git-extra (WhoUses): auto-grow the buffer for the system information

Without this, `WhoUses.exe` can fail with a "No handle information" with a
large number of running processes.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

git-extra/sources/SystemInfo.cpp

@@ -452,15 +452,20 @@ BOOL SystemHandleInformation::Refresh()
 		(SYSTEM_HANDLE_INFORMATION*)
 		VirtualAlloc( NULL, size, MEM_COMMIT, PAGE_READWRITE );
 
+	while ( 1 ) {
 		if ( pSysHandleInformation == NULL )
 			return FALSE;
 
 		// Query the needed buffer size for the objects ( system wide )
-	if ( INtDll::NtQuerySystemInformation( 16, pSysHandleInformation,
-				size, &needed ) != 0 )
-	{
-		if ( needed == 0 )
+		DWORD result = INtDll::NtQuerySystemInformation( 16,
+				pSysHandleInformation, size, &needed );
+		if ( result == 0 )
+			break;
+
+		if ( result != STATUS_INFO_LENGTH_MISMATCH )
 		{
+			fprintf( stderr, "NtQuerySystemInformation: 0x%x\n",
+					result );
 			ret = FALSE;
 			goto cleanup;
 		}
@@ -473,17 +478,6 @@ BOOL SystemHandleInformation::Refresh()
 					MEM_COMMIT, PAGE_READWRITE );
 	}
 
-	if ( pSysHandleInformation == NULL )
-		return FALSE;
-
-	// Query the objects ( system wide )
-	if ( INtDll::NtQuerySystemInformation( 16, pSysHandleInformation,
-				size, NULL ) != 0 )
-	{
-		ret = FALSE;
-		goto cleanup;
-	}
-
 	// Iterating through the objects
 	for ( i = 0; i < pSysHandleInformation->Count; i++ )
 	{