[core] low level drive handling redesign

* Better split of physical vs logical
* Add handling of unmounted volumes by GUID
* Force large FAT32 cheat mode
* Improve user messages and fix some UI issues

src/drive.c

@@ -38,48 +38,197 @@ RUFUS_DRIVE_INFO SelectedDrive;
 extern BOOL enable_fixed_disks;
 
 /*
- * Open a drive or volume with optional write and lock access
+ * Working with drive indexes quite risky (left unchecked,inadvertently passing 0 as
- * Returns INVALID_HANDLE_VALUE (/!\ which is DIFFERENT from NULL /!\) on failure.
+ * index would return a handle to C:, which we might then proceed to unknowingly
- * This call is quite risky (left unchecked, inadvertently passing 0 as index would
+ * clear the MBR of!), so we mitigate the risk by forcing our indexes to belong to
- * return a handle to C:, which we might then proceed to unknowingly repartition!),
+ * the specific range [DRIVE_INDEX_MIN; DRIVE_INDEX_MAX].
- * so we apply the following mitigation factors:
- * - Valid indexes must belong to a specific range [DRIVE_INDEX_MIN; DRIVE_INDEX_MAX]
- * - When opening for write access, we lock the volume. If that fails, which would
- *   typically be the case on C:\ or any other drive in use, we report failure
- * - We report the full path of any drive that was successfully opened for write acces
  */
-HANDLE GetDriveHandle(DWORD DriveIndex, char* DriveLetter, BOOL bWriteAccess, BOOL bLockDrive)
+#define CheckDriveIndex(DriveIndex) do { \
+	if ((DriveIndex < DRIVE_INDEX_MIN) || (DriveIndex > DRIVE_INDEX_MAX)) { \
+		uprintf("WARNING: Bad index value. Please check the code!\n"); \
+		goto out; \
+	} \
+	DriveIndex -= DRIVE_INDEX_MIN; } while (0)
+
+/*
+ * Open a drive or volume with optional write and lock access
+ * Return INVALID_HANDLE_VALUE (/!\ which is DIFFERENT from NULL /!\) on failure.
+ */
+static HANDLE GetHandle(char* Path, BOOL bWriteAccess, BOOL bLockDrive)
 {
-	BOOL r;
 	DWORD size;
 	HANDLE hDrive = INVALID_HANDLE_VALUE;
-	STORAGE_DEVICE_NUMBER_REDEF device_number = {0};
-	UINT drive_type;
-	char drives[26*4];	/* "D:\", "E:\", etc. */
-	char *drive = drives;
-	char logical_drive[] = "\\\\.\\#:";
-	char physical_drive[24];
 
-	DriveIndex &= DRIVE_INDEX_MASK;
+	if (Path == NULL)
-	if ((DriveIndex < DRIVE_INDEX_MIN) || (DriveIndex > DRIVE_INDEX_MAX)) {
+		goto out;
-		uprintf("WARNING: Bad index value. Please check the code!\n");
+	hDrive = CreateFileA(Path, GENERIC_READ|(bWriteAccess?GENERIC_WRITE:0),
-	}
-	DriveIndex -= DRIVE_INDEX_MIN;
-
-	// If no drive letter is requested, open a physical drive
-	if (DriveLetter == NULL) {
-		safe_sprintf(physical_drive, sizeof(physical_drive), "\\\\.\\PHYSICALDRIVE%d", DriveIndex);
-		hDrive = CreateFileA(physical_drive, GENERIC_READ|(bWriteAccess?GENERIC_WRITE:0),
 		FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
 	if (hDrive == INVALID_HANDLE_VALUE) {
-			uprintf("Could not open drive %s: %s\n", physical_drive, WindowsErrorString());
+		uprintf("Could not open drive %s: %s\n", Path, WindowsErrorString());
 		goto out;
 	}
+
 	if (bWriteAccess) {
-			uprintf("Caution: Opened %s drive for write access\n", &physical_drive[4]);
+		uprintf("Caution: Opened drive %s for write access\n", Path);
+	}
+
+	if ((bLockDrive) && (!DeviceIoControl(hDrive, FSCTL_LOCK_VOLUME, NULL, 0, NULL, 0, &size, NULL))) {
+		uprintf("Could not get exclusive access to device %s: %s\n", Path, WindowsErrorString());
+		safe_closehandle(hDrive);
+		goto out;
+	}
+
+out:
+	return hDrive;
+}
+
+/* 
+ * Return the path to access the physical drive, or NULL on error.
+ * The string is allocated and must be freed (to ensure concurrent access)
+ */
+char* GetPhysicalName(DWORD DriveIndex)
+{
+	BOOL success = FALSE;
+	char physical_name[24];
+	char* r = NULL;
+
+	CheckDriveIndex(DriveIndex);
+	safe_sprintf(physical_name, sizeof(physical_name), "\\\\.\\PHYSICALDRIVE%d", DriveIndex);
+	success = TRUE;
+out:
+	return (success)?safe_strdup(physical_name):NULL;
+}
+
+/* 
+ * Return a handle to the physical drive identified by DriveIndex
+ */
+HANDLE GetPhysicalHandle(DWORD DriveIndex, BOOL bWriteAccess, BOOL bLockDrive)
+{
+	HANDLE hPhysical = INVALID_HANDLE_VALUE;
+	char* PhysicalPath = GetPhysicalName(DriveIndex);
+	hPhysical = GetHandle(PhysicalPath, bWriteAccess, bLockDrive);
+	safe_free(PhysicalPath);
+	return hPhysical;
+}
+
+// Return the first GUID volume name for the associated drive or NULL if not found
+// See http://msdn.microsoft.com/en-us/library/cc542456.aspx
+// The returned string is allocated and must be freed
+// TODO: a drive may have multiple volumes - should we handle those?
+char* GetLogicalName(DWORD DriveIndex, BOOL bKeepTrailingBackslash)
+{
+	BOOL success = FALSE;
+	char volume_name[MAX_PATH];
+	HANDLE hDrive = INVALID_HANDLE_VALUE, hVolume = INVALID_HANDLE_VALUE;
+	size_t len;
+	char path[MAX_PATH];
+	VOLUME_DISK_EXTENTS DiskExtents;
+	DWORD size;
+	UINT drive_type;
+	int i, j;
+	static const char* ignore_device[] = { "\\Device\\CdRom", "\\Device\\Floppy" };
+
+	CheckDriveIndex(DriveIndex);
+
+	for (i=0; hDrive == INVALID_HANDLE_VALUE; i++) {
+		if (i == 0) {
+			hVolume = FindFirstVolumeA(volume_name, sizeof(volume_name));
+			if (hVolume == INVALID_HANDLE_VALUE) {
+				uprintf("Could not access first GUID volume: %s\n", WindowsErrorString());
+				goto out;
 			}
 		} else {
-		*DriveLetter = ' ';
+			if (!FindNextVolumeA(hVolume, volume_name, sizeof(volume_name))) {
+				if (GetLastError() != ERROR_NO_MORE_FILES) {
+					uprintf("Could not access next GUID volume: %s\n", WindowsErrorString());
+				}
+				goto out;
+			}
+		}
+
+		// Sanity checks
+		len = safe_strlen(volume_name);
+		if ((len <= 1) || (safe_strnicmp(volume_name, "\\\\?\\", 4) != 0) || (volume_name[len-1] != '\\')) {
+			uprintf("'%s' is not a GUID volume name\n", volume_name);
+			continue;
+		}
+
+		drive_type = GetDriveTypeA(volume_name);
+		// NB: the HP utility allows drive_type == DRIVE_FIXED, which we don't allow by default
+		// Using Alt-F in Rufus does enable listing, but this mode is unsupported.
+		if ((drive_type != DRIVE_REMOVABLE) && ((!enable_fixed_disks) || (drive_type != DRIVE_FIXED)))
+			continue;
+
+		volume_name[len-1] = 0;
+
+		if (QueryDosDeviceA(&volume_name[4], path, sizeof(path)) == 0) {
+			uprintf("Failed to get device path for GUID volume '%s': %s\n", volume_name, WindowsErrorString());
+			continue;
+		}
+
+		for (j=0; (j<ARRAYSIZE(ignore_device)) &&
+			(safe_strnicmp(path, ignore_device[j], safe_strlen(ignore_device[j])) != 0); j++);
+		if (j < ARRAYSIZE(ignore_device)) {
+			uprintf("Skipping GUID volume for '%s'\n", path);
+			continue;
+		}
+
+		// If we can't have FILE_SHARE_WRITE, forget it
+		hDrive = CreateFileA(volume_name, GENERIC_READ, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
+		if (hDrive == INVALID_HANDLE_VALUE) {
+			uprintf("Could not open GUID volume '%s': %s\n", volume_name, WindowsErrorString());
+			continue;
+		}
+
+		if ((!DeviceIoControl(hDrive, IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS, NULL, 0,
+			&DiskExtents, sizeof(DiskExtents), &size, NULL)) || (size <= 0)) {
+			uprintf("Could not get Disk Extents: %s\n", WindowsErrorString());
+			safe_closehandle(hDrive);
+			continue;
+		}
+		safe_closehandle(hDrive);
+		if ((DiskExtents.NumberOfDiskExtents >= 1) && (DiskExtents.Extents[0].DiskNumber == DriveIndex)) {
+			if (bKeepTrailingBackslash)
+				volume_name[len-1] = '\\';
+			success = TRUE;
+			break;
+		}
+	}
+
+out:
+	if (hVolume != INVALID_HANDLE_VALUE)
+		FindVolumeClose(hVolume);
+	return (success)?safe_strdup(volume_name):NULL;
+}
+
+/* 
+ * Return a handle to the first logical volume on the disk identified by DriveIndex
+ */
+HANDLE GetLogicalHandle(DWORD DriveIndex, BOOL bWriteAccess, BOOL bLockDrive)
+{
+	HANDLE hLogical = INVALID_HANDLE_VALUE;
+	char* LogicalPath = GetLogicalName(DriveIndex, FALSE);
+	hLogical = GetHandle(LogicalPath, bWriteAccess, bLockDrive);
+	safe_free(LogicalPath);
+	return hLogical;
+}
+
+/*
+ * Returns the first drive letter for a volume located on the drive identified by DriveIndex
+ * TODO: should we return all the drive letters?
+ */
+char GetDriveLetter(DWORD DriveIndex)
+{
+	DWORD size;
+	BOOL r;
+	STORAGE_DEVICE_NUMBER_REDEF device_number = {0};
+	UINT drive_type;
+	HANDLE hDrive = INVALID_HANDLE_VALUE;
+	char *drive, drives[26*4];	/* "D:\", "E:\", etc. */
+	char logical_drive[] = "\\\\.\\#:";
+	char drive_letter = ' ';
+	CheckDriveIndex(DriveIndex);
+
 	size = GetLogicalDriveStringsA(sizeof(drives), drives);
 	if (size == 0) {
 		uprintf("GetLogicalDriveStrings failed: %s\n", WindowsErrorString());
@@ -90,8 +239,7 @@ HANDLE GetDriveHandle(DWORD DriveIndex, char* DriveLetter, BOOL bWriteAccess, BO
 		goto out;
 	}
 
-		hDrive = INVALID_HANDLE_VALUE;
+	for (drive = drives ;*drive; drive += safe_strlen(drive)+1) {
-		for ( ;*drive; drive += safe_strlen(drive)+1) {
 		if (!isalpha(*drive))
 			continue;
 		*drive = (char)toupper((int)*drive);
@@ -110,8 +258,7 @@ HANDLE GetDriveHandle(DWORD DriveIndex, char* DriveLetter, BOOL bWriteAccess, BO
 			continue;
 
 		safe_sprintf(logical_drive, sizeof(logical_drive), "\\\\.\\%c:", drive[0]);
-			hDrive = CreateFileA(logical_drive, GENERIC_READ|(bWriteAccess?GENERIC_WRITE:0),
+		hDrive = CreateFileA(logical_drive, GENERIC_READ, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
-				FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
 		if (hDrive == INVALID_HANDLE_VALUE) {
 			uprintf("Warning: could not open drive %c: %s\n", drive[0], WindowsErrorString());
 			continue;
@@ -119,39 +266,60 @@ HANDLE GetDriveHandle(DWORD DriveIndex, char* DriveLetter, BOOL bWriteAccess, BO
 
 		r = DeviceIoControl(hDrive, IOCTL_STORAGE_GET_DEVICE_NUMBER, NULL,
 			0, &device_number, sizeof(device_number), &size, NULL);
+		safe_closehandle(hDrive);
 		if ((!r) || (size <= 0)) {
-				uprintf("IOCTL_STORAGE_GET_DEVICE_NUMBER failed for device %s: %s\n",
+			uprintf("Could not get device number for device %s: %s\n",
 				logical_drive, WindowsErrorString());
 		} else if (device_number.DeviceNumber == DriveIndex) {
+			drive_letter = *drive;
 			break;
 		}
-			safe_closehandle(hDrive);
-		}
-		if (hDrive == INVALID_HANDLE_VALUE) {
-			goto out;
-		}
-		if (bWriteAccess) {
-			uprintf("Caution: Opened %s drive for write access\n", &logical_drive[4]);
-		}
-		*DriveLetter = *drive?*drive:' ';
-	}
-
-	if ((bLockDrive) && (!DeviceIoControl(hDrive, FSCTL_LOCK_VOLUME, NULL, 0, NULL, 0, &size, NULL))) {
-		uprintf("Could not get exclusive access to %s %s\n", logical_drive, WindowsErrorString());
-		safe_closehandle(hDrive);
-		goto out;
 	}
 
 out:
-	return hDrive;
+	return drive_letter;
+}
+
+/*
+ * Return the next unused drive letter from the system
+ */
+char GetUnusedDriveLetter(void)
+{
+	DWORD size;
+	char drive_letter, *drive, drives[26*4];	/* "D:\", "E:\", etc. */
+
+	size = GetLogicalDriveStringsA(sizeof(drives), drives);
+	if (size == 0) {
+		uprintf("GetLogicalDriveStrings failed: %s\n", WindowsErrorString());
+		goto out;
+	}
+	if (size > sizeof(drives)) {
+		uprintf("GetLogicalDriveStrings: buffer too small (required %d vs %d)\n", size, sizeof(drives));
+		goto out;
+	}
+
+	for (drive_letter = 'C'; drive_letter < 'Z'; drive_letter++) {
+		for (drive = drives ;*drive; drive += safe_strlen(drive)+1) {
+			if (!isalpha(*drive))
+				continue;
+			if (drive_letter == (char)toupper((int)*drive))
+				break;
+		}
+		if (!*drive)
+			break;
+	}
+
+out:
+	return (drive_letter>'Z')?' ':drive_letter;
 }
 
 /*
  * Return the drive letter and volume label
+ * If the drive doesn't have a volume assigned, space is returned for the letter
  */
 BOOL GetDriveLabel(DWORD DriveIndex, char* letter, char** label)
 {
-	HANDLE hDrive, hPhysical;
+	HANDLE hPhysical;
 	DWORD size;
 	char AutorunPath[] = "#:\\autorun.inf", *AutorunLabel = NULL;
 	wchar_t wDrivePath[] = L"#:\\";
@@ -160,19 +328,19 @@ BOOL GetDriveLabel(DWORD DriveIndex, char* letter, char** label)
 
 	*label = STR_NO_LABEL;
 
-	hDrive = GetDriveHandle(DriveIndex, letter, FALSE, FALSE);
+	*letter = GetDriveLetter(DriveIndex);
-	if (hDrive == INVALID_HANDLE_VALUE) {
+	if (*letter == ' ') {
-		// Assume we have a raw drive without volume assigned if enable_fixed_disk is true
+		// Drive without volume assigned
-		return enable_fixed_disks; 
+		// TODO: only with fixed?
+		return TRUE; 
 	}
-	safe_closehandle(hDrive);
 	AutorunPath[0] = *letter;
 	wDrivePath[0] = *letter;
 
 	// Try to read an extended label from autorun first. Fallback to regular label if not found.
 	// In the case of card readers with no card, users can get an annoying popup asking them
 	// to insert media. Use IOCTL_STORAGE_CHECK_VERIFY to prevent this
-	hPhysical = GetDriveHandle(DriveIndex, NULL, FALSE, FALSE);
+	hPhysical = GetPhysicalHandle(DriveIndex, FALSE, FALSE);
 	if (DeviceIoControl(hPhysical, IOCTL_STORAGE_CHECK_VERIFY, NULL, 0, NULL, 0, &size, NULL))
 		AutorunLabel = get_token_data_file("label", AutorunPath);
 	else if (GetLastError() == ERROR_NOT_READY)
@@ -196,28 +364,29 @@ BOOL GetDriveLabel(DWORD DriveIndex, char* letter, char** label)
 /*
  * Fill the drive properties (size, FS, etc)
  */
-BOOL GetDrivePartitionData(DWORD DeviceNumber, char* FileSystemName, DWORD FileSystemNameSize)
+BOOL GetDrivePartitionData(DWORD DriveIndex, char* FileSystemName, DWORD FileSystemNameSize)
 {
 	BOOL r;
-	HANDLE hDrive;
+	HANDLE hPhysical;
 	DWORD size;
 	BYTE geometry[128], layout[1024], part_type;
 	void* disk_geometry = (void*)geometry;
 	void* drive_layout = (void*)layout;
 	PDISK_GEOMETRY_EX DiskGeometry = (PDISK_GEOMETRY_EX)disk_geometry;
 	PDRIVE_LAYOUT_INFORMATION_EX DriveLayout = (PDRIVE_LAYOUT_INFORMATION_EX)drive_layout;
-	char DrivePath[] = "#:\\", tmp[256];
+	char* volume_name;
+	char tmp[256];
 	DWORD i, nb_partitions = 0;
 
-	hDrive = GetDriveHandle(DeviceNumber, NULL, FALSE, FALSE);
+	hPhysical = GetPhysicalHandle(DriveIndex, FALSE, FALSE);
-	if (hDrive == INVALID_HANDLE_VALUE)
+	if (hPhysical == INVALID_HANDLE_VALUE)
 		return FALSE;
 
-	r = DeviceIoControl(hDrive, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX, 
+	r = DeviceIoControl(hPhysical, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX, 
 			NULL, 0, geometry, sizeof(geometry), &size, NULL);
 	if (!r || size <= 0) {
-		uprintf("IOCTL_DISK_GET_DRIVE_GEOMETRY_EX failed for drive %c: %s\n", DrivePath[0], WindowsErrorString());
+		uprintf("Could not get geometry for drive #%d: %s\n", DriveIndex, WindowsErrorString());
-		safe_closehandle(hDrive);
+		safe_closehandle(hPhysical);
 		return FALSE;
 	}
 	SelectedDrive.DiskSize = DiskGeometry->DiskSize.QuadPart;
@@ -226,10 +395,10 @@ BOOL GetDrivePartitionData(DWORD DeviceNumber, char* FileSystemName, DWORD FileS
 	uprintf("Cylinders: %lld, TracksPerCylinder: %d, SectorsPerTrack: %d\n",
 		DiskGeometry->Geometry.Cylinders, DiskGeometry->Geometry.TracksPerCylinder, DiskGeometry->Geometry.SectorsPerTrack);
 
-	r = DeviceIoControl(hDrive, IOCTL_DISK_GET_DRIVE_LAYOUT_EX, 
+	r = DeviceIoControl(hPhysical, IOCTL_DISK_GET_DRIVE_LAYOUT_EX, 
 			NULL, 0, layout, sizeof(layout), &size, NULL );
 	if (!r || size <= 0) {
-		uprintf("IOCTL_DISK_GET_DRIVE_LAYOUT_EX failed for drive %c: %s\n", DrivePath[0], WindowsErrorString());
+		uprintf("Could not get layout for drive #d: %s\n", DriveIndex, WindowsErrorString());
 		return FALSE;
 	}
 
@@ -281,17 +450,23 @@ BOOL GetDrivePartitionData(DWORD DeviceNumber, char* FileSystemName, DWORD FileS
 		uprintf("Partition type: RAW\n");
 		break;
 	}
-	safe_closehandle(hDrive);
+	safe_closehandle(hPhysical);
 
 	// Populate the filesystem data
-	if (!GetVolumeInformationA(DrivePath, NULL, 0, NULL, NULL, NULL, FileSystemName, FileSystemNameSize)) {
+	volume_name = GetLogicalName(DriveIndex, TRUE);
+	if ((volume_name == NULL) || (!GetVolumeInformationA(volume_name, NULL, 0, NULL, NULL, NULL, FileSystemName, FileSystemNameSize))) {
+		uprintf("Did not get volume information for disk 0x%02x\n", DriveIndex);
 		FileSystemName[0] = 0;
 	}
+	safe_free(volume_name);
 
 	return TRUE;
 }
 
-BOOL UnmountDrive(HANDLE hDrive)
+/*
+ * Unmount of volume using the DISMOUNT_VOLUME ioctl
+ */
+BOOL UnmountVolume(HANDLE hDrive)
 {
 	DWORD size;
 
@@ -439,7 +614,7 @@ BOOL CreatePartition(HANDLE hDrive, int partition_style, int file_system, BOOL m
 	r = DeviceIoControl(hDrive, IOCTL_DISK_CREATE_DISK,
 			(BYTE*)&CreateDisk, size, NULL, 0, &size, NULL );
 	if (!r) {
-		uprintf("IOCTL_DISK_CREATE_DISK failed: %s\n", WindowsErrorString());
+		uprintf("Could not reset disk: %s\n", WindowsErrorString());
 		safe_closehandle(hDrive);
 		return FALSE;
 	}
@@ -448,7 +623,7 @@ BOOL CreatePartition(HANDLE hDrive, int partition_style, int file_system, BOOL m
 	r = DeviceIoControl(hDrive, IOCTL_DISK_SET_DRIVE_LAYOUT_EX,
 			(BYTE*)&DriveLayoutEx, size, NULL, 0, &size, NULL );
 	if (!r) {
-		uprintf("IOCTL_DISK_SET_DRIVE_LAYOUT_EX failed: %s\n", WindowsErrorString());
+		uprintf("Could not set drive layout: %s\n", WindowsErrorString());
 		safe_closehandle(hDrive);
 		return FALSE;
 	}

src/format.c

@@ -54,6 +54,7 @@ static int task_number = 0;
 /* Number of steps for each FS for FCC_STRUCTURE_PROGRESS */
 const int nb_steps[FS_MAX] = { 5, 5, 12, 10 };
 static int fs_index = 0;
+BOOL force_large_fat32 = FALSE;
 
 /*
  * FormatEx callback. Return FALSE to halt operations
@@ -274,6 +275,7 @@ static void ToValidLabel(WCHAR* name, BOOL bFAT)
  * -----
  * 1d02h
  */
+// TODO: use that for Format "classic"
 static DWORD GetVolumeID(void)
 {
 	SYSTEMTIME s;
@@ -331,7 +333,6 @@ static DWORD GetFATSizeSectors(DWORD DskSize, DWORD ReservedSecCnt, DWORD SecPer
 static BOOL FormatFAT32(DWORD DriveIndex)
 {
 	BOOL r = FALSE;
-	char DriveLetter;
 	DWORD i;
 	HANDLE hLogicalVolume;
 	DWORD cbRet;
@@ -342,7 +343,8 @@ static BOOL FormatFAT32(DWORD DriveIndex)
 	DWORD NumFATs = 2;
 	DWORD BackupBootSect = 6;
 	DWORD VolumeId = 0; // calculated before format
-	WCHAR wLabel[64], wDriveName[] = L"#:\\";
+	char* VolumeName = NULL;
+	WCHAR wLabel[64], *wVolumeName = NULL;
 	DWORD BurstSize = 128; // Zero in blocks of 64K typically
 
 	// Calculated later
@@ -365,18 +367,17 @@ static BOOL FormatFAT32(DWORD DriveIndex)
 	// Debug temp vars
 	ULONGLONG FatNeeded, ClusterCount;
 
-	PrintStatus(0, TRUE, "Formatting...");
+	PrintStatus(0, TRUE, "Formatting (Large FAT32)...");
-	uprintf("Using large FAT32 format method\n");
 	VolumeId = GetVolumeID();
 
 	// Open the drive (volume should already be locked)
-	hLogicalVolume = GetDriveHandle(DriveIndex, &DriveLetter, TRUE, FALSE);
+	hLogicalVolume = GetLogicalHandle(DriveIndex, TRUE, FALSE);
 	if (IS_ERROR(FormatStatus)) goto out;
 	if (hLogicalVolume == INVALID_HANDLE_VALUE)
 		die("Could not access logical volume\n", ERROR_OPEN_FAILED);
 
 	// Make sure we get exclusive access
-	if (!UnmountDrive(hLogicalVolume))
+	if (!UnmountVolume(hLogicalVolume))
 		return r;
 
 	// Work out drive params
@@ -526,7 +527,7 @@ static BOOL FormatFAT32(DWORD DriveIndex)
 	}
 
 	// Now we're commited - print some info first
-	uprintf("Size : %gGB %u sectors\n", (double) (piDrive.PartitionLength.QuadPart / (1000*1000*1000)), TotalSectors);
+	uprintf("Size : %s %u sectors\n", SizeToHumanReadable(piDrive.PartitionLength), TotalSectors);
 	uprintf("Cluster size %d bytes, %d Bytes Per Sector\n", SectorsPerCluster*BytesPerSect, BytesPerSect);
 	uprintf("Volume ID is %x:%x\n", VolumeId>>16, VolumeId&0xffff);
 	uprintf("%d Reserved Sectors, %d Sectors per FAT, %d FATs\n", ReservedSectCount, FatSize, NumFATs);
@@ -578,18 +579,22 @@ static BOOL FormatFAT32(DWORD DriveIndex)
 	// Set the FAT32 volume label
 	GetWindowTextW(hLabel, wLabel, ARRAYSIZE(wLabel));
 	ToValidLabel(wLabel, TRUE);
-	wDriveName[0] = DriveLetter;
 	// Handle must be closed for SetVolumeLabel to work
 	safe_closehandle(hLogicalVolume);
-
+	PrintStatus(0, TRUE, "Setting Label (This may take while)...");
-	PrintStatus(0, TRUE, "Setting Label (This can take while)...");
+	VolumeName = GetLogicalName(DriveIndex, TRUE);
-	if (!SetVolumeLabelW(wDriveName, wLabel)) {
+	wVolumeName = utf8_to_wchar(VolumeName);
+	if ((wVolumeName == NULL) || (!SetVolumeLabelW(wVolumeName, wLabel))) {
 		uprintf("Could not set label: %s\n", WindowsErrorString());
+		// Non fatal error
 	}
+
 	uprintf("Format completed.\n");
 	r = TRUE;
 
 out:
+	safe_free(VolumeName);
+	safe_free(wVolumeName);
 	safe_closehandle(hLogicalVolume);
 	safe_free(pFAT32BootSect);
 	safe_free(pFAT32FsInfo);
@@ -601,18 +606,28 @@ out:
 /*
  * Call on fmifs.dll's FormatEx() to format the drive
  */
-static BOOL FormatDrive(char DriveLetter)
+static BOOL FormatDrive(DWORD DriveIndex)
 {
 	BOOL r = FALSE;
 	PF_DECL(FormatEx);
-	WCHAR wDriveRoot[] = L"?:\\";
+	char* VolumeName = NULL;
+	WCHAR* wVolumeName = NULL;
+	char FSType[32], format_status[64];
 	WCHAR wFSType[32];
 	WCHAR wLabel[64];
 	size_t i;
 	char* locale;
 
-	wDriveRoot[0] = (WCHAR)DriveLetter;
+	GetWindowTextA(hFileSystem, FSType, ARRAYSIZE(FSType));
-	PrintStatus(0, TRUE, "Formatting...");
+	safe_sprintf(format_status, ARRAYSIZE(format_status), "Formatting (%s)...", FSType);
+	PrintStatus(0, TRUE, format_status);
+	VolumeName = GetLogicalName(DriveIndex, FALSE);
+	wVolumeName = utf8_to_wchar(VolumeName);
+	if (wVolumeName == NULL) {
+		uprintf("Could not read volume name\n");
+		goto out;
+	}
+
 	// LoadLibrary("fmifs.dll") appears to changes the locale, which can lead to
 	// problems with tolower(). Make sure we restore the locale. For more details,
 	// see http://comments.gmane.org/gmane.comp.gnu.mingw.user/39300
@@ -635,7 +650,7 @@ static BOOL FormatDrive(char DriveLetter)
 	format_percent = 0.0f;
 	task_number = 0;
 	fs_index = (int)ComboBox_GetItemData(hFileSystem, ComboBox_GetCurSel(hFileSystem));
-	pfFormatEx(wDriveRoot, SelectedDrive.Geometry.MediaType, wFSType, wLabel,
+	pfFormatEx(wVolumeName, SelectedDrive.Geometry.MediaType, wFSType, wLabel,
 		IsChecked(IDC_QUICKFORMAT), (ULONG)ComboBox_GetItemData(hClusterSize, ComboBox_GetCurSel(hClusterSize)),
 		FormatExCallback);
 	if (!IS_ERROR(FormatStatus)) {
@@ -644,6 +659,8 @@ static BOOL FormatDrive(char DriveLetter)
 	}
 
 out:
+	safe_free(VolumeName);
+	safe_free(wVolumeName);
 	return r;
 }
 
@@ -737,12 +754,14 @@ static BOOL AnalyzePBR(HANDLE hLogicalVolume)
 		} else if (entire_fat_32_fd_br_matches(&fake_fd)) {
 			uprintf("Drive has a FAT32 FreeDOS partition boot record\n");
 		} else {
-			uprintf("Drive has a unknown FAT16 or FAT32 partition boot record\n");
+			uprintf("Drive has an unknown FAT16 or FAT32 partition boot record\n");
 		}
 	}
 	return TRUE;
 }
 
+// TODO: We may have to clear a few more sectors past the MBR buffer zone
+// so that Windows relinquishes access
 static BOOL ClearMBRGPT(HANDLE hPhysicalDrive, LONGLONG DiskSize, DWORD SectorSize)
 {
 	BOOL r = FALSE;
@@ -1138,15 +1157,24 @@ DWORD WINAPI CloseFormatPromptThread(LPVOID param) {
 
 /*
  * Standalone thread for the formatting operation
+ * According to http://msdn.microsoft.com/en-us/library/windows/desktop/aa364562.aspx
+ * To change a volume file system
+ *   Open a volume.
+ *   Lock the volume.
+ *   Format the volume.
+ *   Dismount the volume.
+ *   Unlock the volume.
+ *   Close the volume handle.
  */
 DWORD WINAPI FormatThread(LPVOID param)
 {
 	int r, pt, bt, fs, dt;
-	BOOL ret, no_volume = FALSE;
+	BOOL ret;
-	DWORD num = (DWORD)(uintptr_t)param;
+	DWORD DriveIndex = (DWORD)(uintptr_t)param;
 	HANDLE hPhysicalDrive = INVALID_HANDLE_VALUE;
 	HANDLE hLogicalVolume = INVALID_HANDLE_VALUE;
 	SYSTEMTIME lt;
+	char* guid_volume = NULL;
 	char drive_name[] = "?:\\";
 	char bb_msg[512];
 	char logfile[MAX_PATH], *userdir;
@@ -1159,34 +1187,41 @@ DWORD WINAPI FormatThread(LPVOID param)
 	pt = GETPARTTYPE((int)ComboBox_GetItemData(hPartitionScheme, ComboBox_GetCurSel(hPartitionScheme)));
 	bt = GETBIOSTYPE((int)ComboBox_GetItemData(hPartitionScheme, ComboBox_GetCurSel(hPartitionScheme)));
 
-	if (num & DRIVE_INDEX_RAW_DRIVE) {
+	PrintStatus(0, TRUE, "Requesting disk access...\n");
-		no_volume = TRUE;
+	hPhysicalDrive = GetPhysicalHandle(DriveIndex, TRUE, TRUE);
-		uprintf("Using raw drive mode\n");
-	}
-
-	hPhysicalDrive = GetDriveHandle(num, NULL, TRUE, TRUE);
 	if (hPhysicalDrive == INVALID_HANDLE_VALUE) {
 		FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_OPEN_FAILED;
 		goto out;
 	}
-	// At this stage with have both a handle and a lock to the physical drive...
 
-	// ... but we can't write sectors that are part of a volume, even if we have 
+	// At this stage with have both a handle and a lock to the physical drive...
-	// access to physical, unless we have a lock (which doesn't have to be write)
+	drive_name[0] = GetDriveLetter(DriveIndex);
-	// Also, having a volume handle allows us to unmount the volume
+	if (drive_name[0] == ' ') {
-	if (!no_volume) {
+		uprintf("No drive letter was assigned...\n");
-		hLogicalVolume = GetDriveHandle(num, drive_name, FALSE, TRUE);
+		drive_name[0] =  GetUnusedDriveLetter();
+		if (drive_name[0] == ' ') {
+			uprintf("Could not find a suitable drive letter\n");
+			FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|APPERR(ERROR_CANT_ASSIGN_LETTER);
+			goto out;
+		}
+	} else if (!DeleteVolumeMountPointA(drive_name)) {
+		uprintf("Failed to delete mountpoint %s: %s\n", drive_name, WindowsErrorString());
+		// TODO: generate an error?
+	}
+	uprintf("Will use '%c': as volume mountpoint\n", drive_name[0]);
+
+	hLogicalVolume = GetLogicalHandle(DriveIndex, FALSE, TRUE);
 	if (hLogicalVolume == INVALID_HANDLE_VALUE) {
 		uprintf("Could not lock volume\n");
 		FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_OPEN_FAILED;
 		goto out;
 	}
-		UnmountDrive(hLogicalVolume);
+	UnmountVolume(hLogicalVolume);
-	}
 
+	PrintStatus(0, TRUE, "Analyzing existing boot records...\n");
 	AnalyzeMBR(hPhysicalDrive);
-	if (!no_volume)
 	AnalyzePBR(hLogicalVolume);
+	UpdateProgress(OP_ANALYZE_MBR, -1.0f);
 
 	if (IsChecked(IDC_BADBLOCKS)) {
 		do {
@@ -1249,8 +1284,17 @@ DWORD WINAPI FormatThread(LPVOID param)
 		}
 	}
 	// Close the (unmounted) volume before formatting, but keep the lock
-	if (!no_volume)
+	// According to MS this relinquishes the lock, so...
-		safe_closehandle(hLogicalVolume);
+	PrintStatus(0, TRUE, "Closing existing volume...\n");
+	if (!CloseHandle(hLogicalVolume)) {
+		uprintf("Could not close volume: %s\n", WindowsErrorString());
+		FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_ACCESS_DENIED;
+		goto out;
+	}
+	hLogicalVolume = INVALID_HANDLE_VALUE;
+
+	// TODO: check for cancel once in a while!
+	// TODO: our start button should become cancel instead of close
 
 	// Especially after destructive badblocks test, you must zero the MBR/GPT completely
 	// before repartitioning. Else, all kind of bad things can happen.
@@ -1272,28 +1316,24 @@ DWORD WINAPI FormatThread(LPVOID param)
 	// Add a small delay after partitioning to be safe
 	Sleep(200);
 
-	if (no_volume) {
-		hLogicalVolume = GetDriveHandle(num, drive_name, FALSE, TRUE);
-		if (hLogicalVolume == INVALID_HANDLE_VALUE) {
-			uprintf("Could not lock volume\n");
-			FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_OPEN_FAILED;
-			goto out;
-		}
-		UnmountDrive(hLogicalVolume);
-		safe_closehandle(hLogicalVolume);
-	}
-
-
 	// If FAT32 is requested and we have a large drive (>32 GB) use 
 	// large FAT32 format, else use MS's FormatEx.
-	ret = ((fs == FS_FAT32) && (SelectedDrive.DiskSize > LARGE_FAT32_SIZE))?
+	ret = ((fs == FS_FAT32) && ((SelectedDrive.DiskSize > LARGE_FAT32_SIZE) || (force_large_fat32)))?
-		FormatFAT32(num):FormatDrive(drive_name[0]);
+		FormatFAT32(DriveIndex):FormatDrive(DriveIndex);
 	if (!ret) {
 		// Error will be set by FormatDrive() in FormatStatus
 		uprintf("Format error: %s\n", StrError(FormatStatus));
 		goto out;
 	}
 
+	guid_volume = GetLogicalName(DriveIndex, TRUE);
+	if (guid_volume == NULL) {
+		uprintf("Could not get GUID volume name\n");
+		FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_NO_VOLUME_ID;
+		goto out;
+	}
+	uprintf("Found volume GUID %s\n", guid_volume);
+
 	if (pt == PARTITION_STYLE_MBR) {
 		PrintStatus(0, TRUE, "Writing master boot record...");
 		if (!WriteMBR(hPhysicalDrive)) {
@@ -1304,6 +1344,12 @@ DWORD WINAPI FormatThread(LPVOID param)
 		UpdateProgress(OP_FIX_MBR, -1.0f);
 	}
 
+	if (!SetVolumeMountPointA(drive_name, guid_volume)) {
+		uprintf("Could not remount %s on %s: %s\n", guid_volume, drive_name, WindowsErrorString());
+		FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|APPERR(ERROR_CANT_MOUNT_VOLUME);
+		goto out;
+	}
+
 	if (IsChecked(IDC_BOOT)) {
 		if (bt == BT_UEFI) {
 			// For once, no need to do anything - just check our sanity
@@ -1315,7 +1361,7 @@ DWORD WINAPI FormatThread(LPVOID param)
 		} else if ((dt == DT_WINME) || (dt == DT_FREEDOS) || ((dt == DT_ISO) && (fs == FS_NTFS))) {
 			// We still have a lock, which we need to modify the volume boot record 
 			// => no need to reacquire the lock...
-			hLogicalVolume = GetDriveHandle(num, drive_name, TRUE, FALSE);
+			hLogicalVolume = GetLogicalHandle(DriveIndex, TRUE, FALSE);
 			if (hLogicalVolume == INVALID_HANDLE_VALUE) {
 				uprintf("Could not re-mount volume for partition boot record access\n");
 				FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_OPEN_FAILED;
@@ -1333,7 +1379,7 @@ DWORD WINAPI FormatThread(LPVOID param)
 			safe_unlockclose(hLogicalVolume);
 		} else if ( (dt == DT_SYSLINUX) || ((dt == DT_ISO) && ((fs == FS_FAT16) || (fs == FS_FAT32))) ) {
 			PrintStatus(0, TRUE, "Installing Syslinux...");
-			if (!InstallSyslinux(num, drive_name)) {
+			if (!InstallSyslinux(DriveIndex, drive_name[0])) {
 				FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|ERROR_INSTALL_FAILURE;
 			}
 		}
@@ -1368,7 +1414,8 @@ DWORD WINAPI FormatThread(LPVOID param)
 					goto out;
 				}
 				if ((bt == BT_UEFI) && (!iso_report.has_efi) && (iso_report.has_win7_efi)) {
-					// TODO: progress
+					// TODO: better progress
+					// TODO: check ISO with EFI only
 					PrintStatus(0, TRUE, "Win7 EFI boot setup (this may take a while)...");
 					wim_image[0] = drive_name[0];
 					efi_dst[0] = drive_name[0];
@@ -1392,7 +1439,7 @@ DWORD WINAPI FormatThread(LPVOID param)
 			}
 		}
 		UpdateProgress(OP_FINALIZE, -1.0f);
-		PrintStatus(0, TRUE, "Finalizing...");
+		PrintStatus(0, TRUE, "Finalizing, please wait...");
 		if (IsChecked(IDC_SET_ICON))
 			SetAutorun(drive_name);
 		// Issue another complete remount before we exit, to ensure we're clean
@@ -1405,9 +1452,10 @@ DWORD WINAPI FormatThread(LPVOID param)
 	}
 
 out:
+	safe_free(guid_volume);
 	SendMessage(hISOProgressDlg, UM_ISO_EXIT, 0, 0);
 	safe_unlockclose(hLogicalVolume);
-	safe_unlockclose(hPhysicalDrive);
+	safe_unlockclose(hPhysicalDrive);	// This can take a while
 	PostMessage(hMainDialog, UM_FORMAT_COMPLETED, 0, 0);
 	ExitThread(0);
 }

src/rufus.c

@@ -93,6 +93,7 @@ static BOOL existing_key = FALSE;	// For LGP set/restore
 static BOOL iso_size_check = TRUE;
 static BOOL log_displayed = FALSE;
 static BOOL iso_provided = FALSE;
+extern BOOL force_large_fat32;
 static int selection_default;
 
 /*
@@ -605,7 +606,7 @@ static BOOL GetUSBDevices(DWORD devnum)
 			// We can afford a failure on this call - just replace the name
 			safe_strcpy(buffer, sizeof(buffer), generic_friendly_name);
 		}
-		uprintf("Found drive '%s'\n", buffer);
+		uprintf("Found device '%s'\n", buffer);
 
 		devint_data.cbSize = sizeof(devint_data);
 		hDrive = INVALID_HANDLE_VALUE;
@@ -617,6 +618,8 @@ static BOOL GetUSBDevices(DWORD devnum)
 			if (!SetupDiEnumDeviceInterfaces(dev_info, &dev_info_data, &_GUID_DEVINTERFACE_DISK, j, &devint_data)) {
 				if(GetLastError() != ERROR_NO_MORE_ITEMS) {
 					uprintf("SetupDiEnumDeviceInterfaces failed: %s\n", WindowsErrorString());
+				} else {
+					uprintf("Device was eliminated because it doesn't report itself as a disk\n");
 				}
 				break;
 			}
@@ -669,7 +672,6 @@ static BOOL GetUSBDevices(DWORD devnum)
 				// Drive letter ' ' is returned for drives that don't have a volume assigned yet
 				if (drive_letter == ' ') {
 					safe_sprintf(entry, sizeof(entry), "%s (Disk %d)", label, device_number.DeviceNumber);
-					device_number.DeviceNumber |= DRIVE_INDEX_RAW_DRIVE;
 				} else {
 					safe_sprintf(entry, sizeof(entry), "%s (%c:)", label, drive_letter);
 				}
@@ -722,6 +724,7 @@ static void InitProgress(void)
 	memset(slot_end, 0, sizeof(slot_end));
 	previous_end = 0.0f;
 
+	nb_slots[OP_ANALYZE_MBR] = 1;
 	nb_slots[OP_ZERO_MBR] = 1;
 	if (IsChecked(IDC_BADBLOCKS)) {
 		nb_slots[OP_BADBLOCKS] = -1;
@@ -751,7 +754,7 @@ static void InitProgress(void)
 	  || ((fs == FS_FAT32) && (SelectedDrive.DiskSize >= LARGE_FAT32_SIZE)) ) {
 		nb_slots[OP_FORMAT] = -1;
 	}
-	nb_slots[OP_FINALIZE] = ((dt == DT_ISO) && (fs == FS_NTFS))?2:1;
+	nb_slots[OP_FINALIZE] = ((dt == DT_ISO) && (fs == FS_NTFS))?3:2;
 
 	for (i=0; i<OP_MAX; i++) {
 		if (nb_slots[i] > 0) {
@@ -1015,7 +1018,6 @@ DWORD WINAPI ISOScanThread(LPVOID param)
 		safe_free(iso_path);
 		goto out;
 	}
-	// TODO: 4GB and UEFI = BAD!!!
 	uprintf("ISO label: '%s'\r\n  Size: %lld bytes\r\n  Has a >4GB file: %s\r\n  Uses EFI: %s%s\r\n  Uses Bootmgr: %s\r\n  Uses WinPE: %s%s\r\n  Uses isolinux: %s\n",
 		iso_report.label, iso_report.projected_size, iso_report.has_4GB_file?"Yes":"No", (iso_report.has_efi || iso_report.has_win7_efi)?"Yes":"No", 
 		(iso_report.has_win7_efi && (!iso_report.has_efi))?" (win7_x64)":"", iso_report.has_bootmgr?"Yes":"No",
@@ -1391,6 +1393,7 @@ static INT_PTR CALLBACK MainCallback(HWND hDlg, UINT message, WPARAM wParam, LPA
 				user_changed_label = FALSE;
 				return (INT_PTR)TRUE;
 			case DBT_DEVNODES_CHANGED:
+				// TODO: figure out what the deal is with extra events when FILE_SHARE_WRITE is not enabled
 				// If it's been more than a second since last device refresh, arm a refresh timer
 				if (GetTickCount() > LastRefresh + 1000) {
 					LastRefresh = GetTickCount();
@@ -1673,6 +1676,7 @@ static INT_PTR CALLBACK MainCallback(HWND hDlg, UINT message, WPARAM wParam, LPA
 						FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|APPERR(ERROR_CANT_START_THREAD);
 						PostMessage(hMainDialog, UM_FORMAT_COMPLETED, 0, 0);
 					}
+					PrintStatus(0, FALSE, "");
 					timer = 0;
 					safe_sprintf(szTimer, sizeof(szTimer), "00:00:00");
 					SendMessageA(GetDlgItem(hMainDialog, IDC_STATUS), SB_SETTEXTA,
@@ -1906,6 +1910,7 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	UpdateWindow(hDlg);
 
 	// Do our own event processing and process "magic" commands
+	// TODO: Cheat modes are not handled when the log is at the front - this sucks
 	while(GetMessage(&msg, NULL, 0, 0)) {
 		// The following ensures the processing of the ISO progress window messages
 		if (!IsWindow(hISOProgressDlg) || !IsDialogMessage(hISOProgressDlg, &msg)) {
@@ -1917,6 +1922,7 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 				PrintStatus2000("ISO size check", iso_size_check);
 				continue;
 			}
+			// TODO: move this option to advanced mode
 			// Alt-F => Toggle detection of fixed disks
 			// By default Rufus does not allow formatting USB fixed disk drives, such as USB HDDs
 			// This is a safety feature, to avoid someone unintentionally formatting a backup 
@@ -1927,6 +1933,12 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 				GetUSBDevices(0);
 				continue;
 			}
+			// Alt-L => Force Large FAT32 format to be used on < 32 GB drives
+			if ((msg.message == WM_SYSKEYDOWN) && (msg.wParam == 'L')) {
+				force_large_fat32 = !force_large_fat32;
+				PrintStatus2000("Force large FAT32 usage", force_large_fat32);
+				continue;
+			}
 			// Alt-D => Delete the NoDriveTypeAutorun key on exit (useful if the app crashed)
 			// This key is used to disable Windows popup messages when an USB drive is plugged in.
 			if ((msg.message == WM_SYSKEYDOWN) && (msg.wParam == 'D')) {

src/rufus.h

@@ -38,8 +38,6 @@
 #define RUFUS_BLOCKING_IO_TITLE     APPLICATION_NAME " - Flushing buffers"
 #define DRIVE_INDEX_MIN             0x00000080
 #define DRIVE_INDEX_MAX             0x000000C0
-#define DRIVE_INDEX_MASK            0x0000FFFF
-#define DRIVE_INDEX_RAW_DRIVE       0x00010000	// Additional drive properties stored in the drive index
 #define MAX_DRIVES                  (DRIVE_INDEX_MAX - DRIVE_INDEX_MIN)
 #define MAX_TOOLTIPS                32
 #define MAX_PROGRESS                (0xFFFF-1)	// leave room for 1 more for insta-progress workaround
@@ -135,6 +133,7 @@ enum timer_type {
 
 /* Action type, for progress bar breakdown */
 enum action_type {
+	OP_ANALYZE_MBR,
 	OP_BADBLOCKS,
 	OP_ZERO_MBR,
 	OP_PARTITION,
@@ -296,14 +295,19 @@ extern BOOL Question(char* title, char* format, ...);
 extern BOOL ExtractDOS(const char* path);
 extern BOOL ExtractISO(const char* src_iso, const char* dest_dir, BOOL scan);
 extern BOOL ExtractISOFile(const char* iso, const char* iso_file, const char* dest_file);
-extern BOOL InstallSyslinux(DWORD num, const char* drive_name);
+extern BOOL InstallSyslinux(DWORD drive_index, char drive_letter);
 DWORD WINAPI FormatThread(void* param);
+extern char* GetPhysicalName(DWORD DriveIndex);
+extern HANDLE GetPhysicalHandle(DWORD DriveIndex, BOOL bWriteAccess, BOOL bLockDrive);
+extern char* GetLogicalName(DWORD DriveIndex, BOOL bKeepTrailingBackslash);
+extern HANDLE GetLogicalHandle(DWORD DriveIndex, BOOL bWriteAccess, BOOL bLockDrive);
+extern char GetDriveLetter(DWORD DriveIndex);
+extern char GetUnusedDriveLetter(void);
 extern BOOL CreatePartition(HANDLE hDrive, int partition_style, int file_system, BOOL mbr_uefi_marker);
 extern const char* GetPartitionType(BYTE Type);
-extern BOOL GetDrivePartitionData(DWORD DeviceNumber, char* FileSystemName, DWORD FileSystemNameSize);
+extern BOOL GetDrivePartitionData(DWORD DriveIndex, char* FileSystemName, DWORD FileSystemNameSize);
-extern HANDLE GetDriveHandle(DWORD DriveIndex, char* DriveLetter, BOOL bWriteAccess, BOOL bLockDrive);
 extern BOOL GetDriveLabel(DWORD DriveIndex, char* letter, char** label);
-extern BOOL UnmountDrive(HANDLE hDrive);
+extern BOOL UnmountVolume(HANDLE hDrive);
 extern BOOL CreateProgress(void);
 extern BOOL SetAutorun(const char* path);
 extern char* FileDialog(BOOL save, char* path, char* filename, char* ext, char* ext_desc);
@@ -397,7 +401,9 @@ typedef struct {
 #define ERROR_ISO_SCAN                 0x1207
 #define ERROR_ISO_EXTRACT              0x1208
 #define ERROR_CANT_REMOUNT_VOLUME      0x1209
-#define ERROR_CANT_PATCH               0x1210
+#define ERROR_CANT_PATCH               0x120A
+#define ERROR_CANT_ASSIGN_LETTER       0x120B
+#define ERROR_CANT_MOUNT_VOLUME        0x120C
 
 /* More niceties */
 #ifndef MIN

src/rufus.rc

@@ -30,7 +30,7 @@ LANGUAGE LANG_ENGLISH, SUBLANG_NEUTRAL
 IDD_DIALOG DIALOGEX 12, 12, 206, 316
 STYLE DS_SETFONT | DS_MODALFRAME | DS_FIXEDSYS | DS_CENTER | WS_POPUP | WS_CAPTION | WS_SYSMENU
 EXSTYLE WS_EX_APPWINDOW
-CAPTION "Rufus v1.3.3.239"
+CAPTION "Rufus v1.3.3.240"
 FONT 8, "MS Shell Dlg", 400, 0, 0x1
 BEGIN
     DEFPUSHBUTTON   "Start",IDC_START,94,278,50,14
@@ -274,8 +274,8 @@ END
 //
 
 VS_VERSION_INFO VERSIONINFO
- FILEVERSION 1,3,3,239
+ FILEVERSION 1,3,3,240
- PRODUCTVERSION 1,3,3,239
+ PRODUCTVERSION 1,3,3,240
  FILEFLAGSMASK 0x3fL
 #ifdef _DEBUG
  FILEFLAGS 0x1L
@@ -292,13 +292,13 @@ BEGIN
         BEGIN
             VALUE "CompanyName", "Akeo Consulting (http://akeo.ie)"
             VALUE "FileDescription", "Rufus"
-            VALUE "FileVersion", "1.3.3.239"
+            VALUE "FileVersion", "1.3.3.240"
             VALUE "InternalName", "Rufus"
             VALUE "LegalCopyright", "(c) 2011-2013 Pete Batard (GPL v3)"
             VALUE "LegalTrademarks", "http://www.gnu.org/copyleft/gpl.html"
             VALUE "OriginalFilename", "rufus.exe"
             VALUE "ProductName", "Rufus"
-            VALUE "ProductVersion", "1.3.3.239"
+            VALUE "ProductVersion", "1.3.3.240"
         END
     END
     BLOCK "VarFileInfo"

src/stdio.c

@@ -269,6 +269,10 @@ const char* StrError(DWORD error_code)
 			"mountvol.exe command to make your device accessible again";
 	case ERROR_CANT_PATCH:
 		return "Unable to patch/setup files for boot";
+	case ERROR_CANT_ASSIGN_LETTER:
+		return "Unable to assign a drive letter";
+	case ERROR_CANT_MOUNT_VOLUME:
+		return "Can't mount GUID volume";
 	default:
 		uprintf("Unknown error: %08X\n", error_code);
 		SetLastError(error_code);

src/syslinux.c

@@ -66,7 +66,7 @@ int libfat_readfile(intptr_t pp, void *buf, size_t secsize,
  * Extract the ldlinux.sys and ldlinux.bss from resources,
  * then patch and install them
  */
-BOOL InstallSyslinux(DWORD num, const char* drive_name)
+BOOL InstallSyslinux(DWORD drive_index, char drive_letter)
 {
 	HANDLE f_handle = INVALID_HANDLE_VALUE;
 	HANDLE d_handle = INVALID_HANDLE_VALUE;
@@ -84,7 +84,7 @@ BOOL InstallSyslinux(DWORD num, const char* drive_name)
 	int nsectors;
 	int dt = (int)ComboBox_GetItemData(hBootType, ComboBox_GetCurSel(hBootType));
 
-	ldlinux_name[0] = drive_name[0];
+	ldlinux_name[0] = drive_letter;
 
 	/* Initialize the ADV -- this should be smarter */
 	syslinux_reset_adv(syslinux_adv);
@@ -135,7 +135,7 @@ BOOL InstallSyslinux(DWORD num, const char* drive_name)
 	}
 
 	/* Reopen the volume (we already have a lock) */
-	d_handle = GetDriveHandle(num, (char*)drive_name, TRUE, FALSE);
+	d_handle = GetLogicalHandle(drive_index, TRUE, FALSE);
 	if (d_handle == INVALID_HANDLE_VALUE) {
 		uprintf("Could open volume for syslinux operation\n");
 		goto out;