Return to IOBufferMemoryDescriptor.h CVS log

Up to [Apple XNU] / XNU / iokit / IOKit

Annotation of XNU/iokit/IOKit/IOBufferMemoryDescriptor.h, revision 1.1

1.1     ! root        1: /*
        !             2:  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
        !             3:  *
        !             4:  * @APPLE_LICENSE_HEADER_START@
        !             5:  * 
        !             6:  * The contents of this file constitute Original Code as defined in and
        !             7:  * are subject to the Apple Public Source License Version 1.1 (the
        !             8:  * "License").  You may not use this file except in compliance with the
        !             9:  * License.  Please obtain a copy of the License at
        !            10:  * http://www.apple.com/publicsource and read it before using this file.
        !            11:  * 
        !            12:  * This Original Code and all software distributed under the License are
        !            13:  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
        !            14:  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
        !            15:  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
        !            16:  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
        !            17:  * License for the specific language governing rights and limitations
        !            18:  * under the License.
        !            19:  * 
        !            20:  * @APPLE_LICENSE_HEADER_END@
        !            21:  */
        !            22: #ifndef _IOBUFFERMEMORYDESCRIPTOR_H
        !            23: #define _IOBUFFERMEMORYDESCRIPTOR_H
        !            24: 
        !            25: #include <IOKit/IOMemoryDescriptor.h>
        !            26: 
        !            27: class IOBufferMemoryDescriptor : public IOGeneralMemoryDescriptor
        !            28: {
        !            29:     OSDeclareDefaultStructors(IOBufferMemoryDescriptor);
        !            30: 
        !            31: protected:
        !            32:     void *               _buffer;
        !            33:     vm_size_t            _capacity;
        !            34:     bool                 _contiguous;
        !            35:     IOPhysicalAddress *  _physAddrs;
        !            36:     unsigned             _physSegCount;
        !            37: 
        !            38:     virtual void free();
        !            39: 
        !            40:     IOGeneralMemoryDescriptor::initWithAddress;  /* not supported in subclass */
        !            41:     IOGeneralMemoryDescriptor::withAddress;      /* not supported in subclass */
        !            42:     IOGeneralMemoryDescriptor::initWithRanges;   /* not supported in subclass */
        !            43:     IOGeneralMemoryDescriptor::withRanges;       /* not supported in subclass */
        !            44: 
        !            45: public:
        !            46: 
        !            47:     /*
        !            48:      * initWithCapacity:
        !            49:      *
        !            50:      * Initialize a new IOBufferMemoryDescriptor with a buffer large enough to
        !            51:      * hold capacity bytes.  The descriptor's length is initially set to zero.
        !            52:      */
        !            53:     virtual bool initWithCapacity(vm_size_t   capacity,
        !            54:                                   IODirection withDirection,
        !            55:                                   bool        withContiguousMemory = false);
        !            56: 
        !            57:     /*
        !            58:      * withCapacity:
        !            59:      *
        !            60:      * Returns a new IOBufferMemoryDescriptor with a buffer large enough to
        !            61:      * hold capacity bytes.  The descriptor's length is initially set to zero.
        !            62:      */
        !            63:     static IOBufferMemoryDescriptor * withCapacity(
        !            64:                                      vm_size_t    capacity,
        !            65:                                      IODirection  withDirection,
        !            66:                                      bool         withContiguousMemory = false);
        !            67:     /*
        !            68:      * initWithBytes:
        !            69:      *
        !            70:      * Initialize a new IOBufferMemoryDescriptor preloaded with bytes (copied).
        !            71:      * The descriptor's length and capacity are set to the input buffer's size.
        !            72:      */
        !            73:     virtual bool initWithBytes(const void * bytes,
        !            74:                                vm_size_t    withLength,
        !            75:                                IODirection  withDirection,
        !            76:                                bool         withContiguousMemory = false);
        !            77: 
        !            78:     /*
        !            79:      * withBytes:
        !            80:      *
        !            81:      * Returns a new IOBufferMemoryDescriptor preloaded with bytes (copied).
        !            82:      * The descriptor's length and capacity are set to the input buffer's size.
        !            83:      */
        !            84:     static IOBufferMemoryDescriptor * withBytes(
        !            85:                                      const void * bytes,
        !            86:                                      vm_size_t    withLength,
        !            87:                                      IODirection  withDirection,
        !            88:                                      bool         withContiguousMemory = false);
        !            89: 
        !            90:     /*
        !            91:      * setLength:
        !            92:      *
        !            93:      * Change the buffer length of the memory descriptor.  When a new buffer is
        !            94:      * created with initWithBytes, the descriptor's length is set to capacity,
        !            95:      * or its length is initially zero.  This method allows one to resize the
        !            96:      * buffer length up to capacity or less.  This eliminates the need to
        !            97:      * destroy and create new buffers when different sizes are needed.  The
        !            98:      * descriptor position is implicitly reset to zero as a result of this call.
        !            99:      */
        !           100:     virtual void setLength(vm_size_t length);
        !           101: 
        !           102:     /*
        !           103:      * setDirection:
        !           104:      *
        !           105:      * Change the direction of the transfer.  This method allows one to redirect
        !           106:      * the descriptor's transfer direction.  This eliminates the need to destroy
        !           107:      * and create new buffers when different transfer directions are needed.
        !           108:      */
        !           109:     virtual void setDirection(IODirection direction);
        !           110: 
        !           111:     /*
        !           112:      * getCapacity:
        !           113:      *
        !           114:      * Get the buffer capacity
        !           115:      */
        !           116:     virtual vm_size_t getCapacity() const;
        !           117: 
        !           118:     /*
        !           119:      * getBytesNoCopy:
        !           120:      *
        !           121:      * Return the virtual address of the beginning of the buffer
        !           122:      */
        !           123:     virtual void *getBytesNoCopy();
        !           124: 
        !           125:     /*
        !           126:      * getBytesNoCopy:
        !           127:      *
        !           128:      * Return the virtual address of an offset from the beginning of the buffer
        !           129:      */
        !           130:     virtual void *getBytesNoCopy(vm_size_t start, vm_size_t withLength);
        !           131: 
        !           132:     /*
        !           133:      * appendBytes:
        !           134:      *
        !           135:      * Add some data to the end of the buffer.  This method automatically
        !           136:      * maintains the memory descriptor buffer length.  Note that appendBytes
        !           137:      * will not copy past the end of the memory descriptor's current capacity.
        !           138:      */
        !           139:     virtual bool appendBytes(const void *bytes, vm_size_t withLength);
        !           140: 
        !           141:     /*
        !           142:      * getPhysicalSegment:
        !           143:      *
        !           144:      * Get the physical address of the buffer, relative to the current position.
        !           145:      * If the current position is at the end of the buffer, a zero is returned.
        !           146:      */
        !           147:     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
        !           148:                                                 IOPhysicalLength * length);    
        !           149: };
        !           150: 
        !           151: #endif /* !_IOBUFFERMEMORYDESCRIPTOR_H */

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.