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 /* For logs which have error codes associated with them */
  89 #define flog_err(ferr_id, format, ...)                                        \
  90         zlog_err("[EC %d] " format, ferr_id, ##__VA_ARGS__)
  91 #define flog_err_sys(ferr_id, format, ...)                                     \
  92         flog_err(ferr_id, format, ##__VA_ARGS__)
  93
  94
  95 extern void zlog_thread_info(int log_level);
  96
  97 /* Set logging level for the given destination.  If the log_level
  98    argument is ZLOG_DISABLED, then the destination is disabled.
  99    This function should not be used for file logging (use zlog_set_file
 100    or zlog_reset_file instead). */
 101 extern void zlog_set_level(zlog_dest_t, int log_level);
 102
 103 /* Set logging to the given filename at the specified level. */
 104 extern int zlog_set_file(const char *filename, int log_level);
 105 /* Disable file logging. */
 106 extern int zlog_reset_file(void);
 107
 108 /* Rotate log. */
 109 extern int zlog_rotate(void);
 110
 111 const char *lookup_msg(const struct message *mz, int kz, const char *nf);
 112
 113 /* Safe version of strerror -- never returns NULL. */
 114 extern const char *safe_strerror(int errnum);
 115
 116 /* To be called when a fatal signal is caught. */
 117 extern void zlog_signal(int signo, const char *action
 118 #ifdef SA_SIGINFO
 119                         ,
 120                         siginfo_t *siginfo, void *program_counter
 121 #endif
 122                         );
 123
 124 /* Log a backtrace. */
 125 extern void zlog_backtrace(int priority);
 126
 127 /* Log a backtrace, but in an async-signal-safe way.  Should not be
 128    called unless the program is about to exit or abort, since it messes
 129    up the state of zlog file pointers.  If program_counter is non-NULL,
 130    that is logged in addition to the current backtrace. */
 131 extern void zlog_backtrace_sigsafe(int priority, void *program_counter);
 132
 133 /* Puts a current timestamp in buf and returns the number of characters
 134    written (not including the terminating NUL).  The purpose of
 135    this function is to avoid calls to localtime appearing all over the code.
 136    It caches the most recent localtime result and can therefore
 137    avoid multiple calls within the same second.  If buflen is too small,
 138    *buf will be set to '\0', and 0 will be returned. */
 139 #define QUAGGA_TIMESTAMP_LEN 40
 140 extern size_t quagga_timestamp(int timestamp_precision /* # subsecond digits */,
 141                                char *buf, size_t buflen);
 142
 143 extern void zlog_hexdump(const void *mem, unsigned int len);
 144 extern const char *zlog_sanitize(char *buf, size_t bufsz, const void *in,
 145                                  size_t inlen);
 146
 147
 148 extern int vzlog_test(int priority);
 149
 150 /* structure useful for avoiding repeated rendering of the same timestamp */
 151 struct timestamp_control {
 152         size_t len;                     /* length of rendered timestamp */
 153         int precision;                  /* configuration parameter */
 154         int already_rendered;           /* should be initialized to 0 */
 155         char buf[QUAGGA_TIMESTAMP_LEN]; /* will contain the rendered timestamp
 156                                            */
 157 };
 158
 159 /* Defines for use in command construction: */
 160
 161 #define LOG_LEVEL_DESC                                                         \
 162         "System is unusable\n"                                                 \
 163         "Immediate action needed\n"                                            \
 164         "Critical conditions\n"                                                \
 165         "Error conditions\n"                                                   \
 166         "Warning conditions\n"                                                 \
 167         "Normal but significant conditions\n"                                  \
 168         "Informational messages\n"                                             \
 169         "Debugging messages\n"
 170
 171 #define LOG_FACILITY_DESC                                                      \
 172         "Kernel\n"                                                             \
 173         "User process\n"                                                       \
 174         "Mail system\n"                                                        \
 175         "System daemons\n"                                                     \
 176         "Authorization system\n"                                               \
 177         "Syslog itself\n"                                                      \
 178         "Line printer system\n"                                                \
 179         "USENET news\n"                                                        \
 180         "Unix-to-Unix copy system\n"                                           \
 181         "Cron/at facility\n"                                                   \
 182         "Local use\n"                                                          \
 183         "Local use\n"                                                          \
 184         "Local use\n"                                                          \
 185         "Local use\n"                                                          \
 186         "Local use\n"                                                          \
 187         "Local use\n"                                                          \
 188         "Local use\n"                                                          \
 189         "Local use\n"
 190
 191 #endif /* _ZEBRA_LOG_H */