From 878679fa3f78d69042c9a56977b3d032791b7a47 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Mon, 28 Mar 2016 02:14:54 +0200
Subject: added missing file
---
lib/pure/collections/sharedlist.nim | 95 +++++++++++++++++++++++++++++++++++++
1 file changed, 95 insertions(+)
create mode 100644 lib/pure/collections/sharedlist.nim
(limited to 'lib/pure/collections/sharedlist.nim')
diff --git a/lib/pure/collections/sharedlist.nim b/lib/pure/collections/sharedlist.nim
new file mode 100644
index 000000000..e93ceb02f
--- /dev/null
+++ b/lib/pure/collections/sharedlist.nim
@@ -0,0 +1,95 @@
+#
+#
+# Nim's Runtime Library
+# (c) Copyright 2015 Andreas Rumpf
+#
+# See the file "copying.txt", included in this
+# distribution, for details about the copyright.
+#
+
+## Shared list support.
+
+{.push stackTrace:off.}
+
+import
+ locks
+
+const
+ ElemsPerNode = 100
+
+type
+ SharedListNode[A] = ptr object
+ next: SharedListNode[A]
+ dataLen: int
+ d: array[ElemsPerNode, A]
+
+ SharedList*[A] = object ## generic shared list
+ head, tail: SharedListNode[A]
+ lock*: Lock
+
+template withLock(t, x: untyped) =
+ acquire(t.lock)
+ x
+ release(t.lock)
+
+proc iterAndMutate*[A](x: var SharedList[A]; action: proc(x: A): bool) =
+ ## iterates over the list. If 'action' returns true, the
+ ## current item is removed from the list.
+ withLock(x):
+ var n = x.head
+ while n != nil:
+ var i = 0
+ while i < n.dataLen:
+ # action can add new items at the end, so release the lock:
+ release(x.lock)
+ if action(n.d[i]):
+ acquire(x.lock)
+ let t = x.tail
+ n.d[i] = t.d[t.dataLen]
+ dec t.dataLen
+ else:
+ acquire(x.lock)
+ inc i
+ n = n.next
+
+iterator items*[A](x: var SharedList[A]): A =
+ withLock(x):
+ var it = x.head
+ while it != nil:
+ for i in 0..it.dataLen-1:
+ yield it.d[i]
+ it = it.next
+
+proc add*[A](x: var SharedList[A]; y: A) =
+ withLock(x):
+ var node: SharedListNode[A]
+ if x.tail == nil or x.tail.dataLen == ElemsPerNode:
+ node = cast[type node](allocShared0(sizeof(node[])))
+ node.next = x.tail
+ x.tail = node
+ if x.head == nil: x.head = node
+ else:
+ node = x.tail
+ node.d[node.dataLen] = y
+ inc(node.dataLen)
+
+proc initSharedList*[A](): SharedList[A] =
+ initLock result.lock
+ result.head = nil
+ result.tail = nil
+
+proc clear*[A](t: var SharedList[A]) =
+ withLock(t):
+ var it = t.head
+ while it != nil:
+ let nxt = it.next
+ deallocShared(it)
+ it = nxt
+ t.head = nil
+ t.tail = nil
+
+proc deinitSharedList*[A](t: var SharedList[A]) =
+ clear(t)
+ deinitLock t.lock
+
+{.pop.}
--
cgit 1.4.1-2-gfad0