From ec688b4723a041044226358bcd4dd6e2da39da49 Mon Sep 17 00:00:00 2001 From: Luca Muscariello Date: Thu, 23 Feb 2017 17:01:02 +0100 Subject: Initial commit: cframework. Longbow and Libparc Change-Id: I90378dbd30da6033b20fb1f829b3b822cf366c59 Signed-off-by: Luca Muscariello --- libparc/parc/algol/parc_Chunker.h | 250 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 250 insertions(+) create mode 100755 libparc/parc/algol/parc_Chunker.h (limited to 'libparc/parc/algol/parc_Chunker.h') diff --git a/libparc/parc/algol/parc_Chunker.h b/libparc/parc/algol/parc_Chunker.h new file mode 100755 index 00000000..305acad7 --- /dev/null +++ b/libparc/parc/algol/parc_Chunker.h @@ -0,0 +1,250 @@ +/* + * 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 +#include + +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 -- cgit 1.2.3-korg