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 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 /* Hook for external logging function */
  37 DECLARE_HOOK(zebra_ext_log, (int priority, const char *format, va_list args),
  38              (priority, format, args));
  39
  40 /* Here is some guidance on logging levels to use:
  41  *
  42  * LOG_DEBUG    - For all messages that are enabled by optional debugging
  43  *                features, typically preceded by "if (IS...DEBUG...)"
  44  * LOG_INFO     - Information that may be of interest, but everything seems
  45  *                to be working properly.
  46  * LOG_NOTICE   - Only for message pertaining to daemon startup or shutdown.
  47  * LOG_WARNING  - Warning conditions: unexpected events, but the daemon believes
  48  *                it can continue to operate correctly.
  49  * LOG_ERR      - Error situations indicating malfunctions.  Probably require
  50  *                attention.
  51  *
  52  * Note: LOG_CRIT, LOG_ALERT, and LOG_EMERG are currently not used anywhere,
  53  * please use LOG_ERR instead.
  54  */
  55
  56 /* If maxlvl is set to ZLOG_DISABLED, then no messages will be sent
  57    to that logging destination. */
  58 #define ZLOG_DISABLED   (LOG_EMERG-1)
  59
  60 typedef enum {
  61         ZLOG_DEST_SYSLOG = 0,
  62         ZLOG_DEST_STDOUT,
  63         ZLOG_DEST_MONITOR,
  64         ZLOG_DEST_FILE
  65 } zlog_dest_t;
  66 #define ZLOG_NUM_DESTS          (ZLOG_DEST_FILE+1)
  67
  68 extern bool zlog_startup_stderr;
  69
  70 /* Message structure. */
  71 struct message {
  72         int key;
  73         const char *str;
  74 };
  75
  76 /* Open zlog function */
  77 extern void openzlog(const char *progname, const char *protoname,
  78                      uint16_t instance, int syslog_options,
  79                      int syslog_facility);
  80
  81 /* Close zlog function. */
  82 extern void closezlog(void);
  83
  84 /* GCC have printf type attribute check.  */
  85 #ifdef __GNUC__
  86 #define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b)))
  87 #else
  88 #define PRINTF_ATTRIBUTE(a,b)
  89 #endif /* __GNUC__ */
  90
  91 /* Handy zlog functions. */
  92 extern void zlog_err(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  93 extern void zlog_warn(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  94 extern void zlog_info(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  95 extern void zlog_notice(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  96 extern void zlog_debug(const char *format, ...) PRINTF_ATTRIBUTE(1, 2);
  97 extern void zlog(int priority, const char *format, ...) PRINTF_ATTRIBUTE(2, 3);
  98
  99 /* For logs which have error codes associated with them */
 100 #define flog_err(ferr_id, format, ...)                                        \
 101         zlog_err("[EC %" PRIu32 "] " format, ferr_id, ##__VA_ARGS__)
 102 #define flog_err_sys(ferr_id, format, ...)                                     \
 103         flog_err(ferr_id, format, ##__VA_ARGS__)
 104 #define flog_warn(ferr_id, format, ...)                                        \
 105         zlog_warn("[EC %" PRIu32 "] " format, ferr_id, ##__VA_ARGS__)
 106 #define flog(priority, ferr_id, format, ...)                                   \
 107         zlog(priority, "[EC %" PRIu32 "] " format, ferr_id, ##__VA_ARGS__)
 108
 109 extern void zlog_thread_info(int log_level);
 110
 111 /* Set logging level for the given destination.  If the log_level
 112    argument is ZLOG_DISABLED, then the destination is disabled.
 113    This function should not be used for file logging (use zlog_set_file
 114    or zlog_reset_file instead). */
 115 extern void zlog_set_level(zlog_dest_t, int log_level);
 116
 117 /* Set logging to the given filename at the specified level. */
 118 extern int zlog_set_file(const char *filename, int log_level);
 119 /* Disable file logging. */
 120 extern int zlog_reset_file(void);
 121
 122 /* Rotate log. */
 123 extern int zlog_rotate(void);
 124
 125 const char *lookup_msg(const struct message *mz, int kz, const char *nf);
 126
 127 /* Safe version of strerror -- never returns NULL. */
 128 extern const char *safe_strerror(int errnum);
 129
 130 /* To be called when a fatal signal is caught. */
 131 extern void zlog_signal(int signo, const char *action
 132 #ifdef SA_SIGINFO
 133                         ,
 134                         siginfo_t *siginfo, void *program_counter
 135 #endif
 136                         );
 137
 138 /* Log a backtrace. */
 139 extern void zlog_backtrace(int priority);
 140
 141 /* Log a backtrace, but in an async-signal-safe way.  Should not be
 142    called unless the program is about to exit or abort, since it messes
 143    up the state of zlog file pointers.  If program_counter is non-NULL,
 144    that is logged in addition to the current backtrace. */
 145 extern void zlog_backtrace_sigsafe(int priority, void *program_counter);
 146
 147 /* Puts a current timestamp in buf and returns the number of characters
 148    written (not including the terminating NUL).  The purpose of
 149    this function is to avoid calls to localtime appearing all over the code.
 150    It caches the most recent localtime result and can therefore
 151    avoid multiple calls within the same second.  If buflen is too small,
 152    *buf will be set to '\0', and 0 will be returned. */
 153 #define QUAGGA_TIMESTAMP_LEN 40
 154 extern size_t quagga_timestamp(int timestamp_precision /* # subsecond digits */,
 155                                char *buf, size_t buflen);
 156
 157 extern void zlog_hexdump(const void *mem, unsigned int len);
 158 extern const char *zlog_sanitize(char *buf, size_t bufsz, const void *in,
 159                                  size_t inlen);
 160
 161
 162 extern int vzlog_test(int priority);
 163
 164 /* structure useful for avoiding repeated rendering of the same timestamp */
 165 struct timestamp_control {
 166         size_t len;                     /* length of rendered timestamp */
 167         int precision;                  /* configuration parameter */
 168         int already_rendered;           /* should be initialized to 0 */
 169         char buf[QUAGGA_TIMESTAMP_LEN]; /* will contain the rendered timestamp
 170                                            */
 171 };
 172
 173 /* Defines for use in command construction: */
 174
 175 #define LOG_LEVEL_DESC                                                         \
 176         "System is unusable\n"                                                 \
 177         "Immediate action needed\n"                                            \
 178         "Critical conditions\n"                                                \
 179         "Error conditions\n"                                                   \
 180         "Warning conditions\n"                                                 \
 181         "Normal but significant conditions\n"                                  \
 182         "Informational messages\n"                                             \
 183         "Debugging messages\n"
 184
 185 #define LOG_FACILITY_DESC                                                      \
 186         "Kernel\n"                                                             \
 187         "User process\n"                                                       \
 188         "Mail system\n"                                                        \
 189         "System daemons\n"                                                     \
 190         "Authorization system\n"                                               \
 191         "Syslog itself\n"                                                      \
 192         "Line printer system\n"                                                \
 193         "USENET news\n"                                                        \
 194         "Unix-to-Unix copy system\n"                                           \
 195         "Cron/at facility\n"                                                   \
 196         "Local use\n"                                                          \
 197         "Local use\n"                                                          \
 198         "Local use\n"                                                          \
 199         "Local use\n"                                                          \
 200         "Local use\n"                                                          \
 201         "Local use\n"                                                          \
 202         "Local use\n"                                                          \
 203         "Local use\n"
 204
 205 #ifdef __cplusplus
 206 }
 207 #endif
 208
 209 #endif /* _ZEBRA_LOG_H */