[SCM] CTDB repository - branch 112-patches updated - d528c05948149c63f4c20c472d59b21a3a1dc529
Andrew Tridgell
tridge at samba.org
Sun Feb 7 01:03:09 MST 2010
The branch, 112-patches has been updated
via d528c05948149c63f4c20c472d59b21a3a1dc529 (commit)
from 64fb20dcfcff5bc067d97bff39e491e40ca45a3f (commit)
http://gitweb.samba.org/?p=tridge/ctdb.git;a=shortlog;h=112-patches
- Log -----------------------------------------------------------------
commit d528c05948149c63f4c20c472d59b21a3a1dc529
Author: Andrew Tridgell <tridge at samba.org>
Date: Sun Feb 7 19:02:06 2010 +1100
ctdb: migrate to new dlinklist.h from Samba
-----------------------------------------------------------------------
Summary of changes:
common/ctdb_io.c | 7 +-
lib/util/dlinklist.h | 194 ++++++++++++++++++++++++++++----------------------
2 files changed, 111 insertions(+), 90 deletions(-)
Changeset truncated at 500 lines:
diff --git a/common/ctdb_io.c b/common/ctdb_io.c
index 3fa784d..b7feed9 100644
--- a/common/ctdb_io.c
+++ b/common/ctdb_io.c
@@ -194,8 +194,7 @@ static void queue_io_write(struct ctdb_queue *queue)
if (n == -1 && errno != EAGAIN && errno != EWOULDBLOCK) {
if (pkt->length != pkt->full_length) {
/* partial packet sent - we have to drop it */
- TLIST_REMOVE(queue->out_queue, queue->out_queue_tail,
- pkt);
+ DLIST_REMOVE(queue->out_queue, pkt);
queue->out_queue_length--;
talloc_free(pkt);
}
@@ -214,7 +213,7 @@ static void queue_io_write(struct ctdb_queue *queue)
return;
}
- TLIST_REMOVE(queue->out_queue, queue->out_queue_tail, pkt);
+ DLIST_REMOVE(queue->out_queue, pkt);
queue->out_queue_length--;
talloc_free(pkt);
}
@@ -295,7 +294,7 @@ int ctdb_queue_send(struct ctdb_queue *queue, uint8_t *data, uint32_t length)
EVENT_FD_WRITEABLE(queue->fde);
}
- TLIST_ADD_END(queue->out_queue, queue->out_queue_tail, pkt);
+ DLIST_ADD_END(queue->out_queue, pkt, NULL);
queue->out_queue_length++;
diff --git a/lib/util/dlinklist.h b/lib/util/dlinklist.h
index 44747d6..6d525f9 100644
--- a/lib/util/dlinklist.h
+++ b/lib/util/dlinklist.h
@@ -1,7 +1,8 @@
/*
Unix SMB/CIFS implementation.
some simple double linked list macros
- Copyright (C) Andrew Tridgell 1998
+
+ Copyright (C) Andrew Tridgell 1998-2010
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -14,7 +15,7 @@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, see <http://www.gnu.org/licenses/>.
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/* To use these macros you must have a structure containing a next and
@@ -23,55 +24,94 @@
#ifndef _DLINKLIST_H
#define _DLINKLIST_H
+/*
+ February 2010 - changed list format to have a prev pointer from the
+ list head. This makes DLIST_ADD_END() O(1) even though we only have
+ one list pointer.
+
+ The scheme is as follows:
+
+ 1) with no entries in the list:
+ list_head == NULL
+
+ 2) with 1 entry in the list:
+ list_head->next == NULL
+ list_head->prev == list_head
+
+ 3) with 2 entries in the list:
+ list_head->next == element2
+ list_head->prev == element2
+ element2->prev == list_head
+ element2->next == NULL
+
+ 4) with N entries in the list:
+ list_head->next == element2
+ list_head->prev == elementN
+ elementN->prev == element{N-1}
+ elementN->next == NULL
-/* hook into the front of the list */
+ This allows us to find the tail of the list by using
+ list_head->prev, which means we can add to the end of the list in
+ O(1) time
+
+
+ Note that the 'type' arguments below are no longer needed, but
+ are kept for now to prevent an incompatible argument change
+ */
+
+
+/*
+ add an element at the front of a list
+*/
#define DLIST_ADD(list, p) \
do { \
if (!(list)) { \
- (list) = (p); \
- (p)->next = (p)->prev = NULL; \
+ (p)->prev = (list) = (p); \
+ (p)->next = NULL; \
} else { \
+ (p)->prev = (list)->prev; \
(list)->prev = (p); \
(p)->next = (list); \
- (p)->prev = NULL; \
(list) = (p); \
- }\
+ } \
} while (0)
-/* remove an element from a list - element doesn't have to be in list. */
+/*
+ remove an element from a list
+ Note that the element doesn't have to be in the list. If it
+ isn't then this is a no-op
+*/
#define DLIST_REMOVE(list, p) \
do { \
if ((p) == (list)) { \
+ if ((p)->next) (p)->next->prev = (p)->prev; \
(list) = (p)->next; \
- if (list) (list)->prev = NULL; \
+ } else if ((list) && (p) == (list)->prev) { \
+ (p)->prev->next = NULL; \
+ (list)->prev = (p)->prev; \
} else { \
if ((p)->prev) (p)->prev->next = (p)->next; \
if ((p)->next) (p)->next->prev = (p)->prev; \
} \
- if ((p) != (list)) (p)->next = (p)->prev = NULL; \
+ if ((p) != (list)) (p)->next = (p)->prev = NULL; \
} while (0)
-/* promote an element to the top of the list */
-#define DLIST_PROMOTE(list, p) \
+/*
+ find the head of the list given any element in it.
+ Note that this costs O(N), so you should avoid this macro
+ if at all possible!
+*/
+#define DLIST_HEAD(p, result_head) \
do { \
- DLIST_REMOVE(list, p); \
- DLIST_ADD(list, p); \
-} while (0)
+ (result_head) = (p); \
+ while (DLIST_PREV(result_head)) (result_head) = (result_head)->prev; \
+} while(0)
-/* hook into the end of the list - needs a tmp pointer */
-#define DLIST_ADD_END(list, p, type) \
-do { \
- if (!(list)) { \
- (list) = (p); \
- (p)->next = (p)->prev = NULL; \
- } else { \
- type tmp; \
- for (tmp = (list); tmp->next; tmp = tmp->next) ; \
- tmp->next = (p); \
- (p)->next = NULL; \
- (p)->prev = tmp; \
- } \
-} while (0)
+/* return the last element in the list */
+#define DLIST_TAIL(list) ((list)?(list)->prev:NULL)
+
+/* return the previous element in the list. */
+#define DLIST_PREV(p) (((p)->prev && (p)->prev->next != NULL)?(p)->prev:NULL)
/* insert 'p' after the given element 'el' in a list. If el is NULL then
this is the same as a DLIST_ADD() */
@@ -80,80 +120,62 @@ do { \
if (!(list) || !(el)) { \
DLIST_ADD(list, p); \
} else { \
- p->prev = el; \
- p->next = el->next; \
- el->next = p; \
- if (p->next) p->next->prev = p; \
+ (p)->prev = (el); \
+ (p)->next = (el)->next; \
+ (el)->next = (p); \
+ if ((p)->next) (p)->next->prev = (p); \
+ if ((list)->prev == (el)) (list)->prev = (p); \
}\
} while (0)
-/* demote an element to the end of the list, needs a tmp pointer */
-#define DLIST_DEMOTE(list, p, tmp) \
+
+/*
+ add to the end of a list.
+ Note that 'type' is ignored
+*/
+#define DLIST_ADD_END(list, p, type) \
do { \
- DLIST_REMOVE(list, p); \
- DLIST_ADD_END(list, p, tmp); \
+ if (!(list)) { \
+ DLIST_ADD(list, p); \
+ } else { \
+ DLIST_ADD_AFTER(list, p, (list)->prev); \
+ } \
} while (0)
-/* concatenate two lists - putting all elements of the 2nd list at the
- end of the first list */
-#define DLIST_CONCATENATE(list1, list2, type) \
+/* promote an element to the from of a list */
+#define DLIST_PROMOTE(list, p) \
do { \
- if (!(list1)) { \
- (list1) = (list2); \
- } else { \
- type tmp; \
- for (tmp = (list1); tmp->next; tmp = tmp->next) ; \
- tmp->next = (list2); \
- if (list2) { \
- (list2)->prev = tmp; \
- } \
- } \
+ DLIST_REMOVE(list, p); \
+ DLIST_ADD(list, p); \
} while (0)
/*
- The TLIST_*() macros are meant for when you have two list pointers,
- one pointing at the head of the list and one pointing at the tail
- of the list. This makes the common case of adding to the end of the
- list and removing from the front of the list efficient
-
- TLIST stands for "tailed list"
-
- Note: When initialising the structure containing your lists, make
- sure that you set both head and tail to NULL
-
- Also, do not mix the TLIST_*() macros with the DLIST_* macros!
+ demote an element to the end of a list.
+ Note that 'type' is ignored
*/
-
-/* TLIST_ADD_FRONT adds elements to the front of the list. */
-#define TLIST_ADD_FRONT(listhead, listtail, p) \
+#define DLIST_DEMOTE(list, p, type) \
do { \
- DLIST_ADD(listhead, p); \
- if (NULL == (listtail)) { \
- (listtail) = (p); \
- } \
+ DLIST_REMOVE(list, p); \
+ DLIST_ADD_END(list, p, NULL); \
} while (0)
-/* TLIST_ADD_END adds elements to the end of the list. */
-#define TLIST_ADD_END(listhead, listtail, p) \
+/*
+ concatenate two lists - putting all elements of the 2nd list at the
+ end of the first list.
+ Note that 'type' is ignored
+*/
+#define DLIST_CONCATENATE(list1, list2, type) \
do { \
- if ((listtail) == NULL) { \
- DLIST_ADD(listhead, p); \
- (listtail) = (listhead); \
+ if (!(list1)) { \
+ (list1) = (list2); \
} else { \
- (listtail)->next = (p); \
- (p)->prev = (listtail); \
- (p)->next = NULL; \
- (listtail) = (p); \
- } \
-} while (0)
-
-/* TLIST_REMOVE removes an element from the list */
-#define TLIST_REMOVE(listhead, listtail, p) \
-do { \
- if ((p) == (listtail)) { \
- (listtail) = (p)->prev; \
+ (list1)->prev->next = (list2); \
+ if (list2) { \
+ void *_tmplist = (void *)(list1)->prev; \
+ (list1)->prev = (list2)->prev; \
+ (list2)->prev = _tmplist; \
+ } \
} \
- DLIST_REMOVE(listhead, p); \
} while (0)
#endif /* _DLINKLIST_H */
--
CTDB repository
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