buf, size_t size) {
if (!handle_) {
throw nf7::Buffer::IOException("not locked yet");
}
const auto h = reinterpret_cast<HANDLE>(*handle_);
LONG off_low = offset & 0xFFFFFFFF;
LONG off_high = offset >> 32;
if (INVALID_SET_FILE_POINTER == SetFilePointer(h, off_low, &off_high, FILE_BEGIN)) {
throw nf7::Buffer::IOException("failed to set file pointer");
}
DWORD ret;
if (!WriteFile(h, buf, static_cast<DWORD>(size), &ret, nullptr)) {
throw nf7::Buffer::IOException("read failure");
}
return static_cast<size_t>(ret);
}
size_t NativeFile::Truncate(size_t size) {
if (!handle_) {
throw nf7::Buffer::IOException("not locked yet");
}
const auto h = reinterpret_cast<HANDLE>(*handle_);
LONG off_low = size & 0xFFFFFFFF;
LONG off_high = size >> 32;
if (INVALID_SET_FILE_POINTER == SetFilePointer(h, off_low, &off_high, FILE_BEGIN)) {
throw nf7::Buffer::IOException("failed to set file pointer");
}
if (!SetEndOfFile(h)) {
throw nf7::Buffer::IOException("SetEndOfFile failure");
}
return size;
}
size_t NativeFile::size() const {
if (!handle_) {
throw nf7::Buffer::IOException("not locked yet");
}
const auto h = reinterpret_cast<HANDLE>(*handle_);
DWORD high;
DWORD low = GetFileSize(h, &high);
if (low == INVALID_FILE_SIZE) {
throw nf7::Buffer::IOException("GetFileSize failure");
}
return (static_cast<size_t>(high) << 32) | low;
}
void NativeFile::CleanUp() noexcept {
}
void NativeFile::Abort() noexcept {
}
size_t NativeFile::GetMemoryUsage() const noexcept {
return 0;
}
std::string NativeFile::GetDescription() const noexcept {
return path_.string() + (handle_? " (active)": " (inactive)");
}
} // namespace nf7