diff options
| author | bbahnsen <bbahnsen@6f19259b-4bc3-4df7-8a09-765794883524> | 2006-04-21 22:54:32 +0000 |
|---|---|---|
| committer | bbahnsen <bbahnsen@6f19259b-4bc3-4df7-8a09-765794883524> | 2006-04-21 22:54:32 +0000 |
| commit | 878ddf1fc3540a715f63594ed22b6929e881afb4 (patch) | |
| tree | c56c44dac138137b510e1fba7c3efe5e4d84bea2 /MdePkg/Library/BaseLib/LinkedList.c | |
| download | edk2-platforms-878ddf1fc3540a715f63594ed22b6929e881afb4.tar.xz | |
Initial import.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@3 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'MdePkg/Library/BaseLib/LinkedList.c')
| -rw-r--r-- | MdePkg/Library/BaseLib/LinkedList.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/LinkedList.c b/MdePkg/Library/BaseLib/LinkedList.c new file mode 100644 index 0000000000..0f42749775 --- /dev/null +++ b/MdePkg/Library/BaseLib/LinkedList.c @@ -0,0 +1,433 @@ +/** @file
+ Linked List Library Functions.
+
+ Copyright (c) 2006, Intel Corporation<BR>
+ All rights reserved. This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+ Module Name: LinkedList.c
+
+**/
+
+BOOLEAN
+EFIAPI
+IsNodeInList (
+ IN CONST LIST_ENTRY *List,
+ IN CONST LIST_ENTRY *Node
+ )
+{
+ UINTN Count;
+ CONST LIST_ENTRY *Ptr;
+ BOOLEAN Found;
+
+ //
+ // Test the validity of List and Node
+ //
+ ASSERT (List != NULL);
+ ASSERT (List->ForwardLink != NULL);
+ ASSERT (List->BackLink != NULL);
+ ASSERT (Node != NULL);
+
+ Count = FixedPcdGet32 (PcdMaximumLinkedListLength);
+ Ptr = List;
+ do {
+ Ptr = Ptr->ForwardLink;
+ Count--;
+ } while ((Ptr != List) && (Ptr != Node) && (Count > 0));
+ Found = (BOOLEAN)(Ptr == Node);
+
+ if (FixedPcdGet32 (PcdMaximumLinkedListLength) > 0) {
+ while ((Count > 0) && (Ptr != List)) {
+ Ptr = Ptr->ForwardLink;
+ }
+ ASSERT (Count > 0);
+ }
+
+ return Found;
+}
+
+/**
+ Initializes the head node of a doubly linked list, and returns the pointer to
+ the head node of the doubly linked list.
+
+ Initializes the forward and backward links of a new linked list. After
+ initializing a linked list with this function, the other linked list
+ functions may be used to add and remove nodes from the linked list. It is up
+ to the caller of this function to allocate the memory for ListHead.
+
+ If ListHead is NULL, then ASSERT().
+
+ @param ListHead A pointer to the head node of a new doubly linked list.
+
+ @return ListHead
+
+**/
+LIST_ENTRY *
+EFIAPI
+InitializeListHead (
+ IN OUT LIST_ENTRY *List
+ )
+
+{
+ ASSERT (List != NULL);
+
+ List->ForwardLink = List;
+ List->BackLink = List;
+ return List;
+}
+
+/**
+ Adds a node to the beginning of a doubly linked list, and returns the pointer
+ to the head node of the doubly linked list.
+
+ Adds the node Entry at the beginning of the doubly linked list denoted by
+ ListHead, and returns ListHead.
+
+ If ListHead is NULL, then ASSERT().
+ If Entry is NULL, then ASSERT().
+ If ListHead was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and ListHead contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+
+ @param ListHead A pointer to the head node of a doubly linked list.
+ @param Entry A pointer to a node that is to be inserted at the beginning
+ of a doubly linked list.
+
+ @return ListHead
+
+**/
+LIST_ENTRY *
+EFIAPI
+InsertHeadList (
+ IN OUT LIST_ENTRY *List,
+ IN OUT LIST_ENTRY *Entry
+ )
+{
+ //
+ // ASSERT List not too long and Entry is not one of the nodes of List
+ //
+ ASSERT (!IsNodeInList (List, Entry));
+
+ Entry->ForwardLink = List->ForwardLink;
+ Entry->BackLink = List;
+ Entry->ForwardLink->BackLink = Entry;
+ List->ForwardLink = Entry;
+ return List;
+}
+
+/**
+ Adds a node to the end of a doubly linked list, and returns the pointer to
+ the head node of the doubly linked list.
+
+ Adds the node Entry to the end of the doubly linked list denoted by ListHead,
+ and returns ListHead.
+
+ If ListHead is NULL, then ASSERT().
+ If Entry is NULL, then ASSERT().
+ If ListHead was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and ListHead contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+
+ @param ListHead A pointer to the head node of a doubly linked list.
+ @param Entry A pointer to a node that is to be added at the end of the
+ doubly linked list.
+
+ @return ListHead
+
+**/
+LIST_ENTRY *
+EFIAPI
+InsertTailList (
+ IN OUT LIST_ENTRY *List,
+ IN OUT LIST_ENTRY *Entry
+ )
+{
+ //
+ // ASSERT List not too long and Entry is not one of the nodes of List
+ //
+ ASSERT (!IsNodeInList (List, Entry));
+
+ Entry->ForwardLink = List;
+ Entry->BackLink = List->BackLink;
+ Entry->BackLink->ForwardLink = Entry;
+ List->BackLink = Entry;
+ return List;
+}
+
+/**
+ Retrieves the first node of a doubly linked list.
+
+ Returns the first node of a doubly linked list. List must have been
+ initialized with InitializeListHead(). If List is empty, then NULL is
+ returned.
+
+ If List is NULL, then ASSERT().
+ If List was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and List contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+
+ @param List A pointer to the head node of a doubly linked list.
+
+ @return The first node of a doubly linked list.
+ @retval NULL The list is empty.
+
+**/
+LIST_ENTRY *
+EFIAPI
+GetFirstNode (
+ IN CONST LIST_ENTRY *List
+ )
+{
+ //
+ // ASSERT List not too long
+ //
+ ASSERT (IsNodeInList (List, List));
+
+ return List->ForwardLink;
+}
+
+/**
+ Retrieves the next node of a doubly linked list.
+
+ Returns the node of a doubly linked list that follows Node. List must have
+ been initialized with InitializeListHead(). If List is empty, then List is
+ returned.
+
+ If List is NULL, then ASSERT().
+ If Node is NULL, then ASSERT().
+ If List was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and List contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+ If Node is not a node in List, then ASSERT().
+
+ @param List A pointer to the head node of a doubly linked list.
+ @param Node A pointer to a node in the doubly linked list.
+
+ @return Pointer to the next node if one exists. Otherwise a null value which
+ is actually List is returned.
+
+**/
+LIST_ENTRY *
+EFIAPI
+GetNextNode (
+ IN CONST LIST_ENTRY *List,
+ IN CONST LIST_ENTRY *Node
+ )
+{
+ //
+ // ASSERT List not too long and Node is one of the nodes of List
+ //
+ ASSERT (IsNodeInList (List, Node));
+
+ return Node->ForwardLink;
+}
+
+/**
+ Checks to see if a doubly linked list is empty or not.
+
+ Checks to see if the doubly linked list is empty. If the linked list contains
+ zero nodes, this function returns TRUE. Otherwise, it returns FALSE.
+
+ If ListHead is NULL, then ASSERT().
+ If ListHead was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and List contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+
+ @param ListHead A pointer to the head node of a doubly linked list.
+
+ @retval TRUE The linked list is empty.
+ @retval FALSE The linked list is not empty.
+
+**/
+BOOLEAN
+EFIAPI
+IsListEmpty (
+ IN CONST LIST_ENTRY *List
+ )
+{
+ //
+ // ASSERT List not too long
+ //
+ ASSERT (IsNodeInList (List, List));
+
+ return (BOOLEAN)(List->ForwardLink == List);
+}
+
+/**
+ Determines if a node in a doubly linked list is null.
+
+ Returns FALSE if Node is one of the nodes in the doubly linked list specified
+ by List. Otherwise, TRUE is returned. List must have been initialized with
+ InitializeListHead().
+
+ If List is NULL, then ASSERT().
+ If Node is NULL, then ASSERT().
+ If List was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and List contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+ If Node is not a node in List and Node is not equal to List, then ASSERT().
+
+ @param List A pointer to the head node of a doubly linked list.
+ @param Node A pointer to a node in the doubly linked list.
+
+ @retval TRUE Node is one of the nodes in the doubly linked list.
+ @retval FALSE Node is not one of the nodes in the doubly linked list.
+
+**/
+BOOLEAN
+EFIAPI
+IsNull (
+ IN CONST LIST_ENTRY *List,
+ IN CONST LIST_ENTRY *Node
+ )
+{
+ //
+ // ASSERT List not too long and Node is one of the nodes of List
+ //
+ ASSERT (IsNodeInList (List, Node));
+
+ return (BOOLEAN)(Node == List);
+}
+
+/**
+ Determines if a node the last node in a doubly linked list.
+
+ Returns TRUE if Node is the last node in the doubly linked list specified by
+ List. Otherwise, FALSE is returned. List must have been initialized with
+ InitializeListHead().
+
+ If List is NULL, then ASSERT().
+ If Node is NULL, then ASSERT().
+ If List was not initialized with InitializeListHead(), then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and List contains more than
+ PcdMaximumLinkedListLenth nodes, then ASSERT().
+ If Node is not a node in List, then ASSERT().
+
+ @param List A pointer to the head node of a doubly linked list.
+ @param Node A pointer to a node in the doubly linked list.
+
+ @retval TRUE Node is the last node in the linked list.
+ @retval FALSE Node is not the last node in the linked list.
+
+**/
+BOOLEAN
+EFIAPI
+IsNodeAtEnd (
+ IN CONST LIST_ENTRY *List,
+ IN CONST LIST_ENTRY *Node
+ )
+{
+ //
+ // ASSERT List not too long and Node is one of the nodes of List
+ //
+ ASSERT (IsNodeInList (List, Node));
+
+ return (BOOLEAN)(!IsNull (List, Node) && List->BackLink == Node);
+}
+
+/**
+ Swaps the location of two nodes in a doubly linked list, and returns the
+ first node after the swap.
+
+ If FirstEntry is identical to SecondEntry, then SecondEntry is returned.
+ Otherwise, the location of the FirstEntry node is swapped with the location
+ of the SecondEntry node in a doubly linked list. SecondEntry must be in the
+ same double linked list as FirstEntry and that double linked list must have
+ been initialized with InitializeListHead(). SecondEntry is returned after the
+ nodes are swapped.
+
+ If FirstEntry is NULL, then ASSERT().
+ If SecondEntry is NULL, then ASSERT().
+ If SecondEntry and FirstEntry are not in the same linked list, then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and the linked list containing
+ FirstEntry and SecondEntry contains more than PcdMaximumLinkedListLenth
+ nodes, then ASSERT().
+
+ @param FirstEntry A pointer to a node in a linked list.
+ @param SecondEntry A pointer to another node in the same linked list.
+
+**/
+LIST_ENTRY *
+EFIAPI
+SwapListEntries (
+ IN OUT LIST_ENTRY *FirstEntry,
+ IN OUT LIST_ENTRY *SecondEntry
+ )
+{
+ LIST_ENTRY *Ptr;
+
+ if (FirstEntry == SecondEntry) {
+ return SecondEntry;
+ }
+
+ //
+ // ASSERT Entry1 and Entry2 are in the same linked list
+ //
+ ASSERT (IsNodeInList (FirstEntry, SecondEntry));
+
+ //
+ // Ptr is the node pointed to by FirstEntry->ForwardLink
+ //
+ Ptr = RemoveEntryList (FirstEntry);
+
+ //
+ // If FirstEntry immediately follows SecondEntry, FirstEntry willl be placed
+ // immediately in front of SecondEntry
+ //
+ if (Ptr->BackLink == SecondEntry) {
+ return InsertTailList (SecondEntry, FirstEntry);
+ }
+
+ //
+ // Ptr == SecondEntry means SecondEntry immediately follows FirstEntry,
+ // then there are no further steps necessary
+ //
+ if (Ptr == InsertHeadList (SecondEntry, FirstEntry)) {
+ return Ptr;
+ }
+
+ //
+ // Move SecondEntry to the front of Ptr
+ //
+ RemoveEntryList (SecondEntry);
+ InsertTailList (Ptr, SecondEntry);
+ return SecondEntry;
+}
+
+/**
+ Removes a node from a doubly linked list, and returns the node that follows
+ the removed node.
+
+ Removes the node Entry from a doubly linked list. It is up to the caller of
+ this function to release the memory used by this node if that is required. On
+ exit, the node following Entry in the doubly linked list is returned. If
+ Entry is the only node in the linked list, then the head node of the linked
+ list is returned.
+
+ If Entry is NULL, then ASSERT().
+ If Entry is the head node of an empty list, then ASSERT().
+ If PcdMaximumLinkedListLenth is not zero, and the linked list containing
+ Entry contains more than PcdMaximumLinkedListLenth nodes, then ASSERT().
+
+ @param Entry A pointer to a node in a linked list
+
+ @return Entry
+
+**/
+LIST_ENTRY *
+EFIAPI
+RemoveEntryList (
+ IN CONST LIST_ENTRY *Entry
+ )
+{
+ ASSERT (!IsListEmpty (Entry));
+
+ Entry->ForwardLink->BackLink = Entry->BackLink;
+ Entry->BackLink->ForwardLink = Entry->ForwardLink;
+ return Entry->ForwardLink;
+}
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