--- /dev/null
+/*
+ * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+#include <IOKit/IOSharedDataQueue.h>
+#include <IOKit/IODataQueueShared.h>
+#include <IOKit/IOLib.h>
+#include <IOKit/IOMemoryDescriptor.h>
+
+#ifdef dequeue
+#undef dequeue
+#endif
+
+#define super IODataQueue
+
+OSDefineMetaClassAndStructors(IOSharedDataQueue, IODataQueue)
+
+IOSharedDataQueue *IOSharedDataQueue::withCapacity(UInt32 size)
+{
+ IOSharedDataQueue *dataQueue = new IOSharedDataQueue;
+
+ if (dataQueue) {
+ if (!dataQueue->initWithCapacity(size)) {
+ dataQueue->release();
+ dataQueue = 0;
+ }
+ }
+
+ return dataQueue;
+}
+
+IOSharedDataQueue *IOSharedDataQueue::withEntries(UInt32 numEntries, UInt32 entrySize)
+{
+ IOSharedDataQueue *dataQueue = new IOSharedDataQueue;
+
+ if (dataQueue) {
+ if (!dataQueue->initWithEntries(numEntries, entrySize)) {
+ dataQueue->release();
+ dataQueue = 0;
+ }
+ }
+
+ return dataQueue;
+}
+
+Boolean IOSharedDataQueue::initWithCapacity(UInt32 size)
+{
+ IODataQueueAppendix * appendix;
+
+ if (!super::init()) {
+ return false;
+ }
+
+ dataQueue = (IODataQueueMemory *)IOMallocAligned(round_page_32(size + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE), PAGE_SIZE);
+ if (dataQueue == 0) {
+ return false;
+ }
+
+ dataQueue->queueSize = size;
+ dataQueue->head = 0;
+ dataQueue->tail = 0;
+
+ appendix = (IODataQueueAppendix *)((UInt8 *)dataQueue + size + DATA_QUEUE_MEMORY_HEADER_SIZE);
+ appendix->version = 0;
+ notifyMsg = &(appendix->msgh);
+ setNotificationPort(MACH_PORT_NULL);
+
+ return true;
+}
+
+void IOSharedDataQueue::free()
+{
+ if (dataQueue) {
+ IOFreeAligned(dataQueue, round_page_32(dataQueue->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE));
+ dataQueue = NULL;
+ }
+
+ super::free();
+}
+
+IOMemoryDescriptor *IOSharedDataQueue::getMemoryDescriptor()
+{
+ IOMemoryDescriptor *descriptor = 0;
+
+ if (dataQueue != 0) {
+ descriptor = IOMemoryDescriptor::withAddress(dataQueue, dataQueue->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE, kIODirectionOutIn);
+ }
+
+ return descriptor;
+}
+
+
+IODataQueueEntry * IOSharedDataQueue::peek()
+{
+ IODataQueueEntry *entry = 0;
+
+ if (dataQueue && (dataQueue->head != dataQueue->tail)) {
+ IODataQueueEntry * head = 0;
+ UInt32 headSize = 0;
+ UInt32 headOffset = dataQueue->head;
+ UInt32 queueSize = dataQueue->queueSize;
+
+ head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
+ headSize = head->size;
+
+ // Check if there's enough room before the end of the queue for a header.
+ // If there is room, check if there's enough room to hold the header and
+ // the data.
+
+ if ((headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
+ ((headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE) > queueSize))
+ {
+ // No room for the header or the data, wrap to the beginning of the queue.
+ entry = dataQueue->queue;
+ } else {
+ entry = head;
+ }
+ }
+
+ return entry;
+}
+
+Boolean IOSharedDataQueue::dequeue(void *data, UInt32 *dataSize)
+{
+ Boolean retVal = TRUE;
+ IODataQueueEntry * entry = 0;
+ UInt32 entrySize = 0;
+ UInt32 newHeadOffset = 0;
+
+ if (dataQueue) {
+ if (dataQueue->head != dataQueue->tail) {
+ IODataQueueEntry * head = 0;
+ UInt32 headSize = 0;
+ UInt32 headOffset = dataQueue->head;
+ UInt32 queueSize = dataQueue->queueSize;
+
+ head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
+ headSize = head->size;
+
+ // we wraped around to beginning, so read from there
+ // either there was not even room for the header
+ if ((headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
+ // or there was room for the header, but not for the data
+ ((headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE) > queueSize)) {
+ entry = dataQueue->queue;
+ entrySize = entry->size;
+ newHeadOffset = entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
+ // else it is at the end
+ } else {
+ entry = head;
+ entrySize = entry->size;
+ newHeadOffset = headOffset + entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
+ }
+ }
+
+ if (entry) {
+ if (data) {
+ if (dataSize) {
+ if (entrySize <= *dataSize) {
+ memcpy(data, &(entry->data), entrySize);
+ dataQueue->head = newHeadOffset;
+ } else {
+ retVal = FALSE;
+ }
+ } else {
+ retVal = FALSE;
+ }
+ } else {
+ dataQueue->head = newHeadOffset;
+ }
+
+ if (dataSize) {
+ *dataSize = entrySize;
+ }
+ } else {
+ retVal = FALSE;
+ }
+ } else {
+ retVal = FALSE;
+ }
+
+ return retVal;
+}
+
+
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 0);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 1);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 2);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 3);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 4);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 5);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 6);
+OSMetaClassDefineReservedUnused(IOSharedDataQueue, 7);
projects / apple / xnu.git / blobdiff