| 1 | ;;; srfi-19.scm --- Time/Date Library |
| 2 | |
| 3 | ;; Copyright (C) 2001, 2002, 2003, 2005 Free Software Foundation, Inc. |
| 4 | ;; |
| 5 | ;; This library is free software; you can redistribute it and/or |
| 6 | ;; modify it under the terms of the GNU Lesser General Public |
| 7 | ;; License as published by the Free Software Foundation; either |
| 8 | ;; version 2.1 of the License, or (at your option) any later version. |
| 9 | ;; |
| 10 | ;; This library is distributed in the hope that it will be useful, |
| 11 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | ;; Lesser General Public License for more details. |
| 14 | ;; |
| 15 | ;; You should have received a copy of the GNU Lesser General Public |
| 16 | ;; License along with this library; if not, write to the Free Software |
| 17 | ;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | |
| 19 | ;;; Author: Rob Browning <rlb@cs.utexas.edu> |
| 20 | ;;; Originally from SRFI reference implementation by Will Fitzgerald. |
| 21 | |
| 22 | ;;; Commentary: |
| 23 | |
| 24 | ;; This module is fully documented in the Guile Reference Manual. |
| 25 | |
| 26 | ;;; Code: |
| 27 | |
| 28 | ;; FIXME: I haven't checked a decent amount of this code for potential |
| 29 | ;; performance improvements, but I suspect that there may be some |
| 30 | ;; substantial ones to be realized, esp. in the later "parsing" half |
| 31 | ;; of the file, by rewriting the code with use of more Guile native |
| 32 | ;; functions that do more work in a "chunk". |
| 33 | ;; |
| 34 | ;; FIXME: mkoeppe: Time zones are treated a little simplistic in |
| 35 | ;; SRFI-19; they are only a numeric offset. Thus, printing time zones |
| 36 | ;; (PRIV:LOCALE-PRINT-TIME-ZONE) can't be implemented sensibly. The |
| 37 | ;; functions taking an optional TZ-OFFSET should be extended to take a |
| 38 | ;; symbolic time-zone (like "CET"); this string should be stored in |
| 39 | ;; the DATE structure. |
| 40 | |
| 41 | (define-module (srfi srfi-19) |
| 42 | :use-module (srfi srfi-6) |
| 43 | :use-module (srfi srfi-8) |
| 44 | :use-module (srfi srfi-9)) |
| 45 | |
| 46 | (begin-deprecated |
| 47 | ;; Prevent `export' from re-exporting core bindings. This behaviour |
| 48 | ;; of `export' is deprecated and will disappear in one of the next |
| 49 | ;; releases. |
| 50 | (define current-time #f)) |
| 51 | |
| 52 | (export ;; Constants |
| 53 | time-duration |
| 54 | time-monotonic |
| 55 | time-process |
| 56 | time-tai |
| 57 | time-thread |
| 58 | time-utc |
| 59 | ;; Current time and clock resolution |
| 60 | current-date |
| 61 | current-julian-day |
| 62 | current-modified-julian-day |
| 63 | current-time |
| 64 | time-resolution |
| 65 | ;; Time object and accessors |
| 66 | make-time |
| 67 | time? |
| 68 | time-type |
| 69 | time-nanosecond |
| 70 | time-second |
| 71 | set-time-type! |
| 72 | set-time-nanosecond! |
| 73 | set-time-second! |
| 74 | copy-time |
| 75 | ;; Time comparison procedures |
| 76 | time<=? |
| 77 | time<? |
| 78 | time=? |
| 79 | time>=? |
| 80 | time>? |
| 81 | ;; Time arithmetic procedures |
| 82 | time-difference |
| 83 | time-difference! |
| 84 | add-duration |
| 85 | add-duration! |
| 86 | subtract-duration |
| 87 | subtract-duration! |
| 88 | ;; Date object and accessors |
| 89 | make-date |
| 90 | date? |
| 91 | date-nanosecond |
| 92 | date-second |
| 93 | date-minute |
| 94 | date-hour |
| 95 | date-day |
| 96 | date-month |
| 97 | date-year |
| 98 | date-zone-offset |
| 99 | date-year-day |
| 100 | date-week-day |
| 101 | date-week-number |
| 102 | ;; Time/Date/Julian Day/Modified Julian Day converters |
| 103 | date->julian-day |
| 104 | date->modified-julian-day |
| 105 | date->time-monotonic |
| 106 | date->time-tai |
| 107 | date->time-utc |
| 108 | julian-day->date |
| 109 | julian-day->time-monotonic |
| 110 | julian-day->time-tai |
| 111 | julian-day->time-utc |
| 112 | modified-julian-day->date |
| 113 | modified-julian-day->time-monotonic |
| 114 | modified-julian-day->time-tai |
| 115 | modified-julian-day->time-utc |
| 116 | time-monotonic->date |
| 117 | time-monotonic->time-tai |
| 118 | time-monotonic->time-tai! |
| 119 | time-monotonic->time-utc |
| 120 | time-monotonic->time-utc! |
| 121 | time-tai->date |
| 122 | time-tai->julian-day |
| 123 | time-tai->modified-julian-day |
| 124 | time-tai->time-monotonic |
| 125 | time-tai->time-monotonic! |
| 126 | time-tai->time-utc |
| 127 | time-tai->time-utc! |
| 128 | time-utc->date |
| 129 | time-utc->julian-day |
| 130 | time-utc->modified-julian-day |
| 131 | time-utc->time-monotonic |
| 132 | time-utc->time-monotonic! |
| 133 | time-utc->time-tai |
| 134 | time-utc->time-tai! |
| 135 | ;; Date to string/string to date converters. |
| 136 | date->string |
| 137 | string->date) |
| 138 | |
| 139 | (cond-expand-provide (current-module) '(srfi-19)) |
| 140 | |
| 141 | (define time-tai 'time-tai) |
| 142 | (define time-utc 'time-utc) |
| 143 | (define time-monotonic 'time-monotonic) |
| 144 | (define time-thread 'time-thread) |
| 145 | (define time-process 'time-process) |
| 146 | (define time-duration 'time-duration) |
| 147 | |
| 148 | ;; FIXME: do we want to add gc time? |
| 149 | ;; (define time-gc 'time-gc) |
| 150 | |
| 151 | ;;-- LOCALE dependent constants |
| 152 | |
| 153 | (define priv:locale-number-separator ".") |
| 154 | |
| 155 | (define priv:locale-abbr-weekday-vector |
| 156 | (vector "Sun" "Mon" "Tue" "Wed" "Thu" "Fri" "Sat")) |
| 157 | |
| 158 | (define priv:locale-long-weekday-vector |
| 159 | (vector |
| 160 | "Sunday" "Monday" "Tuesday" "Wednesday" "Thursday" "Friday" "Saturday")) |
| 161 | |
| 162 | ;; note empty string in 0th place. |
| 163 | (define priv:locale-abbr-month-vector |
| 164 | (vector "" |
| 165 | "Jan" |
| 166 | "Feb" |
| 167 | "Mar" |
| 168 | "Apr" |
| 169 | "May" |
| 170 | "Jun" |
| 171 | "Jul" |
| 172 | "Aug" |
| 173 | "Sep" |
| 174 | "Oct" |
| 175 | "Nov" |
| 176 | "Dec")) |
| 177 | |
| 178 | (define priv:locale-long-month-vector |
| 179 | (vector "" |
| 180 | "January" |
| 181 | "February" |
| 182 | "March" |
| 183 | "April" |
| 184 | "May" |
| 185 | "June" |
| 186 | "July" |
| 187 | "August" |
| 188 | "September" |
| 189 | "October" |
| 190 | "November" |
| 191 | "December")) |
| 192 | |
| 193 | (define priv:locale-pm "PM") |
| 194 | (define priv:locale-am "AM") |
| 195 | |
| 196 | ;; See date->string |
| 197 | (define priv:locale-date-time-format "~a ~b ~d ~H:~M:~S~z ~Y") |
| 198 | (define priv:locale-short-date-format "~m/~d/~y") |
| 199 | (define priv:locale-time-format "~H:~M:~S") |
| 200 | (define priv:iso-8601-date-time-format "~Y-~m-~dT~H:~M:~S~z") |
| 201 | |
| 202 | ;;-- Miscellaneous Constants. |
| 203 | ;;-- only the priv:tai-epoch-in-jd might need changing if |
| 204 | ;; a different epoch is used. |
| 205 | |
| 206 | (define priv:nano 1000000000) ; nanoseconds in a second |
| 207 | (define priv:sid 86400) ; seconds in a day |
| 208 | (define priv:sihd 43200) ; seconds in a half day |
| 209 | (define priv:tai-epoch-in-jd 4881175/2) ; julian day number for 'the epoch' |
| 210 | |
| 211 | ;; FIXME: should this be something other than misc-error? |
| 212 | (define (priv:time-error caller type value) |
| 213 | (if value |
| 214 | (throw 'misc-error caller "TIME-ERROR type ~A: ~S" (list type value) #f) |
| 215 | (throw 'misc-error caller "TIME-ERROR type ~A" (list type) #f))) |
| 216 | |
| 217 | ;; A table of leap seconds |
| 218 | ;; See ftp://maia.usno.navy.mil/ser7/tai-utc.dat |
| 219 | ;; and update as necessary. |
| 220 | ;; this procedures reads the file in the abover |
| 221 | ;; format and creates the leap second table |
| 222 | ;; it also calls the almost standard, but not R5 procedures read-line |
| 223 | ;; & open-input-string |
| 224 | ;; ie (set! priv:leap-second-table (priv:read-tai-utc-date "tai-utc.dat")) |
| 225 | |
| 226 | (define (priv:read-tai-utc-data filename) |
| 227 | (define (convert-jd jd) |
| 228 | (* (- (inexact->exact jd) priv:tai-epoch-in-jd) priv:sid)) |
| 229 | (define (convert-sec sec) |
| 230 | (inexact->exact sec)) |
| 231 | (let ((port (open-input-file filename)) |
| 232 | (table '())) |
| 233 | (let loop ((line (read-line port))) |
| 234 | (if (not (eq? line eof)) |
| 235 | (begin |
| 236 | (let* ((data (read (open-input-string |
| 237 | (string-append "(" line ")")))) |
| 238 | (year (car data)) |
| 239 | (jd (cadddr (cdr data))) |
| 240 | (secs (cadddr (cdddr data)))) |
| 241 | (if (>= year 1972) |
| 242 | (set! table (cons |
| 243 | (cons (convert-jd jd) (convert-sec secs)) |
| 244 | table))) |
| 245 | (loop (read-line port)))))) |
| 246 | table)) |
| 247 | |
| 248 | ;; each entry is (tai seconds since epoch . # seconds to subtract for utc) |
| 249 | ;; note they go higher to lower, and end in 1972. |
| 250 | (define priv:leap-second-table |
| 251 | '((1136073600 . 33) |
| 252 | (915148800 . 32) |
| 253 | (867715200 . 31) |
| 254 | (820454400 . 30) |
| 255 | (773020800 . 29) |
| 256 | (741484800 . 28) |
| 257 | (709948800 . 27) |
| 258 | (662688000 . 26) |
| 259 | (631152000 . 25) |
| 260 | (567993600 . 24) |
| 261 | (489024000 . 23) |
| 262 | (425865600 . 22) |
| 263 | (394329600 . 21) |
| 264 | (362793600 . 20) |
| 265 | (315532800 . 19) |
| 266 | (283996800 . 18) |
| 267 | (252460800 . 17) |
| 268 | (220924800 . 16) |
| 269 | (189302400 . 15) |
| 270 | (157766400 . 14) |
| 271 | (126230400 . 13) |
| 272 | (94694400 . 12) |
| 273 | (78796800 . 11) |
| 274 | (63072000 . 10))) |
| 275 | |
| 276 | (define (read-leap-second-table filename) |
| 277 | (set! priv:leap-second-table (priv:read-tai-utc-data filename)) |
| 278 | (values)) |
| 279 | |
| 280 | |
| 281 | (define (priv:leap-second-delta utc-seconds) |
| 282 | (letrec ((lsd (lambda (table) |
| 283 | (cond ((>= utc-seconds (caar table)) |
| 284 | (cdar table)) |
| 285 | (else (lsd (cdr table))))))) |
| 286 | (if (< utc-seconds (* (- 1972 1970) 365 priv:sid)) 0 |
| 287 | (lsd priv:leap-second-table)))) |
| 288 | |
| 289 | |
| 290 | ;;; the TIME structure; creates the accessors, too. |
| 291 | |
| 292 | (define-record-type time |
| 293 | (make-time-unnormalized type nanosecond second) |
| 294 | time? |
| 295 | (type time-type set-time-type!) |
| 296 | (nanosecond time-nanosecond set-time-nanosecond!) |
| 297 | (second time-second set-time-second!)) |
| 298 | |
| 299 | (define (copy-time time) |
| 300 | (make-time (time-type time) (time-nanosecond time) (time-second time))) |
| 301 | |
| 302 | (define (priv:split-real r) |
| 303 | (if (integer? r) |
| 304 | (values (inexact->exact r) 0) |
| 305 | (let ((l (truncate r))) |
| 306 | (values (inexact->exact l) (- r l))))) |
| 307 | |
| 308 | (define (priv:time-normalize! t) |
| 309 | (if (>= (abs (time-nanosecond t)) 1000000000) |
| 310 | (receive (int frac) |
| 311 | (priv:split-real (time-nanosecond t)) |
| 312 | (set-time-second! t (+ (time-second t) |
| 313 | (quotient int 1000000000))) |
| 314 | (set-time-nanosecond! t (+ (remainder int 1000000000) |
| 315 | frac)))) |
| 316 | (if (and (positive? (time-second t)) |
| 317 | (negative? (time-nanosecond t))) |
| 318 | (begin |
| 319 | (set-time-second! t (- (time-second t) 1)) |
| 320 | (set-time-nanosecond! t (+ 1000000000 (time-nanosecond t)))) |
| 321 | (if (and (negative? (time-second t)) |
| 322 | (positive? (time-nanosecond t))) |
| 323 | (begin |
| 324 | (set-time-second! t (+ (time-second t) 1)) |
| 325 | (set-time-nanosecond! t (+ 1000000000 (time-nanosecond t)))))) |
| 326 | t) |
| 327 | |
| 328 | (define (make-time type nanosecond second) |
| 329 | (priv:time-normalize! (make-time-unnormalized type nanosecond second))) |
| 330 | |
| 331 | ;; Helpers |
| 332 | ;; FIXME: finish this and publish it? |
| 333 | (define (date->broken-down-time date) |
| 334 | (let ((result (mktime 0))) |
| 335 | ;; FIXME: What should we do about leap-seconds which may overflow |
| 336 | ;; set-tm:sec? |
| 337 | (set-tm:sec result (date-second date)) |
| 338 | (set-tm:min result (date-minute date)) |
| 339 | (set-tm:hour result (date-hour date)) |
| 340 | ;; FIXME: SRFI day ranges from 0-31. (not compatible with set-tm:mday). |
| 341 | (set-tm:mday result (date-day date)) |
| 342 | (set-tm:month result (- (date-month date) 1)) |
| 343 | ;; FIXME: need to signal error on range violation. |
| 344 | (set-tm:year result (+ 1900 (date-year date))) |
| 345 | (set-tm:isdst result -1) |
| 346 | (set-tm:gmtoff result (- (date-zone-offset date))) |
| 347 | result)) |
| 348 | |
| 349 | ;;; current-time |
| 350 | |
| 351 | ;;; specific time getters. |
| 352 | |
| 353 | (define (priv:current-time-utc) |
| 354 | ;; Resolution is microseconds. |
| 355 | (let ((tod (gettimeofday))) |
| 356 | (make-time time-utc (* (cdr tod) 1000) (car tod)))) |
| 357 | |
| 358 | (define (priv:current-time-tai) |
| 359 | ;; Resolution is microseconds. |
| 360 | (let* ((tod (gettimeofday)) |
| 361 | (sec (car tod)) |
| 362 | (usec (cdr tod))) |
| 363 | (make-time time-tai |
| 364 | (* usec 1000) |
| 365 | (+ (car tod) (priv:leap-second-delta sec))))) |
| 366 | |
| 367 | ;;(define (priv:current-time-ms-time time-type proc) |
| 368 | ;; (let ((current-ms (proc))) |
| 369 | ;; (make-time time-type |
| 370 | ;; (quotient current-ms 10000) |
| 371 | ;; (* (remainder current-ms 1000) 10000)))) |
| 372 | |
| 373 | ;; -- we define it to be the same as TAI. |
| 374 | ;; A different implemation of current-time-montonic |
| 375 | ;; will require rewriting all of the time-monotonic converters, |
| 376 | ;; of course. |
| 377 | |
| 378 | (define (priv:current-time-monotonic) |
| 379 | ;; Resolution is microseconds. |
| 380 | (priv:current-time-tai)) |
| 381 | |
| 382 | (define (priv:current-time-thread) |
| 383 | (priv:time-error 'current-time 'unsupported-clock-type 'time-thread)) |
| 384 | |
| 385 | (define priv:ns-per-guile-tick (/ 1000000000 internal-time-units-per-second)) |
| 386 | |
| 387 | (define (priv:current-time-process) |
| 388 | (let ((run-time (get-internal-run-time))) |
| 389 | (make-time |
| 390 | time-process |
| 391 | (quotient run-time internal-time-units-per-second) |
| 392 | (* (remainder run-time internal-time-units-per-second) |
| 393 | priv:ns-per-guile-tick)))) |
| 394 | |
| 395 | (define (priv:current-time-process) |
| 396 | (let ((run-time (get-internal-run-time))) |
| 397 | (list |
| 398 | 'time-process |
| 399 | (* (remainder run-time internal-time-units-per-second) |
| 400 | priv:ns-per-guile-tick) |
| 401 | (quotient run-time internal-time-units-per-second)))) |
| 402 | |
| 403 | ;;(define (priv:current-time-gc) |
| 404 | ;; (priv:current-time-ms-time time-gc current-gc-milliseconds)) |
| 405 | |
| 406 | (define (current-time . clock-type) |
| 407 | (let ((clock-type (if (null? clock-type) time-utc (car clock-type)))) |
| 408 | (cond |
| 409 | ((eq? clock-type time-tai) (priv:current-time-tai)) |
| 410 | ((eq? clock-type time-utc) (priv:current-time-utc)) |
| 411 | ((eq? clock-type time-monotonic) (priv:current-time-monotonic)) |
| 412 | ((eq? clock-type time-thread) (priv:current-time-thread)) |
| 413 | ((eq? clock-type time-process) (priv:current-time-process)) |
| 414 | ;; ((eq? clock-type time-gc) (priv:current-time-gc)) |
| 415 | (else (priv:time-error 'current-time 'invalid-clock-type clock-type))))) |
| 416 | |
| 417 | ;; -- Time Resolution |
| 418 | ;; This is the resolution of the clock in nanoseconds. |
| 419 | ;; This will be implementation specific. |
| 420 | |
| 421 | (define (time-resolution . clock-type) |
| 422 | (let ((clock-type (if (null? clock-type) time-utc (car clock-type)))) |
| 423 | (case clock-type |
| 424 | ((time-tai) 1000) |
| 425 | ((time-utc) 1000) |
| 426 | ((time-monotonic) 1000) |
| 427 | ((time-process) priv:ns-per-guile-tick) |
| 428 | ;; ((eq? clock-type time-thread) 1000) |
| 429 | ;; ((eq? clock-type time-gc) 10000) |
| 430 | (else (priv:time-error 'time-resolution 'invalid-clock-type clock-type))))) |
| 431 | |
| 432 | ;; -- Time comparisons |
| 433 | |
| 434 | (define (time=? t1 t2) |
| 435 | ;; Arrange tests for speed and presume that t1 and t2 are actually times. |
| 436 | ;; also presume it will be rare to check two times of different types. |
| 437 | (and (= (time-second t1) (time-second t2)) |
| 438 | (= (time-nanosecond t1) (time-nanosecond t2)) |
| 439 | (eq? (time-type t1) (time-type t2)))) |
| 440 | |
| 441 | (define (time>? t1 t2) |
| 442 | (or (> (time-second t1) (time-second t2)) |
| 443 | (and (= (time-second t1) (time-second t2)) |
| 444 | (> (time-nanosecond t1) (time-nanosecond t2))))) |
| 445 | |
| 446 | (define (time<? t1 t2) |
| 447 | (or (< (time-second t1) (time-second t2)) |
| 448 | (and (= (time-second t1) (time-second t2)) |
| 449 | (< (time-nanosecond t1) (time-nanosecond t2))))) |
| 450 | |
| 451 | (define (time>=? t1 t2) |
| 452 | (or (> (time-second t1) (time-second t2)) |
| 453 | (and (= (time-second t1) (time-second t2)) |
| 454 | (>= (time-nanosecond t1) (time-nanosecond t2))))) |
| 455 | |
| 456 | (define (time<=? t1 t2) |
| 457 | (or (< (time-second t1) (time-second t2)) |
| 458 | (and (= (time-second t1) (time-second t2)) |
| 459 | (<= (time-nanosecond t1) (time-nanosecond t2))))) |
| 460 | |
| 461 | ;; -- Time arithmetic |
| 462 | |
| 463 | (define (time-difference! time1 time2) |
| 464 | (let ((sec-diff (- (time-second time1) (time-second time2))) |
| 465 | (nsec-diff (- (time-nanosecond time1) (time-nanosecond time2)))) |
| 466 | (set-time-type! time1 time-duration) |
| 467 | (set-time-second! time1 sec-diff) |
| 468 | (set-time-nanosecond! time1 nsec-diff) |
| 469 | (priv:time-normalize! time1))) |
| 470 | |
| 471 | (define (time-difference time1 time2) |
| 472 | (let ((result (copy-time time1))) |
| 473 | (time-difference! result time2))) |
| 474 | |
| 475 | (define (add-duration! t duration) |
| 476 | (if (not (eq? (time-type duration) time-duration)) |
| 477 | (priv:time-error 'add-duration 'not-duration duration) |
| 478 | (let ((sec-plus (+ (time-second t) (time-second duration))) |
| 479 | (nsec-plus (+ (time-nanosecond t) (time-nanosecond duration)))) |
| 480 | (set-time-second! t sec-plus) |
| 481 | (set-time-nanosecond! t nsec-plus) |
| 482 | (priv:time-normalize! t)))) |
| 483 | |
| 484 | (define (add-duration t duration) |
| 485 | (let ((result (copy-time t))) |
| 486 | (add-duration! result duration))) |
| 487 | |
| 488 | (define (subtract-duration! t duration) |
| 489 | (if (not (eq? (time-type duration) time-duration)) |
| 490 | (priv:time-error 'add-duration 'not-duration duration) |
| 491 | (let ((sec-minus (- (time-second t) (time-second duration))) |
| 492 | (nsec-minus (- (time-nanosecond t) (time-nanosecond duration)))) |
| 493 | (set-time-second! t sec-minus) |
| 494 | (set-time-nanosecond! t nsec-minus) |
| 495 | (priv:time-normalize! t)))) |
| 496 | |
| 497 | (define (subtract-duration time1 duration) |
| 498 | (let ((result (copy-time time1))) |
| 499 | (subtract-duration! result duration))) |
| 500 | |
| 501 | ;; -- Converters between types. |
| 502 | |
| 503 | (define (priv:time-tai->time-utc! time-in time-out caller) |
| 504 | (if (not (eq? (time-type time-in) time-tai)) |
| 505 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 506 | (set-time-type! time-out time-utc) |
| 507 | (set-time-nanosecond! time-out (time-nanosecond time-in)) |
| 508 | (set-time-second! time-out (- (time-second time-in) |
| 509 | (priv:leap-second-delta |
| 510 | (time-second time-in)))) |
| 511 | time-out) |
| 512 | |
| 513 | (define (time-tai->time-utc time-in) |
| 514 | (priv:time-tai->time-utc! time-in (make-time-unnormalized #f #f #f) 'time-tai->time-utc)) |
| 515 | |
| 516 | |
| 517 | (define (time-tai->time-utc! time-in) |
| 518 | (priv:time-tai->time-utc! time-in time-in 'time-tai->time-utc!)) |
| 519 | |
| 520 | (define (priv:time-utc->time-tai! time-in time-out caller) |
| 521 | (if (not (eq? (time-type time-in) time-utc)) |
| 522 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 523 | (set-time-type! time-out time-tai) |
| 524 | (set-time-nanosecond! time-out (time-nanosecond time-in)) |
| 525 | (set-time-second! time-out (+ (time-second time-in) |
| 526 | (priv:leap-second-delta |
| 527 | (time-second time-in)))) |
| 528 | time-out) |
| 529 | |
| 530 | (define (time-utc->time-tai time-in) |
| 531 | (priv:time-utc->time-tai! time-in (make-time-unnormalized #f #f #f) 'time-utc->time-tai)) |
| 532 | |
| 533 | (define (time-utc->time-tai! time-in) |
| 534 | (priv:time-utc->time-tai! time-in time-in 'time-utc->time-tai!)) |
| 535 | |
| 536 | ;; -- these depend on time-monotonic having the same definition as time-tai! |
| 537 | (define (time-monotonic->time-utc time-in) |
| 538 | (if (not (eq? (time-type time-in) time-monotonic)) |
| 539 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 540 | (let ((ntime (copy-time time-in))) |
| 541 | (set-time-type! ntime time-tai) |
| 542 | (priv:time-tai->time-utc! ntime ntime 'time-monotonic->time-utc))) |
| 543 | |
| 544 | (define (time-monotonic->time-utc! time-in) |
| 545 | (if (not (eq? (time-type time-in) time-monotonic)) |
| 546 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 547 | (set-time-type! time-in time-tai) |
| 548 | (priv:time-tai->time-utc! ntime ntime 'time-monotonic->time-utc)) |
| 549 | |
| 550 | (define (time-monotonic->time-tai time-in) |
| 551 | (if (not (eq? (time-type time-in) time-monotonic)) |
| 552 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 553 | (let ((ntime (copy-time time-in))) |
| 554 | (set-time-type! ntime time-tai) |
| 555 | ntime)) |
| 556 | |
| 557 | (define (time-monotonic->time-tai! time-in) |
| 558 | (if (not (eq? (time-type time-in) time-monotonic)) |
| 559 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 560 | (set-time-type! time-in time-tai) |
| 561 | time-in) |
| 562 | |
| 563 | (define (time-utc->time-monotonic time-in) |
| 564 | (if (not (eq? (time-type time-in) time-utc)) |
| 565 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 566 | (let ((ntime (priv:time-utc->time-tai! time-in (make-time-unnormalized #f #f #f) |
| 567 | 'time-utc->time-monotonic))) |
| 568 | (set-time-type! ntime time-monotonic) |
| 569 | ntime)) |
| 570 | |
| 571 | (define (time-utc->time-monotonic! time-in) |
| 572 | (if (not (eq? (time-type time-in) time-utc)) |
| 573 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 574 | (let ((ntime (priv:time-utc->time-tai! time-in time-in |
| 575 | 'time-utc->time-monotonic!))) |
| 576 | (set-time-type! ntime time-monotonic) |
| 577 | ntime)) |
| 578 | |
| 579 | (define (time-tai->time-monotonic time-in) |
| 580 | (if (not (eq? (time-type time-in) time-tai)) |
| 581 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 582 | (let ((ntime (copy-time time-in))) |
| 583 | (set-time-type! ntime time-monotonic) |
| 584 | ntime)) |
| 585 | |
| 586 | (define (time-tai->time-monotonic! time-in) |
| 587 | (if (not (eq? (time-type time-in) time-tai)) |
| 588 | (priv:time-error caller 'incompatible-time-types time-in)) |
| 589 | (set-time-type! time-in time-monotonic) |
| 590 | time-in) |
| 591 | |
| 592 | ;; -- Date Structures |
| 593 | |
| 594 | ;; FIXME: to be really safe, perhaps we should normalize the |
| 595 | ;; seconds/nanoseconds/minutes coming in to make-date... |
| 596 | |
| 597 | (define-record-type date |
| 598 | (make-date nanosecond second minute |
| 599 | hour day month |
| 600 | year |
| 601 | zone-offset) |
| 602 | date? |
| 603 | (nanosecond date-nanosecond set-date-nanosecond!) |
| 604 | (second date-second set-date-second!) |
| 605 | (minute date-minute set-date-minute!) |
| 606 | (hour date-hour set-date-hour!) |
| 607 | (day date-day set-date-day!) |
| 608 | (month date-month set-date-month!) |
| 609 | (year date-year set-date-year!) |
| 610 | (zone-offset date-zone-offset set-date-zone-offset!)) |
| 611 | |
| 612 | ;; gives the julian day which starts at noon. |
| 613 | (define (priv:encode-julian-day-number day month year) |
| 614 | (let* ((a (quotient (- 14 month) 12)) |
| 615 | (y (- (+ year 4800) a (if (negative? year) -1 0))) |
| 616 | (m (- (+ month (* 12 a)) 3))) |
| 617 | (+ day |
| 618 | (quotient (+ (* 153 m) 2) 5) |
| 619 | (* 365 y) |
| 620 | (quotient y 4) |
| 621 | (- (quotient y 100)) |
| 622 | (quotient y 400) |
| 623 | -32045))) |
| 624 | |
| 625 | ;; gives the seconds/date/month/year |
| 626 | (define (priv:decode-julian-day-number jdn) |
| 627 | (let* ((days (inexact->exact (truncate jdn))) |
| 628 | (a (+ days 32044)) |
| 629 | (b (quotient (+ (* 4 a) 3) 146097)) |
| 630 | (c (- a (quotient (* 146097 b) 4))) |
| 631 | (d (quotient (+ (* 4 c) 3) 1461)) |
| 632 | (e (- c (quotient (* 1461 d) 4))) |
| 633 | (m (quotient (+ (* 5 e) 2) 153)) |
| 634 | (y (+ (* 100 b) d -4800 (quotient m 10)))) |
| 635 | (values ; seconds date month year |
| 636 | (* (- jdn days) priv:sid) |
| 637 | (+ e (- (quotient (+ (* 153 m) 2) 5)) 1) |
| 638 | (+ m 3 (* -12 (quotient m 10))) |
| 639 | (if (>= 0 y) (- y 1) y)))) |
| 640 | |
| 641 | ;; relies on the fact that we named our time zone accessor |
| 642 | ;; differently from MzScheme's.... |
| 643 | ;; This should be written to be OS specific. |
| 644 | |
| 645 | (define (priv:local-tz-offset utc-time) |
| 646 | ;; SRFI uses seconds West, but guile (and libc) use seconds East. |
| 647 | (- (tm:gmtoff (localtime (time-second utc-time))))) |
| 648 | |
| 649 | ;; special thing -- ignores nanos |
| 650 | (define (priv:time->julian-day-number seconds tz-offset) |
| 651 | (+ (/ (+ seconds tz-offset priv:sihd) |
| 652 | priv:sid) |
| 653 | priv:tai-epoch-in-jd)) |
| 654 | |
| 655 | (define (priv:leap-second? second) |
| 656 | (and (assoc second priv:leap-second-table) #t)) |
| 657 | |
| 658 | (define (time-utc->date time . tz-offset) |
| 659 | (if (not (eq? (time-type time) time-utc)) |
| 660 | (priv:time-error 'time->date 'incompatible-time-types time)) |
| 661 | (let* ((offset (if (null? tz-offset) |
| 662 | (priv:local-tz-offset time) |
| 663 | (car tz-offset))) |
| 664 | (leap-second? (priv:leap-second? (+ offset (time-second time)))) |
| 665 | (jdn (priv:time->julian-day-number (if leap-second? |
| 666 | (- (time-second time) 1) |
| 667 | (time-second time)) |
| 668 | offset))) |
| 669 | |
| 670 | (call-with-values (lambda () (priv:decode-julian-day-number jdn)) |
| 671 | (lambda (secs date month year) |
| 672 | ;; secs is a real because jdn is a real in Guile; |
| 673 | ;; but it is conceptionally an integer. |
| 674 | (let* ((int-secs (inexact->exact (round secs))) |
| 675 | (hours (quotient int-secs (* 60 60))) |
| 676 | (rem (remainder int-secs (* 60 60))) |
| 677 | (minutes (quotient rem 60)) |
| 678 | (seconds (remainder rem 60))) |
| 679 | (make-date (time-nanosecond time) |
| 680 | (if leap-second? (+ seconds 1) seconds) |
| 681 | minutes |
| 682 | hours |
| 683 | date |
| 684 | month |
| 685 | year |
| 686 | offset)))))) |
| 687 | |
| 688 | (define (time-tai->date time . tz-offset) |
| 689 | (if (not (eq? (time-type time) time-tai)) |
| 690 | (priv:time-error 'time->date 'incompatible-time-types time)) |
| 691 | (let* ((offset (if (null? tz-offset) |
| 692 | (priv:local-tz-offset (time-tai->time-utc time)) |
| 693 | (car tz-offset))) |
| 694 | (seconds (- (time-second time) |
| 695 | (priv:leap-second-delta (time-second time)))) |
| 696 | (leap-second? (priv:leap-second? (+ offset seconds))) |
| 697 | (jdn (priv:time->julian-day-number (if leap-second? |
| 698 | (- seconds 1) |
| 699 | seconds) |
| 700 | offset))) |
| 701 | (call-with-values (lambda () (priv:decode-julian-day-number jdn)) |
| 702 | (lambda (secs date month year) |
| 703 | ;; secs is a real because jdn is a real in Guile; |
| 704 | ;; but it is conceptionally an integer. |
| 705 | ;; adjust for leap seconds if necessary ... |
| 706 | (let* ((int-secs (inexact->exact (round secs))) |
| 707 | (hours (quotient int-secs (* 60 60))) |
| 708 | (rem (remainder int-secs (* 60 60))) |
| 709 | (minutes (quotient rem 60)) |
| 710 | (seconds (remainder rem 60))) |
| 711 | (make-date (time-nanosecond time) |
| 712 | (if leap-second? (+ seconds 1) seconds) |
| 713 | minutes |
| 714 | hours |
| 715 | date |
| 716 | month |
| 717 | year |
| 718 | offset)))))) |
| 719 | |
| 720 | ;; this is the same as time-tai->date. |
| 721 | (define (time-monotonic->date time . tz-offset) |
| 722 | (if (not (eq? (time-type time) time-monotonic)) |
| 723 | (priv:time-error 'time->date 'incompatible-time-types time)) |
| 724 | (let* ((offset (if (null? tz-offset) |
| 725 | (priv:local-tz-offset (time-monotonic->time-utc time)) |
| 726 | (car tz-offset))) |
| 727 | (seconds (- (time-second time) |
| 728 | (priv:leap-second-delta (time-second time)))) |
| 729 | (leap-second? (priv:leap-second? (+ offset seconds))) |
| 730 | (jdn (priv:time->julian-day-number (if leap-second? |
| 731 | (- seconds 1) |
| 732 | seconds) |
| 733 | offset))) |
| 734 | (call-with-values (lambda () (priv:decode-julian-day-number jdn)) |
| 735 | (lambda (secs date month year) |
| 736 | ;; secs is a real because jdn is a real in Guile; |
| 737 | ;; but it is conceptionally an integer. |
| 738 | ;; adjust for leap seconds if necessary ... |
| 739 | (let* ((int-secs (inexact->exact (round secs))) |
| 740 | (hours (quotient int-secs (* 60 60))) |
| 741 | (rem (remainder int-secs (* 60 60))) |
| 742 | (minutes (quotient rem 60)) |
| 743 | (seconds (remainder rem 60))) |
| 744 | (make-date (time-nanosecond time) |
| 745 | (if leap-second? (+ seconds 1) seconds) |
| 746 | minutes |
| 747 | hours |
| 748 | date |
| 749 | month |
| 750 | year |
| 751 | offset)))))) |
| 752 | |
| 753 | (define (date->time-utc date) |
| 754 | (let* ((jdays (- (priv:encode-julian-day-number (date-day date) |
| 755 | (date-month date) |
| 756 | (date-year date)) |
| 757 | priv:tai-epoch-in-jd)) |
| 758 | ;; jdays is an integer plus 1/2, |
| 759 | (jdays-1/2 (inexact->exact (- jdays 1/2)))) |
| 760 | (make-time |
| 761 | time-utc |
| 762 | (date-nanosecond date) |
| 763 | (+ (* jdays-1/2 24 60 60) |
| 764 | (* (date-hour date) 60 60) |
| 765 | (* (date-minute date) 60) |
| 766 | (date-second date) |
| 767 | (- (date-zone-offset date)))))) |
| 768 | |
| 769 | (define (date->time-tai date) |
| 770 | (time-utc->time-tai! (date->time-utc date))) |
| 771 | |
| 772 | (define (date->time-monotonic date) |
| 773 | (time-utc->time-monotonic! (date->time-utc date))) |
| 774 | |
| 775 | (define (priv:leap-year? year) |
| 776 | (or (= (modulo year 400) 0) |
| 777 | (and (= (modulo year 4) 0) (not (= (modulo year 100) 0))))) |
| 778 | |
| 779 | (define (leap-year? date) |
| 780 | (priv:leap-year? (date-year date))) |
| 781 | |
| 782 | ;; Map 1-based month number M to number of days in the year before the |
| 783 | ;; start of month M (in a non-leap year). |
| 784 | (define priv:month-assoc '((1 . 0) (2 . 31) (3 . 59) (4 . 90) |
| 785 | (5 . 120) (6 . 151) (7 . 181) (8 . 212) |
| 786 | (9 . 243) (10 . 273) (11 . 304) (12 . 334))) |
| 787 | |
| 788 | (define (priv:year-day day month year) |
| 789 | (let ((days-pr (assoc month priv:month-assoc))) |
| 790 | (if (not days-pr) |
| 791 | (priv:error 'date-year-day 'invalid-month-specification month)) |
| 792 | (if (and (priv:leap-year? year) (> month 2)) |
| 793 | (+ day (cdr days-pr) 1) |
| 794 | (+ day (cdr days-pr))))) |
| 795 | |
| 796 | (define (date-year-day date) |
| 797 | (priv:year-day (date-day date) (date-month date) (date-year date))) |
| 798 | |
| 799 | ;; from calendar faq |
| 800 | (define (priv:week-day day month year) |
| 801 | (let* ((a (quotient (- 14 month) 12)) |
| 802 | (y (- year a)) |
| 803 | (m (+ month (* 12 a) -2))) |
| 804 | (modulo (+ day |
| 805 | y |
| 806 | (quotient y 4) |
| 807 | (- (quotient y 100)) |
| 808 | (quotient y 400) |
| 809 | (quotient (* 31 m) 12)) |
| 810 | 7))) |
| 811 | |
| 812 | (define (date-week-day date) |
| 813 | (priv:week-day (date-day date) (date-month date) (date-year date))) |
| 814 | |
| 815 | (define (priv:days-before-first-week date day-of-week-starting-week) |
| 816 | (let* ((first-day (make-date 0 0 0 0 |
| 817 | 1 |
| 818 | 1 |
| 819 | (date-year date) |
| 820 | #f)) |
| 821 | (fdweek-day (date-week-day first-day))) |
| 822 | (modulo (- day-of-week-starting-week fdweek-day) |
| 823 | 7))) |
| 824 | |
| 825 | ;; The "-1" here is a fix for the reference implementation, to make a new |
| 826 | ;; week start on the given day-of-week-starting-week. date-year-day returns |
| 827 | ;; a day starting from 1 for 1st Jan. |
| 828 | ;; |
| 829 | (define (date-week-number date day-of-week-starting-week) |
| 830 | (quotient (- (date-year-day date) |
| 831 | 1 |
| 832 | (priv:days-before-first-week date day-of-week-starting-week)) |
| 833 | 7)) |
| 834 | |
| 835 | (define (current-date . tz-offset) |
| 836 | (let ((time (current-time time-utc))) |
| 837 | (time-utc->date |
| 838 | time |
| 839 | (if (null? tz-offset) |
| 840 | (priv:local-tz-offset time) |
| 841 | (car tz-offset))))) |
| 842 | |
| 843 | ;; given a 'two digit' number, find the year within 50 years +/- |
| 844 | (define (priv:natural-year n) |
| 845 | (let* ((current-year (date-year (current-date))) |
| 846 | (current-century (* (quotient current-year 100) 100))) |
| 847 | (cond |
| 848 | ((>= n 100) n) |
| 849 | ((< n 0) n) |
| 850 | ((<= (- (+ current-century n) current-year) 50) (+ current-century n)) |
| 851 | (else (+ (- current-century 100) n))))) |
| 852 | |
| 853 | (define (date->julian-day date) |
| 854 | (let ((nanosecond (date-nanosecond date)) |
| 855 | (second (date-second date)) |
| 856 | (minute (date-minute date)) |
| 857 | (hour (date-hour date)) |
| 858 | (day (date-day date)) |
| 859 | (month (date-month date)) |
| 860 | (year (date-year date))) |
| 861 | (+ (priv:encode-julian-day-number day month year) |
| 862 | (- 1/2) |
| 863 | (+ (/ (+ (* hour 60 60) |
| 864 | (* minute 60) |
| 865 | second |
| 866 | (/ nanosecond priv:nano)) |
| 867 | priv:sid))))) |
| 868 | |
| 869 | (define (date->modified-julian-day date) |
| 870 | (- (date->julian-day date) |
| 871 | 4800001/2)) |
| 872 | |
| 873 | (define (time-utc->julian-day time) |
| 874 | (if (not (eq? (time-type time) time-utc)) |
| 875 | (priv:time-error 'time->date 'incompatible-time-types time)) |
| 876 | (+ (/ (+ (time-second time) (/ (time-nanosecond time) priv:nano)) |
| 877 | priv:sid) |
| 878 | priv:tai-epoch-in-jd)) |
| 879 | |
| 880 | (define (time-utc->modified-julian-day time) |
| 881 | (- (time-utc->julian-day time) |
| 882 | 4800001/2)) |
| 883 | |
| 884 | (define (time-tai->julian-day time) |
| 885 | (if (not (eq? (time-type time) time-tai)) |
| 886 | (priv:time-error 'time->date 'incompatible-time-types time)) |
| 887 | (+ (/ (+ (- (time-second time) |
| 888 | (priv:leap-second-delta (time-second time))) |
| 889 | (/ (time-nanosecond time) priv:nano)) |
| 890 | priv:sid) |
| 891 | priv:tai-epoch-in-jd)) |
| 892 | |
| 893 | (define (time-tai->modified-julian-day time) |
| 894 | (- (time-tai->julian-day time) |
| 895 | 4800001/2)) |
| 896 | |
| 897 | ;; this is the same as time-tai->julian-day |
| 898 | (define (time-monotonic->julian-day time) |
| 899 | (if (not (eq? (time-type time) time-monotonic)) |
| 900 | (priv:time-error 'time->date 'incompatible-time-types time)) |
| 901 | (+ (/ (+ (- (time-second time) |
| 902 | (priv:leap-second-delta (time-second time))) |
| 903 | (/ (time-nanosecond time) priv:nano)) |
| 904 | priv:sid) |
| 905 | priv:tai-epoch-in-jd)) |
| 906 | |
| 907 | (define (time-monotonic->modified-julian-day time) |
| 908 | (- (time-monotonic->julian-day time) |
| 909 | 4800001/2)) |
| 910 | |
| 911 | (define (julian-day->time-utc jdn) |
| 912 | (let ((secs (* priv:sid (- jdn priv:tai-epoch-in-jd)))) |
| 913 | (receive (seconds parts) |
| 914 | (priv:split-real secs) |
| 915 | (make-time time-utc |
| 916 | (* parts priv:nano) |
| 917 | seconds)))) |
| 918 | |
| 919 | (define (julian-day->time-tai jdn) |
| 920 | (time-utc->time-tai! (julian-day->time-utc jdn))) |
| 921 | |
| 922 | (define (julian-day->time-monotonic jdn) |
| 923 | (time-utc->time-monotonic! (julian-day->time-utc jdn))) |
| 924 | |
| 925 | (define (julian-day->date jdn . tz-offset) |
| 926 | (let* ((time (julian-day->time-utc jdn)) |
| 927 | (offset (if (null? tz-offset) |
| 928 | (priv:local-tz-offset time) |
| 929 | (car tz-offset)))) |
| 930 | (time-utc->date time offset))) |
| 931 | |
| 932 | (define (modified-julian-day->date jdn . tz-offset) |
| 933 | (apply julian-day->date (+ jdn 4800001/2) |
| 934 | tz-offset)) |
| 935 | |
| 936 | (define (modified-julian-day->time-utc jdn) |
| 937 | (julian-day->time-utc (+ jdn 4800001/2))) |
| 938 | |
| 939 | (define (modified-julian-day->time-tai jdn) |
| 940 | (julian-day->time-tai (+ jdn 4800001/2))) |
| 941 | |
| 942 | (define (modified-julian-day->time-monotonic jdn) |
| 943 | (julian-day->time-monotonic (+ jdn 4800001/2))) |
| 944 | |
| 945 | (define (current-julian-day) |
| 946 | (time-utc->julian-day (current-time time-utc))) |
| 947 | |
| 948 | (define (current-modified-julian-day) |
| 949 | (time-utc->modified-julian-day (current-time time-utc))) |
| 950 | |
| 951 | ;; returns a string rep. of number N, of minimum LENGTH, padded with |
| 952 | ;; character PAD-WITH. If PAD-WITH is #f, no padding is done, and it's |
| 953 | ;; as if number->string was used. if string is longer than or equal |
| 954 | ;; in length to LENGTH, it's as if number->string was used. |
| 955 | |
| 956 | (define (priv:padding n pad-with length) |
| 957 | (let* ((str (number->string n)) |
| 958 | (str-len (string-length str))) |
| 959 | (if (or (>= str-len length) |
| 960 | (not pad-with)) |
| 961 | str |
| 962 | (string-append (make-string (- length str-len) pad-with) str)))) |
| 963 | |
| 964 | (define (priv:last-n-digits i n) |
| 965 | (abs (remainder i (expt 10 n)))) |
| 966 | |
| 967 | (define (priv:locale-abbr-weekday n) |
| 968 | (vector-ref priv:locale-abbr-weekday-vector n)) |
| 969 | |
| 970 | (define (priv:locale-long-weekday n) |
| 971 | (vector-ref priv:locale-long-weekday-vector n)) |
| 972 | |
| 973 | (define (priv:locale-abbr-month n) |
| 974 | (vector-ref priv:locale-abbr-month-vector n)) |
| 975 | |
| 976 | (define (priv:locale-long-month n) |
| 977 | (vector-ref priv:locale-long-month-vector n)) |
| 978 | |
| 979 | (define (priv:vector-find needle haystack comparator) |
| 980 | (let ((len (vector-length haystack))) |
| 981 | (define (priv:vector-find-int index) |
| 982 | (cond |
| 983 | ((>= index len) #f) |
| 984 | ((comparator needle (vector-ref haystack index)) index) |
| 985 | (else (priv:vector-find-int (+ index 1))))) |
| 986 | (priv:vector-find-int 0))) |
| 987 | |
| 988 | (define (priv:locale-abbr-weekday->index string) |
| 989 | (priv:vector-find string priv:locale-abbr-weekday-vector string=?)) |
| 990 | |
| 991 | (define (priv:locale-long-weekday->index string) |
| 992 | (priv:vector-find string priv:locale-long-weekday-vector string=?)) |
| 993 | |
| 994 | (define (priv:locale-abbr-month->index string) |
| 995 | (priv:vector-find string priv:locale-abbr-month-vector string=?)) |
| 996 | |
| 997 | (define (priv:locale-long-month->index string) |
| 998 | (priv:vector-find string priv:locale-long-month-vector string=?)) |
| 999 | |
| 1000 | |
| 1001 | ;; FIXME: mkoeppe: Put a symbolic time zone in the date structs. |
| 1002 | ;; Print it here instead of the numerical offset if available. |
| 1003 | (define (priv:locale-print-time-zone date port) |
| 1004 | (priv:tz-printer (date-zone-offset date) port)) |
| 1005 | |
| 1006 | ;; FIXME: we should use strftime to determine this dynamically if possible. |
| 1007 | ;; Again, locale specific. |
| 1008 | (define (priv:locale-am/pm hr) |
| 1009 | (if (> hr 11) priv:locale-pm priv:locale-am)) |
| 1010 | |
| 1011 | (define (priv:tz-printer offset port) |
| 1012 | (cond |
| 1013 | ((= offset 0) (display "Z" port)) |
| 1014 | ((negative? offset) (display "-" port)) |
| 1015 | (else (display "+" port))) |
| 1016 | (if (not (= offset 0)) |
| 1017 | (let ((hours (abs (quotient offset (* 60 60)))) |
| 1018 | (minutes (abs (quotient (remainder offset (* 60 60)) 60)))) |
| 1019 | (display (priv:padding hours #\0 2) port) |
| 1020 | (display (priv:padding minutes #\0 2) port)))) |
| 1021 | |
| 1022 | ;; A table of output formatting directives. |
| 1023 | ;; the first time is the format char. |
| 1024 | ;; the second is a procedure that takes the date, a padding character |
| 1025 | ;; (which might be #f), and the output port. |
| 1026 | ;; |
| 1027 | (define priv:directives |
| 1028 | (list |
| 1029 | (cons #\~ (lambda (date pad-with port) |
| 1030 | (display #\~ port))) |
| 1031 | (cons #\a (lambda (date pad-with port) |
| 1032 | (display (priv:locale-abbr-weekday (date-week-day date)) |
| 1033 | port))) |
| 1034 | (cons #\A (lambda (date pad-with port) |
| 1035 | (display (priv:locale-long-weekday (date-week-day date)) |
| 1036 | port))) |
| 1037 | (cons #\b (lambda (date pad-with port) |
| 1038 | (display (priv:locale-abbr-month (date-month date)) |
| 1039 | port))) |
| 1040 | (cons #\B (lambda (date pad-with port) |
| 1041 | (display (priv:locale-long-month (date-month date)) |
| 1042 | port))) |
| 1043 | (cons #\c (lambda (date pad-with port) |
| 1044 | (display (date->string date priv:locale-date-time-format) port))) |
| 1045 | (cons #\d (lambda (date pad-with port) |
| 1046 | (display (priv:padding (date-day date) |
| 1047 | #\0 2) |
| 1048 | port))) |
| 1049 | (cons #\D (lambda (date pad-with port) |
| 1050 | (display (date->string date "~m/~d/~y") port))) |
| 1051 | (cons #\e (lambda (date pad-with port) |
| 1052 | (display (priv:padding (date-day date) |
| 1053 | #\Space 2) |
| 1054 | port))) |
| 1055 | (cons #\f (lambda (date pad-with port) |
| 1056 | (if (> (date-nanosecond date) |
| 1057 | priv:nano) |
| 1058 | (display (priv:padding (+ (date-second date) 1) |
| 1059 | pad-with 2) |
| 1060 | port) |
| 1061 | (display (priv:padding (date-second date) |
| 1062 | pad-with 2) |
| 1063 | port)) |
| 1064 | (receive (i f) |
| 1065 | (priv:split-real (/ |
| 1066 | (date-nanosecond date) |
| 1067 | priv:nano 1.0)) |
| 1068 | (let* ((ns (number->string f)) |
| 1069 | (le (string-length ns))) |
| 1070 | (if (> le 2) |
| 1071 | (begin |
| 1072 | (display priv:locale-number-separator port) |
| 1073 | (display (substring ns 2 le) port))))))) |
| 1074 | (cons #\h (lambda (date pad-with port) |
| 1075 | (display (date->string date "~b") port))) |
| 1076 | (cons #\H (lambda (date pad-with port) |
| 1077 | (display (priv:padding (date-hour date) |
| 1078 | pad-with 2) |
| 1079 | port))) |
| 1080 | (cons #\I (lambda (date pad-with port) |
| 1081 | (let ((hr (date-hour date))) |
| 1082 | (if (> hr 12) |
| 1083 | (display (priv:padding (- hr 12) |
| 1084 | pad-with 2) |
| 1085 | port) |
| 1086 | (display (priv:padding hr |
| 1087 | pad-with 2) |
| 1088 | port))))) |
| 1089 | (cons #\j (lambda (date pad-with port) |
| 1090 | (display (priv:padding (date-year-day date) |
| 1091 | pad-with 3) |
| 1092 | port))) |
| 1093 | (cons #\k (lambda (date pad-with port) |
| 1094 | (display (priv:padding (date-hour date) |
| 1095 | #\Space 2) |
| 1096 | port))) |
| 1097 | (cons #\l (lambda (date pad-with port) |
| 1098 | (let ((hr (if (> (date-hour date) 12) |
| 1099 | (- (date-hour date) 12) (date-hour date)))) |
| 1100 | (display (priv:padding hr #\Space 2) |
| 1101 | port)))) |
| 1102 | (cons #\m (lambda (date pad-with port) |
| 1103 | (display (priv:padding (date-month date) |
| 1104 | pad-with 2) |
| 1105 | port))) |
| 1106 | (cons #\M (lambda (date pad-with port) |
| 1107 | (display (priv:padding (date-minute date) |
| 1108 | pad-with 2) |
| 1109 | port))) |
| 1110 | (cons #\n (lambda (date pad-with port) |
| 1111 | (newline port))) |
| 1112 | (cons #\N (lambda (date pad-with port) |
| 1113 | (display (priv:padding (date-nanosecond date) |
| 1114 | pad-with 7) |
| 1115 | port))) |
| 1116 | (cons #\p (lambda (date pad-with port) |
| 1117 | (display (priv:locale-am/pm (date-hour date)) port))) |
| 1118 | (cons #\r (lambda (date pad-with port) |
| 1119 | (display (date->string date "~I:~M:~S ~p") port))) |
| 1120 | (cons #\s (lambda (date pad-with port) |
| 1121 | (display (time-second (date->time-utc date)) port))) |
| 1122 | (cons #\S (lambda (date pad-with port) |
| 1123 | (if (> (date-nanosecond date) |
| 1124 | priv:nano) |
| 1125 | (display (priv:padding (+ (date-second date) 1) |
| 1126 | pad-with 2) |
| 1127 | port) |
| 1128 | (display (priv:padding (date-second date) |
| 1129 | pad-with 2) |
| 1130 | port)))) |
| 1131 | (cons #\t (lambda (date pad-with port) |
| 1132 | (display #\Tab port))) |
| 1133 | (cons #\T (lambda (date pad-with port) |
| 1134 | (display (date->string date "~H:~M:~S") port))) |
| 1135 | (cons #\U (lambda (date pad-with port) |
| 1136 | (if (> (priv:days-before-first-week date 0) 0) |
| 1137 | (display (priv:padding (+ (date-week-number date 0) 1) |
| 1138 | #\0 2) port) |
| 1139 | (display (priv:padding (date-week-number date 0) |
| 1140 | #\0 2) port)))) |
| 1141 | (cons #\V (lambda (date pad-with port) |
| 1142 | (display (priv:padding (date-week-number date 1) |
| 1143 | #\0 2) port))) |
| 1144 | (cons #\w (lambda (date pad-with port) |
| 1145 | (display (date-week-day date) port))) |
| 1146 | (cons #\x (lambda (date pad-with port) |
| 1147 | (display (date->string date priv:locale-short-date-format) port))) |
| 1148 | (cons #\X (lambda (date pad-with port) |
| 1149 | (display (date->string date priv:locale-time-format) port))) |
| 1150 | (cons #\W (lambda (date pad-with port) |
| 1151 | (if (> (priv:days-before-first-week date 1) 0) |
| 1152 | (display (priv:padding (+ (date-week-number date 1) 1) |
| 1153 | #\0 2) port) |
| 1154 | (display (priv:padding (date-week-number date 1) |
| 1155 | #\0 2) port)))) |
| 1156 | (cons #\y (lambda (date pad-with port) |
| 1157 | (display (priv:padding (priv:last-n-digits |
| 1158 | (date-year date) 2) |
| 1159 | pad-with |
| 1160 | 2) |
| 1161 | port))) |
| 1162 | (cons #\Y (lambda (date pad-with port) |
| 1163 | (display (date-year date) port))) |
| 1164 | (cons #\z (lambda (date pad-with port) |
| 1165 | (priv:tz-printer (date-zone-offset date) port))) |
| 1166 | (cons #\Z (lambda (date pad-with port) |
| 1167 | (priv:locale-print-time-zone date port))) |
| 1168 | (cons #\1 (lambda (date pad-with port) |
| 1169 | (display (date->string date "~Y-~m-~d") port))) |
| 1170 | (cons #\2 (lambda (date pad-with port) |
| 1171 | (display (date->string date "~k:~M:~S~z") port))) |
| 1172 | (cons #\3 (lambda (date pad-with port) |
| 1173 | (display (date->string date "~k:~M:~S") port))) |
| 1174 | (cons #\4 (lambda (date pad-with port) |
| 1175 | (display (date->string date "~Y-~m-~dT~k:~M:~S~z") port))) |
| 1176 | (cons #\5 (lambda (date pad-with port) |
| 1177 | (display (date->string date "~Y-~m-~dT~k:~M:~S") port))))) |
| 1178 | |
| 1179 | |
| 1180 | (define (priv:get-formatter char) |
| 1181 | (let ((associated (assoc char priv:directives))) |
| 1182 | (if associated (cdr associated) #f))) |
| 1183 | |
| 1184 | (define (priv:date-printer date index format-string str-len port) |
| 1185 | (if (>= index str-len) |
| 1186 | (values) |
| 1187 | (let ((current-char (string-ref format-string index))) |
| 1188 | (if (not (char=? current-char #\~)) |
| 1189 | (begin |
| 1190 | (display current-char port) |
| 1191 | (priv:date-printer date (+ index 1) format-string str-len port)) |
| 1192 | (if (= (+ index 1) str-len) ; bad format string. |
| 1193 | (priv:time-error 'priv:date-printer 'bad-date-format-string |
| 1194 | format-string) |
| 1195 | (let ((pad-char? (string-ref format-string (+ index 1)))) |
| 1196 | (cond |
| 1197 | ((char=? pad-char? #\-) |
| 1198 | (if (= (+ index 2) str-len) ; bad format string. |
| 1199 | (priv:time-error 'priv:date-printer |
| 1200 | 'bad-date-format-string |
| 1201 | format-string) |
| 1202 | (let ((formatter (priv:get-formatter |
| 1203 | (string-ref format-string |
| 1204 | (+ index 2))))) |
| 1205 | (if (not formatter) |
| 1206 | (priv:time-error 'priv:date-printer |
| 1207 | 'bad-date-format-string |
| 1208 | format-string) |
| 1209 | (begin |
| 1210 | (formatter date #f port) |
| 1211 | (priv:date-printer date |
| 1212 | (+ index 3) |
| 1213 | format-string |
| 1214 | str-len |
| 1215 | port)))))) |
| 1216 | |
| 1217 | ((char=? pad-char? #\_) |
| 1218 | (if (= (+ index 2) str-len) ; bad format string. |
| 1219 | (priv:time-error 'priv:date-printer |
| 1220 | 'bad-date-format-string |
| 1221 | format-string) |
| 1222 | (let ((formatter (priv:get-formatter |
| 1223 | (string-ref format-string |
| 1224 | (+ index 2))))) |
| 1225 | (if (not formatter) |
| 1226 | (priv:time-error 'priv:date-printer |
| 1227 | 'bad-date-format-string |
| 1228 | format-string) |
| 1229 | (begin |
| 1230 | (formatter date #\Space port) |
| 1231 | (priv:date-printer date |
| 1232 | (+ index 3) |
| 1233 | format-string |
| 1234 | str-len |
| 1235 | port)))))) |
| 1236 | (else |
| 1237 | (let ((formatter (priv:get-formatter |
| 1238 | (string-ref format-string |
| 1239 | (+ index 1))))) |
| 1240 | (if (not formatter) |
| 1241 | (priv:time-error 'priv:date-printer |
| 1242 | 'bad-date-format-string |
| 1243 | format-string) |
| 1244 | (begin |
| 1245 | (formatter date #\0 port) |
| 1246 | (priv:date-printer date |
| 1247 | (+ index 2) |
| 1248 | format-string |
| 1249 | str-len |
| 1250 | port)))))))))))) |
| 1251 | |
| 1252 | |
| 1253 | (define (date->string date . format-string) |
| 1254 | (let ((str-port (open-output-string)) |
| 1255 | (fmt-str (if (null? format-string) "~c" (car format-string)))) |
| 1256 | (priv:date-printer date 0 fmt-str (string-length fmt-str) str-port) |
| 1257 | (get-output-string str-port))) |
| 1258 | |
| 1259 | (define (priv:char->int ch) |
| 1260 | (case ch |
| 1261 | ((#\0) 0) |
| 1262 | ((#\1) 1) |
| 1263 | ((#\2) 2) |
| 1264 | ((#\3) 3) |
| 1265 | ((#\4) 4) |
| 1266 | ((#\5) 5) |
| 1267 | ((#\6) 6) |
| 1268 | ((#\7) 7) |
| 1269 | ((#\8) 8) |
| 1270 | ((#\9) 9) |
| 1271 | (else (priv:time-error 'bad-date-template-string |
| 1272 | (list "Non-integer character" ch i))))) |
| 1273 | |
| 1274 | ;; read an integer upto n characters long on port; upto -> #f is any length |
| 1275 | (define (priv:integer-reader upto port) |
| 1276 | (let loop ((accum 0) (nchars 0)) |
| 1277 | (let ((ch (peek-char port))) |
| 1278 | (if (or (eof-object? ch) |
| 1279 | (not (char-numeric? ch)) |
| 1280 | (and upto (>= nchars upto))) |
| 1281 | accum |
| 1282 | (loop (+ (* accum 10) (priv:char->int (read-char port))) |
| 1283 | (+ nchars 1)))))) |
| 1284 | |
| 1285 | (define (priv:make-integer-reader upto) |
| 1286 | (lambda (port) |
| 1287 | (priv:integer-reader upto port))) |
| 1288 | |
| 1289 | ;; read *exactly* n characters and convert to integer; could be padded |
| 1290 | (define (priv:integer-reader-exact n port) |
| 1291 | (let ((padding-ok #t)) |
| 1292 | (define (accum-int port accum nchars) |
| 1293 | (let ((ch (peek-char port))) |
| 1294 | (cond |
| 1295 | ((>= nchars n) accum) |
| 1296 | ((eof-object? ch) |
| 1297 | (priv:time-error 'string->date 'bad-date-template-string |
| 1298 | "Premature ending to integer read.")) |
| 1299 | ((char-numeric? ch) |
| 1300 | (set! padding-ok #f) |
| 1301 | (accum-int port |
| 1302 | (+ (* accum 10) (priv:char->int (read-char port))) |
| 1303 | (+ nchars 1))) |
| 1304 | (padding-ok |
| 1305 | (read-char port) ; consume padding |
| 1306 | (accum-int port accum (+ nchars 1))) |
| 1307 | (else ; padding where it shouldn't be |
| 1308 | (priv:time-error 'string->date 'bad-date-template-string |
| 1309 | "Non-numeric characters in integer read."))))) |
| 1310 | (accum-int port 0 0))) |
| 1311 | |
| 1312 | |
| 1313 | (define (priv:make-integer-exact-reader n) |
| 1314 | (lambda (port) |
| 1315 | (priv:integer-reader-exact n port))) |
| 1316 | |
| 1317 | (define (priv:zone-reader port) |
| 1318 | (let ((offset 0) |
| 1319 | (positive? #f)) |
| 1320 | (let ((ch (read-char port))) |
| 1321 | (if (eof-object? ch) |
| 1322 | (priv:time-error 'string->date 'bad-date-template-string |
| 1323 | (list "Invalid time zone +/-" ch))) |
| 1324 | (if (or (char=? ch #\Z) (char=? ch #\z)) |
| 1325 | 0 |
| 1326 | (begin |
| 1327 | (cond |
| 1328 | ((char=? ch #\+) (set! positive? #t)) |
| 1329 | ((char=? ch #\-) (set! positive? #f)) |
| 1330 | (else |
| 1331 | (priv:time-error 'string->date 'bad-date-template-string |
| 1332 | (list "Invalid time zone +/-" ch)))) |
| 1333 | (let ((ch (read-char port))) |
| 1334 | (if (eof-object? ch) |
| 1335 | (priv:time-error 'string->date 'bad-date-template-string |
| 1336 | (list "Invalid time zone number" ch))) |
| 1337 | (set! offset (* (priv:char->int ch) |
| 1338 | 10 60 60))) |
| 1339 | (let ((ch (read-char port))) |
| 1340 | (if (eof-object? ch) |
| 1341 | (priv:time-error 'string->date 'bad-date-template-string |
| 1342 | (list "Invalid time zone number" ch))) |
| 1343 | (set! offset (+ offset (* (priv:char->int ch) |
| 1344 | 60 60)))) |
| 1345 | (let ((ch (read-char port))) |
| 1346 | (if (eof-object? ch) |
| 1347 | (priv:time-error 'string->date 'bad-date-template-string |
| 1348 | (list "Invalid time zone number" ch))) |
| 1349 | (set! offset (+ offset (* (priv:char->int ch) |
| 1350 | 10 60)))) |
| 1351 | (let ((ch (read-char port))) |
| 1352 | (if (eof-object? ch) |
| 1353 | (priv:time-error 'string->date 'bad-date-template-string |
| 1354 | (list "Invalid time zone number" ch))) |
| 1355 | (set! offset (+ offset (* (priv:char->int ch) |
| 1356 | 60)))) |
| 1357 | (if positive? offset (- offset))))))) |
| 1358 | |
| 1359 | ;; looking at a char, read the char string, run thru indexer, return index |
| 1360 | (define (priv:locale-reader port indexer) |
| 1361 | |
| 1362 | (define (read-char-string result) |
| 1363 | (let ((ch (peek-char port))) |
| 1364 | (if (char-alphabetic? ch) |
| 1365 | (read-char-string (cons (read-char port) result)) |
| 1366 | (list->string (reverse! result))))) |
| 1367 | |
| 1368 | (let* ((str (read-char-string '())) |
| 1369 | (index (indexer str))) |
| 1370 | (if index index (priv:time-error 'string->date |
| 1371 | 'bad-date-template-string |
| 1372 | (list "Invalid string for " indexer))))) |
| 1373 | |
| 1374 | (define (priv:make-locale-reader indexer) |
| 1375 | (lambda (port) |
| 1376 | (priv:locale-reader port indexer))) |
| 1377 | |
| 1378 | (define (priv:make-char-id-reader char) |
| 1379 | (lambda (port) |
| 1380 | (if (char=? char (read-char port)) |
| 1381 | char |
| 1382 | (priv:time-error 'string->date |
| 1383 | 'bad-date-template-string |
| 1384 | "Invalid character match.")))) |
| 1385 | |
| 1386 | ;; A List of formatted read directives. |
| 1387 | ;; Each entry is a list. |
| 1388 | ;; 1. the character directive; |
| 1389 | ;; a procedure, which takes a character as input & returns |
| 1390 | ;; 2. #t as soon as a character on the input port is acceptable |
| 1391 | ;; for input, |
| 1392 | ;; 3. a port reader procedure that knows how to read the current port |
| 1393 | ;; for a value. Its one parameter is the port. |
| 1394 | ;; 4. a action procedure, that takes the value (from 3.) and some |
| 1395 | ;; object (here, always the date) and (probably) side-effects it. |
| 1396 | ;; In some cases (e.g., ~A) the action is to do nothing |
| 1397 | |
| 1398 | (define priv:read-directives |
| 1399 | (let ((ireader4 (priv:make-integer-reader 4)) |
| 1400 | (ireader2 (priv:make-integer-reader 2)) |
| 1401 | (ireaderf (priv:make-integer-reader #f)) |
| 1402 | (eireader2 (priv:make-integer-exact-reader 2)) |
| 1403 | (eireader4 (priv:make-integer-exact-reader 4)) |
| 1404 | (locale-reader-abbr-weekday (priv:make-locale-reader |
| 1405 | priv:locale-abbr-weekday->index)) |
| 1406 | (locale-reader-long-weekday (priv:make-locale-reader |
| 1407 | priv:locale-long-weekday->index)) |
| 1408 | (locale-reader-abbr-month (priv:make-locale-reader |
| 1409 | priv:locale-abbr-month->index)) |
| 1410 | (locale-reader-long-month (priv:make-locale-reader |
| 1411 | priv:locale-long-month->index)) |
| 1412 | (char-fail (lambda (ch) #t)) |
| 1413 | (do-nothing (lambda (val object) (values)))) |
| 1414 | |
| 1415 | (list |
| 1416 | (list #\~ char-fail (priv:make-char-id-reader #\~) do-nothing) |
| 1417 | (list #\a char-alphabetic? locale-reader-abbr-weekday do-nothing) |
| 1418 | (list #\A char-alphabetic? locale-reader-long-weekday do-nothing) |
| 1419 | (list #\b char-alphabetic? locale-reader-abbr-month |
| 1420 | (lambda (val object) |
| 1421 | (set-date-month! object val))) |
| 1422 | (list #\B char-alphabetic? locale-reader-long-month |
| 1423 | (lambda (val object) |
| 1424 | (set-date-month! object val))) |
| 1425 | (list #\d char-numeric? ireader2 (lambda (val object) |
| 1426 | (set-date-day! |
| 1427 | object val))) |
| 1428 | (list #\e char-fail eireader2 (lambda (val object) |
| 1429 | (set-date-day! object val))) |
| 1430 | (list #\h char-alphabetic? locale-reader-abbr-month |
| 1431 | (lambda (val object) |
| 1432 | (set-date-month! object val))) |
| 1433 | (list #\H char-numeric? ireader2 (lambda (val object) |
| 1434 | (set-date-hour! object val))) |
| 1435 | (list #\k char-fail eireader2 (lambda (val object) |
| 1436 | (set-date-hour! object val))) |
| 1437 | (list #\m char-numeric? ireader2 (lambda (val object) |
| 1438 | (set-date-month! object val))) |
| 1439 | (list #\M char-numeric? ireader2 (lambda (val object) |
| 1440 | (set-date-minute! |
| 1441 | object val))) |
| 1442 | (list #\S char-numeric? ireader2 (lambda (val object) |
| 1443 | (set-date-second! object val))) |
| 1444 | (list #\y char-fail eireader2 |
| 1445 | (lambda (val object) |
| 1446 | (set-date-year! object (priv:natural-year val)))) |
| 1447 | (list #\Y char-numeric? ireader4 (lambda (val object) |
| 1448 | (set-date-year! object val))) |
| 1449 | (list #\z (lambda (c) |
| 1450 | (or (char=? c #\Z) |
| 1451 | (char=? c #\z) |
| 1452 | (char=? c #\+) |
| 1453 | (char=? c #\-))) |
| 1454 | priv:zone-reader (lambda (val object) |
| 1455 | (set-date-zone-offset! object val)))))) |
| 1456 | |
| 1457 | (define (priv:string->date date index format-string str-len port template-string) |
| 1458 | (define (skip-until port skipper) |
| 1459 | (let ((ch (peek-char port))) |
| 1460 | (if (eof-object? port) |
| 1461 | (priv:time-error 'string->date 'bad-date-format-string template-string) |
| 1462 | (if (not (skipper ch)) |
| 1463 | (begin (read-char port) (skip-until port skipper)))))) |
| 1464 | (if (>= index str-len) |
| 1465 | (begin |
| 1466 | (values)) |
| 1467 | (let ((current-char (string-ref format-string index))) |
| 1468 | (if (not (char=? current-char #\~)) |
| 1469 | (let ((port-char (read-char port))) |
| 1470 | (if (or (eof-object? port-char) |
| 1471 | (not (char=? current-char port-char))) |
| 1472 | (priv:time-error 'string->date |
| 1473 | 'bad-date-format-string template-string)) |
| 1474 | (priv:string->date date |
| 1475 | (+ index 1) |
| 1476 | format-string |
| 1477 | str-len |
| 1478 | port |
| 1479 | template-string)) |
| 1480 | ;; otherwise, it's an escape, we hope |
| 1481 | (if (> (+ index 1) str-len) |
| 1482 | (priv:time-error 'string->date |
| 1483 | 'bad-date-format-string template-string) |
| 1484 | (let* ((format-char (string-ref format-string (+ index 1))) |
| 1485 | (format-info (assoc format-char priv:read-directives))) |
| 1486 | (if (not format-info) |
| 1487 | (priv:time-error 'string->date |
| 1488 | 'bad-date-format-string template-string) |
| 1489 | (begin |
| 1490 | (let ((skipper (cadr format-info)) |
| 1491 | (reader (caddr format-info)) |
| 1492 | (actor (cadddr format-info))) |
| 1493 | (skip-until port skipper) |
| 1494 | (let ((val (reader port))) |
| 1495 | (if (eof-object? val) |
| 1496 | (priv:time-error 'string->date |
| 1497 | 'bad-date-format-string |
| 1498 | template-string) |
| 1499 | (actor val date))) |
| 1500 | (priv:string->date date |
| 1501 | (+ index 2) |
| 1502 | format-string |
| 1503 | str-len |
| 1504 | port |
| 1505 | template-string)))))))))) |
| 1506 | |
| 1507 | (define (string->date input-string template-string) |
| 1508 | (define (priv:date-ok? date) |
| 1509 | (and (date-nanosecond date) |
| 1510 | (date-second date) |
| 1511 | (date-minute date) |
| 1512 | (date-hour date) |
| 1513 | (date-day date) |
| 1514 | (date-month date) |
| 1515 | (date-year date) |
| 1516 | (date-zone-offset date))) |
| 1517 | (let ((newdate (make-date 0 0 0 0 #f #f #f #f))) |
| 1518 | (priv:string->date newdate |
| 1519 | 0 |
| 1520 | template-string |
| 1521 | (string-length template-string) |
| 1522 | (open-input-string input-string) |
| 1523 | template-string) |
| 1524 | (if (not (date-zone-offset newdate)) |
| 1525 | (begin |
| 1526 | ;; this is necessary to get DST right -- as far as we can |
| 1527 | ;; get it right (think of the double/missing hour in the |
| 1528 | ;; night when we are switching between normal time and DST). |
| 1529 | (set-date-zone-offset! newdate |
| 1530 | (priv:local-tz-offset |
| 1531 | (make-time time-utc 0 0))) |
| 1532 | (set-date-zone-offset! newdate |
| 1533 | (priv:local-tz-offset |
| 1534 | (date->time-utc newdate))))) |
| 1535 | (if (priv:date-ok? newdate) |
| 1536 | newdate |
| 1537 | (priv:time-error |
| 1538 | 'string->date |
| 1539 | 'bad-date-format-string |
| 1540 | (list "Incomplete date read. " newdate template-string))))) |
| 1541 | |
| 1542 | ;;; srfi-19.scm ends here |