utility/FullIo.hpp

/*
 * Copyright (c) 2015, Intel Corporation
 * All rights reserved.
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 * are permitted provided that the following conditions are met:
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 * list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation and/or
 * other materials provided with the distribution.
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 * 3. Neither the name of the copyright holder nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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#pragma once

#include <cstddef>

namespace utility
{

/** Write *completely* a buffer in a file descriptor.
 *
 * A wrapper around unistd::write that resumes write on incomplete access
 * and EAGAIN/EINTR error.
 *
 * @see man 2 write for the parameters.
 *
 * @return true if the buffer could be completely written,
 *        false on failure (see write's man errno section).
 */
bool fullWrite(int fd, const void *buf, size_t count);

/** Fill a buffer from a file descriptor.
 *
 * A wrapper around unistd::read that resumes read on incomplete access
 * and EAGAIN/EINTR error.
 *
 * @see man 2 read for the parameters.
 *
 * @return true if the buffer could be completely fill,
 *        false on failure (see read's man errno section).
 *
 * If the buffer could not be filled due to an EOF, return false but set
 * errno to 0.
 * @TODO Add a custom strerror to prevent logging "success" (`sterror(0)`) on
 *       EOF errors ?
 */
bool fullRead(int fd, void *buf, size_t count);

} // namespace utility