1 /* Parse a time duration and return a seconds count
2 Copyright (C) 2008-2017 Free Software Foundation, Inc.
3 Written by Bruce Korb <bkorb@gnu.org>, 2008.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program 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
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
21 #include "parse-duration.h"
36 #define cch_t char const
49 #define SEC_PER_MIN 60
50 #define SEC_PER_HR (SEC_PER_MIN * 60)
51 #define SEC_PER_DAY (SEC_PER_HR * 24)
52 #define SEC_PER_WEEK (SEC_PER_DAY * 7)
53 #define SEC_PER_MONTH (SEC_PER_DAY * 30)
54 #define SEC_PER_YEAR (SEC_PER_DAY * 365)
57 #define MAX_DURATION TYPE_MAXIMUM(time_t)
59 /* Wrapper around strtoul that does not require a cast. */
61 str_const_to_ul (cch_t
* str
, cch_t
** ppz
, int base
)
63 return strtoul (str
, (char **)ppz
, base
);
66 /* Wrapper around strtol that does not require a cast. */
68 str_const_to_l (cch_t
* str
, cch_t
** ppz
, int base
)
70 return strtol (str
, (char **)ppz
, base
);
73 /* Returns BASE + VAL * SCALE, interpreting BASE = BAD_TIME
74 with errno set as an error situation, and returning BAD_TIME
75 with errno set in an error situation. */
77 scale_n_add (time_t base
, time_t val
, int scale
)
86 if (val
> MAX_DURATION
/ scale
)
93 if (base
> MAX_DURATION
- val
)
102 /* After a number HH has been parsed, parse subsequent :MM or :MM:SS. */
104 parse_hr_min_sec (time_t start
, cch_t
* pz
)
110 /* For as long as our scanner pointer points to a colon *AND*
111 we've not looped before, then keep looping. (two iterations max) */
112 while ((*pz
== ':') && (lpct
++ <= 1))
114 unsigned long v
= str_const_to_ul (pz
+1, &pz
, 10);
119 start
= scale_n_add (v
, start
, 60);
125 /* allow for trailing spaces */
126 while (isspace ((unsigned char)*pz
))
137 /* Parses a value and returns BASE + value * SCALE, interpreting
138 BASE = BAD_TIME with errno set as an error situation, and returning
139 BAD_TIME with errno set in an error situation. */
141 parse_scaled_value (time_t base
, cch_t
** ppz
, cch_t
* endp
, int scale
)
146 if (base
== BAD_TIME
)
150 val
= str_const_to_ul (pz
, &pz
, 10);
153 while (isspace ((unsigned char)*pz
))
162 return scale_n_add (base
, val
, scale
);
165 /* Parses the syntax YEAR-MONTH-DAY.
166 PS points into the string, after "YEAR", before "-MONTH-DAY". */
168 parse_year_month_day (cch_t
* pz
, cch_t
* ps
)
172 res
= parse_scaled_value (0, &pz
, ps
, SEC_PER_YEAR
);
174 pz
++; /* over the first '-' */
175 ps
= strchr (pz
, '-');
181 res
= parse_scaled_value (res
, &pz
, ps
, SEC_PER_MONTH
);
183 pz
++; /* over the second '-' */
184 ps
= pz
+ strlen (pz
);
185 return parse_scaled_value (res
, &pz
, ps
, SEC_PER_DAY
);
188 /* Parses the syntax YYYYMMDD. */
190 parse_yearmonthday (cch_t
* in_pz
)
196 if (strlen (in_pz
) != 8)
202 memcpy (buf
, in_pz
, 4);
205 res
= parse_scaled_value (0, &pz
, buf
+ 4, SEC_PER_YEAR
);
207 memcpy (buf
, in_pz
+ 4, 2);
210 res
= parse_scaled_value (res
, &pz
, buf
+ 2, SEC_PER_MONTH
);
212 memcpy (buf
, in_pz
+ 6, 2);
215 return parse_scaled_value (res
, &pz
, buf
+ 2, SEC_PER_DAY
);
218 /* Parses the syntax yy Y mm M ww W dd D. */
220 parse_YMWD (cch_t
* pz
)
223 cch_t
* ps
= strchr (pz
, 'Y');
226 res
= parse_scaled_value (0, &pz
, ps
, SEC_PER_YEAR
);
230 ps
= strchr (pz
, 'M');
233 res
= parse_scaled_value (res
, &pz
, ps
, SEC_PER_MONTH
);
237 ps
= strchr (pz
, 'W');
240 res
= parse_scaled_value (res
, &pz
, ps
, SEC_PER_WEEK
);
244 ps
= strchr (pz
, 'D');
247 res
= parse_scaled_value (res
, &pz
, ps
, SEC_PER_DAY
);
251 while (isspace ((unsigned char)*pz
))
262 /* Parses the syntax HH:MM:SS.
263 PS points into the string, after "HH", before ":MM:SS". */
265 parse_hour_minute_second (cch_t
* pz
, cch_t
* ps
)
269 res
= parse_scaled_value (0, &pz
, ps
, SEC_PER_HR
);
272 ps
= strchr (pz
, ':');
279 res
= parse_scaled_value (res
, &pz
, ps
, SEC_PER_MIN
);
282 ps
= pz
+ strlen (pz
);
283 return parse_scaled_value (res
, &pz
, ps
, 1);
286 /* Parses the syntax HHMMSS. */
288 parse_hourminutesecond (cch_t
* in_pz
)
294 if (strlen (in_pz
) != 6)
300 memcpy (buf
, in_pz
, 2);
303 res
= parse_scaled_value (0, &pz
, buf
+ 2, SEC_PER_HR
);
305 memcpy (buf
, in_pz
+ 2, 2);
308 res
= parse_scaled_value (res
, &pz
, buf
+ 2, SEC_PER_MIN
);
310 memcpy (buf
, in_pz
+ 4, 2);
313 return parse_scaled_value (res
, &pz
, buf
+ 2, 1);
316 /* Parses the syntax hh H mm M ss S. */
318 parse_HMS (cch_t
* pz
)
321 cch_t
* ps
= strchr (pz
, 'H');
324 res
= parse_scaled_value (0, &pz
, ps
, SEC_PER_HR
);
328 ps
= strchr (pz
, 'M');
331 res
= parse_scaled_value (res
, &pz
, ps
, SEC_PER_MIN
);
335 ps
= strchr (pz
, 'S');
338 res
= parse_scaled_value (res
, &pz
, ps
, 1);
342 while (isspace ((unsigned char)*pz
))
353 /* Parses a time (hours, minutes, seconds) specification in either syntax. */
355 parse_time (cch_t
* pz
)
363 ps
= strchr (pz
, ':');
366 res
= parse_hour_minute_second (pz
, ps
);
370 * Try for a 'H', 'M' or 'S' suffix
372 else if (ps
= strpbrk (pz
, "HMS"),
375 /* Its a YYYYMMDD format: */
376 res
= parse_hourminutesecond (pz
);
380 res
= parse_HMS (pz
);
385 /* Returns a substring of the given string, with spaces at the beginning and at
386 the end destructively removed, per SNOBOL. */
390 /* trim leading white space */
391 while (isspace ((unsigned char)*pz
))
394 /* trim trailing white space */
396 char * pe
= pz
+ strlen (pz
);
397 while ((pe
> pz
) && isspace ((unsigned char)pe
[-1]))
406 * Parse the year/months/days of a time period
409 parse_period (cch_t
* in_pz
)
413 char * pz
= strdup (in_pz
);
423 pT
= strchr (pz
, 'T');
434 ps
= strchr (pz
, '-');
437 res
= parse_year_month_day (pz
, ps
);
441 * Try for a 'Y', 'M' or 'D' suffix
443 else if (ps
= strpbrk (pz
, "YMWD"),
446 /* Its a YYYYMMDD format: */
447 res
= parse_yearmonthday (pz
);
451 res
= parse_YMWD (pz
);
453 if ((errno
== 0) && (pT
!= NULL
))
455 time_t val
= parse_time (pT
);
456 res
= scale_n_add (res
, val
, 1);
464 parse_non_iso8601 (cch_t
* pz
)
466 whats_done_t whatd_we_do
= NOTHING_IS_DONE
;
474 val
= str_const_to_l (pz
, &pz
, 10);
478 /* IF we find a colon, then we're going to have a seconds value.
479 We will not loop here any more. We cannot already have parsed
480 a minute value and if we've parsed an hour value, then the result
481 value has to be less than an hour. */
484 if (whatd_we_do
>= MINUTE_IS_DONE
)
487 val
= parse_hr_min_sec (val
, pz
);
489 if ((whatd_we_do
== HOUR_IS_DONE
) && (val
>= SEC_PER_HR
))
492 return scale_n_add (res
, val
, 1);
498 /* Skip over white space following the number we just parsed. */
499 while (isspace ((unsigned char)*pz
))
504 default: goto bad_time
;
506 return scale_n_add (res
, val
, 1);
509 if (whatd_we_do
>= YEAR_IS_DONE
)
512 whatd_we_do
= YEAR_IS_DONE
;
516 if (whatd_we_do
>= MONTH_IS_DONE
)
518 mult
= SEC_PER_MONTH
;
519 whatd_we_do
= MONTH_IS_DONE
;
523 if (whatd_we_do
>= WEEK_IS_DONE
)
526 whatd_we_do
= WEEK_IS_DONE
;
530 if (whatd_we_do
>= DAY_IS_DONE
)
533 whatd_we_do
= DAY_IS_DONE
;
537 if (whatd_we_do
>= HOUR_IS_DONE
)
540 whatd_we_do
= HOUR_IS_DONE
;
544 if (whatd_we_do
>= MINUTE_IS_DONE
)
547 whatd_we_do
= MINUTE_IS_DONE
;
552 whatd_we_do
= SECOND_IS_DONE
;
556 res
= scale_n_add (res
, val
, mult
);
559 while (isspace ((unsigned char)*pz
))
564 if (! isdigit ((unsigned char)*pz
))
568 } while (whatd_we_do
< SECOND_IS_DONE
);
576 parse_duration (char const * pz
)
578 while (isspace ((unsigned char)*pz
))
584 return parse_period (pz
+ 1);
587 return parse_time (pz
+ 1);
590 if (isdigit ((unsigned char)*pz
))
591 return parse_non_iso8601 (pz
);
601 * c-file-style: "gnu"
602 * indent-tabs-mode: nil
604 * end of parse-duration.c */