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 #include <stdarg.h>
  30 #include "lib/hook.h"
  31
  32 /* Hook for external logging function */
  33 DECLARE_HOOK(zebra_ext_log, (int priority, const char *format, va_list args),
  34              (priority, format, args));
  35
  36 /* Here is some guidance on logging levels to use:
  37  *
  38  * LOG_DEBUG    - For all messages that are enabled by optional debugging
  39  *                features, typically preceded by "if (IS...DEBUG...)"
  40  * LOG_INFO     - Information that may be of interest, but everything seems
  41  *                to be working properly.
  42  * LOG_NOTICE   - Only for message pertaining to daemon startup or shutdown.
  43  * LOG_WARNING  - Warning conditions: unexpected events, but the daemon believes
  44  *                it can continue to operate correctly.
  45  * LOG_ERR      - Error situations indicating malfunctions.  Probably require
  46  *                attention.
  47  *
  48  * Note: LOG_CRIT, LOG_ALERT, and LOG_EMERG are currently not used anywhere,
  49  * please use LOG_ERR instead.
  50  */
  51
  52 /* If maxlvl is set to ZLOG_DISABLED, then no messages will be sent
  53    to that logging destination. */
  54 #define ZLOG_DISABLED   (LOG_EMERG-1)
  55
  56 typedef enum {
  57         ZLOG_DEST_SYSLOG = 0,
  58         ZLOG_DEST_STDOUT,
  59         ZLOG_DEST_MONITOR,
  60         ZLOG_DEST_FILE
  61 } zlog_dest_t;
  62 #define ZLOG_NUM_DESTS          (ZLOG_DEST_FILE+1)
  63
  64 extern bool zlog_startup_stderr;
  65
  66 /* Message structure. */
  67 struct message {
  68         int key;
  69         const char *str;
  70 };
  71
  72 /* Open zlog function */
  73 extern void openzlog(const char *progname, const char *protoname,
  74                      uint16_t instance, int syslog_options,
  75                      int syslog_facility);
  76
  77 /* Close zlog function. */
  78 extern void closezlog(void);
  79
  80 /* GCC have printf type attribute check.  */
  81 #ifdef __GNUC__
  82 #define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b)))
  83 #else
  84 #define PRINTF_ATTRIBUTE(a,b)
  85 #endif /* __GNUC__ */
  86
  87 /* Handy zlog functions. */
  88 extern void zlog_err(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  89 extern void zlog_warn(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  90 extern void zlog_info(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  91 extern void zlog_notice(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  92 extern void zlog_debug(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  93
  94 /* For logs which have error codes associated with them */
  95 #define flog_err(ferr_id, format, ...)                                        \
  96         zlog_err("[EC %"PRIu32"] " format, ferr_id, ##__VA_ARGS__)
  97 #define flog_err_sys(ferr_id, format, ...)                                     \
  98         flog_err(ferr_id, format, ##__VA_ARGS__)
  99 #define flog_warn(ferr_id, format, ...)                                        \
 100         zlog_warn("[EC %"PRIu32"] " format, ferr_id, ##__VA_ARGS__)
 101
 102
 103 extern void zlog_thread_info(int log_level);
 104
 105 /* Set logging level for the given destination.  If the log_level
 106    argument is ZLOG_DISABLED, then the destination is disabled.
 107    This function should not be used for file logging (use zlog_set_file
 108    or zlog_reset_file instead). */
 109 extern void zlog_set_level(zlog_dest_t, int log_level);
 110
 111 /* Set logging to the given filename at the specified level. */
 112 extern int zlog_set_file(const char *filename, int log_level);
 113 /* Disable file logging. */
 114 extern int zlog_reset_file(void);
 115
 116 /* Rotate log. */
 117 extern int zlog_rotate(void);
 118
 119 const char *lookup_msg(const struct message *mz, int kz, const char *nf);
 120
 121 /* Safe version of strerror -- never returns NULL. */
 122 extern const char *safe_strerror(int errnum);
 123
 124 /* To be called when a fatal signal is caught. */
 125 extern void zlog_signal(int signo, const char *action
 126 #ifdef SA_SIGINFO
 127                         ,
 128                         siginfo_t *siginfo, void *program_counter
 129 #endif
 130                         );
 131
 132 /* Log a backtrace. */
 133 extern void zlog_backtrace(int priority);
 134
 135 /* Log a backtrace, but in an async-signal-safe way.  Should not be
 136    called unless the program is about to exit or abort, since it messes
 137    up the state of zlog file pointers.  If program_counter is non-NULL,
 138    that is logged in addition to the current backtrace. */
 139 extern void zlog_backtrace_sigsafe(int priority, void *program_counter);
 140
 141 /* Puts a current timestamp in buf and returns the number of characters
 142    written (not including the terminating NUL).  The purpose of
 143    this function is to avoid calls to localtime appearing all over the code.
 144    It caches the most recent localtime result and can therefore
 145    avoid multiple calls within the same second.  If buflen is too small,
 146    *buf will be set to '\0', and 0 will be returned. */
 147 #define QUAGGA_TIMESTAMP_LEN 40
 148 extern size_t quagga_timestamp(int timestamp_precision /* # subsecond digits */,
 149                                char *buf, size_t buflen);
 150
 151 extern void zlog_hexdump(const void *mem, unsigned int len);
 152 extern const char *zlog_sanitize(char *buf, size_t bufsz, const void *in,
 153                                  size_t inlen);
 154
 155
 156 extern int vzlog_test(int priority);
 157
 158 /* structure useful for avoiding repeated rendering of the same timestamp */
 159 struct timestamp_control {
 160         size_t len;                     /* length of rendered timestamp */
 161         int precision;                  /* configuration parameter */
 162         int already_rendered;           /* should be initialized to 0 */
 163         char buf[QUAGGA_TIMESTAMP_LEN]; /* will contain the rendered timestamp
 164                                            */
 165 };
 166
 167 /* Defines for use in command construction: */
 168
 169 #define LOG_LEVEL_DESC                                                         \
 170         "System is unusable\n"                                                 \
 171         "Immediate action needed\n"                                            \
 172         "Critical conditions\n"                                                \
 173         "Error conditions\n"                                                   \
 174         "Warning conditions\n"                                                 \
 175         "Normal but significant conditions\n"                                  \
 176         "Informational messages\n"                                             \
 177         "Debugging messages\n"
 178
 179 #define LOG_FACILITY_DESC                                                      \
 180         "Kernel\n"                                                             \
 181         "User process\n"                                                       \
 182         "Mail system\n"                                                        \
 183         "System daemons\n"                                                     \
 184         "Authorization system\n"                                               \
 185         "Syslog itself\n"                                                      \
 186         "Line printer system\n"                                                \
 187         "USENET news\n"                                                        \
 188         "Unix-to-Unix copy system\n"                                           \
 189         "Cron/at facility\n"                                                   \
 190         "Local use\n"                                                          \
 191         "Local use\n"                                                          \
 192         "Local use\n"                                                          \
 193         "Local use\n"                                                          \
 194         "Local use\n"                                                          \
 195         "Local use\n"                                                          \
 196         "Local use\n"                                                          \
 197         "Local use\n"
 198
 199 #endif /* _ZEBRA_LOG_H */