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--- xnu/xnu-3248.20.55/iokit/Kernel/IOSharedDataQueue.cpp
+++ /dev/null
@@ -1,385 +0,0 @@
-/*
- * 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 enqueue
-#undef enqueue
-#endif
-
-#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;
- vm_size_t allocSize;
-
- if (!super::init()) {
- return false;
- }
-
- _reserved = (ExpansionData *)IOMalloc(sizeof(struct ExpansionData));
- if (!_reserved) {
- return false;
- }
-
- if (size > UINT32_MAX - DATA_QUEUE_MEMORY_HEADER_SIZE - DATA_QUEUE_MEMORY_APPENDIX_SIZE) {
- return false;
- }
-
- allocSize = round_page(size + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE);
-
- if (allocSize < size) {
- return false;
- }
-
- dataQueue = (IODataQueueMemory *)IOMallocAligned(allocSize, PAGE_SIZE);
- if (dataQueue == 0) {
- return false;
- }
- bzero(dataQueue, allocSize);
-
- dataQueue->queueSize = size;
-// dataQueue->head = 0;
-// dataQueue->tail = 0;
-
- if (!setQueueSize(size)) {
- return false;
- }
-
- appendix = (IODataQueueAppendix *)((UInt8 *)dataQueue + size + DATA_QUEUE_MEMORY_HEADER_SIZE);
- appendix->version = 0;
-
- if (!notifyMsg) {
- notifyMsg = IOMalloc(sizeof(mach_msg_header_t));
- if (!notifyMsg)
- return false;
- }
- bzero(notifyMsg, sizeof(mach_msg_header_t));
-
- setNotificationPort(MACH_PORT_NULL);
-
- return true;
-}
-
-void IOSharedDataQueue::free()
-{
- if (dataQueue) {
- IOFreeAligned(dataQueue, round_page(getQueueSize() + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE));
- dataQueue = NULL;
- if (notifyMsg) {
- IOFree(notifyMsg, sizeof(mach_msg_header_t));
- notifyMsg = NULL;
- }
- }
-
- if (_reserved) {
- IOFree (_reserved, sizeof(struct ExpansionData));
- _reserved = NULL;
- }
-
- super::free();
-}
-
-IOMemoryDescriptor *IOSharedDataQueue::getMemoryDescriptor()
-{
- IOMemoryDescriptor *descriptor = 0;
-
- if (dataQueue != 0) {
- descriptor = IOMemoryDescriptor::withAddress(dataQueue, getQueueSize() + 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 = getQueueSize();
-
- if (headOffset >= queueSize) {
- return NULL;
- }
-
- 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 > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX - headSize) ||
- (headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize)) {
- // No room for the header or the data, wrap to the beginning of the queue.
- // Note: wrapping even with the UINT32_MAX checks, as we have to support
- // queueSize of UINT32_MAX
- entry = dataQueue->queue;
- } else {
- entry = head;
- }
- }
-
- return entry;
-}
-
-Boolean IOSharedDataQueue::enqueue(void * data, UInt32 dataSize)
-{
- const UInt32 head = dataQueue->head; // volatile
- const UInt32 tail = dataQueue->tail;
- const UInt32 entrySize = dataSize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- IODataQueueEntry * entry;
-
- // Check for overflow of entrySize
- if (dataSize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) {
- return false;
- }
- // Check for underflow of (getQueueSize() - tail)
- if (getQueueSize() < tail || getQueueSize() < head) {
- return false;
- }
-
- if ( tail >= head )
- {
- // Is there enough room at the end for the entry?
- if ((entrySize <= UINT32_MAX - tail) &&
- ((tail + entrySize) <= getQueueSize()) )
- {
- entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
-
- entry->size = dataSize;
- memcpy(&entry->data, data, dataSize);
-
- // The tail can be out of bound when the size of the new entry
- // exactly matches the available space at the end of the queue.
- // The tail can range from 0 to dataQueue->queueSize inclusive.
-
- OSAddAtomic(entrySize, (SInt32 *)&dataQueue->tail);
- }
- else if ( head > entrySize ) // Is there enough room at the beginning?
- {
- // Wrap around to the beginning, but do not allow the tail to catch
- // up to the head.
-
- dataQueue->queue->size = dataSize;
-
- // We need to make sure that there is enough room to set the size before
- // doing this. The user client checks for this and will look for the size
- // at the beginning if there isn't room for it at the end.
-
- if ( ( getQueueSize() - tail ) >= DATA_QUEUE_ENTRY_HEADER_SIZE )
- {
- ((IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail))->size = dataSize;
- }
-
- memcpy(&dataQueue->queue->data, data, dataSize);
- OSCompareAndSwap(dataQueue->tail, entrySize, &dataQueue->tail);
- }
- else
- {
- return false; // queue is full
- }
- }
- else
- {
- // Do not allow the tail to catch up to the head when the queue is full.
- // That's why the comparison uses a '>' rather than '>='.
-
- if ( (head - tail) > entrySize )
- {
- entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
-
- entry->size = dataSize;
- memcpy(&entry->data, data, dataSize);
- OSAddAtomic(entrySize, (SInt32 *)&dataQueue->tail);
- }
- else
- {
- return false; // queue is full
- }
- }
-
- // Send notification (via mach message) that data is available.
-
- if ( ( head == tail ) /* queue was empty prior to enqueue() */
- || ( dataQueue->head == tail ) ) /* queue was emptied during enqueue() */
- {
- sendDataAvailableNotification();
- }
-
- return true;
-}
-
-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 = getQueueSize();
-
- if (headOffset > queueSize) {
- return false;
- }
-
- head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
- headSize = head->size;
-
- // we wrapped around to beginning, so read from there
- // either there was not even room for the header
- if ((headOffset > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
- // or there was room for the header, but not for the data
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX - headSize) ||
- (headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize)) {
- // Note: we have to wrap to the beginning even with the UINT32_MAX checks
- // because we have to support a queueSize of UINT32_MAX.
- entry = dataQueue->queue;
- entrySize = entry->size;
- if ((entrySize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize)) {
- return false;
- }
- newHeadOffset = entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- // else it is at the end
- } else {
- entry = head;
- entrySize = entry->size;
- if ((entrySize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX - headOffset) ||
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE + headOffset > queueSize)) {
- return false;
- }
- newHeadOffset = headOffset + entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- }
- }
-
- if (entry) {
- if (data) {
- if (dataSize) {
- if (entrySize <= *dataSize) {
- memcpy(data, &(entry->data), entrySize);
- OSCompareAndSwap( dataQueue->head, newHeadOffset, (SInt32 *)&dataQueue->head);
- } else {
- retVal = FALSE;
- }
- } else {
- retVal = FALSE;
- }
- } else {
- OSCompareAndSwap( dataQueue->head, newHeadOffset, (SInt32 *)&dataQueue->head);
- }
-
- if (dataSize) {
- *dataSize = entrySize;
- }
- } else {
- retVal = FALSE;
- }
- } else {
- retVal = FALSE;
- }
-
- return retVal;
-}
-
-UInt32 IOSharedDataQueue::getQueueSize()
-{
- if (!_reserved) {
- return 0;
- }
- return _reserved->queueSize;
-}
-
-Boolean IOSharedDataQueue::setQueueSize(UInt32 size)
-{
- if (!_reserved) {
- return false;
- }
- _reserved->queueSize = size;
- return true;
-}
-
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 0);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 1);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 2);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 3);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 4);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 5);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 6);
-OSMetaClassDefineReservedUnused(IOSharedDataQueue, 7);