#ifndef __FILEUTIL_H__
# define __FILEUTIL_H__

#ifdef __cplusplus
extern "C" {
#endif

#include <stdio.h>
#include <stdbool.h>
#include <fcntl.h>

/* Check whether a buffer has written data to flush. */
#define __fp_hasbuf_write(fp) \
   (fp->buf && fp->bufdir == __FILE_BUF_WRITE && fp->bufpos > 0)
/* Check whether a buffer has read data to yield. */
#define __fp_hasbuf_read(fp) \
   (fp->buf && fp->bufdir == __FILE_BUF_READ && fp->bufpos < fp->bufread)

/* Open a file descriptor in a pre-allocated FILE. */
int __fp_open(FILE *fp, int fd, bool use_buffering);

/* Close fp and free all of its resources. */
void __fp_close(FILE *fp, bool free_fp);

/* Remove the buffer on fp. */
void __fp_remove_buffer(FILE *fp);

/* Set the specified buffer on fp (can be NULL), in which case malloc().
   Returns true on success, false on error. */
bool __fp_set_buffer(FILE *fp, void *buf, size_t size);

/* Set reading mode on the buffer. */
void __fp_buffer_mode_read(FILE *fp);

/* Set writing mode on the buffer. */
void __fp_buffer_mode_write(FILE *fp);

/* fread() with an extra option to stop at a certain character (usually '\n');
   set -1 to disable. */
ssize_t __fp_fread2(FILE *fp, void *data, size_t request_size, int stop_char);

/* Reads data from the buffer. Always reads as much as possible, up to size.
   Returns amount of data read; if >= 0 but < size, the buffer should be
   refilled. Returns -1 to indicate that unbuffered access should be used.
   Allows reading from temporary ungetc() buffers and cleans them. */
ssize_t __fp_buffered_read(FILE *fp, void *data, size_t size, int stop_char);

/* Reads data from a file descriptor; updates the fdpos and sets the error
   indicator. Returns 0 on success, EOF on error. */
ssize_t __fp_read(FILE *fp, void *data, size_t size);

/* Write data to a file descriptor; updates the fdpos and sets the error
   indicator. Returns 0 on success, EOF on error. */
ssize_t __fp_write(FILE *fp, void const *data, size_t size);

/* Parse mode bits. Returns corresponding open() flags if successful, -1 if the
   mode is invalid. If [fp != NULL], also sets the fields of [fp]. Sets
   errno = EINVAL in case of error. */
int __fp_parse_mode(char const *mode, FILE *fp);

#ifdef __cplusplus
}
#endif

#endif /*__FILEUTIL_H__*/