1/* Copyright (c) 1993-2002
2 *      Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de)
3 *      Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de)
4 * Copyright (c) 1987 Oliver Laumann
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2, or (at your option)
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program (see the file COPYING); if not, write to the
18 * Free Software Foundation, Inc.,
19 * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
20 *
21 ****************************************************************
22 * $Id: logfile.h,v 1.11 1994/05/31 12:33:27 jnweiger Exp $ FAU
23 */
24
25struct logfile
26{
27  struct logfile *next;
28  FILE *fp;		/* a hopefully uniq filepointer to the log file */
29  char *name;		/* the name. used to reopen, when stat fails. */
30  int opencount;	/* synchronize logfopen() and logfclose() */
31  int writecount;	/* increments at logfwrite(), counts write() and fflush() */
32  int flushcount;	/* increments at logfflush(), zeroed at logfwrite() */
33  struct stat *st;	/* how the file looks like */
34};
35
36/*
37 * open a logfile, The second argument must be NULL, when the named file
38 * is already a logfile or must be a appropriatly opened file pointer
39 * otherwise.
40 * example: l = logfopen(name, islogfile(name) : NULL ? fopen(name, "a"));
41 */
42struct logfile *logfopen __P((char *name, FILE *fp));
43
44/*
45 * lookup a logfile by name. This is useful, so that we can provide
46 * logfopen with a nonzero second argument, exactly when needed.
47 * islogfile(NULL); returns nonzero if there are any open logfiles at all.
48 */
49int islogfile __P((char *name));
50
51/*
52 * logfclose does free()
53 */
54int logfclose __P((struct logfile *));
55int logfwrite __P((struct logfile *, char *, int));
56
57/*
58 * logfflush should be called periodically. If no argument is passed,
59 * all logfiles are flushed, else the specified file
60 * the number of flushed filepointers is returned
61 */
62int logfflush __P((struct logfile *ifany));
63
64/*
65 * a reopen function may be registered here, in case you want to bring your
66 * own (more secure open), it may come along with a private data pointer.
67 * this function is called, whenever logfwrite/logfflush detect that the
68 * file has been (re)moved, truncated or changed by someone else.
69 * if you provide NULL as parameter to logreopen_register, the builtin
70 * reopen function will be reactivated.
71 */
72void logreopen_register __P((int (*fn) __P((char *, int, struct logfile *)) ));
73
74/*
75 * Your custom reopen function is required to reuse the exact
76 * filedescriptor.
77 * See logfile.c for further specs and an example.
78 *
79 * lf_move_fd may help you here, if you do not have dup2(2).
80 * It closes fd and opens wantfd to access whatever fd accessed.
81 */
82int lf_move_fd __P((int fd, int wantfd));
83