notmuch/parse-time-string/parse-time-string.h
David Bremner f7130468d2 Import notmuch_0.28.2.orig.tar.gz
[dgit import orig notmuch_0.28.2.orig.tar.gz]
2019-02-17 07:30:33 -04:00

102 lines
3.7 KiB
C

/*
* parse time string - user friendly date and time parser
* Copyright © 2012 Jani Nikula
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
* Author: Jani Nikula <jani@nikula.org>
*/
#ifndef PARSE_TIME_STRING_H
#define PARSE_TIME_STRING_H
#ifdef __cplusplus
extern "C" {
#endif
#include <time.h>
/* return values for parse_time_string() */
enum {
PARSE_TIME_OK = 0,
PARSE_TIME_ERR, /* unspecified error */
PARSE_TIME_ERR_LIB, /* library call failed */
PARSE_TIME_ERR_ALREADYSET, /* attempt to set unit twice */
PARSE_TIME_ERR_FORMAT, /* generic date/time format error */
PARSE_TIME_ERR_DATEFORMAT, /* date format error */
PARSE_TIME_ERR_TIMEFORMAT, /* time format error */
PARSE_TIME_ERR_INVALIDDATE, /* date value error */
PARSE_TIME_ERR_INVALIDTIME, /* time value error */
PARSE_TIME_ERR_KEYWORD, /* unknown keyword */
};
/* round values for parse_time_string() */
enum {
PARSE_TIME_ROUND_DOWN = -1,
PARSE_TIME_NO_ROUND = 0,
PARSE_TIME_ROUND_UP = 1,
PARSE_TIME_ROUND_UP_INCLUSIVE = 2,
};
/**
* parse_time_string() - user friendly date and time parser
* @s: string to parse
* @t: pointer to time_t to store parsed time in
* @ref: pointer to time_t containing reference date/time, or NULL
* @round: PARSE_TIME_NO_ROUND, PARSE_TIME_ROUND_DOWN, or
* PARSE_TIME_ROUND_UP
*
* Parse a date/time string 's' and store the parsed date/time result
* in 't'.
*
* A reference date/time is used for determining the "date/time units"
* (roughly equivalent to struct tm members) not specified by 's'. If
* 'ref' is non-NULL, it must contain a pointer to a time_t to be used
* as reference date/time. Otherwise, the current time is used.
*
* If 's' does not specify a full date/time, the 'round' parameter
* specifies if and how the result should be rounded as follows:
*
* PARSE_TIME_NO_ROUND: All date/time units that are not specified
* by 's' are set to the corresponding unit derived from the
* reference date/time.
*
* PARSE_TIME_ROUND_DOWN: All date/time units that are more accurate
* than the most accurate unit specified by 's' are set to the
* smallest valid value for that unit. Rest of the unspecified units
* are set as in PARSE_TIME_NO_ROUND.
*
* PARSE_TIME_ROUND_UP: All date/time units that are more accurate
* than the most accurate unit specified by 's' are set to the
* smallest valid value for that unit. The most accurate unit
* specified by 's' is incremented by one (and this is rolled over
* to the less accurate units as necessary), unless the most
* accurate unit is seconds. Rest of the unspecified units are set
* as in PARSE_TIME_NO_ROUND.
*
* PARSE_TIME_ROUND_UP_INCLUSIVE: Same as PARSE_TIME_ROUND_UP, minus
* one second, unless the most accurate unit specified by 's' is
* seconds. This is useful for callers that require a value for
* inclusive comparison of the result.
*
* Return 0 (PARSE_TIME_OK) for successfully parsed date/time, or one
* of PARSE_TIME_ERR_* on error. 't' is not modified on error.
*/
int parse_time_string (const char *s, time_t *t, const time_t *ref, int round);
#ifdef __cplusplus
}
#endif
#endif /* PARSE_TIME_STRING_H */