Windows-classic-samples/Samples/Hyper-V/Storage/cpp/GetStorageDependencyInformation.cpp
2025-11-28 00:35:46 +09:00

186 lines
4.2 KiB
C++

// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//
// Copyright (c) Microsoft Corporation. All rights reserved
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <virtdisk.h>
#include "Storage.h"
//
// This sample demonstrates how query storage dependency information.
//
DWORD
SampleGetStorageDependencyInformation(
_In_ LPCWSTR Disk)
{
PSTORAGE_DEPENDENCY_INFO pInfo;
DWORD infoSize;
DWORD cbSize;
HANDLE driveHandle;
GET_STORAGE_DEPENDENCY_FLAG flags;
BOOL isDisk;
DWORD opStatus;
DWORD entry;
TCHAR szVolume[8] = L"\\\\.\\C:\\";
TCHAR szDisk[19] = L"\\\\.\\PhysicalDrive0";
if (Disk[0] >= L'0' && Disk[0] <= L'9')
{
//
// Assume the user is specifying a disk between 0 and 9
//
isDisk = TRUE;
szDisk[17] = Disk[0];
flags = GET_STORAGE_DEPENDENCY_FLAG_PARENTS | GET_STORAGE_DEPENDENCY_FLAG_DISK_HANDLE;
}
else
{
//
// Assume the user is specifying a drive letter between A: and Z:
//
isDisk = FALSE;
szVolume[4] = Disk[0];
flags = GET_STORAGE_DEPENDENCY_FLAG_PARENTS;
}
driveHandle = INVALID_HANDLE_VALUE;
pInfo = NULL;
//
// Allocate enough memory for most basic case.
//
infoSize = sizeof(STORAGE_DEPENDENCY_INFO);
pInfo = (PSTORAGE_DEPENDENCY_INFO)malloc(infoSize);
if (pInfo == NULL)
{
opStatus = ERROR_NOT_ENOUGH_MEMORY;
goto Cleanup;
}
memset(pInfo, 0, infoSize);
//
// Open the drive
//
driveHandle = CreateFile(
(isDisk ? szDisk : szVolume),
GENERIC_READ,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_BACKUP_SEMANTICS,
NULL);
if (driveHandle == INVALID_HANDLE_VALUE)
{
opStatus = GetLastError();
goto Cleanup;
}
//
// Deteremine the size actually required.
//
pInfo->Version = STORAGE_DEPENDENCY_INFO_VERSION_2;
cbSize = 0;
opStatus = GetStorageDependencyInformation(
driveHandle,
flags,
infoSize,
pInfo,
&cbSize);
if (opStatus == ERROR_INSUFFICIENT_BUFFER)
{
//
// Allocate a large enough buffer.
//
free(pInfo);
infoSize = cbSize;
pInfo = (PSTORAGE_DEPENDENCY_INFO)malloc(infoSize);
if (pInfo == NULL)
{
opStatus = ERROR_NOT_ENOUGH_MEMORY;
goto Cleanup;
}
memset(pInfo, 0, infoSize);
//
// Retry with large enough buffer.
//
pInfo->Version = STORAGE_DEPENDENCY_INFO_VERSION_2;
cbSize = 0;
opStatus = GetStorageDependencyInformation(
driveHandle,
GET_STORAGE_DEPENDENCY_FLAG_PARENTS,
infoSize,
pInfo,
&cbSize);
}
if (opStatus != ERROR_SUCCESS)
{
//
// This is most likely due to the disk not being a mounted VHD.
//
goto Cleanup;
}
//
// Display the relationship between the specified volume and the underlying disks.
//
for (entry = 0; entry < pInfo->NumberEntries; entry++)
{
wprintf(L"%u:\n", entry);
wprintf(L" %u\n", pInfo->Version2Entries[entry].AncestorLevel);
wprintf(L" %s\n", pInfo->Version2Entries[entry].DependencyDeviceName);
wprintf(L" %s\n", pInfo->Version2Entries[entry].HostVolumeName);
wprintf(L" %s\n", pInfo->Version2Entries[entry].DependentVolumeName);
wprintf(L" %s\n", pInfo->Version2Entries[entry].DependentVolumeRelativePath);
}
Cleanup:
if (opStatus == ERROR_SUCCESS)
{
wprintf(L"success\n");
}
else
{
wprintf(L"error = %u\n", opStatus);
}
if (driveHandle != INVALID_HANDLE_VALUE)
{
CloseHandle(driveHandle);
}
if (pInfo != NULL)
{
free(pInfo);
}
return opStatus;
}