1/*! \file exif-log.h
2 *  \brief Log message infrastructure
3 */
4/*
5 * Copyright (c) 2004 Lutz Mueller <lutz@users.sourceforge.net>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA  02110-1301  USA.
21 */
22
23#ifndef __EXIF_LOG_H__
24#define __EXIF_LOG_H__
25
26#ifdef __cplusplus
27extern "C" {
28#endif /* __cplusplus */
29
30#include <libexif/exif-mem.h>
31#include <stdarg.h>
32
33/*! State maintained by the logging interface */
34typedef struct _ExifLog        ExifLog;
35
36/*! Create a new logging instance.
37 * \see exif_log_free
38 *
39 * \return new instance of #ExifLog
40 */
41ExifLog *exif_log_new     (void);
42ExifLog *exif_log_new_mem (ExifMem *);
43void     exif_log_ref     (ExifLog *log);
44void     exif_log_unref   (ExifLog *log);
45
46/*! Delete instance of #ExifLog.
47 * \see exif_log_new
48 *
49 * \param[in] log #ExifLog
50 * \return new instance of #ExifLog
51 */
52void     exif_log_free    (ExifLog *log);
53
54typedef enum {
55	EXIF_LOG_CODE_NONE,
56	EXIF_LOG_CODE_DEBUG,
57	EXIF_LOG_CODE_NO_MEMORY,
58	EXIF_LOG_CODE_CORRUPT_DATA
59} ExifLogCode;
60
61/*! Return a textual description of the given class of error log.
62 *
63 * \param[in] code logging message class
64 * \return textual description of the log class
65 */
66const char *exif_log_code_get_title   (ExifLogCode code);
67
68/*! Return a verbose description of the given class of error log.
69 *
70 * \param[in] code logging message class
71 * \return verbose description of the log class
72 */
73const char *exif_log_code_get_message (ExifLogCode code);
74
75/*! Log callback function prototype.
76 */
77typedef void (* ExifLogFunc) (ExifLog *log, ExifLogCode, const char *domain,
78			      const char *format, va_list args, void *data);
79
80/*! Register log callback function.
81 * Calls to the log callback function are purely for diagnostic purposes.
82 *
83 * \param[in] log logging state variable
84 * \param[in] func callback function to set
85 * \param[in] data data to pass into callback function
86 */
87void     exif_log_set_func (ExifLog *log, ExifLogFunc func, void *data);
88
89#ifndef NO_VERBOSE_TAG_STRINGS
90void     exif_log  (ExifLog *log, ExifLogCode, const char *domain,
91		    const char *format, ...)
92#ifdef __GNUC__
93			__attribute__((__format__(printf,4,5)))
94#endif
95;
96#else
97#if defined(__STDC_VERSION__) &&  __STDC_VERSION__ >= 199901L
98#define exif_log(...) do { } while (0)
99#elif defined(__GNUC__)
100#define exif_log(x...) do { } while (0)
101#else
102#define exif_log (void)
103#endif
104#endif
105
106void     exif_logv (ExifLog *log, ExifLogCode, const char *domain,
107		    const char *format, va_list args);
108
109/* For your convenience */
110#define EXIF_LOG_NO_MEMORY(l,d,s) exif_log ((l), EXIF_LOG_CODE_NO_MEMORY, (d), "Could not allocate %lu byte(s).", (unsigned long)(s))
111
112#ifdef __cplusplus
113}
114#endif /* __cplusplus */
115
116#endif /* __EXIF_LOG_H__ */
117