Windows: stop auto-mount scan on mount cancellation

Add a cancel callback and batch abort flag so auto-mount-all stops after dialog cancellation.

Mark MountVolume ERR_USER_ABORT with ERROR_CANCELLED so external /cancelmount also stops the scan.

doc/html/en/Command Line Usage for Windows.html

@@ -111,7 +111,7 @@ If it is followed by <strong>n</strong> or <strong>no</strong>: force the displa
 </tr>
 <tr>
 <td><em>/cancelmount</em></td>
-<td>Cancels any currently running mount operation and exits without displaying a status message. The process returns exit code 0 when the cancel request is accepted by the driver, or 1 otherwise.</td>
+<td>Cancels any currently running mount operation and exits without displaying a status message. The process returns exit code 0 when the cancel request is accepted by the driver, or 1 otherwise. This switch only has an effect while a mount operation is active; if an auto-mount scan is between mount attempts, the scan is not stopped by this command.</td>
 </tr>
 <tr>
 <td><em>/secureDesktop</em></td>

src/Common/Cmdline.c

@@ -67,6 +67,7 @@ BOOL CALLBACK CommandHelpDlgProc (HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM
 		}
 #if defined(TCMOUNT) && !defined(VCEXPANDER)
 		StringCchCatW (tmp, 8192, L"\nExamples:\n\nMount a volume as X:\tveracrypt.exe /q /v volume.hc /l X\nUnmount a volume X:\tveracrypt.exe /q /u X");
+		StringCchCatW (tmp, 8192, L"\n\nNote: /cancelmount requests cancellation of the currently active mount operation only. If auto-mount scanning is between mount attempts, the scan is not stopped by this command.");
 #endif
 		SetWindowTextW (GetDlgItem (hwndDlg, IDC_COMMANDHELP_TEXT), tmp);
 

src/Common/Dlgcode.c

@@ -8883,8 +8883,6 @@ static UINT g_wmWaitDlg = ::RegisterWindowMessage(L"VeraCryptWaitDlgMessage");
 #define WAIT_DLG_CANCEL_RETRY_TIMER_ID 1
 #define WAIT_DLG_CANCEL_RETRY_INTERVAL 250
 
-typedef BOOL (CALLBACK* WaitCancelProc)(void* pArg, HWND hWaitDlg);
-
 typedef struct
 {
 	HWND hwnd;
@@ -9064,7 +9062,7 @@ static LRESULT CALLBACK ShowWaitDialogParentWndProc (HWND hWnd, UINT message, WP
 }
 
 
-static void ShowWaitDialogEx(HWND hwnd, BOOL bUseHwndAsParent, WaitThreadProc callback, WaitCancelProc cancelCallback, void* pArg)
+void ShowWaitDialogEx(HWND hwnd, BOOL bUseHwndAsParent, WaitThreadProc callback, WaitCancelProc cancelCallback, void* pArg)
 {
 	BOOL bEffectiveHideWaitingDialog = bCmdHideWaitingDialogValid? bCmdHideWaitingDialog : bHideWaitingDialog;
 	WaitThreadParam threadParam;
@@ -9512,7 +9510,10 @@ retry:
 	if (mount.nReturnCode != 0)
 	{
 		if (mount.nReturnCode == ERR_USER_ABORT)
+		{
+			SetLastError (ERROR_CANCELLED);
 			return -1;
+		}
 
 		if (mount.nReturnCode == ERR_PASSWORD_WRONG)
 		{

src/Common/Dlgcode.h

@@ -767,7 +767,9 @@ INT_PTR TextEditDialogBox (BOOL readOnly, HWND parent, const WCHAR* Title, std::
 
 // Display a wait dialog while calling the provided callback with the given parameter
 typedef void (CALLBACK* WaitThreadProc)(void* pArg, HWND hWaitDlg);
+typedef BOOL (CALLBACK* WaitCancelProc)(void* pArg, HWND hWaitDlg);
 void BringToForeground(HWND hWnd);
+void ShowWaitDialogEx(HWND hwnd, BOOL bUseHwndAsParent, WaitThreadProc callback, WaitCancelProc cancelCallback, void* pArg);
 void ShowWaitDialog(HWND hwnd, BOOL bUseHwndAsParent, WaitThreadProc callback, void* pArg);
 
 // classes used to implement support for password drag-n-drop from KeePass Password Safe

src/Mount/Favorites.cpp

@@ -733,6 +733,7 @@ namespace VeraCrypt
 	{
 		FillFavoriteVolumesMenu();
 
+		::ClearFavoriteVolumeArrivalMountSuppressions ();
 		FavoritesOnArrivalMountRequired.clear();
 
 		for (const FavoriteVolume& favorite: FavoriteVolumes)

src/Mount/Mount.h

@@ -116,18 +116,9 @@ static BOOL CALLBACK DefaultMountParametersDlgProc (HWND hwndDlg, UINT msg, WPAR
 #ifdef __cplusplus
 }
 
-typedef struct
-{
-	BOOL systemFavorites;
-	BOOL logOnMount;
-	BOOL hotKeyMount;
-	/* Owned by the thread parameter when non-NULL. */
-	VeraCrypt::FavoriteVolume* favoriteVolumeToMount;
-} mountFavoriteVolumeThreadParam;
-
 void SetDriverConfigurationFlag (uint32 flag, BOOL state);
 BOOL MountFavoriteVolumes (HWND hwnd, BOOL systemFavorites = FALSE, BOOL logOnMount = FALSE, BOOL hotKeyMount = FALSE, const VeraCrypt::FavoriteVolume &favoriteVolumeToMount = VeraCrypt::FavoriteVolume());
-void __cdecl mountFavoriteVolumeThreadFunction (void *pArg);
+void ClearFavoriteVolumeArrivalMountSuppressions ();
 
 // A class that represents a device based on its device ID
 class CDevice