src/common.c

   1 #ifndef COMMON_C
   2 #define COMMON_C
   3
   4 #include "config.h"
   5
   6 #include <stdio.h>
   7 #include <netdb.h>
   8 #include <stdarg.h>
   9 #include <errno.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <time.h>
  13 #include <unistd.h>
  14 #include <arpa/inet.h>
  15 #include <netinet/in.h>
  16
  17 #include "common.h"
  18
  19
  20 #ifndef OPT_RULEPARSER_TEST
  21 /* globals */
  22 static int loglevel = LOGMSG_ERR; /* the default logging level is to only log error messages */
  23 static char logfilename[4096]; /* name of file to which log messages should be redirected */
  24 static FILE *logfile = NULL; /* file to which messages should be logged */
  25 static int logstamp = 0; /* timestamp (and pid stamp) messages */
  26
  27
  28 /* Set logging options, the options are as follows:             */
  29 /*  level - This sets the logging threshold, messages with      */
  30 /*          a higher level (i.e lower importance) will not be   */
  31 /*          output. For example, if the threshold is set to     */
  32 /*          MSGWARN a call to log a message of level MSGDEBUG   */
  33 /*          would be ignored. This can be set to -1 to disable  */
  34 /*          messages entirely                                   */
  35 /*  filename - This is a filename to which the messages should  */
  36 /*             be logged instead of to standard error           */
  37 /*  timestamp - This indicates that messages should be prefixed */
  38 /*              with timestamps (and the process id)            */
  39 static void setLogOptions (int level, const char *filename, int timestamp) {
  40   loglevel = level;
  41   if (loglevel < LOGMSG_ERR) loglevel = LOGMSG_NONE;
  42   if (filename) {
  43     strncpy(logfilename, filename, sizeof(logfilename));
  44     logfilename[sizeof(logfilename)-1] = '\0';
  45   }
  46   logstamp = timestamp;
  47 }
  48
  49
  50 static void logMsg (int level, const char *fmt, ...) {
  51   va_list ap;
  52   int saveerr;
  53   extern char *progname;
  54   char timestring[20];
  55   time_t timestamp;
  56
  57   if (loglevel == LOGMSG_NONE || level > loglevel) return;
  58
  59   saveerr = errno;
  60
  61   if (!logfile) {
  62     if (logfilename[0]) {
  63       logfile = fopen(logfilename, "a");
  64       if (logfile == NULL) {
  65         logfile = stderr;
  66         logMsg(LOGMSG_ERR, "could not open log file, %s, %s\n", logfilename, strerror(errno));
  67       }
  68     } else logfile = stderr;
  69   }
  70
  71   if (logstamp) {
  72     timestamp = time(NULL);
  73     strftime(timestring, sizeof(timestring), "%H:%M:%S", localtime(&timestamp));
  74     fprintf(logfile, "%s ", timestring);
  75   }
  76
  77   fputs(progname, logfile);
  78   if (logstamp) {
  79     fprintf(logfile, "(%d)[%s]", getpid(), getProcName());
  80   }
  81
  82   fputs(": ", logfile);
  83   va_start(ap, fmt);
  84   vfprintf(logfile, fmt, ap);
  85   va_end(ap);
  86   fflush(logfile);
  87
  88   errno = saveerr;
  89 }
  90
  91 #else
  92
  93 static void logMsg (int level, const char *fmt, ...) {
  94   va_list ap;
  95   int saveerr;
  96
  97   saveerr = errno;
  98
  99   fprintf(stderr, "[%s] ", getProcName());
 100   va_start(ap, fmt);
 101   vfprintf(stderr, fmt, ap);
 102   va_end(ap);
 103   fflush(stderr);
 104
 105   errno = saveerr;
 106 }
 107
 108 #endif
 109
 110
 111 static char *getProcName (void) {
 112   static char name[4096] = {0};
 113   char buf[512];
 114
 115   if (name[0]) return name;
 116   pid_t pid = getpid();
 117   sprintf(buf, "/proc/%u/exe", pid);
 118   ssize_t len = readlink(buf, name, sizeof(name));
 119   if (len < 1) strcpy(name, "<unknown>"); else name[len] = 0;
 120   return name;
 121 }
 122
 123
 124 #endif