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#include "stdafx.h"
#include "FileUtils.h"
#include "StringUtils.h"
#include <io.h>
#include <stdio.h>
namespace ServerRuntime
{
namespace FileUtils
{
namespace
{
static std::wstring ToWidePath(const std::string &filePath)
{
return StringUtils::Utf8ToWide(filePath);
}
}
unsigned long long GetCurrentUtcFileTime()
{
FILETIME now = {};
GetSystemTimeAsFileTime(&now);
ULARGE_INTEGER value = {};
value.LowPart = now.dwLowDateTime;
value.HighPart = now.dwHighDateTime;
return value.QuadPart;
}
bool ReadTextFile(const std::string &filePath, std::string *outText)
{
if (outText == nullptr)
{
return false;
}
outText->clear();
const std::wstring widePath = ToWidePath(filePath);
if (widePath.empty())
{
return false;
}
FILE *inFile = nullptr;
if (_wfopen_s(&inFile, widePath.c_str(), L"rb") != 0 || inFile == nullptr)
{
return false;
}
if (fseek(inFile, 0, SEEK_END) != 0)
{
fclose(inFile);
return false;
}
long fileSize = ftell(inFile);
if (fileSize < 0)
{
fclose(inFile);
return false;
}
if (fseek(inFile, 0, SEEK_SET) != 0)
{
fclose(inFile);
return false;
}
if (fileSize == 0)
{
fclose(inFile);
return true;
}
outText->resize((size_t)fileSize);
size_t bytesRead = fread(&(*outText)[0], 1, (size_t)fileSize, inFile);
fclose(inFile);
if (bytesRead != (size_t)fileSize)
{
outText->clear();
return false;
}
return true;
}
bool WriteTextFileAtomic(const std::string &filePath, const std::string &text)
{
const std::wstring widePath = ToWidePath(filePath);
if (widePath.empty())
{
return false;
}
const std::wstring tmpPath = widePath + L".tmp";
FILE *outFile = nullptr;
if (_wfopen_s(&outFile, tmpPath.c_str(), L"wb") != 0 || outFile == nullptr)
{
return false;
}
if (!text.empty())
{
size_t bytesWritten = fwrite(text.data(), 1, text.size(), outFile);
if (bytesWritten != text.size())
{
fclose(outFile);
DeleteFileW(tmpPath.c_str());
return false;
}
}
if (fflush(outFile) != 0 || _commit(_fileno(outFile)) != 0)
{
fclose(outFile);
DeleteFileW(tmpPath.c_str());
return false;
}
fclose(outFile);
DWORD attrs = GetFileAttributesW(widePath.c_str());
if (attrs != INVALID_FILE_ATTRIBUTES && ((attrs & FILE_ATTRIBUTE_DIRECTORY) == 0))
{
// Replace the destination without deleting the last known-good file first.
if (ReplaceFileW(widePath.c_str(), tmpPath.c_str(), nullptr, REPLACEFILE_IGNORE_MERGE_ERRORS, nullptr, nullptr))
{
return true;
}
}
if (MoveFileExW(tmpPath.c_str(), widePath.c_str(), MOVEFILE_REPLACE_EXISTING | MOVEFILE_WRITE_THROUGH))
{
return true;
}
// Keep the temp file on failure so the original file remains recoverable and the caller can inspect the write result.
return false;
}
}
}
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