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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_Chunker.h
+ * @ingroup ContentObject
+ * @brief A Chunker is an object that breaks up a large piece of data from a `PARCBuffer`
+ * or a file and provides an iterator to walk over the chunks in sequential order.
+ *
+ */
+
+#ifndef libparc_parc_Chunker_h
+#define libparc_parc_Chunker_h
+
+#include <parc/algol/parc_Object.h>
+#include <parc/algol/parc_Iterator.h>
+
+struct parc_chunker;
+/**
+ * @typedef PARCChunker
+ * @brief The PARC Chunker
+ */
+typedef struct parc_chunker PARCChunker;
+
+typedef struct PARCChunkerInterface {
+ /**
+ * @see parcChunker_ForwardIterator
+ */
+ void *(*ForwardIterator)(const void *original);
+
+ /**
+ * @see parcChunker_ReverseIterator
+ */
+ void *(*ReverseIterator)(const void *original);
+
+ /**
+ * @see parcChunker_GetChunkSize
+ */
+ size_t (*GetChunkSize)(const void *original);
+} PARCChunkerInterface;
+
+/**
+ * Create a new chunker from the given concrete instance.
+ *
+ * @param [in] instance A `PARCChunker` instance.
+ * @param [in] interface The interface implementation of the chunker.
+ *
+ * @retval PARCChunker A newly allocated `PARCChunker`
+ * @retval NULL An error occurred.
+ *
+ * Example
+ * @code
+ * {
+ * PARCBuffer *dataToChunk = ...
+ * PARCChunkerBuffer *bufferChunker = parcBufferChunker_Create(dataToChunk, 32);
+ * PARCChunker *chunker = parcChunker_Create(bufferCunker, &PARCBufferChunkerAsChunker);
+ * }
+ */
+PARCChunker *parcChunker_Create(PARCObject *instance, PARCChunkerInterface *interface);
+
+/**
+ * Create a new chunker to segment data contained in a file.
+ *
+ * @param [in] fileName The name of a file from which to read.
+ * @param [in] chunkSize The size per chunk.
+ *
+ * @retval PARCChunker A newly allocated `PARCChunker`
+ * @retval NULL An error occurred.
+ *
+ * Example
+ * @code
+ * {
+ * char *bigFileName = "big_file.bin";
+ * PARCChunker *chunker = parcChunker_CreateFromBuffer(bigFileName, 32);
+ * }
+ */
+//PARCChunker *parcChunker_CreateFromFile(char *fileName, size_t maxDataSize);
+
+/**
+ * Increase the number of references to a `PARCChunker` instance.
+ *
+ * Note that new `PARCChunker` is not created,
+ * only that the given `PARCChunker` reference count is incremented.
+ * Discard the reference by invoking {@link parcChunker_Release}.
+ *
+ * @param [in] chunker A pointer to the original `PARCChunker`.
+ * @return The value of the input parameter @p chunker.
+ *
+ * Example:
+ * @code
+ * {
+ * PARCChunker *original = ...
+ *
+ * PARCChunker *reference = parcChunker_Acquire(original);
+ *
+ * parcChunker_Release(&original);
+ * parcChunker_Release(&reference);
+ * }
+ * @endcode
+ *
+ * @see parcChunker_Release
+ */
+PARCChunker *parcChunker_Acquire(const PARCChunker *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
+ * {
+ * ...
+ *
+ * PARCChunker *chunker = parcChunker_Acquire(instance);
+ *
+ * parcChunker_Release(&chunker);
+ * }
+ * @endcode
+ */
+void parcChunker_Release(PARCChunker **chunkerP);
+
+/**
+ * Determine if two `PARCChunker` instances are equal.
+ *
+ * The following equivalence relations on non-null `PARCChunker` instances are maintained:
+ *
+ * * It is reflexive: for any non-null reference value x, `parcChunker_Equals(x, x)`
+ * must return true.
+ *
+ * * It is symmetric: for any non-null reference values x and y,
+ * `parcChunker_Equals(x, y)` must return true if and only if
+ * `parcChunker_Equals(y, x)` returns true.
+ *
+ * * It is transitive: for any non-null reference values x, y, and z, if
+ * `parcChunker_Equals(x, y)` returns true and
+ * `parcChunker_Equals(y, z)` returns true,
+ * then `parcChunker_Equals(x, z)` must return true.
+ *
+ * * It is consistent: for any non-null reference values x and y, multiple
+ * invocations of `parcChunker_Equals(x, y)` consistently return true or
+ * consistently return false.
+ *
+ * * For any non-null reference value x, `parcChunker_Equals(x, NULL)` must
+ * return false.
+ *
+ * @param chunkerA A pointer to a `PARCChunker` instance.
+ * @param chunkerB A pointer to a `PARCChunker` instance.
+ * @return true if the two `PARCChunker` instances are equal.
+ *
+ * Example:
+ * @code
+ * {
+ * PARCBuffer *dataToChunk = ...
+ * PARCChunker *chunkerA = ...
+ * PARCChunker *chunkerB = ...
+ *
+ * bool equals = parcChunker_Equals(chunkerA, chunkerB);
+ * }
+ * @endcode
+ */
+bool parcChunker_Equals(const PARCChunker *chunkerA, const PARCChunker *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 `PARCChunker` instance.
+ *
+ * @return a `PARCIterator` that traverses the chunks of the underlying data.
+ *
+ * Example
+ * @code
+ * {
+ * PARCBuffer *dataToChunk = ...
+ * PARCBufferChunker *chunker = ...
+ *
+ * PARCIterator *itr = parcChunker_ForwardIterator(chunker);
+ *
+ * // use the iterator to traverse the chunker
+ * }
+ * @endcode
+ */
+PARCIterator *parcChunker_ForwardIterator(const PARCChunker *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 `PARCChunker` instance.
+ *
+ * @return a `PARCIterator` that traverses the chunks of the underlying data.
+ *
+ * Example
+ * @code
+ * {
+ * PARCBuffer *dataToChunk = ...
+ * PARCChunker *chunker = ...
+ *
+ * PARCIterator *itr = parcChunker_ReverseIterator(chunker);
+ *
+ * // use the iterator to traverse the chunker
+ * }
+ * @endcode
+ */
+PARCIterator *parcChunker_ReverseIterator(const PARCChunker *chunker);
+
+/**
+ * Get the chunk size of a `PARCChunker.`
+ *
+ * @param [in] chunker A `PARCChunker` instance.
+ *
+ * @return the chunk size
+ *
+ * Example
+ * @code
+ * {
+ * PARCBuffer *dataToChunk = ...
+ * PARCChunker *chunker = ...
+ *
+ * size_t chunkSize = parcChunker_GetChunkSize(chunker);
+ * }
+ * @endcode
+ */
+size_t parcChunker_GetChunkSize(const PARCChunker *chunker);
+#endif // libparc_parc_Chunker_h