capstone: Update to upstream "next" branch
[qemu.git] / tools / virtiofsd / fuse_log.h
1 /*
2 * FUSE: Filesystem in Userspace
3 * Copyright (C) 2019 Red Hat, Inc.
4 *
5 * This program can be distributed under the terms of the GNU LGPLv2.
6 * See the file COPYING.LIB.
7 */
8
9 #ifndef FUSE_LOG_H_
10 #define FUSE_LOG_H_
11
12 /** @file
13 *
14 * This file defines the logging interface of FUSE
15 */
16
17 #include <stdarg.h>
18
19 /**
20 * Log severity level
21 *
22 * These levels correspond to syslog(2) log levels since they are widely used.
23 */
24 enum fuse_log_level {
25 FUSE_LOG_EMERG,
26 FUSE_LOG_ALERT,
27 FUSE_LOG_CRIT,
28 FUSE_LOG_ERR,
29 FUSE_LOG_WARNING,
30 FUSE_LOG_NOTICE,
31 FUSE_LOG_INFO,
32 FUSE_LOG_DEBUG
33 };
34
35 /**
36 * Log message handler function.
37 *
38 * This function must be thread-safe. It may be called from any libfuse
39 * function, including fuse_parse_cmdline() and other functions invoked before
40 * a FUSE filesystem is created.
41 *
42 * Install a custom log message handler function using fuse_set_log_func().
43 *
44 * @param level log severity level
45 * @param fmt sprintf-style format string including newline
46 * @param ap format string arguments
47 */
48 typedef void (*fuse_log_func_t)(enum fuse_log_level level, const char *fmt,
49 va_list ap);
50
51 /**
52 * Install a custom log handler function.
53 *
54 * Log messages are emitted by libfuse functions to report errors and debug
55 * information. Messages are printed to stderr by default but this can be
56 * overridden by installing a custom log message handler function.
57 *
58 * The log message handler function is global and affects all FUSE filesystems
59 * created within this process.
60 *
61 * @param func a custom log message handler function or NULL to revert to
62 * the default
63 */
64 void fuse_set_log_func(fuse_log_func_t func);
65
66 /**
67 * Emit a log message
68 *
69 * @param level severity level (FUSE_LOG_ERR, FUSE_LOG_DEBUG, etc)
70 * @param fmt sprintf-style format string including newline
71 */
72 void fuse_log(enum fuse_log_level level, const char *fmt, ...);
73
74 #endif /* FUSE_LOG_H_ */