[iso] reload label after formatting

* The Windows APIs may further modify the label compared to our proposed
  version (e.g. remove trailing spaces), and we need an exact label for
  the Syslinux/GRUB config file update.
* This issue was reported against Springdale Linux, where the isolinux.cfg
  label was patched using 'SPRINGDALE\x20' instead of 'SPRINGDALE'
* Closes #784
* Also ensure that we don't replace NULL buffers in msapi_utf8.h and add
  GetVolumeInformationU()

src/drive.c

@@ -486,10 +486,8 @@ BOOL GetDriveLabel(DWORD DriveIndex, char* letters, char** label)
 {
 	HANDLE hPhysical;
 	DWORD size;
-	char AutorunPath[] = "#:\\autorun.inf", *AutorunLabel = NULL;
-	wchar_t wDrivePath[] = L"#:\\";
-	wchar_t wVolumeLabel[MAX_PATH+1];
 	static char VolumeLabel[MAX_PATH + 1];
+	char DrivePath[] = "#:\\", AutorunPath[] = "#:\\autorun.inf", *AutorunLabel = NULL;
 
 	*label = STR_NO_LABEL;
 
@@ -501,7 +499,7 @@ BOOL GetDriveLabel(DWORD DriveIndex, char* letters, char** label)
 	}
 	// We only care about an autorun.inf if we have a single volume
 	AutorunPath[0] = letters[0];
-	wDrivePath[0] = letters[0];
+	DrivePath[0] = letters[0];
 
 	// 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
@@ -518,10 +516,11 @@ BOOL GetDriveLabel(DWORD DriveIndex, char* letters, char** label)
 		safe_strcpy(VolumeLabel, sizeof(VolumeLabel), AutorunLabel);
 		safe_free(AutorunLabel);
 		*label = VolumeLabel;
-	} else if (GetVolumeInformationW(wDrivePath, wVolumeLabel, ARRAYSIZE(wVolumeLabel),
+	} else if (GetVolumeInformationU(DrivePath, VolumeLabel, ARRAYSIZE(VolumeLabel),
-		NULL, NULL, NULL, NULL, 0) && *wVolumeLabel) {
+		NULL, NULL, NULL, NULL, 0) && (VolumeLabel[0] != 0)) {
-		wchar_to_utf8_no_alloc(wVolumeLabel, VolumeLabel, sizeof(VolumeLabel));
 		*label = VolumeLabel;
+	} else {
+		duprintf("Failed to read label: %s", WindowsErrorString());
 	}
 
 	return TRUE;

src/format.c

@@ -1848,6 +1848,13 @@ DWORD WINAPI FormatThread(void* param)
 	}
 	CHECK_FOR_USER_CANCEL;
 
+	// Refresh the drive label - This is needed as Windows may have altered it from
+	// the name we proposed, and we require an exact label, to patch config files.
+	if (!GetVolumeInformationU(drive_name, img_report.usb_label, ARRAYSIZE(img_report.usb_label),
+		NULL, NULL, NULL, NULL, 0)) {
+		uprintf("Warning: Failed to refresh label: %s", WindowsErrorString());
+	}
+
 	if (IsChecked(IDC_BOOT)) {
 		if (bt == BT_UEFI_NTFS) {
 			// All good

src/msapi_utf8.h

@@ -70,7 +70,7 @@ extern "C" {
 
 #define sfree(p) do {if (p != NULL) {free((void*)(p)); p = NULL;}} while(0)
 #define wconvert(p)     wchar_t* w ## p = utf8_to_wchar(p)
-#define walloc(p, size) wchar_t* w ## p = (wchar_t*)calloc(size, sizeof(wchar_t))
+#define walloc(p, size) wchar_t* w ## p = (p == NULL)?NULL:(wchar_t*)calloc(size, sizeof(wchar_t))
 #define wfree(p) sfree(w ## p)
 
 /*
@@ -107,6 +107,9 @@ static __inline wchar_t* utf8_to_wchar(const char* str)
 	int size = 0;
 	wchar_t* wstr = NULL;
 
+	if (str == NULL)
+		return NULL;
+
 	// Find out the size we need to allocate for our converted string
 	size = MultiByteToWideChar(CP_UTF8, 0, str, -1, NULL, 0);
 	if (size <= 1)	// An empty string would be size 1
@@ -867,7 +870,8 @@ static __inline int _mkdirU(const char* dirname)
 static __inline BOOL SetupDiGetDeviceRegistryPropertyU(HDEVINFO DeviceInfoSet, PSP_DEVINFO_DATA DeviceInfoData,
 	DWORD Property, PDWORD PropertyRegDataType, PBYTE PropertyBuffer, DWORD PropertyBufferSize, PDWORD RequiredSize)
 {
-	DWORD ret = FALSE, err = ERROR_INVALID_DATA;
+	BOOL ret = FALSE;
+	DWORD err = ERROR_INVALID_DATA;
 	walloc(PropertyBuffer, PropertyBufferSize);
 
 	ret = SetupDiGetDeviceRegistryPropertyW(DeviceInfoSet, DeviceInfoData, Property,
@@ -883,6 +887,37 @@ static __inline BOOL SetupDiGetDeviceRegistryPropertyU(HDEVINFO DeviceInfoSet, P
 	return ret;
 }
 
+static __inline BOOL GetVolumeInformationU(LPCSTR lpRootPathName, LPSTR lpVolumeNameBuffer,
+	DWORD nVolumeNameSize, LPDWORD lpVolumeSerialNumber, LPDWORD lpMaximumComponentLength,
+	LPDWORD lpFileSystemFlags, LPSTR lpFileSystemNameBuffer, DWORD nFileSystemNameSize)
+{
+	BOOL ret = FALSE;
+	DWORD err = ERROR_INVALID_DATA;
+	wconvert(lpRootPathName);
+	walloc(lpVolumeNameBuffer, nVolumeNameSize);
+	walloc(lpFileSystemNameBuffer, nFileSystemNameSize);
+
+	ret = GetVolumeInformationW(wlpRootPathName, wlpVolumeNameBuffer, nVolumeNameSize,
+		lpVolumeSerialNumber, lpMaximumComponentLength, lpFileSystemFlags,
+		wlpFileSystemNameBuffer, nFileSystemNameSize);
+	err = GetLastError();
+	if (ret) {
+		if ( ((lpVolumeNameBuffer != NULL) && (wchar_to_utf8_no_alloc(wlpVolumeNameBuffer,
+			lpVolumeNameBuffer, nVolumeNameSize) == 0))
+		  || ((lpFileSystemNameBuffer != NULL) && (wchar_to_utf8_no_alloc(wlpFileSystemNameBuffer,
+			lpFileSystemNameBuffer, nFileSystemNameSize) == 0)) ) {
+			err = GetLastError();
+			ret = FALSE;
+		}
+	}
+	wfree(lpVolumeNameBuffer);
+	wfree(lpFileSystemNameBuffer);
+	wfree(lpRootPathName);
+	SetLastError(err);
+	return ret;
+}
+
+
 #ifdef __cplusplus
 }
 #endif

src/rufus.rc

@@ -33,7 +33,7 @@ LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
 IDD_DIALOG DIALOGEX 12, 12, 242, 376
 STYLE DS_SETFONT | DS_MODALFRAME | DS_CENTER | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | WS_SYSMENU
 EXSTYLE WS_EX_ACCEPTFILES
-CAPTION "Rufus 2.10.962"
+CAPTION "Rufus 2.10.963"
 FONT 8, "Segoe UI Symbol", 400, 0, 0x0
 BEGIN
     LTEXT           "Device",IDS_DEVICE_TXT,9,6,200,8
@@ -320,8 +320,8 @@ END
 //
 
 VS_VERSION_INFO VERSIONINFO
- FILEVERSION 2,10,962,0
+ FILEVERSION 2,10,963,0
- PRODUCTVERSION 2,10,962,0
+ PRODUCTVERSION 2,10,963,0
  FILEFLAGSMASK 0x3fL
 #ifdef _DEBUG
  FILEFLAGS 0x1L
@@ -338,13 +338,13 @@ BEGIN
         BEGIN
             VALUE "CompanyName", "Akeo Consulting (http://akeo.ie)"
             VALUE "FileDescription", "Rufus"
-            VALUE "FileVersion", "2.10.962"
+            VALUE "FileVersion", "2.10.963"
             VALUE "InternalName", "Rufus"
             VALUE "LegalCopyright", "© 2011-2016 Pete Batard (GPL v3)"
             VALUE "LegalTrademarks", "http://www.gnu.org/copyleft/gpl.html"
             VALUE "OriginalFilename", "rufus.exe"
             VALUE "ProductName", "Rufus"
-            VALUE "ProductVersion", "2.10.962"
+            VALUE "ProductVersion", "2.10.963"
         END
     END
     BLOCK "VarFileInfo"