1/* Copyright (C) 2012 Monty Program Ab
2
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation; version 2 of the License.
6
7 This program is distributed in the hope that it will be useful,
8 but WITHOUT ANY WARRANTY; without even the implied warranty of
9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 GNU General Public License for more details.
11
12 You should have received a copy of the GNU General Public License
13 along with this program; if not, write to the Free Software
14 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA */
15
16#ifndef MYSQL_SERVICE_LOGGER_INCLUDED
17#define MYSQL_SERVICE_LOGGER_INCLUDED
18
19#ifndef MYSQL_ABI_CHECK
20#include <stdarg.h>
21#endif
22
23/**
24 @file
25 logger service
26
27 Log file with rotation implementation.
28
29 This service implements logging with possible rotation
30 of the log files. Interface intentionally tries to be similar to FILE*
31 related functions.
32
33 So that one can open the log with logger_open(), specifying
34 the limit on the logfile size and the rotations number.
35
36 Then it's possible to write messages to the log with
37 logger_printf or logger_vprintf functions.
38
39 As the size of the logfile grows over the specified limit,
40 it is renamed to 'logfile.1'. The former 'logfile.1' becomes
41 'logfile.2', etc. The file 'logfile.rotations' is removed.
42 That's how the rotation works.
43
44 The rotation can be forced with the logger_rotate() call.
45
46 Finally the log should be closed with logger_close().
47
48@notes:
49 Implementation checks the size of the log file before it starts new
50 printf into it. So the size of the file gets over the limit when it rotates.
51
52 The access is secured with the mutex, so the log is threadsafe.
53*/
54
55
56#ifdef __cplusplus
57extern "C" {
58#endif
59
60typedef struct logger_handle_st LOGGER_HANDLE;
61
62extern struct logger_service_st {
63 void (*logger_init_mutexes)();
64 LOGGER_HANDLE* (*open)(const char *path,
65 unsigned long long size_limit,
66 unsigned int rotations);
67 int (*close)(LOGGER_HANDLE *log);
68 int (*vprintf)(LOGGER_HANDLE *log, const char *fmt, va_list argptr);
69 int (*printf)(LOGGER_HANDLE *log, const char *fmt, ...);
70 int (*write)(LOGGER_HANDLE *log, const char *buffer, size_t size);
71 int (*rotate)(LOGGER_HANDLE *log);
72} *logger_service;
73
74#ifdef MYSQL_DYNAMIC_PLUGIN
75
76#define logger_init_mutexes logger_service->logger_init_mutexes
77#define logger_open(path, size_limit, rotations) \
78 (logger_service->open(path, size_limit, rotations))
79#define logger_close(log) (logger_service->close(log))
80#define logger_rotate(log) (logger_service->rotate(log))
81#define logger_vprintf(log, fmt, argptr) (logger_service->\
82 vprintf(log, fmt, argptr))
83#define logger_printf (*logger_service->printf)
84#define logger_write(log, buffer, size) \
85 (logger_service->write(log, buffer, size))
86#else
87
88 void logger_init_mutexes();
89 LOGGER_HANDLE *logger_open(const char *path,
90 unsigned long long size_limit,
91 unsigned int rotations);
92 int logger_close(LOGGER_HANDLE *log);
93 int logger_vprintf(LOGGER_HANDLE *log, const char *fmt, va_list argptr);
94 int logger_printf(LOGGER_HANDLE *log, const char *fmt, ...);
95 int logger_write(LOGGER_HANDLE *log, const char *buffer, size_t size);
96 int logger_rotate(LOGGER_HANDLE *log);
97#endif
98
99
100#ifdef __cplusplus
101}
102#endif
103
104#endif /*MYSQL_SERVICE_LOGGER_INCLUDED*/
105
106