mirror_frr/lib/buffer.h
ajs 49ff6d9d7a 2004-11-04 Andrew J. Schorr <ajschorr@alumni.princeton.edu>
* vty.c: Vtysh connections to daemons should use buffering.
	  (vty_out) Remove exception for vty_shell_serv, just use buffer_write.
	  (vty_new) Increase output buffer size to 4096 rounded up to a
	  multiple of pagesize.
	  (vtysh_read) After command has been executed and all output buffered,
	  call buffer_flush_available and schedule further writes if the
	  buffers are not yet empty.
	  (vtysh_write) New function to flush output to vtysh when the socket
	  is writeable.
	  (vty_event) Added new VTYSH_WRITE event for flushing buffers to vtysh
	  clients.  Also, should save read thread in vty->t_read so the
	  thread can be cancelled in vty_close.
	* buffer.h: In struct buffer_data, remove unused "parent" field.
	  Convert "unsigned char *data" to "unsigned char data[0]" to save
	  a malloc.  Declare new function buffer_flush_available that works
	  with non-blocking sockets.
	* buffer.c: (buffer_data_new) Use a single malloc now that data is
	  a variable-size array at end of structure.
	  (buffer_data_free) Just a single free now that data is part of the
	  structure.
	  (buffer_write) Simplify the logic to make behavior more transparent.
	  (buffer_flush) Decrease b->length as data is written out.
	  (buffer_flush_vty_all) Decrease b->length as buffers are freed.
	  (buffer_flush_vty) Decrease b->length as data is written out.
	  (buffer_flush_available) New function to flush non-blocking sockets.
2004-11-04 19:26:16 +00:00

84 lines
2.5 KiB
C

/*
* 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 GNU Zebra; see the file COPYING. If not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef _ZEBRA_BUFFER_H
#define _ZEBRA_BUFFER_H
/* Buffer master. */
struct buffer
{
/* Data list. */
struct buffer_data *head;
struct buffer_data *tail;
/* Current allocated data. */
unsigned long alloc;
/* Size of each buffer_data chunk. */
unsigned long size;
/* For allocation. */
struct buffer_data *unused_head;
struct buffer_data *unused_tail;
/* Current total length of this buffer. */
unsigned long length;
};
/* Data container. */
struct buffer_data
{
struct buffer_data *next;
struct buffer_data *prev;
/* Current pointer. */
unsigned long cp;
/* Start pointer. */
unsigned long sp;
/* Actual data stream (variable length). */
unsigned char data[0]; /* real dimension is buffer->size */
};
/* Buffer prototypes. */
struct buffer *buffer_new (size_t);
int buffer_write (struct buffer *, const void *, size_t);
void buffer_free (struct buffer *);
char *buffer_getstr (struct buffer *);
int buffer_putc (struct buffer *, u_char);
int buffer_putstr (struct buffer *, const char *);
void buffer_reset (struct buffer *);
int buffer_flush_all (struct buffer *, int);
int buffer_flush_vty_all (struct buffer *, int, int, int);
int buffer_flush_window (struct buffer *, int, int, int, int, int);
int buffer_empty (struct buffer *);
/* buffer_flush_available attempts to flush the queued data to the given
file descriptor. It returns 0 if the buffers are now empty (after
flushing), or 1 if more data remains on the buffer queue (must be flushed
later). This function (unlike the other buffer_flush* functions) is
designed to work with non-blocking file descriptors. */
int buffer_flush_available(struct buffer *, int fd);
#endif /* _ZEBRA_BUFFER_H */