libutil/Log.cc

   1 /* Put log messages either to stdout or syslog.
   2  *
   3  * Assimilated from git.git::daemon.c on 2007-05-19. */
   4
   5 #include <sys/types.h>
   6 #include <unistd.h>
   7 #include <time.h>
   8 #include <string.h>
   9
  10 #include "libutil/Log.h"
  11
  12 namespace remote { namespace util {
  13
  14 void
  15 Log::open(const char *ident, int level, FILE *file)
  16 {
  17         if (use_syslog()) {
  18                 closelog();
  19         }
  20
  21         log_ident = ident;
  22         log_level = level;
  23         log_file = file;
  24
  25         if (use_syslog()) {
  26                 openlog(log_ident, 0, LOG_DAEMON);
  27         }
  28 }
  29
  30 void
  31 Log::put(int priority, const char *format, va_list params)
  32 {
  33         /* We should do a single write so that it is atomic and output
  34          * of several processes do not get intermingled. */
  35         char buf[1024];
  36         int buflen;
  37         int maxlen, msglen;
  38         time_t t;
  39         char *timestr;
  40
  41         if (ignore(priority))
  42                 return;
  43
  44         /* sizeof(buf) should be big enough for "[pid] \n" */
  45         buflen = snprintf(buf, sizeof(buf), "[%ld] ", (long) getpid());
  46
  47         maxlen = sizeof(buf) - buflen - 1; /* -1 for our own LF */
  48         msglen = vsnprintf(buf + buflen, maxlen, format, params);
  49
  50         if (use_syslog()) {
  51                 syslog(priority, "%s", buf);
  52                 return;
  53         }
  54
  55         /* maxlen counted our own LF but also counts space given to
  56          * vsnprintf for the terminating NUL.  We want to make sure that
  57          * we have space for our own LF and NUL after the "meat" of the
  58          * message, so truncate it at maxlen - 1.
  59          */
  60         if (msglen > maxlen - 1)
  61                 msglen = maxlen - 1;
  62         else if (msglen < 0)
  63                 msglen = 0; /* Protect against weird return values. */
  64         buflen += msglen;
  65
  66         buf[buflen] = '\0';
  67
  68         time(&t);
  69         timestr = ctime(&t);
  70         fprintf(log_file, "%s - %s %s\n", strsep(&timestr, "\n"), log_ident, buf);
  71 }
  72
  73 void
  74 Log::error(const char *format, ...)
  75 {
  76         va_list params;
  77
  78         va_start(params, format);
  79         put(LOG_ERR, format, params);
  80         va_end(params);
  81 }
  82
  83 void
  84 Log::warn(const char *format, ...)
  85 {
  86         va_list params;
  87
  88         va_start(params, format);
  89         put(LOG_WARNING, format, params);
  90         va_end(params);
  91 }
  92
  93 void
  94 Log::info(const char *format, ...)
  95 {
  96         va_list params;
  97
  98         va_start(params, format);
  99         put(LOG_INFO, format, params);
 100         va_end(params);
 101 }
 102
 103 void
 104 Log::debug(const char *format, ...)
 105 {
 106         va_list params;
 107
 108         va_start(params, format);
 109         put(LOG_DEBUG, format, params);
 110         va_end(params);
 111 }
 112
 113 const char *Log::log_ident;
 114 FILE *Log::log_file;
 115 int Log::log_level;
 116
 117 }}