From 1eee6366bbaa10a34232046fee3aa83181bc452f Mon Sep 17 00:00:00 2001
From: beware <beware@bircd.org>
Date: Sun, 5 Oct 2025 20:40:45 +0000
Subject: [PATCH] btime overhaul. newer APIs. added btime_gettime. now requires
 int64.

---
 btime.pas         | 814 +++++++++++++++++++++++++++++++++-------------
 ltimevalstuff.pas |  12 +-
 unixstuff.inc     |   4 +-
 3 files changed, 602 insertions(+), 228 deletions(-)

diff --git a/btime.pas b/btime.pas
index 4052493..6ee3dbb 100644
--- a/btime.pas
+++ b/btime.pas
@@ -3,8 +3,28 @@
   which is included in the package
   ----------------------------------------------------------------------------- }
 {
-this unit returns unix timestamp with seconds and microseconds (as float)
-works on windows/delphi, and on freepascal on unix.
+this unit has several functions for getting unix and monotonic time and UTC offset on both windows and linux/unix
+
+this unit aims to work on delphi 6 and later, both x86 and x64, on win95 and later
+delphi 5 may work (untested).
+as well as freepascal on linux x86 and x64 and freebsd x64 (tested), windows, and other unixes (untested)
+
+provided functions. all are available on both windows and linux/unix:
+- unix timestamp as a (double or extended) float or integer: unixtimefloat, unixtimeint
+- monotonic timestamp as float: monotimefloat, wintimefloat (both are equivalent)
+- _coarse versions of the floats, which can be faster, and precision in the milliseconds.
+- btime_gettime: a unified function like clock_gettime. less reliant on floats.
+- tzgetoffset returns the UTC offset (timezone) in seconds
+
+- on windows, it provides the legacy function gettimeofday (on unix, use the one provided by the OS units)
+
+other things in the interface are often more implementation specific, there for legacy reasons, and not guaranteed stable
+
+this unit should be 2038 safe:
+- seconds are handled as 64 bits
+- on 32 bits linux, it uses clock_gettime64 if available 
+- for getting the UTC offset on unix, this unit does its own, 64 bits aware, parsing of the zoneinfo file 
+- tested with clock set after 2038
 }
 
 
@@ -20,22 +40,92 @@ interface
 {$ifdef mswindows}
 uses
   ltimevalstuff;
-{$endif}  
+{$endif}
+
+{$ifdef linux}
+uses
+  linux,syscall;
+{$endif}
+
+{$ifdef freebsd}
+uses
+  freebsd;
+{$endif}
+
+{$ifdef FPC_HAS_TYPE_EXTENDED}{$define has_extended}{$endif}
+{$ifndef fpc}{$ifdef cpu386}{$define has_extended}{$endif}{$endif}
 
 type
+  {$ifdef has_extended}
   float=extended;
-  tunixtimeint={$ifdef ver100}longint;{$else}int64;{$endif}
+  {$else}
+  float=double;
+  {$endif}
+  tunixtimeint=int64;
 
 const
   colorburst=39375000/11;  {3579545.4545....}
 
+  {
+  CLOCK_MONOTONIC is the standard monotonic time offered by the OS, it may or may not include suspend time
+  CLOCK_BOOTTIME includes suspend time.
+  CLOCK_UPTIME excludes suspend time.
+  }
+
+  {$ifdef mswindows}
+  CLOCK_REALTIME=0;
+  CLOCK_MONOTONIC=1;
+  CLOCK_REALTIME_COARSE=2;
+  CLOCK_MONOTONIC_COARSE=3;
+  CLOCK_BOOTTIME=CLOCK_MONOTONIC;  //GetTickCount
+  CLOCK_UPTIME=4;                  //QueryUnbiasedInterruptTime, fallback to QueryPerformanceCounter
+  CLOCK_UPTIME_FAST=CLOCK_UPTIME;
+  {$endif}
+
+  {$ifdef linux}
+  CLOCK_REALTIME=linux.CLOCK_REALTIME;
+  CLOCK_MONOTONIC=linux.CLOCK_MONOTONIC;
+  CLOCK_REALTIME_COARSE=linux.CLOCK_REALTIME_COARSE;
+  CLOCK_MONOTONIC_COARSE=linux.CLOCK_MONOTONIC_COARSE;
+  CLOCK_BOOTTIME=7; //linux.CLOCK_BOOTTIME - constant missing in freepascal
+  CLOCK_UPTIME=CLOCK_MONOTONIC;
+  CLOCK_UPTIME_FAST=CLOCK_MONOTONIC_COARSE;
+  {$endif}
+
+  {$ifdef freebsd}
+  CLOCK_REALTIME=freebsd.CLOCK_REALTIME;
+  CLOCK_MONOTONIC=freebsd.CLOCK_MONOTONIC;
+  CLOCK_REALTIME_COARSE=freebsd.CLOCK_REALTIME_FAST;
+  CLOCK_MONOTONIC_COARSE=freebsd.CLOCK_MONOTONIC_FAST;
+  CLOCK_BOOTTIME=CLOCK_MONOTONIC;
+  CLOCK_UPTIME=freebsd.CLOCK_UPTIME;
+  CLOCK_UPTIME_FAST=freebsd.CLOCK_UPTIME_FAST;
+  {$endif}
+
+  {$ifdef darwin}
+  CLOCK_REALTIME=0;      //values taken from darwin libc time.h
+  CLOCK_MONOTONIC=6;
+  CLOCK_REALTIME_COARSE=CLOCK_REALTIME;   //darwin lacks these or equivalents
+  CLOCK_MONOTONIC_COARSE=CLOCK_MONOTONIC;
+  CLOCK_BOOTTIME=CLOCK_MONOTONIC;
+  CLOCK_UPTIME_RAW=8;
+  CLOCK_UPTIME=CLOCK_UPTIME_RAW;
+  CLOCK_UPTIME_FAST=CLOCK_UPTIME_RAW;
+  {$endif}
+
+  CLOCK_REALTIME_FAST=CLOCK_REALTIME_COARSE;
+  CLOCK_MONOTONIC_FAST=CLOCK_MONOTONIC_COARSE;
+
+
 var
   timezone:integer;
   timezonestr:string;
   irctime,unixtime:tunixtimeint;
   tickcount:integer;
   settimebias:tunixtimeint;
-  performancecountfreq:extended;
+  performancecountfreq:int64;
+  performancecountstep:float;
+
   btimenowin8:boolean;
 
 function irctimefloat:float;
@@ -48,9 +138,20 @@ function unixtimeint:tunixtimeint;
 //monotonic float seconds
 function monotimefloat:float;
 
+//coarse float seconds - usually faster, but a resolution in the milliseconds
+function unixtimefloat_coarse:float;
+function monotimefloat_coarse:float;
+
+//float versions of CLOCK_BOOTTIME and CLOCK_UPTIME
+function boottimefloat:float;
+function uptimefloat:float;
+
 //monotonic (alias, old function name)
 function wintimefloat:float;
 
+//get localtime vs UTC offset in seconds
+function tzgetoffset:integer;
+
 procedure settime(newtime:tunixtimeint);
 procedure gettimezone;
 procedure timehandler;
@@ -80,11 +181,12 @@ function unixtoole(i:float):tdatetime;
 
 {$ifdef mswindows}
 function mmtimefloat:float;
+function mmtimeint64:int64;
 function qpctimefloat:float;
 {$endif}
 
 {$ifdef mswindows}
-procedure gettimeofday(var tv:ttimeval);
+function gettimeofday(var tv:ttimeval):integer;
 {$endif}
 
 
@@ -105,7 +207,7 @@ var
   lastsyncbias:float=0;
 
   mmtime_last:integer=0;
-  mmtime_wrapadd:float;
+  mmtime_wrapadd:int64;
   mmtime_lastsyncmm:float=0;
   mmtime_lastsyncqpc:float=0;
   mmtime_drift:float=1;
@@ -118,17 +220,29 @@ var
   mmtime_prev_lastsyncmm:float;
   mmtime_prev_lastsyncqpc:float;
 
-implementation
+  gettime64_nosupport_cached:boolean;
+  coarse_nosupport_cached:boolean;
 
+type
+  //i define my own "timespec" and "gettime" because that way, they can be 64 bits even if the real one is 32 bits, and avoid the wrong one being used.
+  //tbtimespec can't be changed because it is passed as-is to clock_gettime64
+  tbtimespec=packed record
+    tv_sec:int64;
+    tv_nsec:int64;
+  end;
+  pbtimespec=^tbtimespec;
 
 
+//on unix, btime_gettime is the "inner" function that calls the actual OS/library functions, and other functions in btime call it
+//on windows, btime_gettime is an "outer" function that calls the other functions. so if not called by the app, it does not add to exe size.
+function btime_gettime(clockid:integer;tp:pbtimespec):integer;
+
+implementation
 uses
   {$ifdef UNIX}
     {$ifdef VER1_0}
       linux,
     {$else}
-      {$ifdef linux}linux,{$endif} //for clock_gettime
-      {$ifdef freebsd}freebsd,{$endif} //for clock_gettime
       baseunix,unix,unixutil,sockets, {unixutil and sockets needed by unixstuff.inc on some compiler versions}
     {$endif}
   {$else}
@@ -158,117 +272,204 @@ begin
   result := ((i)/86400)+daysdifference;
 end;
 
-const
-  highdwordconst=65536.0 * 65536.0;
-
-function utrunc(f:float):integer;
-{converts float to integer, in 32 bits unsigned range}
-begin
-  if f >= (highdwordconst/2) then f := f - highdwordconst;
-  result := trunc(f);
-end;
-
-function uinttofloat(i:integer):float;
-{converts 32 bits unsigned integer to float}
-begin
-  result := i;
-  if result < 0 then result := result + highdwordconst;
-end;
-
 {$ifdef unix}
 {-----------------------------------------*nix/freepascal code to read time }
 
-function unixtimefloat:float;
-var
-  tv:ttimeval;
-  sec:tunixtimeint;
-begin
-  gettimeofday(tv);
-  sec := tv.tv_sec;
-  {$ifndef cpu64}
-  if (sec < -1) then inc(sec,$100000000); //tv_sec is 32 bits. allow -1 for invalid result
-  {$endif}
-  result := sec+(tv.tv_usec/1000000);
-end;
-
 {$ifdef linux}{$define have_clock_gettime}{$endif}
 {$ifdef freebsd}{$define have_clock_gettime}{$endif}
 
-{$ifdef have_clock_gettime}
-  {$define monotimefloat_implemented}
+{$ifdef linux}
+  {$ifdef cpu386}{$define use_syscall_gettime64}{$endif}
+  {$ifdef cpu32}{$define use_syscall_gettime64}{$endif}
 
-  function monotimefloat:float;
-  var
-    ts: ttimespec;
-  begin
-    if clock_gettime(CLOCK_MONOTONIC, @ts) = 0 then begin
-      //note this really returns nanoseconds
-      result := ts.tv_sec + ts.tv_nsec / 1000000000.0;
-      exit;
-    end;
-    //fallback
-    result := unixtimefloat;
-  end;
+  {$ifdef use_syscall_gettime64}
+const
+  clock_gettime64=403;
+  {$endif}
+{$endif} //linux
 
 
-{$endif}
 
 {$ifdef darwin} {mac OS X}
-{$define monotimefloat_implemented}
-
   type
     tmach_timebase_info = packed record
-      numer: longint;
-      denom: longint;
+      numer: cardinal;
+      denom: cardinal;
     end;
     pmach_timebase_info = ^tmach_timebase_info;
-     
+
     function mach_absolute_time: int64; cdecl; external;
     function mach_timebase_info(info: pmach_timebase_info): integer; cdecl; external;
 
   var
     timebase_info: tmach_timebase_info;
+{$endif} //darwin
 
-  function monotimefloat:float;
-  var
-    i:int64;
-  begin
+
+function btime_gettime(clockid:integer;tp:pbtimespec):integer;
+var
+{$ifdef have_clock_gettime}
+  ts: ttimespec;
+{$endif}
+  tv: ttimeval;
+{$ifdef darwin}
+  nanos:int64;
+  nanosf:extended;
+{$endif}
+
+begin
+  result := -1; //error
+
+  {$ifdef darwin}
+  if (clockid = CLOCK_MONOTONIC) or (clockid = CLOCK_MONOTONIC_COARSE) then begin
     if timebase_info.denom = 0 then begin
       mach_timebase_info(@timebase_info);
     end;
-    i := mach_absolute_time;
-    result := (i * timebase_info.numer div timebase_info.denom) / 1000000000.0;
+    if (timebase_info.denom > 0) then begin
+      nanos := mach_absolute_time;
+      if (nanos > 0) then begin
+        result := 0; //indicate success
+        if (timebase_info.denom > 10) then begin
+          //on powerpc mac, numer and denom are large numbers such as 1000000000 and 33333335, and extended is available
+          nanosf := nanos;
+          nanosf := (nanosf * timebase_info.numer) / timebase_info.denom;
+          nanos := trunc(nanosf);
+        end else begin
+          //on intel mac, numer and denom are 1 and 1. on apple silicon they are typically 125 and 3, and extended is not available
+          nanos := nanos div timebase_info.denom;
+          nanos := nanos * timebase_info.numer;
+        end;
+        tp.tv_sec := nanos div 1000000000;
+        tp.tv_nsec := nanos mod 1000000000;
+        exit;
+      end;
+    end;
   end;
+  {$endif} //darwin
 
-{$endif} {darwin, mac OS X}
+  if (coarse_nosupport_cached) then begin
+    if (clockid = CLOCK_REALTIME_COARSE) then clockid := CLOCK_REALTIME;
+    if (clockid = CLOCK_MONOTONIC_COARSE) then clockid := CLOCK_MONOTONIC;
+  end;
 
+  {$ifdef use_syscall_gettime64}
+  //don't do this for monotonic for performance reasons
+  //the clock_gettime call below has the potential to be handled by libc, and then it is faster
+  //also if it failed, don't call it again to avoid slowdown of doing two calls every time
+  if (not ((clockid = CLOCK_MONOTONIC) or (clockid = CLOCK_MONOTONIC_COARSE) or (clockid = CLOCK_BOOTTIME) or (clockid = CLOCK_UPTIME))) and (not gettime64_nosupport_cached) then begin
+    result := do_syscall(clock_gettime64,clockid,tsysparam(tp));
 
-{$ifndef monotimefloat_implemented} {fallback}
-  
-  function monotimefloat:extended;
-  begin
-    result := unixtimefloat;
+    if ((clockid = CLOCK_REALTIME) or (clockid = CLOCK_REALTIME_COARSE)) and (result <> 0) then gettime64_nosupport_cached := true;
+
+    if (result = 0) then exit;
+  end;
+  {$endif}
+
+  {$ifdef have_clock_gettime}
+  result := clock_gettime(clockid, @ts);
+  if (result <> 0) then begin
+    //fallback
+    if (clockid = CLOCK_REALTIME_COARSE) then begin
+      coarse_nosupport_cached := true;
+      result := clock_gettime(CLOCK_REALTIME, @ts);
+    end else
+    if (clockid = CLOCK_MONOTONIC_COARSE) then begin
+      coarse_nosupport_cached := true;
+      result := clock_gettime(CLOCK_MONOTONIC, @ts);
+    end;
   end;
+  if (result = 0) then begin
+    tp.tv_sec := ts.tv_sec;
+    tp.tv_nsec := ts.tv_nsec;
 
-{$endif} {monotimefloat fallback}
+    {$ifndef cpu64}
+    if (tp.tv_sec < -1) then inc(tp.tv_sec, $100000000);
+    {$endif}
+
+    exit;
+  end;
+  {$endif} //have_clock_gettime
+
+  result := gettimeofday(tv);
+  if (result = 0) then begin
+    tp.tv_sec := tv.tv_sec;
+    tp.tv_nsec := tv.tv_usec * 1000;
+
+    {$ifndef cpu64}
+    if (tp.tv_sec < -1) then inc(tp.tv_sec, $100000000);
+    {$endif}
+  end;
+end;
+
+
+function unixtimefloat:float;
+var
+  ts:tbtimespec;
+begin
+  btime_gettime(CLOCK_REALTIME, @ts);
+  //doing the below as a division causes a bug in fpc 3.2.0 x64, where the result becomes single precision
+  result := ts.tv_sec + (ts.tv_nsec * 0.000000001);
+end;
+
+
+function monotimefloat:float;
+var
+  ts:tbtimespec;
+begin
+  btime_gettime(CLOCK_MONOTONIC, @ts);
+  result := ts.tv_sec + (ts.tv_nsec * 0.000000001);
+end;
+
+
+function unixtimefloat_coarse:float;
+var
+  ts:tbtimespec;
+begin
+  btime_gettime(CLOCK_REALTIME_COARSE, @ts);
+  result := ts.tv_sec + (ts.tv_nsec * 0.000000001);
+end;
+
+
+function monotimefloat_coarse:float;
+var
+  ts:tbtimespec;
+begin
+  btime_gettime(CLOCK_MONOTONIC_COARSE, @ts);
+  result := ts.tv_sec + (ts.tv_nsec * 0.000000001);
+end;
+
+
+function boottimefloat:float;
+var
+  ts:tbtimespec;
+begin
+  btime_gettime(CLOCK_BOOTTIME, @ts);
+  result := ts.tv_sec + (ts.tv_nsec * 0.000000001);
+end;
+
+
+function uptimefloat:float;
+var
+  ts:tbtimespec;
+begin
+  btime_gettime(CLOCK_UPTIME, @ts);
+  result := ts.tv_sec + (ts.tv_nsec * 0.000000001);
+end;
 
 
 function unixtimeint:tunixtimeint;
 var
-  tv:ttimeval;
-  sec:tunixtimeint;
+  ts:tbtimespec;
 begin
-  gettimeofday(tv);
-  sec := tv.tv_sec;
-  {$ifndef cpu64}
-  if (sec < -1) then inc(sec,$100000000); //tv_sec is 32 bits. allow -1 for invalid result
-  {$endif}
-  result := sec;
+  btime_gettime(CLOCK_REALTIME,@ts);
+  result := ts.tv_sec;
 end;
 
 {------------------------------ end of *nix/freepascal section}
 
-{$else} {windows}
+{$endif}  //unix
+
+{$ifdef mswindows}
 {------------------------------ windows/delphi code to read time}
 
 
@@ -277,18 +478,39 @@ begin
   gettimezone;
 end;
 
-{simulate gettimeofday on windows so one can always use gettimeofday if preferred}
 
-procedure gettimeofday(var tv:ttimeval);
 var
-  e:extended;
+  GetTickCount64:function:int64; stdcall;
+  gettickcount64_inited:boolean;
+
+procedure init_gettickcount64;
+var
+  dllhandle:thandle;
 begin
-  e := unixtimefloat;
-  tv.tv_sec := round(int(e));
-  tv.tv_usec := trunc(frac(e)*1000000);
-  {just in case}
-  if (tv.tv_usec < 0) then tv.tv_usec := 0;
-  if (tv.tv_usec > 999999) then tv.tv_usec := 999999;
+  gettickcount64_inited := true;
+  dllhandle := loadlibrary('kernel32.dll');
+  if (dllhandle <> 0) then begin
+    GetTickCount64 := getprocaddress(dllhandle,'GetTickCount64');
+  end;
+end;
+
+
+
+function mmtimeint64:int64;
+var
+  i:int64;
+begin
+  if not gettickcount64_inited then init_gettickcount64;
+  if assigned(GetTickCount64) then begin
+    result := GetTickCount64;
+  end else begin
+    i := gettickcount;
+    if i < mmtime_last then begin
+      mmtime_wrapadd := mmtime_wrapadd + $100000000;
+    end;
+    mmtime_last := i;
+    result := mmtime_wrapadd + i;
+  end;
 end;
 
 
@@ -298,23 +520,12 @@ resolution: 9x: ~55 ms NT: 1/64th of a second
 guarantees: continuous without any jumps
 frequency base: same as system clock.
 epoch: system boot
-note: if called more than once per 49.7 days, 32 bits wrapping is compensated for and it keeps going on.
-note: i handle the timestamp as signed integer, but with the wrap compensation that works as well, and is faster
 }
-
 function mmtimefloat:float;
-const
-  wrapduration=highdwordconst * 0.001;
 var
-  i:integer;
   temp:float;
 begin
-  i := gettickcount; {timegettime}
-  if i < mmtime_last then begin
-    mmtime_wrapadd := mmtime_wrapadd + wrapduration;
-  end;
-  mmtime_last := i;
-  result := mmtime_wrapadd + i * 0.001;
+  result := mmtimeint64 * 0.001;
 
   if (ticks_freq <> 0) and ticks_freq_known then begin
     {the value we get is rounded to 1 ms, but the ticks are not a multiple of 1 ms
@@ -329,14 +540,34 @@ begin
   end;
 end;
 
+var
+  win_version_known:boolean;
+  win_isnt:boolean;
+  win_ver_major:integer;
+  win_ver_minor:integer;
+
+procedure init_win_version;
+var
+  o:tosversioninfo;
+begin
+  if not win_version_known then begin
+    win_version_known := true;
+    fillchar(o,sizeof(o),0);
+    o.dwOSVersionInfoSize := sizeof(o);
+    getversionex(o);
+    win_isnt := o.dwPlatformId = VER_PLATFORM_WIN32_NT;
+    win_ver_major := o.dwMajorVersion;
+    win_ver_minor := o.dwMinorVersion;
+  end;
+end;
+
 procedure measure_ticks_freq;
 var
   f,g:float;
-  o:tosversioninfo;
-  isnt:boolean;
-{  is9x:boolean;}
+
   adjust1,adjust2:cardinal;
   adjustbool:longbool;
+  win8_or_later:boolean;
 begin
   if (performancecountfreq = 0) then qpctimefloat;
   ticks_freq_known := false;
@@ -345,22 +576,26 @@ begin
   repeat g := mmtimefloat until g > f;
   unsettc;
   f := g - f;
-  fillchar(o,sizeof(o),0);
-  o.dwOSVersionInfoSize := sizeof(o);
-  getversionex(o);
-  isnt := o.dwPlatformId = VER_PLATFORM_WIN32_NT;
-{  is9x := o.dwPlatformId = VER_PLATFORM_WIN32_WINDOWS;}
+
+  init_win_version;
 
   ticks_freq2 := f;
   mmtime_synchedqpc := false;
 
-  if (isnt and (o.dwMajorVersion >= 5)) then begin
+  if (win_isnt and (win_ver_major >= 5)) then begin
     {windows 2000 and later: query tick rate from OS in 100 ns units
     typical rates: XP: 156250 or 100144, windows 7: 156001}
     if GetSystemTimeAdjustment(adjust1,adjust2,adjustbool) then begin
       ticks_freq := adjust1 / 10000000.0;
       ticks_freq_known := true;
       mmtime_synchedqpc := false;
+
+      //windows 8/10/11, 10 MHz time source is invariant TSC. add 64 Hz check for safety.
+      //with manifest, windows 10/11 major.minor will be 10.0 
+      win8_or_later := ((win_ver_major = 6) and (win_ver_minor >= 2)) or (win_ver_major = 10);
+      if (win8_or_later and (performancecountfreq = 10000000) and (adjust1 = 156250)) then begin
+        mmtime_synchedqpc := true;
+      end;
     end;
   end;
 
@@ -382,26 +617,16 @@ guarantees: can have forward jumps depending on hardware. can have forward and b
 frequency base: on NT, not the system clock, drifts compared to it.
 epoch: system boot
 }
-function qpctimefloat:extended;
+function qpctimefloat:float;
 var
-  p:packed record
-    lowpart:longint;
-    highpart:longint
-  end;
-  p2:tlargeinteger absolute p;
-  e:extended;
+  i64:int64;
 begin
   if performancecountfreq = 0 then begin
-    QueryPerformancefrequency(p2);
-    e := p.lowpart;
-    if e < 0 then e := e + highdwordconst;
-    performancecountfreq := ((p.highpart*highdwordconst)+e);
+    QueryPerformancefrequency(performancecountfreq);
+    performancecountstep := 1.0 / performancecountfreq;
   end;
-  queryperformancecounter(p2);
-  e := p.lowpart;
-  if e < 0 then e := e + highdwordconst;
-
-  result := ((p.highpart*highdwordconst)+e)/performancecountfreq;
+  queryperformancecounter(i64);
+  result := i64 * performancecountstep;
 end;
 
 {
@@ -412,7 +637,8 @@ frequency base: same as system clock.
 epoch: system boot
 }
 
-function mmqpctimefloat:float;
+//function mmqpctimefloat:float;
+function monotimefloat:float;
 const
   maxretries=5;
   margin=0.002;
@@ -504,63 +730,47 @@ begin
   mmtime_lastresult := result;
 end;
 
-{ free pascals tsystemtime is incompatible with windows api calls
- so we declare it ourselves - plugwash
-}
-{$ifdef fpc}
-type
-  TSystemTime = record
-     wYear: Word;
-     wMonth: Word;
-     wDayOfWeek: Word;
-     wDay: Word;
-     wHour: Word;
-     wMinute: Word;
-     wSecond: Word;
-     wMilliseconds: Word;
-  end;
- {$endif}
-function Date_utc: extended;
-var
-  SystemTime: TSystemTime;
+
+function boottimefloat:float;
 begin
-  {$ifdef fpc}
-    GetsystemTime(@SystemTime);
-  {$else}
-    GetsystemTime(SystemTime);
-  {$endif}
-  with SystemTime do Result := EncodeDate(wYear, wMonth, wDay);
+  result := monotimefloat;
 end;
 
-function Time_utc: extended;
 var
-  SystemTime: TSystemTime;
-begin
-  {$ifdef fpc}
-    GetsystemTime(@SystemTime);
-  {$else}
-    GetsystemTime(SystemTime);
-  {$endif}
-  with SystemTime do
-    Result := EncodeTime(wHour, wMinute, wSecond, wMilliSeconds);
-end;
+  QueryUnbiasedInterruptTime:function(var i:int64):longbool; stdcall;
+  unbiasedinterrupttime_inited:boolean;
+
 
-function Now_utc: extended;
+procedure initunbiasedinterrupttime;
+var
+  dllhandle:thandle;
 begin
-  Result := round(Date_utc) + Time_utc;
+  unbiasedinterrupttime_inited := true;
+  dllhandle := loadlibrary('kernel32.dll');
+  if (dllhandle <> 0) then begin
+    QueryUnbiasedInterruptTime := getprocaddress(dllhandle,'QueryUnbiasedInterruptTime');
+  end;
 end;
 
-function unixtimefloat_systemtime:float;
+function unbiasedtime_100ns:int64;
 begin
-  {result := oletounixfloat(now_utc);}
-
-  {this method gives exactly the same result with extended precision, but is less sensitive to float rounding in theory}
-  result := oletounixfloat(int(date_utc+0.5))+time_utc*86400;
+  result := -1;
+  if not unbiasedinterrupttime_inited then initunbiasedinterrupttime;
+  if assigned(@QueryUnbiasedInterruptTime) then begin
+    QueryUnbiasedInterruptTime(result);
+  end;
 end;
 
-function monotimefloat:extended;
+function uptimefloat:float;
+var
+  i:int64;
 begin
-  result := mmqpctimefloat;
+  i := unbiasedtime_100ns;
+  if (i > 0) then begin
+    result := i * 0.0000001;
+    exit;
+  end;
+  result := qpctimefloat;
 end;
 
 
@@ -582,16 +792,167 @@ begin
 end;
 
 
-function unixtimefloat_win8:float;
+function win8time_as_unix_100ns:int64;
+var
+  ft:tfiletime;
+  i:int64 absolute ft;
+begin
+  result := -1;
+  if not win8inited then initwin8;
+  if assigned(@GetSystemTimePreciseAsFileTime) then begin
+    GetSystemTimePreciseAsFileTime(ft);
+    //change from windows 1601-01-01 to unix 1970-01-01.
+    dec(i, 116444736000000000);
+    result := i;
+  end;
+end;
+
+
+function unixtimefloat_systemtime:float;
 var
   ft:tfiletime;
   i:int64 absolute ft;
 begin
-  GetSystemTimePreciseAsFileTime(ft);
-  {change from windows 1601-01-01 to unix 1970-01-01.
-  use integer math for this, to preserve precision}
+  //result := oletounixfloat(now_utc);
+
+  //this method gives exactly the same result with extended precision, but is less sensitive to float rounding in theory}
+  //result := oletounixfloat(int(date_utc+0.5))+time_utc*86400;
+
+  //new method that is much faster (22 vs 190 ns)
+  GetSystemTimeAsFileTime(ft);
   dec(i, 116444736000000000);
-  result := (i / 10000000);
+  result := i * 0.0000001;
+end;
+
+
+function unixtimefloat_coarse:float;
+begin
+  //don't do the coarse method if worse than about 16 ms. on win9x it may be only a 55 ms resolution
+  //but i have also seen it is less (like 1 ms)
+  //don't call measure_ticks_freq on NT because it is expensive and unnecessary
+  init_win_version;
+  if not win_isnt then begin
+    if not ticks_freq_known then measure_ticks_freq;
+  end;
+  if win_isnt or (ticks_freq < 0.017) then begin
+    result := unixtimefloat_systemtime;
+    exit;
+  end;
+
+  result := unixtimefloat;
+end;
+
+function monotimefloat_coarse:float;
+begin
+  init_win_version;
+  if not win_isnt then begin
+    if not ticks_freq_known then measure_ticks_freq;
+  end;
+  if win_isnt or (ticks_freq < 0.017) then begin
+    result := mmtimeint64 * 0.001;
+    exit;
+  end;
+  result := monotimefloat;
+end;
+
+
+//simulate gettimeofday on windows so one can always use gettimeofday if preferred
+function gettimeofday(var tv:ttimeval):integer;
+var
+  e:float;
+  i:int64;
+begin
+  result := -1;
+
+  if not btimenowin8 then begin
+    i := win8time_as_unix_100ns;
+    if (i > 0) then begin
+      tv.tv_sec := i div 10000000;
+      tv.tv_usec := (i mod 10000000) div 10;
+      result := 0;
+      exit;
+    end;
+  end;
+
+  e := unixtimefloat;
+  if (e > 0) then result := 0;
+  tv.tv_sec := trunc(e);
+  tv.tv_usec := trunc(frac(e)*1000000);
+end;
+
+
+function btime_gettime(clockid:integer;tp:pbtimespec):integer;
+var
+  f:float;
+  i:int64;
+
+{$ifdef cpu386}{$ifdef has_extended}{$define itotp_float}{$endif}{$endif}
+procedure i100ns_to_tp_and_success;
+{$ifdef itotp_float}
+var
+  f:float;
+{$endif}
+begin
+  //in 32 bits delphi, float is 10 times faster than int64 here (30 vs 300 ns for the conversion)
+  //and with extended available, there is no loss of precision
+
+  {$ifdef itotp_float}
+  f := i / 10000000.0;
+  tp.tv_sec := trunc(f);
+  tp.tv_nsec := round(frac(f) * 1000000000.0);
+  {$else}
+  tp.tv_sec := i div 10000000;
+  tp.tv_nsec := (i mod 10000000) * 100;
+  {$endif}
+
+  result := 0; //success
+end;
+
+procedure f_to_tp_and_success;
+begin
+  tp.tv_sec := trunc(f);
+  tp.tv_nsec := round(frac(f) * 1000000000.0);
+  result := 0; //success
+end;
+
+begin
+  result := -1; //error
+
+  case clockid of
+    CLOCK_REALTIME: begin
+      //implement this case directly for full precision even without extended floats
+      if not btimenowin8 then begin
+        i := win8time_as_unix_100ns;
+        if (i > 0) then begin
+          i100ns_to_tp_and_success;
+          exit;
+        end;
+      end;
+      f := unixtimefloat;
+      f_to_tp_and_success;
+    end;
+    CLOCK_MONOTONIC: begin
+      f := monotimefloat;
+      f_to_tp_and_success;
+    end;
+    CLOCK_REALTIME_COARSE: begin
+      f := unixtimefloat_coarse;
+      f_to_tp_and_success;
+    end;
+    CLOCK_MONOTONIC_COARSE: begin
+      f := monotimefloat_coarse;
+      f_to_tp_and_success;
+    end;
+    CLOCK_UPTIME: begin
+      i := unbiasedtime_100ns;
+      if (i > 0) then begin
+        i100ns_to_tp_and_success;
+        exit;
+      end;
+      f := qpctimefloat;
+      f_to_tp_and_success;
+    end;
+  end;
 end;
 
 
@@ -603,17 +964,13 @@ var
   f,g,h:float;
 begin
   if not btimenowin8 then begin
-    if not win8inited then initwin8;
-    if assigned(@GetSystemTimePreciseAsFileTime) then begin
-      result := unixtimefloat_win8;
-      exit;
-    end;  
+    result := win8time_as_unix_100ns * 0.0000001;
+    if (result > 0) then exit;
   end;
 
   result := monotimefloat+timefloatbias;
   f := result-unixtimefloat_systemtime;
   if ((f > ticks_freq2+margin) or (f < -margin)) or (timefloatbias = 0) then begin
-//    writeln('unixtimefloat init');
     f := unixtimefloat_systemtime;
     settc;
     repeat g := unixtimefloat_systemtime; h := monotimefloat until g > f;
@@ -622,8 +979,8 @@ begin
     result := unixtimefloat;
   end;
 
-  {for small changes backwards, guarantee no steps backwards}
-  if (result <= lastunixtimefloat) and (result > lastunixtimefloat-1.5) then result := lastunixtimefloat + 0.0000001;
+  //for small changes backwards, guarantee no steps backwards
+  if (result <= lastunixtimefloat) and (result > lastunixtimefloat-1.5) then result := lastunixtimefloat;
   lastunixtimefloat := result;
 end;
 
@@ -632,7 +989,7 @@ begin
   result := trunc(unixtimefloat);
 end;
 
-{$endif}
+{$endif}  //mswindows
 {-----------------------------------------------end of platform specific}
 
 function wintimefloat:float;
@@ -665,7 +1022,7 @@ procedure timehandler;
 begin
   if unixtime = 0 then init;
   unixtime := unixtimeint;
-  irctime := irctimeint;
+  irctime := unixtime+settimebias;
   if unixtime and 63 = 0 then begin
     {update everything, apply timezone changes, clock changes, etc}
     gettimezone;
@@ -685,18 +1042,28 @@ var
 function tzgetfilename:ansistring;
 var
   t:textfile;
-
+  a:integer;
   s,tz,tzdir:ansistring;
+  ispath:boolean;
 begin
   result := '';
   filemode := 0;
-  {$ifdef unix}
+
   tz := getenv('TZ');
 
-  if (copy(tz,1,1) = ':') then begin
-    tz := copy(tz,2,99999);
+  if (tz <> '') then begin
+    ispath := false;
+    if (copy(tz,1,1) = ':') then begin
+      ispath := true;
+      tz := copy(tz,2,99999);
+    end;
 
     if (copy(tz,1,1) <> '/') then begin
+      a := pos(',',tz);
+      if (a > 1) and not ispath then begin
+        tz := copy(tz,1,a-1);
+      end;
+
       tzdir := getenv('TZDIR');
       if (tzdir = '') then begin
         tzdir := '/usr/share/zoneinfo/';
@@ -715,8 +1082,7 @@ begin
     end;
 
   end;
-  {$endif}
-  
+
   assignfile(t,'/etc/localtime');
   {$i-}reset(t);{$i+}
   if (ioresult = 0) then begin
@@ -724,19 +1090,6 @@ begin
     result := '/etc/localtime';
     exit;
   end;
-
-  assignfile(t,'/etc/timezone');
-
-  s := '';
-  {$i-}reset(t);{$i+}
-  if (ioresult = 0) then begin
-    readln(t,s);
-    closefile(t);
-    if (s <> '') then begin
-      result := '/usr/share/zoneinfo/'+s;
-      exit;
-    end;
-  end;
 end;
 
 type
@@ -891,17 +1244,9 @@ begin
  end;
 end;
 
-function tzgetoffset:integer;
-begin
-  tzgetoffsetforts(unixtimeint);
-end;
-
-
-{$endif}
-
+{$endif}  //unix
 
-procedure gettimezone;
-var
+function tzgetoffset:integer;
   {$ifdef UNIX}
     {$ifndef ver1_9_4}
       {$ifndef ver1_0}
@@ -909,25 +1254,46 @@ var
       {$endif}
     {$endif}
     {$ifndef above194}
+var
       hh,mm,ss:word;
     {$endif}
+  {$else}
+var
+  TimeZoneInfo: TIME_ZONE_INFORMATION;
+  tztype:cardinal;
+  min:integer;
   {$endif}
-  l:integer;
+
 begin
   {$ifdef UNIX}
     {$ifdef above194}
-      timezone := tzgetoffset;
+      result := tzgetoffsetforts(unixtimeint);
       //freepascal tzseconds is not 2038 safe
     {$else}
       gettime(hh,mm,ss);
-      timezone := (longint(hh) * 3600 + mm * 60 + ss) - (unixtimeint mod 86400);
+      result := (integer(hh) * 3600 + mm * 60 + ss) - (unixtimeint mod 86400);
     {$endif}
   {$else}
-  timezone := round((now-now_utc)*86400);
+    tztype := GetTimeZoneInformation(TimeZoneInfo);
+    min := TimeZoneInfo.Bias;
+    case tztype of
+      //TIME_ZONE_ID_UNKNOWN: don't add DST
+      TIME_ZONE_ID_STANDARD: inc(min, TimeZoneInfo.StandardBias);
+      TIME_ZONE_ID_DAYLIGHT: inc(min, TimeZoneInfo.DaylightBias);
+    end;
+    result := min * -60;
   {$endif}
 
-  while timezone > 50400 do dec(timezone,86400);
-  while timezone < -50400 do inc(timezone,86400);
+  while result > (14 * 3600) do dec(result,86400);
+  while result < -(14 * 3600) do inc(result,86400);
+end;
+
+
+procedure gettimezone;
+var
+  l:integer;
+begin
+  timezone := tzgetoffset;
 
   if timezone >= 0 then timezonestr := '+' else timezonestr := '-';
   l := abs(timezone) div 60;
diff --git a/ltimevalstuff.pas b/ltimevalstuff.pas
index 7a10c7a..da8bb94 100644
--- a/ltimevalstuff.pas
+++ b/ltimevalstuff.pas
@@ -10,11 +10,19 @@
 unit ltimevalstuff;
 interface
 
+
+{$ifdef CONDITIONALEXPRESSIONS}{$define support_int64}{$endif}    //delphi 6 or later
+{$ifdef fpc}{$define support_int64}{$endif}
+
 {$ifdef mswindows}
   type
     ttimeval = record
-      tv_sec : longint; 
-      tv_usec : longint; 
+      {$IFDEF support_int64}
+      tv_sec : int64;
+      {$ELSE}
+      tv_sec : longint;
+      {$ENDIF}
+      tv_usec : longint;
     end;
 {$else}
   {$ifdef ver1_0}
diff --git a/unixstuff.inc b/unixstuff.inc
index 1a9a97b..ae615ff 100644
--- a/unixstuff.inc
+++ b/unixstuff.inc
@@ -125,9 +125,9 @@
       end;
       {$define need_v6constants}
     {$endif}
-    procedure gettimeofday(var tv:ttimeval);inline;
+    function gettimeofday(var tv:ttimeval):integer; inline;
     begin
-      fpgettimeofday(@tv,nil);    
+      result := fpgettimeofday(@tv,nil);
     end;
     function gettimeofdaysec : longint;
     var
-- 
2.30.2