logging.c

   1 #define _GNU_SOURCE /* asprintf */
   2
   3 #include <stdlib.h>
   4 #include <stdarg.h>
   5 #include <stdio.h>
   6 #include <syslog.h>
   7
   8 #include "logging.h"
   9
  10 /* Do we use syslog for messages or stderr? */
  11 int logging = 0;
  12
  13 /* Do we want to silently drop all warnings? */
  14 int quiet = 0;
  15
  16 /* Number of times warn() has been called */
  17 int warned = 0;
  18
  19 /* Do we want informative messages as well as errors? */
  20 int verbose = 0;
  21
  22 void message(const char *prefix, const char *fmt, va_list *arglist)
  23 {
  24         int ret;
  25         char *buf, *buf2;
  26
  27         ret = vasprintf(&buf, fmt, *arglist);
  28         if (ret >= 0)
  29                 ret = asprintf(&buf2, "%s%s", prefix, buf);
  30
  31         if (ret < 0)
  32                 buf2 = "FATAL: Out of memory.\n";
  33
  34         if (logging)
  35                 syslog(LOG_NOTICE, "%s", buf2);
  36         else
  37                 fprintf(stderr, "%s", buf2);
  38
  39         if (ret < 0)
  40                 exit(1);
  41
  42         free(buf2);
  43         free(buf);
  44 }
  45
  46 void warn(const char *fmt, ...)
  47 {
  48         va_list arglist;
  49         warned++;
  50         va_start(arglist, fmt);
  51         if (!quiet)
  52                 message("WARNING: ", fmt, &arglist);
  53         va_end(arglist);
  54 }
  55
  56 void error(const char *fmt, ...)
  57 {
  58         va_list arglist;
  59         va_start(arglist, fmt);
  60         message("ERROR: ", fmt, &arglist);
  61         va_end(arglist);
  62 }
  63
  64 void fatal(const char *fmt, ...)
  65 {
  66         va_list arglist;
  67         va_start(arglist, fmt);
  68         message("FATAL: ", fmt, &arglist);
  69         va_end(arglist);
  70         exit(1);
  71 }
  72
  73 /* If we don't flush, then child processes print before we do */
  74 void info(const char *fmt, ...)
  75 {
  76         va_list arglist;
  77         va_start(arglist, fmt);
  78         if (verbose) {
  79                 vfprintf(stdout, fmt, arglist);
  80                 fflush(stdout);
  81         }
  82         va_end(arglist);
  83 }