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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_FileOutputStream.h
* @ingroup inputoutput
* @brief A file output stream is an output stream for writing data to a File or to a FileDescriptor.
*
* Whether or not a file is available or may be created depends upon the underlying platform.
* Some platforms, in particular, allow a file to be opened for writing by only one FileOutputStream
* (or other file-writing object) at a time. In such situations the constructors in this class will
* fail if the file involved is already open.
*
*/
#ifndef libparc_parc_FileOutputStream_h
#define libparc_parc_FileOutputStream_h
#include <parc/algol/parc_Buffer.h>
#include <parc/algol/parc_OutputStream.h>
struct parc_file_output_stream;
typedef struct parc_file_output_stream PARCFileOutputStream;
/**
* The mapping of a `PARCFileOutputStream` to the generic `PARCInputStream`.
*
*/
extern PARCOutputStreamInterface *PARCFileOutputStreamAsPARCOutputStream;
/**
* Create a new output stream on a file descriptor.
*
* Caution: When the resulting `PARCFileOutputStream` is released, the file descriptor is closed.
* If you wrap STDOUT_FILENO, for example, the standard output of the application will be closed
* when this PARCFileOutputStream is released.
* To avoid this, use dup(2) or dup2(2).
*
* @param [in] fileDescriptor The fileDescriptor for the file on which to create an output stream.
*
* @return A pointer to a new instance of `PARCFileOutputStream`
*
* Example:
* @code
* {
* <#example#>
* }
* @endcode
*/
PARCFileOutputStream *parcFileOutputStream_Create(int fileDescriptor);
/**
* Convert an instance of `PARCFileOutputStream` to a `PARCOutputStream`.
*
* @param [in] fileOutputStream A pointer to a valid PARCFileOutputStream.
*
* @return A pointer to a new instance of `PARCOutputStream`.
*
* Example:
* @code
* <#example#>
* @endcode
*/
PARCOutputStream *parcFileOutputStream_AsOutputStream(PARCFileOutputStream *fileOutputStream);
/**
* Acquire a new reference to an instance of `PARCFileOutputStream`.
*
* The reference count to the instance is incremented.
*
* @param [in] stream The instance of `PARCFileOutputStream` to which to refer.
*
* @return The same value as the input parameter @p stream
*
* Example:
* @code
* {
* <#example#>
* }
* @endcode
*/
PARCFileOutputStream *parcFileOutputStream_Acquire(const PARCFileOutputStream *stream);
/**
* Release a `PARCFileOutputStream` reference.
*
* Only the last invocation where the reference count is decremented to zero,
* will actually destroy the `PARCFileOutputStream`.
*
* @param [in,out] streamPtr is a pointer to the `PARCFileOutputStream` reference.
*
* Example:
* @code
* <#example#>
* @endcode
*/
void parcFileOutputStream_Release(PARCFileOutputStream **streamPtr);
/**
* Write the contents of a {@link PARCBuffer} to the given `PARCFileOutputStream`.
*
* The contents of the `PARCBuffer` from the current position to the limit are written to the `PARCFileOutputStream`.
* When this function returns the position is set to the end of the last successfully written byte of data.
*
* @param [in,out] outputStream The `PARCOutputStream` to write to.
* @param [in] buffer The `PARCBuffer` to write, from the current position of the buffer to its limit.
*
* @return true The entire contents of the `PARCBuffer` were written.
* @return false The entire contents of the `PARCBuffer` were not written.
*
* Example:
* @code
* {
* PARCFileOutputStream *stream =
* parcFileOutputStream_Create(open("/tmp/test_parc_FileOutputStream", O_CREAT|O_WRONLY|O_TRUNC, 0600));
*
* PARCBuffer *buffer = parcBuffer_Allocate(16 * 1024*1024);
*
* parcFileOutputStream_Write(stream, buffer);
*
* assertFalse(parcBuffer_HasRemaining(buffer), "Expected the buffer to be emtpy");
*
* parcBuffer_Release(&buffer);
*
* parcFileOutputStream_Release(&stream);
* }
* @endcode
*/
bool parcFileOutputStream_Write(PARCFileOutputStream *outputStream, PARCBuffer *buffer);
#endif // libparc_parc_FileOutputStream_h
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