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 <stdio.h>
  28
  29 /* Here is some guidance on logging levels to use:
  30  *
  31  * LOG_DEBUG    - For all messages that are enabled by optional debugging
  32  *                features, typically preceded by "if (IS...DEBUG...)"
  33  * LOG_INFO     - Information that may be of interest, but everything seems
  34  *                to be working properly.
  35  * LOG_NOTICE   - Only for message pertaining to daemon startup or shutdown.
  36  * LOG_WARNING  - Warning conditions: unexpected events, but the daemon believes
  37  *                it can continue to operate correctly.
  38  * LOG_ERR      - Error situations indicating malfunctions.  Probably require
  39  *                attention.
  40  *
  41  * Note: LOG_CRIT, LOG_ALERT, and LOG_EMERG are currently not used anywhere,
  42  * please use LOG_ERR instead.
  43  */
  44
  45 /* If maxlvl is set to ZLOG_DISABLED, then no messages will be sent
  46    to that logging destination. */
  47 #define ZLOG_DISABLED   (LOG_EMERG-1)
  48
  49 typedef enum
  50 {
  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 /* Message structure. */
  59 struct message
  60 {
  61   int key;
  62   const char *str;
  63 };
  64
  65 /* Open zlog function */
  66 extern void openzlog (const char *progname, const char *protoname,
  67                       uint16_t instance, int syslog_options, int syslog_facility);
  68
  69 /* Close zlog function. */
  70 extern void closezlog (void);
  71
  72 /* GCC have printf type attribute check.  */
  73 #ifdef __GNUC__
  74 #define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b)))
  75 #else
  76 #define PRINTF_ATTRIBUTE(a,b)
  77 #endif /* __GNUC__ */
  78
  79 /* Handy zlog functions. */
  80 extern void zlog_err (const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  81 extern void zlog_warn (const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  82 extern void zlog_info (const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  83 extern void zlog_notice (const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  84 extern void zlog_debug (const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  85
  86 extern void zlog_thread_info (int log_level);
  87
  88 /* Set logging level for the given destination.  If the log_level
  89    argument is ZLOG_DISABLED, then the destination is disabled.
  90    This function should not be used for file logging (use zlog_set_file
  91    or zlog_reset_file instead). */
  92 extern void zlog_set_level (zlog_dest_t, int log_level);
  93
  94 /* Set logging to the given filename at the specified level. */
  95 extern int zlog_set_file (const char *filename, int log_level);
  96 /* Disable file logging. */
  97 extern int zlog_reset_file (void);
  98
  99 /* Rotate log. */
 100 extern int zlog_rotate (void);
 101
 102 /* For hackey message lookup and check */
 103 #define LOOKUP_DEF(x, y, def) mes_lookup(x, x ## _max, y, def, #x)
 104 #define LOOKUP(x, y) LOOKUP_DEF(x, y, "(no item found)")
 105
 106 extern const char *lookup (const struct message *, int);
 107 extern const char *mes_lookup (const struct message *meslist,
 108                                int max, int index,
 109                                const char *no_item, const char *mesname);
 110
 111 /* Safe version of strerror -- never returns NULL. */
 112 extern const char *safe_strerror(int errnum);
 113
 114 /* To be called when a fatal signal is caught. */
 115 extern void zlog_signal(int signo, const char *action
 116 #ifdef SA_SIGINFO
 117                         , siginfo_t *siginfo, void *program_counter
 118 #endif
 119                        );
 120
 121 /* Log a backtrace. */
 122 extern void zlog_backtrace(int priority);
 123
 124 /* Log a backtrace, but in an async-signal-safe way.  Should not be
 125    called unless the program is about to exit or abort, since it messes
 126    up the state of zlog file pointers.  If program_counter is non-NULL,
 127    that is logged in addition to the current backtrace. */
 128 extern void zlog_backtrace_sigsafe(int priority, void *program_counter);
 129
 130 /* Puts a current timestamp in buf and returns the number of characters
 131    written (not including the terminating NUL).  The purpose of
 132    this function is to avoid calls to localtime appearing all over the code.
 133    It caches the most recent localtime result and can therefore
 134    avoid multiple calls within the same second.  If buflen is too small,
 135    *buf will be set to '\0', and 0 will be returned. */
 136 #define QUAGGA_TIMESTAMP_LEN 40
 137 extern size_t quagga_timestamp(int timestamp_precision /* # subsecond digits */,
 138                                char *buf, size_t buflen);
 139
 140 extern void zlog_hexdump(const void *mem, unsigned int len);
 141 extern const char *zlog_sanitize(char *buf, size_t bufsz, const void *in, size_t inlen);
 142
 143
 144 extern int vzlog_test (int priority);
 145
 146 /* structure useful for avoiding repeated rendering of the same timestamp */
 147 struct timestamp_control {
 148    size_t len;          /* length of rendered timestamp */
 149    int precision;       /* configuration parameter */
 150    int already_rendered; /* should be initialized to 0 */
 151    char buf[QUAGGA_TIMESTAMP_LEN];      /* will contain the rendered timestamp */
 152 };
 153
 154 /* Defines for use in command construction: */
 155
 156 #define LOG_LEVEL_DESC \
 157   "System is unusable\n" \
 158   "Immediate action needed\n" \
 159   "Critical conditions\n" \
 160   "Error conditions\n" \
 161   "Warning conditions\n" \
 162   "Normal but significant conditions\n" \
 163   "Informational messages\n" \
 164   "Debugging messages\n"
 165
 166 #define LOG_FACILITY_DESC \
 167        "Kernel\n" \
 168        "User process\n" \
 169        "Mail system\n" \
 170        "System daemons\n" \
 171        "Authorization system\n" \
 172        "Syslog itself\n" \
 173        "Line printer system\n" \
 174        "USENET news\n" \
 175        "Unix-to-Unix copy system\n" \
 176        "Cron/at facility\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        "Local use\n" \
 184        "Local use\n"
 185
 186 #endif /* _ZEBRA_LOG_H */