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/*
* Buffering to output and input.
* Copyright (C) 1998 Kunihiro Ishiguro
*
* This file is part of GNU Zebra.
*
* GNU Zebra 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 2, or (at your
* option) any later version.
*
* GNU Zebra 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; see the file COPYING; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _ZEBRA_BUFFER_H
#define _ZEBRA_BUFFER_H
/* Create a new buffer. Memory will be allocated in chunks of the given
size. If the argument is 0, the library will supply a reasonable
default size suitable for buffering socket I/O. */
extern struct buffer *buffer_new(size_t);
/* Free all data in the buffer. */
extern void buffer_reset(struct buffer *);
/* This function first calls buffer_reset to release all buffered data.
Then it frees the struct buffer itself. */
extern void buffer_free(struct buffer *);
/* Add the given data to the end of the buffer. */
extern void buffer_put(struct buffer *, const void *, size_t);
/* Add a single character to the end of the buffer. */
extern void buffer_putc(struct buffer *, uint8_t);
/* Add a NUL-terminated string to the end of the buffer. */
extern void buffer_putstr(struct buffer *, const char *);
/* Add given data, inline-expanding \n to \r\n */
extern void buffer_put_crlf(struct buffer *b, const void *p, size_t size);
/* Combine all accumulated (and unflushed) data inside the buffer into a
single NUL-terminated string allocated using XMALLOC(MTYPE_TMP). Note
that this function does not alter the state of the buffer, so the data
is still inside waiting to be flushed. */
char *buffer_getstr(struct buffer *);
/* Returns 1 if there is no pending data in the buffer. Otherwise returns 0. */
int buffer_empty(struct buffer *);
typedef enum {
/* An I/O error occurred. The buffer should be destroyed and the
file descriptor should be closed. */
BUFFER_ERROR = -1,
/* The data was written successfully, and the buffer is now empty
(there is no pending data waiting to be flushed). */
BUFFER_EMPTY = 0,
/* There is pending data in the buffer waiting to be flushed. Please
try flushing the buffer when select indicates that the file
descriptor
is writeable. */
BUFFER_PENDING = 1
} buffer_status_t;
/* Try to write this data to the file descriptor. Any data that cannot
be written immediately is added to the buffer queue. */
extern buffer_status_t buffer_write(struct buffer *, int fd, const void *,
size_t);
/* This function attempts to flush some (but perhaps not all) of
the queued data to the given file descriptor. */
extern buffer_status_t buffer_flush_available(struct buffer *, int fd);
/* The following 2 functions (buffer_flush_all and buffer_flush_window)
are for use in lib/vty.c only. They should not be used elsewhere. */
/* Call buffer_flush_available repeatedly until either all data has been
flushed, or an I/O error has been encountered, or the operation would
block. */
extern buffer_status_t buffer_flush_all(struct buffer *, int fd);
/* Attempt to write enough data to the given fd to fill a window of the
given width and height (and remove the data written from the buffer).
If !no_more, then a message saying " --More-- " is appended.
If erase is true, then first overwrite the previous " --More-- " message
with spaces.
Any write error (including EAGAIN or EINTR) will cause this function
to return -1 (because the logic for handling the erase and more features
is too complicated to retry the write later).
*/
extern buffer_status_t buffer_flush_window(struct buffer *, int fd, int width,
int height, int erase, int no_more);
#endif /* _ZEBRA_BUFFER_H */
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