include/minix/log.h

   1 #ifndef __LOG_H__
   2 #define __LOG_H__
   3 /*
   4  * Simple logging functions
   5  */
   6
   7 #include <stdarg.h>
   8
   9 /*
  10  * LEVEL_NONE  do not log anything.
  11  * LEVEL_WARN  Information that needs to be known.
  12  * LEVEL_INFO  Basic information like startup messages and occasional events.
  13  * LEVEL_DEBUG debug statements about things happening that are less expected.
  14  * LEVEL_TRACE Way to much information for anybody.
  15  */
  16
  17 #define LEVEL_NONE 0
  18 #define LEVEL_WARN 1
  19 #define LEVEL_INFO 2
  20 #define LEVEL_DEBUG 3
  21 #define LEVEL_TRACE 4
  22
  23 static const char *level_string[5] = {
  24         "none",
  25         "warn",
  26         "info",
  27         "debug",
  28         "trace"
  29 };
  30
  31 /*
  32  * struct to be initialized by the user of the logging system.
  33  *
  34  * name: The name attribute is used in logging statements do differentiate
  35  * drivers
  36  *
  37  * log_level The level attribute describes the requested logging level. a level
  38  * of 1 will only print warnings while a level of 4 will print all the trace
  39  * information.
  40  *
  41  * log_func The logging function to use to log, log.h provides default_log
  42  * to display information on the kernel output buffer. As a bonus if the
  43  * requested log level is debug or trace the method , file and line number will
  44  * be printed to the steam.
  45  */
  46 struct log
  47 {
  48         const char *name;
  49         int log_level;
  50
  51         /* the logging function itself */
  52         void (*log_func) (struct log * driver,
  53             int level,
  54             const char *file,
  55             const char *function, int line, const char *fmt, ...);
  56
  57 };
  58
  59 #define __log(driver,log_level, fmt, args...) \
  60                 ((driver)->log_func(driver,log_level, \
  61                                 __FILE__, __FUNCTION__, __LINE__,\
  62                                 fmt, ## args))
  63
  64 /* Log a warning */
  65 #define log_warn(driver, fmt, args...) \
  66                 __log(driver, LEVEL_WARN, fmt, ## args)
  67
  68 /* Log an information message  */
  69 #define log_info(driver, fmt, args...) \
  70                 __log(driver, LEVEL_INFO, fmt, ## args)
  71
  72 /* log debugging output  */
  73 #define log_debug(driver, fmt, args...) \
  74                 __log(driver, LEVEL_DEBUG, fmt, ## args)
  75
  76 /* log trace output  */
  77 #define log_trace(driver, fmt, args...) \
  78                 __log(driver, LEVEL_TRACE, fmt, ## args)
  79
  80 #endif /* __LOG_H__ */
  81
  82 static void
  83 default_log(struct log *driver,
  84     int level,
  85     const char *file, const char *function, int line, const char *fmt, ...)
  86 {
  87         va_list args;
  88
  89         if (level > driver->log_level) {
  90                 return;
  91         }
  92         /* If the wanted level is debug also display line/method information */
  93         if (driver->log_level >= LEVEL_DEBUG) {
  94                 printf("%s(%s):%s+%d(%s):", driver->name,
  95                     level_string[level], file, line, function);
  96         } else {
  97                 printf("%s(%s)", driver->name, level_string[level]);
  98         }
  99
 100         va_start(args, fmt);
 101         vprintf(fmt, args);
 102         va_end(args);
 103 }
 104
 105 #ifdef hacks
 106 static void
 107 hexdump(unsigned char *d, unsigned int size)
 108 {
 109         int s;
 110         for (s = 0; s < size; s += 4) {
 111                 fprintf(stdout, "0x%04x 0x%02X%02X%02X%02X %c%c%c%c\n", s,
 112                     (unsigned int) d[s], (unsigned int) d[s + 1],
 113                     (unsigned int) d[s + 2], (unsigned int) d[s + 3], d[s],
 114                     d[s + 1], d[s + 2], d[s + 3]);
 115         }
 116 }
 117 #endif