DIRECTORY
HostTime,
Real,
UnixSysCalls,
UnixTypes;

HostTimeUnixImpl: CEDAR PROGRAM
IMPORTS Real, UnixSysCalls
EXPORTS HostTime
~ BEGIN

Time: TYPE = HostTime.Time;
ExtendedGMT: TYPE = HostTime.ExtendedGMT;
ZoneAndDST: TYPE = HostTime.ZoneAndDST;

gmtBaseYear: CARDINAL = 1968; -- really should come from BasicTime, but it's not exported

unixBaseYear: CARDINAL = 1970; -- Unix times start at 00:00Z Jan 1, 1978.

unixCorrection: CARD = (((unixBaseYear-gmtBaseYear)*365+1) * 24*60*60) -- '68 was a leap year -- ;

HostTimeFromExtendedGMT: PUBLIC PROC [egmt: ExtendedGMT] RETURNS [time: Time ¬ [0, 0, 0, 0]] ~ {
time.a ¬ -unixCorrection + LOOPHOLE[egmt.gmt];
time.b ¬ egmt.usecs;
};

ExtendedGMTFromHostTime: PUBLIC PROC [time: Time] RETURNS [egmt: ExtendedGMT] ~ {
egmt.gmt ¬ LOOPHOLE[time.a+unixCorrection];
egmt.usecs ¬ time.b;
};

GetTime: PUBLIC PROC [] RETURNS [time: Time ¬ [0, 0, 0, 0]] ~ TRUSTED {
timeVal: UnixTypes.TimeVal ¬ [0, 0];
[] ¬ UnixSysCalls.GetTimeOfDay[tp: @timeVal, tzp: NIL];
time.a ¬ timeVal.sec;
time.b ¬ timeVal.usec;
};

TimeToMicroseconds: PUBLIC PROC [time: Time] RETURNS [CARD] ~ {
RETURN [CARD[time.b]+LOOPHOLE[time.a, CARD]*1000000];
};

MicrosecondsToTime: PUBLIC PROC [usecs: CARD] RETURNS [time: Time] ~ {
RETURN [[usecs/1000000, usecs MOD 1000000, 0, 0]];
};

TimeToSeconds: PUBLIC PROC [time: Time] RETURNS [REAL] ~ {
RETURN [time.a + time.b*1.0e-6];
};

SecondsToTime: PUBLIC PROC [secs: REAL] RETURNS [Time] ~ {
RETURN [[Real.Floor[secs], Real.Round[1000000*(secs-Real.Floor[secs])], 0, 0]];
};

GetZoneAndDST: PUBLIC PROC [] RETURNS [tp: ZoneAndDST] ~ TRUSTED {
unixTimeZone: UnixTypes.TimeZone;
TRUSTED {[] ¬ UnixSysCalls.GetTimeOfDay[tp: NIL, tzp: @unixTimeZone]};
tp.zone ¬ unixTimeZone.minutesWest;
IF unixTimeZone.dstTime # 0 THEN {
tp.beginDST ¬ 98;
tp.endDST ¬ 305; }
ELSE {
tp.beginDST ¬ 366; -- never use dst
tp.endDST ¬ 1;
};
};


END.
  V  
HostTimeUnixImpl.mesa
Copyright Ó 1988, 1991 by Xerox Corporation.  All rights reserved.
Carl Hauser, November 14, 1988 11:17:56 am PST
Willie-s, August 13, 1991 12:19 pm PDT

Returns the number of seconds.  Beware:  reals have only 24 bits of precision, so the fractional part of the result is not as accurate as calling PulsesToMicroseconds.  However, the result never overflows.
This is thoroughly unsatisfactory, but the SunOS doesn't know these things.  It's built into their conversion code.  These are the right numbers for 1988
Carl Hauser, October 25, 1988 5:34:21 pm PDT
New file

Êå  –(cedarcode) style•NewlineDelimiter
™ code™Kšœ
Ïeœ7™BK™.K™&K™ —šÏk	˜	Kšœ	˜	K˜K˜Kšœ
˜
K˜ —KšÐlnœž˜Kšžœ˜Kšžœ	˜šœž˜K˜ Kšœžœ˜Kšœžœ˜)Kšœžœ˜'K˜ Kšœžœ	Ïc;˜YK˜ Kšœžœ	 *˜IK˜ Kšœžœ3 œ˜bK˜ šÏnœžœžœžœ ˜`Kšœžœ˜.Kšœ˜Kšœ˜K˜ —š¡œžœžœ˜QKšœžœ˜+K˜Kšœ˜K˜ —š¡œžœžœžœ˜GKšœ$˜$Inowšœ2žœ˜7K˜K˜Kšœ˜K˜ —š¡œžœžœžœ˜?Kšžœžœ	žœ	žœ˜5Kšœ˜K˜ —š¡œžœžœžœ˜FKšžœžœ˜2Kšœ˜K˜ —š¡œžœžœžœ˜:K™ÍKšžœ˜ Kšœ˜K˜ —š¡œžœžœžœ˜:KšžœI˜OKšœ˜—K˜ š
¡œžœžœžœžœ˜BKšœ!˜!Kšžœ%žœ˜FKšœ#˜#K™™šžœžœ˜"Kšœ˜Kšœ˜—šžœ˜Kšœ ˜#Kšœ˜K˜—Kšœ˜—K˜ —K˜ Kšžœ˜™,K™—K™ — …—    ^  ™  