1------------------------------------------------------------------------------ 2-- -- 3-- GNAT RUN-TIME COMPONENTS -- 4-- -- 5-- A D A . C A L E N D A R -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2012, Free Software Foundation, Inc. -- 10-- -- 11-- This specification is derived from the Ada Reference Manual for use with -- 12-- GNAT. The copyright notice above, and the license provisions that follow -- 13-- apply solely to the contents of the part following the private keyword. -- 14-- -- 15-- GNAT is free software; you can redistribute it and/or modify it under -- 16-- terms of the GNU General Public License as published by the Free Soft- -- 17-- ware Foundation; either version 3, or (at your option) any later ver- -- 18-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 19-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 20-- or FITNESS FOR A PARTICULAR PURPOSE. -- 21-- -- 22-- As a special exception under Section 7 of GPL version 3, you are granted -- 23-- additional permissions described in the GCC Runtime Library Exception, -- 24-- version 3.1, as published by the Free Software Foundation. -- 25-- -- 26-- You should have received a copy of the GNU General Public License and -- 27-- a copy of the GCC Runtime Library Exception along with this program; -- 28-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 29-- <http://www.gnu.org/licenses/>. -- 30-- -- 31-- GNAT was originally developed by the GNAT team at New York University. -- 32-- Extensive contributions were provided by Ada Core Technologies Inc. -- 33-- -- 34------------------------------------------------------------------------------ 35 36-- This is the OpenVMS version 37 38with System.OS_Primitives; 39 40package Ada.Calendar is 41 42 type Time is private; 43 44 -- Declarations representing limits of allowed local time values. Note that 45 -- these do NOT constrain the possible stored values of time which may well 46 -- permit a larger range of times (this is explicitly allowed in Ada 95). 47 48 subtype Year_Number is Integer range 1901 .. 2399; 49 subtype Month_Number is Integer range 1 .. 12; 50 subtype Day_Number is Integer range 1 .. 31; 51 52 subtype Day_Duration is Duration range 0.0 .. 86_400.0; 53 -- Note that a value of 86_400.0 is the start of the next day 54 55 function Clock return Time; 56 -- The returned time value is the number of nanoseconds since the start 57 -- of Ada time (1901-01-01 00:00:00.0 UTC). If leap seconds are enabled, 58 -- the result will contain all elapsed leap seconds since the start of 59 -- Ada time until now. 60 61 function Year (Date : Time) return Year_Number; 62 function Month (Date : Time) return Month_Number; 63 function Day (Date : Time) return Day_Number; 64 function Seconds (Date : Time) return Day_Duration; 65 66 procedure Split 67 (Date : Time; 68 Year : out Year_Number; 69 Month : out Month_Number; 70 Day : out Day_Number; 71 Seconds : out Day_Duration); 72 -- Break down a time value into its date components set in the current 73 -- time zone. If Split is called on a time value created using Ada 2005 74 -- Time_Of in some arbitrary time zone, the input value will always be 75 -- interpreted as relative to the local time zone. 76 77 function Time_Of 78 (Year : Year_Number; 79 Month : Month_Number; 80 Day : Day_Number; 81 Seconds : Day_Duration := 0.0) return Time; 82 -- GNAT Note: Normally when procedure Split is called on a Time value 83 -- result of a call to function Time_Of, the out parameters of procedure 84 -- Split are identical to the in parameters of function Time_Of. However, 85 -- when a non-existent time of day is specified, the values for Seconds 86 -- may or may not be different. This may happen when Daylight Saving Time 87 -- (DST) is in effect, on the day when switching to DST, if Seconds 88 -- specifies a time of day in the hour that does not exist. For example, 89 -- in New York: 90 -- 91 -- Time_Of (Year => 1998, Month => 4, Day => 5, Seconds => 10740.0) 92 -- 93 -- will return a Time value T. If Split is called on T, the resulting 94 -- Seconds may be 14340.0 (3:59:00) instead of 10740.0 (2:59:00 being 95 -- a time that not exist). 96 97 function "+" (Left : Time; Right : Duration) return Time; 98 function "+" (Left : Duration; Right : Time) return Time; 99 function "-" (Left : Time; Right : Duration) return Time; 100 function "-" (Left : Time; Right : Time) return Duration; 101 -- The first three functions will raise Time_Error if the resulting time 102 -- value is less than the start of Ada time in UTC or greater than the 103 -- end of Ada time in UTC. The last function will raise Time_Error if the 104 -- resulting difference cannot fit into a duration value. 105 106 function "<" (Left, Right : Time) return Boolean; 107 function "<=" (Left, Right : Time) return Boolean; 108 function ">" (Left, Right : Time) return Boolean; 109 function ">=" (Left, Right : Time) return Boolean; 110 111 Time_Error : exception; 112 113private 114 pragma Inline (Clock); 115 116 pragma Inline (Year); 117 pragma Inline (Month); 118 pragma Inline (Day); 119 120 pragma Inline ("+"); 121 pragma Inline ("-"); 122 123 pragma Inline ("<"); 124 pragma Inline ("<="); 125 pragma Inline (">"); 126 pragma Inline (">="); 127 128 -- Although the units are 100 nanoseconds, for the purpose of better 129 -- readability, this unit will be called "mili". 130 131 Mili : constant := 10_000_000; 132 Mili_F : constant := 10_000_000.0; 133 Milis_In_Day : constant := 864_000_000_000; 134 Secs_In_Day : constant := 86_400; 135 136 -- Time is represented as the number of 100-nanosecond (ns) units from the 137 -- system base date and time 1858-11-17 0.0 (the Smithsonian base date and 138 -- time for the astronomic calendar). 139 140 -- The time value stored is typically a UTC value, as provided in standard 141 -- Unix environments. If this is the case then Split and Time_Of perform 142 -- required conversions to and from local times. 143 144 -- Notwithstanding this definition, Time is not quite the same as OS_Time. 145 -- Relative Time is positive, whereas relative OS_Time is negative, 146 -- but this declaration makes for easier conversion. 147 148 type Time is new System.OS_Primitives.OS_Time; 149 150 Days_In_Month : constant array (Month_Number) of Day_Number := 151 (31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31); 152 -- Days in month for non-leap year, leap year case is adjusted in code 153 154 Invalid_Time_Zone_Offset : Long_Integer; 155 pragma Import (C, Invalid_Time_Zone_Offset, "__gnat_invalid_tzoff"); 156 157 function Is_Leap (Year : Year_Number) return Boolean; 158 -- Determine whether a given year is leap 159 160 ---------------------------------------------------------- 161 -- Target-Independent Interface to Children of Calendar -- 162 ---------------------------------------------------------- 163 164 -- The following packages provide a target-independent interface to the 165 -- children of Calendar - Arithmetic, Conversions, Delays, Formatting and 166 -- Time_Zones. 167 168 -- NOTE: Delays does not need a target independent interface because 169 -- VMS already has a target specific file for that package. 170 171 --------------------------- 172 -- Arithmetic_Operations -- 173 --------------------------- 174 175 package Arithmetic_Operations is 176 177 function Add (Date : Time; Days : Long_Integer) return Time; 178 -- Add a certain number of days to a time value 179 180 procedure Difference 181 (Left : Time; 182 Right : Time; 183 Days : out Long_Integer; 184 Seconds : out Duration; 185 Leap_Seconds : out Integer); 186 -- Calculate the difference between two time values in terms of days, 187 -- seconds and leap seconds elapsed. The leap seconds are not included 188 -- in the seconds returned. If Left is greater than Right, the returned 189 -- values are positive, negative otherwise. 190 191 function Subtract (Date : Time; Days : Long_Integer) return Time; 192 -- Subtract a certain number of days from a time value 193 194 end Arithmetic_Operations; 195 196 --------------------------- 197 -- Conversion_Operations -- 198 --------------------------- 199 200 package Conversion_Operations is 201 202 function To_Ada_Time (Unix_Time : Long_Integer) return Time; 203 -- Unix to Ada Epoch conversion 204 205 function To_Ada_Time 206 (tm_year : Integer; 207 tm_mon : Integer; 208 tm_day : Integer; 209 tm_hour : Integer; 210 tm_min : Integer; 211 tm_sec : Integer; 212 tm_isdst : Integer) return Time; 213 -- Struct tm to Ada Epoch conversion 214 215 function To_Duration 216 (tv_sec : Long_Integer; 217 tv_nsec : Long_Integer) return Duration; 218 -- Struct timespec to Duration conversion 219 220 procedure To_Struct_Timespec 221 (D : Duration; 222 tv_sec : out Long_Integer; 223 tv_nsec : out Long_Integer); 224 -- Duration to struct timespec conversion 225 226 procedure To_Struct_Tm 227 (T : Time; 228 tm_year : out Integer; 229 tm_mon : out Integer; 230 tm_day : out Integer; 231 tm_hour : out Integer; 232 tm_min : out Integer; 233 tm_sec : out Integer); 234 -- Time to struct tm conversion 235 236 function To_Unix_Time (Ada_Time : Time) return Long_Integer; 237 -- Ada to Unix Epoch conversion 238 239 end Conversion_Operations; 240 241 --------------------------- 242 -- Formatting_Operations -- 243 --------------------------- 244 245 package Formatting_Operations is 246 247 function Day_Of_Week (Date : Time) return Integer; 248 -- Determine which day of week Date falls on. The returned values are 249 -- within the range of 0 .. 6 (Monday .. Sunday). 250 251 procedure Split 252 (Date : Time; 253 Year : out Year_Number; 254 Month : out Month_Number; 255 Day : out Day_Number; 256 Day_Secs : out Day_Duration; 257 Hour : out Integer; 258 Minute : out Integer; 259 Second : out Integer; 260 Sub_Sec : out Duration; 261 Leap_Sec : out Boolean; 262 Use_TZ : Boolean; 263 Is_Historic : Boolean; 264 Time_Zone : Long_Integer); 265 pragma Export (Ada, Split, "__gnat_split"); 266 -- Split a time value into its components. If flag Is_Historic is set, 267 -- this routine would try to use to the best of the OS's abilities the 268 -- time zone offset that was or will be in effect on Date. Set Use_TZ 269 -- to use the local time zone (the value in Time_Zone is ignored) when 270 -- splitting a time value. 271 272 function Time_Of 273 (Year : Year_Number; 274 Month : Month_Number; 275 Day : Day_Number; 276 Day_Secs : Day_Duration; 277 Hour : Integer; 278 Minute : Integer; 279 Second : Integer; 280 Sub_Sec : Duration; 281 Leap_Sec : Boolean; 282 Use_Day_Secs : Boolean; 283 Use_TZ : Boolean; 284 Is_Historic : Boolean; 285 Time_Zone : Long_Integer) return Time; 286 pragma Export (Ada, Time_Of, "__gnat_time_of"); 287 -- Given all the components of a date, return the corresponding time 288 -- value. Set Use_Day_Secs to use the value in Day_Secs, otherwise the 289 -- day duration will be calculated from Hour, Minute, Second and Sub_ 290 -- Sec. If flag Is_Historic is set, this routine would try to use to the 291 -- best of the OS's abilities the time zone offset that was or will be 292 -- in effect on the input date. Set Use_TZ to use the local time zone 293 -- (the value in formal Time_Zone is ignored) when building a time value 294 -- and to verify the validity of a requested leap second. 295 296 end Formatting_Operations; 297 298 --------------------------- 299 -- Time_Zones_Operations -- 300 --------------------------- 301 302 package Time_Zones_Operations is 303 304 function UTC_Time_Offset (Date : Time) return Long_Integer; 305 -- Return (in seconds) the difference between the local time zone and 306 -- UTC time at a specific historic date. 307 308 end Time_Zones_Operations; 309 310end Ada.Calendar; 311