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/*
* Copyright (c) 2017 Cisco and/or its affiliates.
* Licensed 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.
*/
/**
* @file parc_FileChunker.h
* @ingroup ContentObject
* @brief A FileChunker is a chunker that segments the content of a file.
*
*/
#ifndef libparc_parc_FileChunker_h
#define libparc_parc_FileChunker_h
#include <parc/algol/parc_Chunker.h>
#include <parc/algol/parc_File.h>
struct parc_buffer_chunker;
/**
* @typedef PARCFileChunker
* @brief The PARC Chunker
*/
typedef struct parc_buffer_chunker PARCFileChunker;
/**
* The mapping of a `PARCFileChunker` to the generic `PARCChunker`.
*/
extern PARCChunkerInterface *PARCFileChunkerAsChunker;
/**
* Create a new chunker to segment data contained in a `PARCBuffer.`
*
* @param [in] file A `PARCFile` from which the data will be read.
* @param [in] chunkSize The size per chunk.
*
* @retval PARCFileChunker A newly allocated `PARCFileChunker`
* @retval NULL An error occurred.
*
* Example
* @code
* {
* PARCBuffer *dataToChunk = ...
* PARCFileChunker *chunker = PARCFileChunker_CreateFromBuffer(dataToChunk, 32);
* }
*/
PARCFileChunker *parcFileChunker_Create(PARCFile *file, size_t chunkSize);
/**
* Increase the number of references to a `PARCFileChunker` instance.
*
* Note that new `PARCFileChunker` is not created,
* only that the given `PARCFileChunker` reference count is incremented.
* Discard the reference by invoking {@link PARCFileChunker_Release}.
*
* @param [in] chunker A pointer to the original `PARCFileChunker`.
* @return The value of the input parameter @p chunker.
*
* Example:
* @code
* {
* PARCFileChunker *original = parcFileChunker_Create(...);
*
* PARCFileChunker *reference = parcFileChunker_Acquire(original);
*
* parcFileChunker_Release(&original);
* parcFileChunker_Release(&reference);
* }
* @endcode
*
* @see parcFileChunker_Release
*/
PARCFileChunker *parcFileChunker_Acquire(const PARCFileChunker *chunker);
/**
* Release a previously acquired reference to the specified instance,
* decrementing the reference count for the instance.
*
* The pointer to the instance is set to NULL as a side-effect of this function.
*
* If the invocation causes the last reference to the instance to be released,
* the instance is deallocated and the instance's implementation will perform
* additional cleanup and release other privately held references.
*
* @param [in,out] chunkerP A pointer to a pointer to the instance to release.
*
*
* Example:
* @code
* {
* ...
*
* PARCFileChunker *chunker = parcFileChunker_Acquire(instance);
*
* parcFileChunker_Release(&chunker);
* }
* @endcode
*/
void parcFileChunker_Release(PARCFileChunker **chunkerP);
/**
* Determine if two `PARCFileChunker` instances are equal.
*
* The following equivalence relations on non-null `PARCFileChunker` instances are maintained:
*
* * It is reflexive: for any non-null reference value x, `parcFileChunker_Equals(x, x)`
* must return true.
*
* * It is symmetric: for any non-null reference values x and y,
* `parcFileChunker_Equals(x, y)` must return true if and only if
* `parcFileChunker_Equals(y, x)` returns true.
*
* * It is transitive: for any non-null reference values x, y, and z, if
* `parcFileChunker_Equals(x, y)` returns true and
* `parcFileChunker_Equals(y, z)` returns true,
* then `parcFileChunker_Equals(x, z)` must return true.
*
* * It is consistent: for any non-null reference values x and y, multiple
* invocations of `parcFileChunker_Equals(x, y)` consistently return true or
* consistently return false.
*
* * For any non-null reference value x, `parcFileChunker_Equals(x, NULL)` must
* return false.
*
* @param chunkerA A pointer to a `PARCFileChunker` instance.
* @param chunkerB A pointer to a `PARCFileChunker` instance.
* @return true if the two `PARCFileChunker` instances are equal.
*
* Example:
* @code
* {
* char *fileToChunk = ...
* PARCFileChunker *chunkerA = parcFileChunker_Create(fileToChunk, 32);
* PARCFileChunker *chunkerB = parcFileChunker_Create(fileToChunk, 32);
*
* bool equals = parcFileChunker_Equals(chunkerA, chunkerB);
* }
* @endcode
*/
bool parcFileChunker_Equals(const PARCFileChunker *chunkerA, const PARCFileChunker *chunkerB);
/**
* Return an iterator to traverse the chunks of the underlying data in sequential order.
*
* This function can only be called once per chunker instance since the iterator
* will mutate internal state of the chunker.
*
* @param [in] chunker A `PARCFileChunker` instance.
*
* @return a `PARCIterator` that traverses the chunks of the underlying data.
*
* Example
* @code
* {
* char *fileToChunk = ...
* PARCFileChunker *chunker = parcFileChunker_Create(fileToChunk, 32);
*
* PARCIterator *itr = parcFileChunker_ForwardIterator(chunker);
*
* // use the iterator to traverse the chunker
* }
* @endcode
*/
PARCIterator *parcFileChunker_ForwardIterator(const PARCFileChunker *chunker);
/**
* Return an iterator to traverse the chunks of the underlying data in sequential order.
*
* This function can only be called once per chunker instance since the iterator
* will mutate internal state of the chunker.
*
* @param [in] chunker A `PARCFileChunker` instance.
*
* @return a `PARCIterator` that traverses the chunks of the underlying data.
*
* Example
* @code
* {
* char *fileToChunk = ...
* PARCFileChunker *chunker = parcFileChunker_Create(fileToChunk, 32);
*
* PARCIterator *itr = parcFileChunker_ReverseIterator(chunker);
*
* // use the iterator to traverse the chunker
* }
* @endcode
*/
PARCIterator *parcFileChunker_ReverseIterator(const PARCFileChunker *chunker);
/**
* Get the chunk size of a `PARCFileChunker.`
*
* @param [in] chunker A `PARCFileChunker` instance.
*
* @return the chunk size
*
* Example
* @code
* {
* PARCBuffer *dataToChunk = ...
* PARCFileChunker *chunker = ...
*
* size_t chunkSize = parcFileChunker_GetChunkSize(chunker);
* }
* @endcode
*/
size_t parcFileChunker_GetChunkSize(const PARCFileChunker *chunker);
#endif // libparc_parc_FileChunker_h
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