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 /* Do we want informative messages as well as errors? */
  17 int verbose = 0;
  18
  19 void message(const char *prefix, const char *fmt, va_list *arglist)
  20 {
  21         int ret;
  22         char *buf, *buf2;
  23
  24         ret = vasprintf(&buf, fmt, *arglist);
  25         if (ret >= 0)
  26                 ret = asprintf(&buf2, "%s%s", prefix, buf);
  27
  28         if (ret < 0)
  29                 buf2 = "FATAL: Out of memory.\n";
  30
  31         if (logging)
  32                 syslog(LOG_NOTICE, "%s", buf2);
  33         else
  34                 fprintf(stderr, "%s", buf2);
  35
  36         if (ret < 0)
  37                 exit(1);
  38
  39         free(buf2);
  40         free(buf);
  41 }
  42
  43 void warn(const char *fmt, ...)
  44 {
  45         va_list arglist;
  46         va_start(arglist, fmt);
  47         if (!quiet)
  48                 message("WARNING: ", fmt, &arglist);
  49         va_end(arglist);
  50 }
  51
  52 void error(const char *fmt, ...)
  53 {
  54         va_list arglist;
  55         va_start(arglist, fmt);
  56         message("ERROR: ", fmt, &arglist);
  57         va_end(arglist);
  58 }
  59
  60 void fatal(const char *fmt, ...)
  61 {
  62         va_list arglist;
  63         va_start(arglist, fmt);
  64         message("FATAL: ", fmt, &arglist);
  65         va_end(arglist);
  66         exit(1);
  67 }
  68
  69 /* If we don't flush, then child processes print before we do */
  70 void info(const char *fmt, ...)
  71 {
  72         va_list arglist;
  73         va_start(arglist, fmt);
  74         if (verbose) {
  75                 vfprintf(stdout, fmt, arglist);
  76                 fflush(stdout);
  77         }
  78         va_end(arglist);
  79 }