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/* |
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* dlink.C: Linked lists. |
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* |
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* Copyright © 2007 Pippijn van Steenhoven / The Ermyth Team |
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* Rights to this code are as documented in COPYING. |
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* |
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* |
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* Portions of this file were derived from sources bearing the following license: |
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* Rights to this code are documented in doc/pod/license.pod. |
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* Copyright © 2005-2007 Atheme Project (http://www.atheme.org) |
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*/ |
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|
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static char const rcsid[] = "$Id: dlink.C,v 1.5 2007-09-16 18:54:44 pippijn Exp $"; |
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|
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#include "atheme.h" |
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#include <ermyth/system.h> |
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#include "internal.h" |
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|
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void |
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init_dlink_nodes (void) |
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{ |
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#if 0 |
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node_heap = BlockHeapCreate (sizeof (node_t), HEAP_NODE); |
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#endif |
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} |
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|
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/* creates a new node */ |
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node_t * |
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node_create (void) |
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{ |
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node_t *n; |
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|
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/* allocate it */ |
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n = new node_t; |
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|
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/* initialize */ |
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n->data = n->next = n->prev = NULL; |
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|
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/* up the count */ |
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system_state.node++; |
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|
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/* return a pointer to the new node */ |
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return n; |
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} |
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|
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/* frees a node */ |
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void |
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node_free (node_t *n) |
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{ |
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return_if_fail (n != NULL); |
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|
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/* free it */ |
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delete n; |
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|
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/* down the count */ |
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system_state.node--; |
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} |
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|
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/* adds a node to the end of a list */ |
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void |
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node_add (void *data, node_t *n, list_t *l) |
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{ |
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node_t *tn; |
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|
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return_if_fail (n != NULL); |
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return_if_fail (l != NULL); |
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|
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n->next = n->prev = NULL; |
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n->data = data; |
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|
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/* first node? */ |
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if (!l->head) |
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{ |
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l->head = n; |
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l->tail = n; |
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l->count++; |
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return; |
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} |
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|
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/* Speed increase. */ |
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tn = l->tail; |
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|
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/* set the our `prev' to the last node */ |
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n->prev = tn; |
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|
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/* set the last node's `next' to us */ |
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n->prev->next = n; |
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|
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/* set the list's `tail' to us */ |
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l->tail = n; |
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|
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/* up the count */ |
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l->count++; |
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} |
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|
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/* adds a node to the head of a list */ |
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void |
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node_add_head (void *data, node_t *n, list_t *l) |
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{ |
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node_t *tn; |
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|
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return_if_fail (n != NULL); |
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return_if_fail (l != NULL); |
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|
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n->next = n->prev = NULL; |
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n->data = data; |
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|
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/* first node? */ |
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if (!l->head) |
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{ |
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l->head = n; |
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l->tail = n; |
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l->count++; |
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return; |
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} |
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|
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tn = l->head; |
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n->next = tn; |
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tn->prev = n; |
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l->head = n; |
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l->count++; |
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} |
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|
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/* adds a node to a list before another node, or to the end */ |
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void |
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node_add_before (void *data, node_t *n, list_t *l, node_t *before) |
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{ |
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return_if_fail (n != NULL); |
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return_if_fail (l != NULL); |
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|
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if (before == NULL) |
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node_add (data, n, l); |
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else if (before == l->head) |
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node_add_head (data, n, l); |
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else |
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{ |
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n->data = data; |
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n->prev = before->prev; |
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n->next = before; |
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before->prev = n; |
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l->count++; |
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} |
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} |
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|
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void |
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node_del (node_t *n, list_t *l) |
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{ |
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return_if_fail (n != NULL); |
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return_if_fail (l != NULL); |
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|
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/* are we the head? */ |
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if (!n->prev) |
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l->head = n->next; |
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else |
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n->prev->next = n->next; |
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|
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/* are we the tail? */ |
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if (!n->next) |
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l->tail = n->prev; |
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else |
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n->next->prev = n->prev; |
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|
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/* down the count */ |
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l->count--; |
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} |
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|
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/* finds a node by `data' */ |
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node_t * |
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node_find (void *data, list_t *l) |
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{ |
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node_t *n; |
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|
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return_val_if_fail (l != NULL, NULL); |
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|
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LIST_FOREACH (n, l->head) |
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if (n->data == data) |
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return n; |
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|
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return NULL; |
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} |
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|
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void |
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node_move (node_t *m, list_t *oldlist, list_t *newlist) |
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{ |
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return_if_fail (m != NULL); |
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return_if_fail (oldlist != NULL); |
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return_if_fail (newlist != NULL); |
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|
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/* Assumption: If m->next == NULL, then list->tail == m |
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* and: If m->prev == NULL, then list->head == m |
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*/ |
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if (m->next) |
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m->next->prev = m->prev; |
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else |
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oldlist->tail = m->prev; |
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|
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if (m->prev) |
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m->prev->next = m->next; |
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else |
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oldlist->head = m->next; |
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|
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m->prev = NULL; |
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m->next = newlist->head; |
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if (newlist->head != NULL) |
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newlist->head->prev = m; |
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else if (newlist->tail == NULL) |
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newlist->tail = m; |
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newlist->head = m; |
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|
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oldlist->count--; |
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newlist->count++; |
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} |
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|
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/* vim:cinoptions=>s,e0,n0,f0,{0,}0,^0,=s,ps,t0,c3,+s,(2s,us,)20,*30,gs,hs |
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* vim:ts=8 |
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* vim:sw=8 |
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* vim:noexpandtab |
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*/ |
