logging.h

   1 /*
   2  * logging.h
   3  *
   4  * Simple logging functions that can be compiled away into nothing.
   5  *
   6  * Copyright (C) 2003,2004 Greg Kroah-Hartman <greg@kroah.com>
   7  * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
   8  *
   9  *      This program is free software; you can redistribute it and/or modify it
  10  *      under the terms of the GNU General Public License as published by the
  11  *      Free Software Foundation version 2 of the License.
  12  *
  13  *      This program is distributed in the hope that it will be useful, but
  14  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *      General Public License for more details.
  17  *
  18  *      You should have received a copy of the GNU General Public License along
  19  *      with this program; if not, write to the Free Software Foundation, Inc.,
  20  *      675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  */
  23
  24 #ifndef LOGGING_H
  25 #define LOGGING_H
  26
  27 #define info(format, arg...)            do { } while (0)
  28 #define dbg(format, arg...)             do { } while (0)
  29 #define dbg_parse(format, arg...)       do { } while (0)
  30 #define init_logging(foo)               do { } while (0)
  31
  32 #ifdef LOG
  33 #include <stdarg.h>
  34 #include <unistd.h>
  35 #include <syslog.h>
  36
  37 #undef info
  38 #define info(format, arg...)                                                            \
  39         do {                                                                            \
  40                 log_message (LOG_INFO , format , ## arg);                               \
  41         } while (0)
  42
  43 #ifdef DEBUG
  44 #undef dbg
  45 #define dbg(format, arg...)                                                             \
  46         do {                                                                            \
  47                 log_message (LOG_DEBUG , "%s: " format , __FUNCTION__ , ## arg);        \
  48         } while (0)
  49 #endif
  50
  51 /* Parser needs it's own debugging statement, we usually don't care about this at all */
  52 #ifdef DEBUG_PARSER
  53 #undef dbg_parse
  54 #define dbg_parse(format, arg...)                                                       \
  55         do {                                                                            \
  56                 log_message (LOG_DEBUG , "%s: " format , __FUNCTION__ , ## arg);        \
  57         } while (0)
  58 #endif
  59
  60 /* each program must declare this variable and function somewhere */
  61 extern unsigned char logname[42];
  62 extern int log_ok(void);
  63
  64 static void log_message (int level, const char *format, ...)
  65         __attribute__ ((format (printf, 2, 3)));
  66 static inline void log_message (int level, const char *format, ...)
  67 {
  68         va_list args;
  69
  70         if (!log_ok())
  71                 return;
  72
  73         va_start(args, format);
  74         vsyslog(level, format, args);
  75         va_end(args);
  76 }
  77
  78 #undef init_logging
  79 static inline void init_logging(char *program_name)
  80 {
  81         snprintf(logname, 42,"%s[%d]", program_name, getpid());
  82         openlog(logname, 0, LOG_DAEMON);
  83 }
  84
  85 #endif  /* LOG */
  86
  87 #endif