contrib/xz/src/xz/mytime.c

   1 ///////////////////////////////////////////////////////////////////////////////
   2 //
   3 /// \file       mytime.c
   4 /// \brief      Time handling functions
   5 //
   6 //  Author:     Lasse Collin
   7 //
   8 //  This file has been put into the public domain.
   9 //  You can do whatever you want with this file.
  10 //
  11 ///////////////////////////////////////////////////////////////////////////////
  12
  13 #include "private.h"
  14
  15 #if !(defined(HAVE_CLOCK_GETTIME) && HAVE_DECL_CLOCK_MONOTONIC)
  16 #       include <sys/time.h>
  17 #endif
  18
  19 uint64_t opt_flush_timeout = 0;
  20 bool flush_needed;
  21
  22 static uint64_t start_time;
  23 static uint64_t next_flush;
  24
  25
  26 /// \brief      Get the current time as milliseconds
  27 ///
  28 /// It's relative to some point but not necessarily to the UNIX Epoch.
  29 static uint64_t
  30 mytime_now(void)
  31 {
  32         // NOTE: HAVE_DECL_CLOCK_MONOTONIC is always defined to 0 or 1.
  33 #if defined(HAVE_CLOCK_GETTIME) && HAVE_DECL_CLOCK_MONOTONIC
  34         // If CLOCK_MONOTONIC was available at compile time but for some
  35         // reason isn't at runtime, fallback to CLOCK_REALTIME which
  36         // according to POSIX is mandatory for all implementations.
  37         static clockid_t clk_id = CLOCK_MONOTONIC;
  38         struct timespec tv;
  39         while (clock_gettime(clk_id, &tv))
  40                 clk_id = CLOCK_REALTIME;
  41
  42         return (uint64_t)(tv.tv_sec) * UINT64_C(1000) + tv.tv_nsec / 1000000;
  43 #else
  44         struct timeval tv;
  45         gettimeofday(&tv, NULL);
  46         return (uint64_t)(tv.tv_sec) * UINT64_C(1000) + tv.tv_usec / 1000;
  47 #endif
  48 }
  49
  50
  51 extern void
  52 mytime_set_start_time(void)
  53 {
  54         start_time = mytime_now();
  55         next_flush = start_time + opt_flush_timeout;
  56         flush_needed = false;
  57         return;
  58 }
  59
  60
  61 extern uint64_t
  62 mytime_get_elapsed(void)
  63 {
  64         return mytime_now() - start_time;
  65 }
  66
  67
  68 extern void
  69 mytime_set_flush_time(void)
  70 {
  71         next_flush = mytime_now() + opt_flush_timeout;
  72         flush_needed = false;
  73         return;
  74 }
  75
  76
  77 extern int
  78 mytime_get_flush_timeout(void)
  79 {
  80         if (opt_flush_timeout == 0 || opt_mode != MODE_COMPRESS)
  81                 return -1;
  82
  83         const uint64_t now = mytime_now();
  84         if (now >= next_flush)
  85                 return 0;
  86
  87         const uint64_t remaining = next_flush - now;
  88         return remaining > INT_MAX ? INT_MAX : (int)remaining;
  89 }