/*
 * Copyright (c) 2020 YuQing <384681@qq.com>
 *
 * This program is free software: you can use, redistribute, and/or modify
 * it under the terms of the Lesser GNU General Public License, version 3
 * or later ("LGPL"), as published by the Free Software Foundation.
 *
 * 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.
 *
 * You should have received a copy of the Lesser GNU General Public License
 * along with this program. If not, see <https://www.gnu.org/licenses/>.
 */

#ifndef BUFFERED_FILE_WRITER_H
#define BUFFERED_FILE_WRITER_H

#include "common_define.h"

typedef struct
{
    int fd;
    int buffer_size;
    char filename[MAX_PATH_SIZE];
    char *buff;
    char *current;
    char *buff_end;
    char *water_mark;
} BufferedFileWriter;

#ifdef __cplusplus
extern "C" {
#endif

/** open buffered file writer
 *  parameters:
 *         writer: the writer
 *         filename: the filename to write
 *         buffer_size: the buffer size, <= 0 for recommend 64KB
 *         max_written_once: max written bytes per call, <= 0 for 256
 *         mode: the file privilege such as 0644
 *  return: error code, 0 for success, != 0 for errno
 */
int buffered_file_writer_open_ex(BufferedFileWriter *writer,
        const char *filename, const int buffer_size,
        const int max_written_once, const int mode);

static inline int buffered_file_writer_open(BufferedFileWriter *writer,
        const char *filename)
{
    const int buffer_size = 0;
    const int max_written_once = 0;
    const int mode = 0644;
    return buffered_file_writer_open_ex(writer, filename,
            buffer_size, max_written_once, mode);
}

/** close buffered file writer
 * parameters:
 *         writer: the writer
 *  return: error code, 0 for success, != 0 for errno
 */
int buffered_file_writer_close(BufferedFileWriter *writer);

int buffered_file_writer_append(BufferedFileWriter *writer,
        const char *format, ...);

int buffered_file_writer_append_buff(BufferedFileWriter *writer,
        const char *buff, const int len);

int buffered_file_writer_flush(BufferedFileWriter *writer);

#ifdef __cplusplus
}
#endif

#endif