binding-cpp/runtime/include/transport/EtchFlexBuffer.h - etch - Git at Google

 /* $Id$
  *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements. See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to you under the Apache License, Version
  * 2.0 (the "License"); you may not use this file except in compliance
  * with the License. You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #ifndef __ETCHFLEXBUFFER_H__
 #define __ETCHFLEXBUFFER_H__

 #include "capu/util/SmartPointer.h"
 #include "common/EtchConfig.h"
 #include "common/EtchError.h"
 #include "transport/EtchByteRepresentation.h"

 /**
  * A FlexBuffer wraps a byte array and manages the active region of
  * it (0..length). It also supports dynamically extending the buffer
  * as needed.
  *
  * A FlexBuffer also has an index (read or write cursor). The various
  * get and put operations always occur at the current index, with the
  * index adjusted appropriately afterward. Get will not move index past
  * length. If put needs to move index past length, length is also
  * adjusted. This may cause the byte array to be re-allocated to a
  * larger size.
  */

 class EtchFlexBuffer {
 public:

   /**
    * Constructs a FlexBuffer with internal buffer and index and length of 0.
    */
   EtchFlexBuffer();

   /**
    * Constructs a FlexBuffer with internal buffer and index and length of 0.
    */
   EtchFlexBuffer(capu::int8_t *buf, capu::uint32_t size);

   /**
    * Destructor a FlexBuffer with internal buffer and index and length of 0.
    */
   ~EtchFlexBuffer();

   /**
    * @return the current byte array. Might change if any operation
    * needs to extend length past the end of the array.
    */
   capu::int8_t * getBuffer();

   /**
    * @return the current value of length. This is the last
    * index of valid data in the buffer.
    */
   capu::uint32_t getLength();

   /**
    * @return the current size of the buffer
    *
    */
   capu::uint32_t getSize();

   /**
    * @return the current value of index.
    */
   capu::uint32_t getIndex();

   /**
    * @return length() - index(). This is the amount
    * of data that could be read using the various forms of get. It doesn't
    * really mean anything in relation to put.
    */
   capu::uint32_t getAvailableBytes();

   /**
    * gets an integer value from flexible buffer
    * @param an int composed from the next 4 bytes. Little-endian.
    * @return ETCH_OK if an integer successfully read
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
    */
   status_t getInteger(capu::uint32_t & value);

   /**
    * gets an byte value from flexible buffer
    * @param an char composed from the next 1 bytes.
    * @return ETCH_OK if an integer successfully read
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
    */
   status_t getByte(capu::int8_t & value);


   /**
    * gets an short value from flexible buffer
    * @param an short composed from the next 2 bytes. Little-endian.
    * @return ETCH_OK if an integer successfully read
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
    */
   status_t getShort(capu::int16_t & value);


   /**
    * gets an long value from flexible buffer
    * @param an long composed from the next 8 bytes. Little-endian.
    * @return ETCH_OK if an integer successfully read
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
    */
   status_t getLong(capu::int64_t & value);

   /**
    * gets an float value from flexible buffer
    * @param an float composed from the next 2 bytes. Little-endian.
    * @return ETCH_OK if an integer successfully read
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
    */
   status_t getFloat(capu::float_t & value);


   /**
    * gets an double value from flexible buffer
    * @param an double composed from the next 8 bytes. Little-endian.
    * @return ETCH_OK if an integer successfully read
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
    */
   status_t getDouble(capu::double_t & value);


   /**
    * Sets the index
    *
    * @param index the new value of index.
    * @return ETCH_OK if the index is successfully set
    *         ETCH_EINVAL if the given index is not valid
    *
    */
   status_t setIndex(capu::uint32_t index);

   /**
    * Sets the length of flexbuffer
    *
    * @param index the new value of index.
    * @return ETCH_OK if the length is successfully set
    *         ETCH_ENO_MEMORY if the buffer with given size can not be allocated
    *
    */
   status_t setLength(capu::uint32_t length);

   /**
    * Sets both index and length to 0. Trims the buffer length if it is past
    * the recommended limit.
    *
    */
   void reset();

   /**
    * Copies the available bytes from buffer into mBuffer as if by
    * repeated execution of put( buf.get() ).
    * @param buffer the source of the bytes to put. All available
    * bytes are copied.
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_EINVAL if the buffer has inconsistency within their internals
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t put(EtchFlexBuffer & buffer);

   /**
    * Copies the available bytes from buf into buffer as if by
    * repeated execution of put( buf.get() ).
    * @param buffer the source of the bytes to put. All available
    * bytes are copied.
    * @param numBytes number of byte that will be copied
    *
    * @return ETCH_OK if the buf is put into the this flexbuffer
    *         ETCH_EINVAL if the buf has inconsistency within their internals
    *         ETCH_ERANGE if the buf's size is less than its index
    *
    */
   status_t put(EtchFlexBuffer & buffer, capu::uint32_t numBytes);

   /**
    * Copies the available bytes from buf into buffer as if by
    * repeated execution of put( buf.get() ).
    * @param buf the source of the bytes to put. All available
    * bytes are copied.
    * @param  size number of bytes that will be copied
    *
    * @return ETCH_OK if the buf is put into the this flexbuffer
    *         ETCH_EINVAL if the buf has inconsistency within their internals
    *         ETCH_ERANGE if the buf's size is less than its index
    *
    */
   status_t put(capu::int8_t *buffer, capu::uint32_t numBytes);

   /**
    * Copies a byte to flex buffer
    * @param value that will be copied
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t putByte(capu::int8_t value);

   /**
    * Copies a short to flex buffer
    * @param value that will be copied
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t putShort(capu::int16_t value);

   /**
    * Copies a long to flex buffer
    * @param value that will be copied
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t putLong(capu::int64_t value);

   /**
    * Copies a int to flex buffer
    * @param value that will be copied
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t putInt(capu::int32_t value);

   /**
    * Copies a float to flex buffer
    * @param value that will be copied
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t putFloat(capu::float_t value);

   /**
    * Copies a double to flex buffer
    * @param value that will be copied
    * @return ETCH_OK if the buffer is put into the this
    *         ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
    *         ETCH_ERANGE if the buffer's size is less than its index
    *
    */
   status_t putDouble(capu::double_t value);

   /**
    * @param value is a boolean value to specify LittleEndian or BigEndian representation
    *        ETCH_LITTLE_ENDIAN for LittleEndian
    *        ETCH_BIG_ENDIAN for BigEndian
    */
   void setByteRepresentation(EtchByteRepresentation value);

   /**
    * @return ETCH_LITTLE_ENDIAN for LittleEndian
    *         ETCH_BIG_ENDIAN for BigEndian
    */
   EtchByteRepresentation getByteRepresentation();

   /**
    * Copies data from the byte array to buf as if by repeated
    * calls to getByte().
    * @param buf a buffer to receive the data. At most
    * min( mLength, getAvailableBytes() ) bytes are transferred, starting
    * at off.
    * @param off the index in buf to receive the data.
    * off must be <= buf.length.
    *
    * @param len, length of buffer
    * @param numBytes contains the amount of data which has been copied to buf. 0 if there occured an error.
    *
    * @return ETCH_OK  data is successfully transferred.
    *         ETCH_EINVAL if buffer is null or len is 0
    */
   status_t get(capu::int8_t *buf, capu::uint32_t off, capu::uint32_t len, capu::uint32_t& numBytes);

 private:

   const capu::uint32_t INIT_BUFFER_LEN;

   const capu::uint32_t MAX_BUFFER_LEN;

   const capu::uint32_t TRIM_BUFFER_LEN;

   capu::int8_t *mBuffer;

   capu::uint32_t mSize;

   capu::uint32_t mIndex;

   capu::uint32_t mLength;

   EtchByteRepresentation mByteRepresentation;

   status_t expandBuffer(capu::uint32_t numBytes);

   status_t checkBuffer(EtchFlexBuffer & buffer, capu::uint32_t numBytes);

   void copy(capu::int8_t *buffer, capu::uint32_t numBytes);
 };

 typedef capu::SmartPointer<EtchFlexBuffer> EtchFlexBufferPtr;

 #endif /* ETCHFLEXBUFFER_H */
	/* $Id$
	*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to you under the Apache License, Version
	* 2.0 (the "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#ifndef __ETCHFLEXBUFFER_H__
	#define __ETCHFLEXBUFFER_H__

	#include "capu/util/SmartPointer.h"
	#include "common/EtchConfig.h"
	#include "common/EtchError.h"
	#include "transport/EtchByteRepresentation.h"

	/**
	* A FlexBuffer wraps a byte array and manages the active region of
	* it (0..length). It also supports dynamically extending the buffer
	* as needed.
	*
	* A FlexBuffer also has an index (read or write cursor). The various
	* get and put operations always occur at the current index, with the
	* index adjusted appropriately afterward. Get will not move index past
	* length. If put needs to move index past length, length is also
	* adjusted. This may cause the byte array to be re-allocated to a
	* larger size.
	*/

	class EtchFlexBuffer {
	public:

	/**
	* Constructs a FlexBuffer with internal buffer and index and length of 0.
	*/
	EtchFlexBuffer();

	/**
	* Constructs a FlexBuffer with internal buffer and index and length of 0.
	*/
	EtchFlexBuffer(capu::int8_t *buf, capu::uint32_t size);

	/**
	* Destructor a FlexBuffer with internal buffer and index and length of 0.
	*/
	~EtchFlexBuffer();

	/**
	* @return the current byte array. Might change if any operation
	* needs to extend length past the end of the array.
	*/
	capu::int8_t * getBuffer();

	/**
	* @return the current value of length. This is the last
	* index of valid data in the buffer.
	*/
	capu::uint32_t getLength();

	/**
	* @return the current size of the buffer
	*
	*/
	capu::uint32_t getSize();

	/**
	* @return the current value of index.
	*/
	capu::uint32_t getIndex();

	/**
	* @return length() - index(). This is the amount
	* of data that could be read using the various forms of get. It doesn't
	* really mean anything in relation to put.
	*/
	capu::uint32_t getAvailableBytes();

	/**
	* gets an integer value from flexible buffer
	* @param an int composed from the next 4 bytes. Little-endian.
	* @return ETCH_OK if an integer successfully read
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
	*/
	status_t getInteger(capu::uint32_t & value);

	/**
	* gets an byte value from flexible buffer
	* @param an char composed from the next 1 bytes.
	* @return ETCH_OK if an integer successfully read
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
	*/
	status_t getByte(capu::int8_t & value);


	/**
	* gets an short value from flexible buffer
	* @param an short composed from the next 2 bytes. Little-endian.
	* @return ETCH_OK if an integer successfully read
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
	*/
	status_t getShort(capu::int16_t & value);


	/**
	* gets an long value from flexible buffer
	* @param an long composed from the next 8 bytes. Little-endian.
	* @return ETCH_OK if an integer successfully read
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
	*/
	status_t getLong(capu::int64_t & value);

	/**
	* gets an float value from flexible buffer
	* @param an float composed from the next 2 bytes. Little-endian.
	* @return ETCH_OK if an integer successfully read
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
	*/
	status_t getFloat(capu::float_t & value);


	/**
	* gets an double value from flexible buffer
	* @param an double composed from the next 8 bytes. Little-endian.
	* @return ETCH_OK if an integer successfully read
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if there is not enough value to be read (less than 4 byte)
	*/
	status_t getDouble(capu::double_t & value);


	/**
	* Sets the index
	*
	* @param index the new value of index.
	* @return ETCH_OK if the index is successfully set
	* ETCH_EINVAL if the given index is not valid
	*
	*/
	status_t setIndex(capu::uint32_t index);

	/**
	* Sets the length of flexbuffer
	*
	* @param index the new value of index.
	* @return ETCH_OK if the length is successfully set
	* ETCH_ENO_MEMORY if the buffer with given size can not be allocated
	*
	*/
	status_t setLength(capu::uint32_t length);

	/**
	* Sets both index and length to 0. Trims the buffer length if it is past
	* the recommended limit.
	*
	*/
	void reset();

	/**
	* Copies the available bytes from buffer into mBuffer as if by
	* repeated execution of put( buf.get() ).
	* @param buffer the source of the bytes to put. All available
	* bytes are copied.
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_EINVAL if the buffer has inconsistency within their internals
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t put(EtchFlexBuffer & buffer);

	/**
	* Copies the available bytes from buf into buffer as if by
	* repeated execution of put( buf.get() ).
	* @param buffer the source of the bytes to put. All available
	* bytes are copied.
	* @param numBytes number of byte that will be copied
	*
	* @return ETCH_OK if the buf is put into the this flexbuffer
	* ETCH_EINVAL if the buf has inconsistency within their internals
	* ETCH_ERANGE if the buf's size is less than its index
	*
	*/
	status_t put(EtchFlexBuffer & buffer, capu::uint32_t numBytes);

	/**
	* Copies the available bytes from buf into buffer as if by
	* repeated execution of put( buf.get() ).
	* @param buf the source of the bytes to put. All available
	* bytes are copied.
	* @param size number of bytes that will be copied
	*
	* @return ETCH_OK if the buf is put into the this flexbuffer
	* ETCH_EINVAL if the buf has inconsistency within their internals
	* ETCH_ERANGE if the buf's size is less than its index
	*
	*/
	status_t put(capu::int8_t *buffer, capu::uint32_t numBytes);

	/**
	* Copies a byte to flex buffer
	* @param value that will be copied
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t putByte(capu::int8_t value);

	/**
	* Copies a short to flex buffer
	* @param value that will be copied
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t putShort(capu::int16_t value);

	/**
	* Copies a long to flex buffer
	* @param value that will be copied
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t putLong(capu::int64_t value);

	/**
	* Copies a int to flex buffer
	* @param value that will be copied
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t putInt(capu::int32_t value);

	/**
	* Copies a float to flex buffer
	* @param value that will be copied
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t putFloat(capu::float_t value);

	/**
	* Copies a double to flex buffer
	* @param value that will be copied
	* @return ETCH_OK if the buffer is put into the this
	* ETCH_EINVAL if the byte representation is not BIG ENDIAN or LITTLE ENDIAN
	* ETCH_ERANGE if the buffer's size is less than its index
	*
	*/
	status_t putDouble(capu::double_t value);

	/**
	* @param value is a boolean value to specify LittleEndian or BigEndian representation
	* ETCH_LITTLE_ENDIAN for LittleEndian
	* ETCH_BIG_ENDIAN for BigEndian
	*/
	void setByteRepresentation(EtchByteRepresentation value);

	/**
	* @return ETCH_LITTLE_ENDIAN for LittleEndian
	* ETCH_BIG_ENDIAN for BigEndian
	*/
	EtchByteRepresentation getByteRepresentation();

	/**
	* Copies data from the byte array to buf as if by repeated
	* calls to getByte().
	* @param buf a buffer to receive the data. At most
	* min( mLength, getAvailableBytes() ) bytes are transferred, starting
	* at off.
	* @param off the index in buf to receive the data.
	* off must be <= buf.length.
	*
	* @param len, length of buffer
	* @param numBytes contains the amount of data which has been copied to buf. 0 if there occured an error.
	*
	* @return ETCH_OK data is successfully transferred.
	* ETCH_EINVAL if buffer is null or len is 0
	*/
	status_t get(capu::int8_t *buf, capu::uint32_t off, capu::uint32_t len, capu::uint32_t& numBytes);

	private:

	const capu::uint32_t INIT_BUFFER_LEN;

	const capu::uint32_t MAX_BUFFER_LEN;

	const capu::uint32_t TRIM_BUFFER_LEN;

	capu::int8_t *mBuffer;

	capu::uint32_t mSize;

	capu::uint32_t mIndex;

	capu::uint32_t mLength;

	EtchByteRepresentation mByteRepresentation;

	status_t expandBuffer(capu::uint32_t numBytes);

	status_t checkBuffer(EtchFlexBuffer & buffer, capu::uint32_t numBytes);

	void copy(capu::int8_t *buffer, capu::uint32_t numBytes);
	};

	typedef capu::SmartPointer<EtchFlexBuffer> EtchFlexBufferPtr;

	#endif /* ETCHFLEXBUFFER_H */