lib/log.h

   1 /*
   2  * Zebra logging funcions.
   3  * Copyright (C) 1997, 1998, 1999 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef _ZEBRA_LOG_H
  23 #define _ZEBRA_LOG_H
  24
  25 #include <syslog.h>
  26 #include <stdint.h>
  27 #include <stdbool.h>
  28 #include <stdio.h>
  29
  30 /* Here is some guidance on logging levels to use:
  31  *
  32  * LOG_DEBUG    - For all messages that are enabled by optional debugging
  33  *                features, typically preceded by "if (IS...DEBUG...)"
  34  * LOG_INFO     - Information that may be of interest, but everything seems
  35  *                to be working properly.
  36  * LOG_NOTICE   - Only for message pertaining to daemon startup or shutdown.
  37  * LOG_WARNING  - Warning conditions: unexpected events, but the daemon believes
  38  *                it can continue to operate correctly.
  39  * LOG_ERR      - Error situations indicating malfunctions.  Probably require
  40  *                attention.
  41  *
  42  * Note: LOG_CRIT, LOG_ALERT, and LOG_EMERG are currently not used anywhere,
  43  * please use LOG_ERR instead.
  44  */
  45
  46 /* If maxlvl is set to ZLOG_DISABLED, then no messages will be sent
  47    to that logging destination. */
  48 #define ZLOG_DISABLED   (LOG_EMERG-1)
  49
  50 typedef enum {
  51         ZLOG_DEST_SYSLOG = 0,
  52         ZLOG_DEST_STDOUT,
  53         ZLOG_DEST_MONITOR,
  54         ZLOG_DEST_FILE
  55 } zlog_dest_t;
  56 #define ZLOG_NUM_DESTS          (ZLOG_DEST_FILE+1)
  57
  58 extern bool zlog_startup_stderr;
  59
  60 /* Message structure. */
  61 struct message {
  62         int key;
  63         const char *str;
  64 };
  65
  66 /* Open zlog function */
  67 extern void openzlog(const char *progname, const char *protoname,
  68                      uint16_t instance, int syslog_options,
  69                      int syslog_facility);
  70
  71 /* Close zlog function. */
  72 extern void closezlog(void);
  73
  74 /* GCC have printf type attribute check.  */
  75 #ifdef __GNUC__
  76 #define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b)))
  77 #else
  78 #define PRINTF_ATTRIBUTE(a,b)
  79 #endif /* __GNUC__ */
  80
  81 /* Handy zlog functions. */
  82 extern void zlog_err(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  83 extern void zlog_warn(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  84 extern void zlog_info(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  85 extern void zlog_notice(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  86 extern void zlog_debug(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  87
  88 extern void zlog_thread_info(int log_level);
  89
  90 /* Set logging level for the given destination.  If the log_level
  91    argument is ZLOG_DISABLED, then the destination is disabled.
  92    This function should not be used for file logging (use zlog_set_file
  93    or zlog_reset_file instead). */
  94 extern void zlog_set_level(zlog_dest_t, int log_level);
  95
  96 /* Set logging to the given filename at the specified level. */
  97 extern int zlog_set_file(const char *filename, int log_level);
  98 /* Disable file logging. */
  99 extern int zlog_reset_file(void);
 100
 101 /* Rotate log. */
 102 extern int zlog_rotate(void);
 103
 104 const char *lookup_msg(const struct message *mz, int kz, const char *nf);
 105
 106 /* Safe version of strerror -- never returns NULL. */
 107 extern const char *safe_strerror(int errnum);
 108
 109 /* To be called when a fatal signal is caught. */
 110 extern void zlog_signal(int signo, const char *action
 111 #ifdef SA_SIGINFO
 112                         ,
 113                         siginfo_t *siginfo, void *program_counter
 114 #endif
 115                         );
 116
 117 /* Log a backtrace. */
 118 extern void zlog_backtrace(int priority);
 119
 120 /* Log a backtrace, but in an async-signal-safe way.  Should not be
 121    called unless the program is about to exit or abort, since it messes
 122    up the state of zlog file pointers.  If program_counter is non-NULL,
 123    that is logged in addition to the current backtrace. */
 124 extern void zlog_backtrace_sigsafe(int priority, void *program_counter);
 125
 126 /* Puts a current timestamp in buf and returns the number of characters
 127    written (not including the terminating NUL).  The purpose of
 128    this function is to avoid calls to localtime appearing all over the code.
 129    It caches the most recent localtime result and can therefore
 130    avoid multiple calls within the same second.  If buflen is too small,
 131    *buf will be set to '\0', and 0 will be returned. */
 132 #define QUAGGA_TIMESTAMP_LEN 40
 133 extern size_t quagga_timestamp(int timestamp_precision /* # subsecond digits */,
 134                                char *buf, size_t buflen);
 135
 136 extern void zlog_hexdump(const void *mem, unsigned int len);
 137 extern const char *zlog_sanitize(char *buf, size_t bufsz, const void *in,
 138                                  size_t inlen);
 139
 140
 141 extern int vzlog_test(int priority);
 142
 143 /* structure useful for avoiding repeated rendering of the same timestamp */
 144 struct timestamp_control {
 145         size_t len;                     /* length of rendered timestamp */
 146         int precision;                  /* configuration parameter */
 147         int already_rendered;           /* should be initialized to 0 */
 148         char buf[QUAGGA_TIMESTAMP_LEN]; /* will contain the rendered timestamp
 149                                            */
 150 };
 151
 152 /* Defines for use in command construction: */
 153
 154 #define LOG_LEVEL_DESC                                                         \
 155         "System is unusable\n"                                                 \
 156         "Immediate action needed\n"                                            \
 157         "Critical conditions\n"                                                \
 158         "Error conditions\n"                                                   \
 159         "Warning conditions\n"                                                 \
 160         "Normal but significant conditions\n"                                  \
 161         "Informational messages\n"                                             \
 162         "Debugging messages\n"
 163
 164 #define LOG_FACILITY_DESC                                                      \
 165         "Kernel\n"                                                             \
 166         "User process\n"                                                       \
 167         "Mail system\n"                                                        \
 168         "System daemons\n"                                                     \
 169         "Authorization system\n"                                               \
 170         "Syslog itself\n"                                                      \
 171         "Line printer system\n"                                                \
 172         "USENET news\n"                                                        \
 173         "Unix-to-Unix copy system\n"                                           \
 174         "Cron/at facility\n"                                                   \
 175         "Local use\n"                                                          \
 176         "Local use\n"                                                          \
 177         "Local use\n"                                                          \
 178         "Local use\n"                                                          \
 179         "Local use\n"                                                          \
 180         "Local use\n"                                                          \
 181         "Local use\n"                                                          \
 182         "Local use\n"
 183
 184 #endif /* _ZEBRA_LOG_H */