Kernel - Add doc for DeletePending and format few files

Author: Liryna

sys/cleanup.c

@@ -113,14 +113,23 @@ Return Value:
     DokanNotifyReportChange(RequestContext, fcb, FILE_NOTIFY_CHANGE_LAST_WRITE,
                             FILE_ACTION_MODIFIED);
   }
+  // DeleteOnClose is set during CreateFile but is only executed by the last
+  // handle on the object is closed. We transfer the marker to the Fcb and will
+  // see below if there is any outstanding open handle that will delay the
+  // deletion execution.
   if (DokanCCBFlagsIsSet(ccb, DOKAN_DELETE_ON_CLOSE)) {
+    // `DOKAN_FCB_STATE_DELETE_PENDING` will prevent the Fcb to be open. Note:
+    // Since `UncleanCount` is set on `DokanCompleteCreate` but this flag is
+    // checked during `DokanDispatchCreate`, there is still a possible race
+    // condition where an inflight create will succeed.
     DokanFCBFlagsSetBit(fcb, DOKAN_FCB_STATE_DELETE_PENDING);
     DokanCCBFlagsClearBit(ccb, DOKAN_DELETE_ON_CLOSE);
     DOKAN_LOG_FINE_IRP(RequestContext,
                        "Transfer DeleteOnClose from Ccb=%p to Fcb=%p", ccb,
                        fcb);
   }
-  // Only notify when the last handle on Fcb marked for deletion.
+  // The Fcb is marked for deletion due to DeleteOnClose or through
+  // FileDisposition, the last handle will execute the deletion.
   BOOLEAN deletePending =
       fcb->UncleanCount == 1 && DokanFCBIsPendingDeletion(fcb);
   BOOLEAN isDirectory = DokanFCBFlagsIsSet(fcb, DOKAN_FILE_DIRECTORY);

sys/dokan.h

@@ -275,7 +275,7 @@ typedef struct _DokanDiskControlBlock {
   ULONG IrpTimeout;
   ULONG SessionId;
   IO_REMOVE_LOCK RemoveLock;
-  
+
   // If true, we know the requested mount point is occupied by a dokan drive we
   // can't remove, so force the mount manager to auto-assign a different drive
   // letter.

sys/fileinfo.c

@@ -96,7 +96,7 @@ DokanDispatchQueryInformation(__in PREQUEST_CONTEXT RequestContext) {
       if (!PrepareOutputHelper(
               RequestContext->Irp, &allInfo,
               FIELD_OFFSET(FILE_ALL_INFORMATION, NameInformation.FileName),
-                          /*SetInformationOnFailure=*/FALSE)) {
+              /*SetInformationOnFailure=*/FALSE)) {
         status = STATUS_BUFFER_TOO_SMALL;
         __leave;
       }
@@ -106,7 +106,7 @@ DokanDispatchQueryInformation(__in PREQUEST_CONTEXT RequestContext) {
       PFILE_NAME_INFORMATION nameInfo;
       if (!PrepareOutputHelper(RequestContext->Irp, &nameInfo,
                                FIELD_OFFSET(FILE_NAME_INFORMATION, FileName),
-                          /*SetInformationOnFailure=*/FALSE)) {
+                               /*SetInformationOnFailure=*/FALSE)) {
         status = STATUS_BUFFER_TOO_SMALL;
         __leave;
       }
@@ -599,7 +599,6 @@ DokanDispatchSetInformation(__in PREQUEST_CONTEXT RequestContext) {
         }
 
         if (!isPagingIo) {
-
           CcFlushCache(&fcb->SectionObjectPointers, NULL, 0, NULL);
 
           DokanPagingIoLockRW(fcb);
@@ -620,7 +619,7 @@ DokanDispatchSetInformation(__in PREQUEST_CONTEXT RequestContext) {
       ASSERT(posInfo != NULL);
 
       DOKAN_LOG_FINE_IRP(RequestContext, "FilePositionInformation %lld",
-                posInfo->CurrentByteOffset.QuadPart);
+                         posInfo->CurrentByteOffset.QuadPart);
       fileObject->CurrentByteOffset = posInfo->CurrentByteOffset;
 
       status = STATUS_SUCCESS;
@@ -635,9 +634,9 @@ DokanDispatchSetInformation(__in PREQUEST_CONTEXT RequestContext) {
        */
       targetFileObject = RequestContext->IrpSp->Parameters.SetFile.FileObject;
       if (targetFileObject != NULL) {
-          DOKAN_LOG_FINE_IRP(RequestContext,
-                             "FileObject Specified so perform flush %p \"%wZ\"",
-                             targetFileObject, &(targetFileObject->FileName));
+        DOKAN_LOG_FINE_IRP(RequestContext,
+                           "FileObject Specified so perform flush %p \"%wZ\"",
+                           targetFileObject, &(targetFileObject->FileName));
         PDokanCCB targetCcb = (PDokanCCB)targetFileObject->FsContext2;
         ASSERT(targetCcb != NULL);
         PDokanFCB targetFcb = (PDokanFCB)targetCcb->Fcb;