1
0
Fork 0
mirror of https://git.rwth-aachen.de/acs/public/villas/node/ synced 2025-03-30 00:00:11 +01:00
VILLASnode/include/villas/io_format.h

143 lines
4.5 KiB
C

/** Read / write sample data in different formats.
*
* @file
* @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
* @copyright 2017, Institute for Automation of Complex Power Systems, EONERC
* @license GNU General Public License (version 3)
*
* VILLASnode
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*********************************************************************************/
#pragma once
#include <stdio.h>
/* Forward declarations */
struct sample;
struct io;
enum io_format_flags {
IO_FORMAT_BINARY = (1 << 8)
};
struct io_format {
int (*init)(struct io *io);
int (*destroy)(struct io *io);
/** @{
* High-level interface
*/
/** Open an IO stream.
*
* @see fopen()
*/
int (*open)(struct io *io, const char *uri);
/** Close an IO stream.
*
* @see fclose()
*/
int (*close)(struct io *io);
/** Check if end-of-file was reached.
*
* @see feof()
*/
int (*eof)(struct io *io);
/** Rewind an IO stream.
*
* @see rewind()
*/
void (*rewind)(struct io *io);
/** Get a file descriptor which can be used with select / poll */
int (*fd)(struct io *io);
/** Flush buffered data to disk.
*
* @see fflush()
*/
int (*flush)(struct io *io);
int (*print)(struct io *io, struct sample *smps[], unsigned cnt);
int (*scan)( struct io *io, struct sample *smps[], unsigned cnt);
/** @} */
/** @{
* Low-level interface
*/
/** @see io_format_sscan */
int (*sscan)(char *buf, size_t len, size_t *rbytes, struct sample *smps[], unsigned cnt, int flags);
/** @see io_format_sprint */
int (*sprint)(char *buf, size_t len, size_t *wbytes, struct sample *smps[], unsigned cnt, int flags);
/** @see io_format_fscan */
int (*fscan)(FILE *f, struct sample *smps[], unsigned cnt, int flags);
/** @see io_format_fprint */
int (*fprint)(FILE *f, struct sample *smps[], unsigned cnt, int flags);
/** @} */
size_t size; /**< Number of bytes to allocate for io::_vd */
int flags; /**< A set of flags which is automatically used. */
};
struct io_format * io_format_lookup(const char *name);
/** Parse samples from the buffer \p buf with a length of \p len bytes.
*
* @param buf[in] The buffer of data which should be parsed / de-serialized.
* @param len[in] The length of the buffer \p buf.
* @param rbytes[out] The number of bytes which have been read from \p buf.
* @param smps[out] The array of pointers to samples.
* @param cnt[in] The number of pointers in the array \p smps.
*
* @retval >=0 The number of samples which have been parsed from \p buf and written into \p smps.
* @retval <0 Something went wrong.
*/
int io_format_sscan(struct io_format *fmt, char *buf, size_t len, size_t *rbytes, struct sample *smps[], unsigned cnt, int flags);
/** Print \p cnt samples from \p smps into buffer \p buf of length \p len.
*
* @param buf[out] The buffer which should be filled with serialized data.
* @param len[in] The length of the buffer \p buf.
* @param rbytes[out] The number of bytes which have been written to \p buf. Ignored if NULL.
* @param smps[in] The array of pointers to samples.
* @param cnt[in] The number of pointers in the array \p smps.
*
* @retval >=0 The number of samples from \p smps which have been written into \p buf.
* @retval <0 Something went wrong.
*/
int io_format_sprint(struct io_format *fmt, char *buf, size_t len, size_t *wbytes, struct sample *smps[], unsigned cnt, int flags);
/** Parse up to \p cnt samples from stream \p f into array \p smps.
*
* @retval >=0 The number of samples which have been parsed from \p f and written into \p smps.
* @retval <0 Something went wrong.
*/
int io_format_fscan(struct io_format *fmt, FILE *f, struct sample *smps[], unsigned cnt, int flags);
/** Print \p cnt samples from \p smps to stream \p f.
*
* @retval >=0 The number of samples from \p smps which have been written to \p f.
* @retval <0 Something went wrong.
*/
int io_format_fprint(struct io_format *fmt, FILE *f, struct sample *smps[], unsigned cnt, int flags);