--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/tkDList.h	Tue Mar 18 17:55:14 2025 -0400
@@ -0,0 +1,546 @@
+/*
+ * tkDList.h --
+ *
+ * A list is headed by pointers to first and last element. The elements
+ * are doubly linked so that an arbitrary element can be removed without
+ * a need to traverse the list. New elements can be added to the list
+ * before or after an existing element or at the head/tail of the list.
+ * A list may be traversed in the forward or backward direction.
+ *
+ * Copyright (c) 2018 by Gregor Cramer.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+/*
+ * Note that this file will not be included in header files, it is the purpose
+ * of this file to be included in source files only. Thus we are not using the
+ * prefix "Tk_" here for functions, because all the functions have private scope.
+ */
+
+/*
+ * -------------------------------------------------------------------------------
+ * Use the double linked list in the following way:
+ * -------------------------------------------------------------------------------
+ * typedef struct MyListEntry { TK_DLIST_LINKS(MyListEntry); int value; } MyListEntry;
+ * TK_DLIST_DEFINE(MyList, MyListEntry);
+ * MyList listHdr = TK_DLIST_LIST_INITIALIZER; // or MyList_Init(&listHdr)
+ * MyListEntry *p;
+ * int i = 0;
+ * MyList_Append(&listHdr, ckalloc(sizeof(MyListEntry)));
+ * MyList_Append(&listHdr, ckalloc(sizeof(MyListEntry)));
+ * TK_DLIST_FOREACH(p, &listHdr) { p->value = i++; }
+ * // ...
+ * MyList_RemoveHead(&listHdr);
+ * MyList_RemoveHead(&listHdr);
+ * MyList_Clear(MyListEntry, &listHdr); // invokes ckfree() for each element
+ * -------------------------------------------------------------------------------
+ * IMPORTANT NOTE: TK_DLIST_LINKS must be used at start of struct!
+ */
+
+#ifndef TK_DLIST_DEFINED
+#define TK_DLIST_DEFINED
+
+#include "tkInt.h"
+
+/*
+ * List definitions.
+ */
+
+#define TK_DLIST_LINKS(ElemType)						\
+struct {									\
+    struct ElemType *prev;	/* previous element */				\
+    struct ElemType *next;	/* next element */				\
+} _dl_
+
+#define TK_DLIST_LIST_INITIALIZER { NULL, NULL }
+#define TK_DLIST_ELEM_INITIALIZER { NULL, NULL }
+
+/*************************************************************************/
+/*
+ * DList_Init: Initialize list header. This can also be used to clear the
+ * list.
+ *
+ * See also: DList_Clear()
+ */
+/*************************************************************************/
+/*
+ * DList_ElemInit: Initialize a list element.
+ */
+/*************************************************************************/
+/*
+ * DList_InsertAfter: Insert 'elem' after 'listElem'. 'elem' must not
+ * be linked, but 'listElem' must be linked.
+ */
+/*************************************************************************/
+/*
+ * DList_InsertBefore: Insert 'elem' before 'listElem'. 'elem' must not
+ * be linked, but 'listElem' must be linked.
+ */
+/*************************************************************************/
+/*
+ * DList_Prepend: Insert 'elem' at start of list. This element must not
+ * be linked.
+ *
+ * See also: DList_Append()
+ */
+/*************************************************************************/
+/*
+ * DList_Append: Append 'elem' to end of list. This element must not
+ * be linked.
+ *
+ * See also: DList_Prepend()
+ */
+/*************************************************************************/
+/*
+ * DList_Move: Append all list items of 'src' to end of 'dst'.
+ */
+/*************************************************************************/
+/*
+ * DList_Remove: Remove 'elem' from list. This element must be linked.
+ *
+ * See also: DList_Free()
+ */
+/*************************************************************************/
+/*
+ * DList_Free: Remove 'elem' from list and free it. This element must
+ * be linked.
+ *
+ * See also: DList_Remove()
+ */
+/*************************************************************************/
+/*
+ * DList_RemoveHead: Remove first element from list. The list must
+ * not be empty.
+ *
+ * See also: DList_FreeHead()
+ */
+/*************************************************************************/
+/*
+ * DList_RemoveTail: Remove last element from list. The list must
+ * not be empty.
+ *
+ * See also: DList_FreeTail()
+ */
+/*************************************************************************/
+/*
+ * DList_FreeHead: Remove first element from list and free it.
+ * The list must not be empty.
+ *
+ * See also: DList_RemoveHead()
+ */
+/*************************************************************************/
+/*
+ * DList_FreeTail: Remove last element from list and free it.
+ * The list must not be empty.
+ *
+ * See also: DList_RemoveTail()
+ */
+/*************************************************************************/
+/*
+ * DList_SwapElems: Swap positions of given elements 'lhs' and 'rhs'.
+ * Both elements must be linked, and must belong to same list.
+ */
+/*************************************************************************/
+/*
+ * DList_Clear: Clear whole list and free all elements.
+ *
+ * See also: DList_Init
+ */
+/*************************************************************************/
+/*
+ * DList_Traverse: Iterate over all elements in list from first to last.
+ * Call given function func(head, elem) for each element. The function has
+ * to return the next element in list to traverse, normally this is
+ * DList_Next(elem).
+ *
+ * See also: TK_DLIST_FOREACH, TK_DLIST_FOREACH_REVERSE
+ */
+/*************************************************************************/
+/*
+ * DList_First: Return pointer of first element in list, maybe it's NULL.
+ */
+/*************************************************************************/
+/*
+ * DList_Last: Return pointer of last element in list, maybe it's NULL.
+ */
+/*************************************************************************/
+/*
+ * DList_Next: Return pointer of next element after 'elem', maybe it's NULL.
+ *
+ * See also: DList_Prev()
+ */
+/*************************************************************************/
+/*
+ * DList_Prev: Return pointer of previous element before 'elem', maybe it's
+ * NULL.
+ *
+ * See also: DList_Next()
+ */
+/*************************************************************************/
+/*
+ * DList_IsEmpty: Test whether given list is empty.
+ */
+/*************************************************************************/
+/*
+ * DList_IsLinked: Test whether given element is linked.
+ */
+/*************************************************************************/
+/*
+ * DList_IsFirst: Test whether given element is first element in list.
+ * Note that 'elem' must be linked.
+ *
+ * See also: DList_IsLast(), DList_IsLinked()
+ */
+/*************************************************************************/
+/*
+ * DList_IsLast: Test whether given element is last element in list.
+ * Note that 'elem' must be linked.
+ *
+ * See also: DList_IsFirst(), DList_IsLinked()
+ */
+/*************************************************************************/
+/*
+ * DList_Size: Count number of elements in given list.
+ */
+/*************************************************************************/
+/*
+ * TK_DLIST_FOREACH: Iterate over all elements in list from first to last.
+ * 'var' is the name of the variable which points to current element.
+ *
+ * See also: TK_DLIST_FOREACH_REVERSE, DList_Traverse()
+ */
+/*************************************************************************/
+/*
+ * TK_DLIST_FOREACH_REVERSE: Iterate over all elements in list from last
+ * to first (backwards). 'var' is the name of the variable which points to
+ * current element.
+ */
+/*************************************************************************/
+
+#if defined(__GNUC__) || defined(__clang__)
+# define __TK_DLIST_UNUSED __attribute__((unused))
+#else
+# define __TK_DLIST_UNUSED
+#endif
+
+#define TK_DLIST_DEFINE(LT, ElemType) /* LT = type of head/list */		\
+/* ------------------------------------------------------------------------- */	\
+typedef struct LT {								\
+    struct ElemType *first;	/* first element */				\
+    struct ElemType *last;	/* last element */				\
+} LT;										\
+										\
+typedef struct ElemType *(LT##_Func)(LT *head, struct ElemType *elem);		\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Init(LT *head)								\
+{										\
+    assert(head);								\
+    head->first = NULL;								\
+    head->last = NULL;								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_ElemInit(struct ElemType *elem)						\
+{										\
+    assert(elem);								\
+    elem->_dl_.next = NULL;							\
+    elem->_dl_.prev = NULL;							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static int									\
+LT##_IsEmpty(LT *head)								\
+{										\
+    assert(head);								\
+    return head->first == NULL;							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static int									\
+LT##_IsLinked(struct ElemType *elem)						\
+{										\
+    assert(elem);								\
+    return elem->_dl_.next && elem->_dl_.prev;					\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static int									\
+LT##_IsFirst(struct ElemType *elem)						\
+{										\
+    assert(LT##_IsLinked(elem));						\
+    return elem->_dl_.prev->_dl_.prev == elem;					\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static int									\
+LT##_IsLast(struct ElemType *elem)						\
+{										\
+    assert(LT##_IsLinked(elem));						\
+    return elem->_dl_.next->_dl_.next == elem;					\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static struct ElemType *							\
+LT##_First(LT *head)								\
+{										\
+    assert(head);								\
+    return head->first;								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static struct ElemType *							\
+LT##_Last(LT *head)								\
+{										\
+    assert(head);								\
+    return head->last;								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static struct ElemType *							\
+LT##_Next(struct ElemType *elem)						\
+{										\
+    assert(elem);								\
+    return LT##_IsLast(elem) ? NULL : elem->_dl_.next;				\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static struct ElemType *							\
+LT##_Prev(struct ElemType *elem)						\
+{										\
+    assert(elem);								\
+    return LT##_IsFirst(elem) ? NULL : elem->_dl_.prev;				\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static unsigned									\
+LT##_Size(const LT *head)							\
+{										\
+    const struct ElemType *elem;						\
+    unsigned size = 0;								\
+    assert(head);								\
+    if ((elem = head->first)) {							\
+	for ( ; elem != (void *) head; elem = elem->_dl_.next) {		\
+	    ++size;								\
+	}									\
+    }										\
+    return size;								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_InsertAfter(struct ElemType *listElem, struct ElemType *elem)		\
+{										\
+    assert(listElem);								\
+    assert(elem);								\
+    elem->_dl_.next = listElem->_dl_.next;					\
+    elem->_dl_.prev = listElem;							\
+    listElem->_dl_.next->_dl_.prev = elem;					\
+    listElem->_dl_.next = elem;							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_InsertBefore(struct ElemType *listElem, struct ElemType *elem)		\
+{										\
+    assert(listElem);								\
+    assert(elem);								\
+    elem->_dl_.next = listElem;							\
+    elem->_dl_.prev = listElem->_dl_.prev;;					\
+    listElem->_dl_.prev->_dl_.next = elem;					\
+    listElem->_dl_.prev = elem;							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Prepend(LT *head, struct ElemType *elem)					\
+{										\
+    assert(head);								\
+    assert(elem);								\
+    elem->_dl_.prev = (void *) head;						\
+    if (!head->first) {								\
+	elem->_dl_.next = (void *) head;					\
+	head->last = elem;							\
+    } else {									\
+	elem->_dl_.next = head->first;						\
+	head->first->_dl_.prev = elem;						\
+    }										\
+    head->first = elem;								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Append(LT *head, struct ElemType *elem)					\
+{										\
+    assert(head);								\
+    assert(elem);								\
+    elem->_dl_.next = (void *) head;						\
+    if (!head->first) {								\
+	elem->_dl_.prev = (void *) head;					\
+	head->first = elem;							\
+    } else {									\
+	elem->_dl_.prev = head->last;						\
+	head->last->_dl_.next = elem;						\
+    }										\
+    head->last = elem;								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Move(LT *dst, LT *src)							\
+{										\
+    assert(dst);								\
+    assert(src);								\
+    if (src->first) {								\
+	if (dst->first) {							\
+	    dst->last->_dl_.next = src->first;					\
+	    src->first->_dl_.prev = dst->last;					\
+	    dst->last = src->last;						\
+	} else {								\
+	    *dst = *src;							\
+	    dst->first->_dl_.prev = (void *) dst;				\
+	}									\
+	dst->last->_dl_.next = (void *) dst;					\
+	LT##_Init(src);								\
+    }										\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Remove(struct ElemType *elem)						\
+{										\
+    int isFirst, isLast;							\
+    assert(LT##_IsLinked(elem));						\
+    isFirst = LT##_IsFirst(elem);						\
+    isLast = LT##_IsLast(elem);							\
+    if (isFirst && isLast) {							\
+	((LT *) elem->_dl_.prev)->first = NULL;					\
+	((LT *) elem->_dl_.next)->last = NULL;					\
+    } else {									\
+	if (isFirst) {								\
+	    ((LT *) elem->_dl_.prev)->first = elem->_dl_.next;			\
+	} else {								\
+	    elem->_dl_.prev->_dl_.next = elem->_dl_.next;			\
+	}									\
+	if (isLast) {								\
+	    ((LT *) elem->_dl_.next)->last = elem->_dl_.prev;			\
+	} else {								\
+	    elem->_dl_.next->_dl_.prev = elem->_dl_.prev;			\
+	}									\
+    }										\
+    LT##_ElemInit(elem);							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Free(struct ElemType *elem)						\
+{										\
+    LT##_Remove(elem);								\
+    ckfree((void *) elem);							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_RemoveHead(LT *head)							\
+{										\
+    assert(!LT##_IsEmpty(head));						\
+    LT##_Remove(head->first);							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_RemoveTail(LT *head)							\
+{										\
+    assert(!LT##_IsEmpty(head));						\
+    LT##_Remove(head->last);							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_FreeHead(LT *head)								\
+{										\
+    assert(!LT##_IsEmpty(head));						\
+    LT##_Free(head->first);							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_FreeTail(LT *head)								\
+{										\
+    assert(!LT##_IsEmpty(head));						\
+    LT##_Free(head->last);							\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_SwapElems(struct ElemType *lhs, struct ElemType *rhs)			\
+{										\
+    assert(lhs);								\
+    assert(rhs);								\
+    if (lhs != rhs) {								\
+	struct ElemType tmp;							\
+	if (LT##_IsFirst(lhs))  {						\
+	    ((LT *) lhs->_dl_.prev)->first = rhs;				\
+	} else if (LT##_IsFirst(rhs)) {						\
+	    ((LT *) rhs->_dl_.prev)->first = lhs;				\
+	}									\
+	if (LT##_IsLast(lhs))  {						\
+	    ((LT *) lhs->_dl_.next)->last = rhs;				\
+	} else if (LT##_IsLast(rhs)) {						\
+	    ((LT *) rhs->_dl_.next)->last = lhs;				\
+	}									\
+	tmp._dl_ = lhs->_dl_;							\
+	lhs->_dl_ = rhs->_dl_;							\
+	rhs->_dl_ = tmp._dl_;							\
+    }										\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Clear(LT *head)								\
+{										\
+    struct ElemType *p;								\
+    struct ElemType *next;							\
+    assert(head);								\
+    for (p = head->first; p; p = next) {					\
+	next = LT##_Next(p);							\
+	ckfree((void *) p);							\
+    }										\
+    LT##_Init(head);								\
+}										\
+										\
+__TK_DLIST_UNUSED								\
+static void									\
+LT##_Traverse(LT *head, LT##_Func func)						\
+{										\
+    struct ElemType *next;							\
+    struct ElemType *p;								\
+    assert(head);								\
+    for (p = head->first; p; p = next) {					\
+	next = func(head, p);							\
+    }										\
+}										\
+/* ------------------------------------------------------------------------- */
+
+#define TK_DLIST_FOREACH(var, head)						\
+    assert(head);								\
+    for (var = head->first ? head->first : (void *) head; var != (void *) head; var = var->_dl_.next)
+
+#define TK_DLIST_FOREACH_REVERSE(var, head)					\
+    assert(head);								\
+    for (var = head->last ? head->last : (void *) head; var != (void *) head; var = var->_dl_.prev)
+
+#endif /* TK_DLIST_DEFINED */
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 105
+ * End:
+ * vi:set ts=8 sw=4:
+ */