Diff: doublylinkedlist.c

Revision:

0:fa2de1b79154

Child:

19:2e0811512ceb

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doublylinkedlist.c	Fri Apr 08 12:01:36 2016 -0700
@@ -0,0 +1,111 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+#include <stdlib.h>
+#ifdef _CRTDBG_MAP_ALLOC
+#include <crtdbg.h>
+#endif
+#include "azure_c_shared_utility/doublylinkedlist.h"
+
+void
+DList_InitializeListHead(
+    PDLIST_ENTRY ListHead
+)
+{
+    /* Codes_SRS_DLIST_06_005: [DList_InitializeListHead will initialize the Flink & Blink to the address of the DLIST_ENTRY.] */
+    ListHead->Flink = ListHead->Blink = ListHead;
+    return;
+}
+
+int
+DList_IsListEmpty(
+    const PDLIST_ENTRY ListHead
+)
+{
+    /* Codes_SRS_DLIST_06_003: [DList_IsListEmpty shall return a non-zero value if there are no DLIST_ENTRY's on this list other than the list head.] */
+    /* Codes_SRS_DLIST_06_004: [DList_IsListEmpty shall return 0 if there is one or more items in the list.] */
+    return (ListHead->Flink == ListHead);
+}
+
+int
+DList_RemoveEntryList(
+    PDLIST_ENTRY Entry
+)
+{
+    /* Codes_SRS_DLIST_06_008: [DList_RemoveEntryList shall remove a listEntry from whatever list it is properly part of.] */
+    /* Codes_SRS_DLIST_06_009: [The remaining list is properly formed.] */
+    /* Codes_SRS_DLIST_06_010: [DList_RemoveEntryList shall return non-zero if the remaining list is empty.] */
+    /* Codes_SRS_DLIST_06_011: [DList_RemoveEntryList shall return zero if the remaining list is NOT empty.] */
+    PDLIST_ENTRY Blink;
+    PDLIST_ENTRY Flink;
+
+    Flink = Entry->Flink;
+    Blink = Entry->Blink;
+    Blink->Flink = Flink;
+    Flink->Blink = Blink;
+    return (Flink == Blink);
+}
+
+PDLIST_ENTRY
+DList_RemoveHeadList(
+    PDLIST_ENTRY ListHead
+)
+{
+    /* Codes_SRS_DLIST_06_012: [DList_RemoveHeadList removes the oldest entry from the list defined by the listHead parameter and returns a pointer to that entry.] */
+    /* Codes_SRS_DLIST_06_013: [DList_RemoveHeadList shall return listHead if that's the only item in the list.] */
+
+    PDLIST_ENTRY Flink;
+    PDLIST_ENTRY Entry;
+
+    Entry = ListHead->Flink;
+    Flink = Entry->Flink;
+    ListHead->Flink = Flink;
+    Flink->Blink = ListHead;
+    return Entry;
+}
+
+
+
+void
+DList_InsertTailList(
+    PDLIST_ENTRY ListHead,
+    PDLIST_ENTRY Entry
+)
+{
+    PDLIST_ENTRY Blink;
+
+    /* Codes_SRS_DLIST_06_006: [DListInsertTailList shall place the DLIST_ENTRY at the end of the list defined by the listHead parameter.] */
+    Blink = ListHead->Blink;
+    Entry->Flink = ListHead;
+    Entry->Blink = Blink;
+    Blink->Flink = Entry;
+    ListHead->Blink = Entry;
+    return;
+}
+
+
+void
+DList_AppendTailList(
+    PDLIST_ENTRY ListHead,
+    PDLIST_ENTRY ListToAppend
+)
+{
+    /* Codes_SRS_DLIST_06_007: [DList_AppendTailList shall place the list defined by listToAppend at the end of the list defined by the listHead parameter.] */
+    PDLIST_ENTRY ListEnd = ListHead->Blink;
+
+    ListHead->Blink->Flink = ListToAppend;
+    ListHead->Blink = ListToAppend->Blink;
+    ListToAppend->Blink->Flink = ListHead;
+    ListToAppend->Blink = ListEnd;
+    return;
+}
+
+
+/*Codes_SRS_DLIST_02_002: [DList_InsertHeadList inserts a singular entry in the list having as head listHead after "head".]*/
+void DList_InsertHeadList(PDLIST_ENTRY listHead, PDLIST_ENTRY entry)
+{
+    entry->Blink = listHead;
+    entry->Flink = listHead->Flink;
+    listHead->Flink->Blink = entry;
+    listHead->Flink = entry;
+}