mirror of https://github.com/acidanthera/audk.git
551 lines
17 KiB
C
551 lines
17 KiB
C
/** @file
|
|
Linked List Library Functions.
|
|
|
|
Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR>
|
|
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.
|
|
|
|
**/
|
|
|
|
#include "BaseLibInternals.h"
|
|
|
|
/**
|
|
Worker function that locates the Node in the List.
|
|
|
|
By searching the List, finds the location of the Node in List. At the same time,
|
|
verifies the validity of this list.
|
|
|
|
If List is NULL, then ASSERT().
|
|
If List->ForwardLink is NULL, then ASSERT().
|
|
If List->backLink is NULL, then ASSERT().
|
|
If Node is NULL, then ASSERT().
|
|
If PcdVerifyNodeInList is TRUE and DoMembershipCheck is TRUE and Node
|
|
is in not a member of List, then return FALSE
|
|
If PcdMaximumLinkedListLength is not zero, and List contains more than
|
|
PcdMaximumLinkedListLength nodes, then ASSERT().
|
|
|
|
@param List A pointer to a node in a linked list.
|
|
@param Node A pointer to a node in a linked list.
|
|
@param VerifyNodeInList TRUE if a check should be made to see if Node is a
|
|
member of List. FALSE if no membership test should
|
|
be performed.
|
|
|
|
@retval TRUE if PcdVerifyNodeInList is FALSE
|
|
@retval TRUE if DoMembershipCheck is FALSE
|
|
@retval TRUE if PcdVerifyNodeInList is TRUE and DoMembershipCheck is TRUE
|
|
and Node is a member of List.
|
|
@retval FALSE if PcdVerifyNodeInList is TRUE and DoMembershipCheck is TRUE
|
|
and Node is in not a member of List.
|
|
|
|
**/
|
|
BOOLEAN
|
|
EFIAPI
|
|
InternalBaseLibIsNodeInList (
|
|
IN CONST LIST_ENTRY *List,
|
|
IN CONST LIST_ENTRY *Node,
|
|
IN BOOLEAN VerifyNodeInList
|
|
)
|
|
{
|
|
UINTN Count;
|
|
CONST LIST_ENTRY *Ptr;
|
|
|
|
//
|
|
// Test the validity of List and Node
|
|
//
|
|
ASSERT (List != NULL);
|
|
ASSERT (List->ForwardLink != NULL);
|
|
ASSERT (List->BackLink != NULL);
|
|
ASSERT (Node != NULL);
|
|
|
|
Count = 0;
|
|
Ptr = List;
|
|
|
|
if (FeaturePcdGet (PcdVerifyNodeInList) && VerifyNodeInList) {
|
|
//
|
|
// Check to see if Node is a member of List.
|
|
// Exit early if the number of nodes in List >= PcdMaximumLinkedListLength
|
|
//
|
|
do {
|
|
Ptr = Ptr->ForwardLink;
|
|
if (PcdGet32 (PcdMaximumLinkedListLength) > 0) {
|
|
Count++;
|
|
//
|
|
// ASSERT() if the linked list is too long
|
|
//
|
|
ASSERT (Count < PcdGet32 (PcdMaximumLinkedListLength));
|
|
|
|
//
|
|
// Return if the linked list is too long
|
|
//
|
|
if (Count >= PcdGet32 (PcdMaximumLinkedListLength)) {
|
|
return (BOOLEAN)(Ptr == Node);
|
|
}
|
|
}
|
|
} while ((Ptr != List) && (Ptr != Node));
|
|
|
|
if (Ptr != Node) {
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
if (PcdGet32 (PcdMaximumLinkedListLength) > 0) {
|
|
//
|
|
// Count the total number of nodes in List.
|
|
// Exit early if the number of nodes in List >= PcdMaximumLinkedListLength
|
|
//
|
|
do {
|
|
Ptr = Ptr->ForwardLink;
|
|
Count++;
|
|
} while ((Ptr != List) && (Count < PcdGet32 (PcdMaximumLinkedListLength)));
|
|
|
|
//
|
|
// ASSERT() if the linked list is too long
|
|
//
|
|
ASSERT (Count < PcdGet32 (PcdMaximumLinkedListLength));
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
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 *ListHead
|
|
)
|
|
|
|
{
|
|
ASSERT (ListHead != NULL);
|
|
|
|
ListHead->ForwardLink = ListHead;
|
|
ListHead->BackLink = ListHead;
|
|
return ListHead;
|
|
}
|
|
|
|
/**
|
|
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 INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and prior to insertion the number
|
|
of nodes in ListHead, including the ListHead node, is greater than or
|
|
equal to PcdMaximumLinkedListLength, 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 *ListHead,
|
|
IN OUT LIST_ENTRY *Entry
|
|
)
|
|
{
|
|
//
|
|
// ASSERT List not too long and Entry is not one of the nodes of List
|
|
//
|
|
ASSERT (InternalBaseLibIsNodeInList (ListHead, Entry, FALSE));
|
|
|
|
Entry->ForwardLink = ListHead->ForwardLink;
|
|
Entry->BackLink = ListHead;
|
|
Entry->ForwardLink->BackLink = Entry;
|
|
ListHead->ForwardLink = Entry;
|
|
return ListHead;
|
|
}
|
|
|
|
/**
|
|
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 INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and prior to insertion the number
|
|
of nodes in ListHead, including the ListHead node, is greater than or
|
|
equal to PcdMaximumLinkedListLength, 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 *ListHead,
|
|
IN OUT LIST_ENTRY *Entry
|
|
)
|
|
{
|
|
//
|
|
// ASSERT List not too long and Entry is not one of the nodes of List
|
|
//
|
|
ASSERT (InternalBaseLibIsNodeInList (ListHead, Entry, FALSE));
|
|
|
|
Entry->ForwardLink = ListHead;
|
|
Entry->BackLink = ListHead->BackLink;
|
|
Entry->BackLink->ForwardLink = Entry;
|
|
ListHead->BackLink = Entry;
|
|
return ListHead;
|
|
}
|
|
|
|
/**
|
|
Retrieves the first node of a doubly-linked list.
|
|
|
|
Returns the first node of a doubly-linked list. List must have been
|
|
initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
|
|
If List is empty, then List is returned.
|
|
|
|
If List is NULL, then ASSERT().
|
|
If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and the number of nodes
|
|
in List, including the List node, is greater than or equal to
|
|
PcdMaximumLinkedListLength, 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 List The list is empty.
|
|
|
|
**/
|
|
LIST_ENTRY *
|
|
EFIAPI
|
|
GetFirstNode (
|
|
IN CONST LIST_ENTRY *List
|
|
)
|
|
{
|
|
//
|
|
// ASSERT List not too long
|
|
//
|
|
ASSERT (InternalBaseLibIsNodeInList (List, List, FALSE));
|
|
|
|
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 INTIALIZE_LIST_HEAD_VARIABLE()
|
|
or 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 INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and List contains more than
|
|
PcdMaximumLinkedListLength nodes, then ASSERT().
|
|
If PcdVerifyNodeInList is TRUE and 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 A pointer to the next node if one exists. Otherwise 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 (InternalBaseLibIsNodeInList (List, Node, TRUE));
|
|
|
|
return Node->ForwardLink;
|
|
}
|
|
|
|
/**
|
|
Retrieves the previous node of a doubly-linked list.
|
|
|
|
Returns the node of a doubly-linked list that precedes Node.
|
|
List must have been initialized with INTIALIZE_LIST_HEAD_VARIABLE()
|
|
or 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 INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and List contains more than
|
|
PcdMaximumLinkedListLength nodes, then ASSERT().
|
|
If PcdVerifyNodeInList is TRUE and 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 A pointer to the previous node if one exists. Otherwise List is returned.
|
|
|
|
**/
|
|
LIST_ENTRY *
|
|
EFIAPI
|
|
GetPreviousNode (
|
|
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 (InternalBaseLibIsNodeInList (List, Node, TRUE));
|
|
|
|
return Node->BackLink;
|
|
}
|
|
|
|
/**
|
|
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 INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and the number of nodes
|
|
in List, including the List node, is greater than or equal to
|
|
PcdMaximumLinkedListLength, 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 *ListHead
|
|
)
|
|
{
|
|
//
|
|
// ASSERT List not too long
|
|
//
|
|
ASSERT (InternalBaseLibIsNodeInList (ListHead, ListHead, FALSE));
|
|
|
|
return (BOOLEAN)(ListHead->ForwardLink == ListHead);
|
|
}
|
|
|
|
/**
|
|
Determines if a node in a doubly-linked list is the head node of a the same
|
|
doubly-linked list. This function is typically used to terminate a loop that
|
|
traverses all the nodes in a doubly-linked list starting with the head node.
|
|
|
|
Returns TRUE if Node is equal to List. Returns FALSE if Node is one of the
|
|
nodes in the doubly-linked list specified by List. List must have been
|
|
initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
|
|
|
|
If List is NULL, then ASSERT().
|
|
If Node is NULL, then ASSERT().
|
|
If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead(),
|
|
then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and the number of nodes
|
|
in List, including the List node, is greater than or equal to
|
|
PcdMaximumLinkedListLength, then ASSERT().
|
|
If PcdVerifyNodeInList is TRUE and 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 the head of the doubly-linked list pointed by List.
|
|
@retval FALSE Node is not the head of the doubly-linked list pointed by 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 (InternalBaseLibIsNodeInList (List, Node, TRUE));
|
|
|
|
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
|
|
INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
|
|
|
|
If List is NULL, then ASSERT().
|
|
If Node is NULL, then ASSERT().
|
|
If List was not initialized with INTIALIZE_LIST_HEAD_VARIABLE() or
|
|
InitializeListHead(), then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and the number of nodes
|
|
in List, including the List node, is greater than or equal to
|
|
PcdMaximumLinkedListLength, then ASSERT().
|
|
If PcdVerifyNodeInList is TRUE and 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 (InternalBaseLibIsNodeInList (List, Node, TRUE));
|
|
|
|
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 INTIALIZE_LIST_HEAD_VARIABLE() or InitializeListHead().
|
|
SecondEntry is returned after the nodes are swapped.
|
|
|
|
If FirstEntry is NULL, then ASSERT().
|
|
If SecondEntry is NULL, then ASSERT().
|
|
If PcdVerifyNodeInList is TRUE and SecondEntry and FirstEntry are not in the
|
|
same linked list, then ASSERT().
|
|
If PcdMaximumLinkedListLength is not zero, and the number of nodes in the
|
|
linked list containing the FirstEntry and SecondEntry nodes, including
|
|
the FirstEntry and SecondEntry nodes, is greater than or equal to
|
|
PcdMaximumLinkedListLength, 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.
|
|
|
|
@return SecondEntry.
|
|
|
|
**/
|
|
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 (InternalBaseLibIsNodeInList (FirstEntry, SecondEntry, TRUE));
|
|
|
|
//
|
|
// Ptr is the node pointed to by FirstEntry->ForwardLink
|
|
//
|
|
Ptr = RemoveEntryList (FirstEntry);
|
|
|
|
//
|
|
// If FirstEntry immediately follows SecondEntry, FirstEntry will 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 PcdMaximumLinkedListLength is not zero, and the number of nodes in the
|
|
linked list containing Entry, including the Entry node, is greater than
|
|
or equal to PcdMaximumLinkedListLength, 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;
|
|
}
|