LXR qemu/tools/virtiofsd/fuse

   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
  18/**
  19 * Log severity level
  20 *
  21 * These levels correspond to syslog(2) log levels since they are widely used.
  22 */
  23enum fuse_log_level {
  24    FUSE_LOG_EMERG,
  25    FUSE_LOG_ALERT,
  26    FUSE_LOG_CRIT,
  27    FUSE_LOG_ERR,
  28    FUSE_LOG_WARNING,
  29    FUSE_LOG_NOTICE,
  30    FUSE_LOG_INFO,
  31    FUSE_LOG_DEBUG
  32};
  33
  34/**
  35 * Log message handler function.
  36 *
  37 * This function must be thread-safe.  It may be called from any libfuse
  38 * function, including fuse_parse_cmdline() and other functions invoked before
  39 * a FUSE filesystem is created.
  40 *
  41 * Install a custom log message handler function using fuse_set_log_func().
  42 *
  43 * @param level log severity level
  44 * @param fmt sprintf-style format string including newline
  45 * @param ap format string arguments
  46 */
  47typedef void (*fuse_log_func_t)(enum fuse_log_level level, const char *fmt,
  48                                va_list ap);
  49
  50/**
  51 * Install a custom log handler function.
  52 *
  53 * Log messages are emitted by libfuse functions to report errors and debug
  54 * information.  Messages are printed to stderr by default but this can be
  55 * overridden by installing a custom log message handler function.
  56 *
  57 * The log message handler function is global and affects all FUSE filesystems
  58 * created within this process.
  59 *
  60 * @param func a custom log message handler function or NULL to revert to
  61 *             the default
  62 */
  63void fuse_set_log_func(fuse_log_func_t func);
  64
  65/**
  66 * Emit a log message
  67 *
  68 * @param level severity level (FUSE_LOG_ERR, FUSE_LOG_DEBUG, etc)
  69 * @param fmt sprintf-style format string including newline
  70 */
  71void fuse_log(enum fuse_log_level level, const char *fmt, ...);
  72
  73#endif /* FUSE_LOG_H_ */
  74