mirror of
https://git.proxmox.com/git/mirror_frr
synced 2025-11-04 11:45:06 +00:00
78 lines
2.6 KiB
C
78 lines
2.6 KiB
C
/*
|
|
* Simple string buffer
|
|
*
|
|
* Copyright (C) 2017 Christian Franke
|
|
*
|
|
* This file is part of FRR.
|
|
*
|
|
* FRR 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.
|
|
*
|
|
* FRR 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 FRR; see the file COPYING. If not, write to the Free
|
|
* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
|
|
* 02111-1307, USA.
|
|
*/
|
|
#ifndef SBUF_H
|
|
#define SBUF_H
|
|
|
|
/*
|
|
* sbuf provides a simple string buffer. One application where this comes
|
|
* in handy is the parsing of binary data: If there is an error in the parsing
|
|
* process due to invalid input data, printing an error message explaining what
|
|
* went wrong is definitely useful. However, just printing the actual error,
|
|
* without any information about the previous parsing steps, is usually not very
|
|
* helpful.
|
|
* Using sbuf, the parser can log the whole parsing process into a buffer using
|
|
* a printf like API. When an error ocurrs, all the information about previous
|
|
* parsing steps is there in the log, without any need for backtracking, and can
|
|
* be used to give a detailed and useful error description.
|
|
* When parsing completes successfully without any error, the log can just be
|
|
* discarded unless debugging is turned on, to not spam the log.
|
|
*
|
|
* For the described usecase, the code would look something like this:
|
|
*
|
|
* int sbuf_example(..., char **parser_log)
|
|
* {
|
|
* struct sbuf logbuf;
|
|
*
|
|
* sbuf_init(&logbuf, NULL, 0);
|
|
* sbuf_push(&logbuf, 0, "Starting parser\n");
|
|
*
|
|
* int rv = do_parse(&logbuf, ...);
|
|
*
|
|
* *parser_log = sbuf_buf(&logbuf);
|
|
*
|
|
* return 1;
|
|
* }
|
|
*
|
|
* In this case, sbuf_example uses a string buffer with undefined size, which will
|
|
* be allocated on the heap by sbuf. The caller of sbuf_example is expected to free
|
|
* the string returned in parser_log.
|
|
*/
|
|
|
|
struct sbuf {
|
|
bool fixed;
|
|
char *buf;
|
|
size_t size;
|
|
size_t pos;
|
|
int indent;
|
|
};
|
|
|
|
void sbuf_init(struct sbuf *dest, char *buf, size_t size);
|
|
void sbuf_reset(struct sbuf *buf);
|
|
const char *sbuf_buf(struct sbuf *buf);
|
|
void sbuf_free(struct sbuf *buf);
|
|
#include "lib/log.h"
|
|
void sbuf_push(struct sbuf *buf, int indent, const char *format, ...)
|
|
PRINTF_ATTRIBUTE(3, 4);
|
|
|
|
#endif
|