diff options
Diffstat (limited to 'tdate_parse.c')
-rw-r--r-- | tdate_parse.c | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/tdate_parse.c b/tdate_parse.c new file mode 100644 index 0000000..ac9d2ca --- /dev/null +++ b/tdate_parse.c @@ -0,0 +1,327 @@ +/* tdate_parse - parse string dates into internal form, stripped-down version +** +** Copyright © 1995 by Jef Poskanzer <jef@mail.acme.com>. +** All rights reserved. +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions +** are met: +** 1. Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** 2. Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in the +** documentation and/or other materials provided with the distribution. +** +** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +** ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +** SUCH DAMAGE. +*/ + +/* This is a stripped-down version of date_parse.c, available at +** http://www.acme.com/software/date_parse/ +*/ + +#include <sys/types.h> + +#include <ctype.h> +#ifdef HAVE_MEMORY_H +#include <memory.h> +#endif +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> + +#include "tdate_parse.h" + + +struct strlong { + char* s; + long l; + }; + + +static void +pound_case( char* str ) + { + for ( ; *str != '\0'; ++str ) + { + if ( isupper( (int) *str ) ) + *str = tolower( (int) *str ); + } + } + +static int +strlong_compare( v1, v2 ) + char* v1; + char* v2; + { + return strcmp( ((struct strlong*) v1)->s, ((struct strlong*) v2)->s ); + } + + +static int +strlong_search( char* str, struct strlong* tab, int n, long* lP ) + { + int i, h, l, r; + + l = 0; + h = n - 1; + for (;;) + { + i = ( h + l ) / 2; + r = strcmp( str, tab[i].s ); + if ( r < 0 ) + h = i - 1; + else if ( r > 0 ) + l = i + 1; + else + { + *lP = tab[i].l; + return 1; + } + if ( h < l ) + return 0; + } + } + + +static int +scan_wday( char* str_wday, long* tm_wdayP ) + { + static struct strlong wday_tab[] = { + { "sun", 0 }, { "sunday", 0 }, + { "mon", 1 }, { "monday", 1 }, + { "tue", 2 }, { "tuesday", 2 }, + { "wed", 3 }, { "wednesday", 3 }, + { "thu", 4 }, { "thursday", 4 }, + { "fri", 5 }, { "friday", 5 }, + { "sat", 6 }, { "saturday", 6 }, + }; + static int sorted = 0; + + if ( ! sorted ) + { + (void) qsort( + wday_tab, sizeof(wday_tab)/sizeof(struct strlong), + sizeof(struct strlong), strlong_compare ); + sorted = 1; + } + pound_case( str_wday ); + return strlong_search( + str_wday, wday_tab, sizeof(wday_tab)/sizeof(struct strlong), tm_wdayP ); + } + + +static int +scan_mon( char* str_mon, long* tm_monP ) + { + static struct strlong mon_tab[] = { + { "jan", 0 }, { "january", 0 }, + { "feb", 1 }, { "february", 1 }, + { "mar", 2 }, { "march", 2 }, + { "apr", 3 }, { "april", 3 }, + { "may", 4 }, + { "jun", 5 }, { "june", 5 }, + { "jul", 6 }, { "july", 6 }, + { "aug", 7 }, { "august", 7 }, + { "sep", 8 }, { "september", 8 }, + { "oct", 9 }, { "october", 9 }, + { "nov", 10 }, { "november", 10 }, + { "dec", 11 }, { "december", 11 }, + }; + static int sorted = 0; + + if ( ! sorted ) + { + (void) qsort( + mon_tab, sizeof(mon_tab)/sizeof(struct strlong), + sizeof(struct strlong), strlong_compare ); + sorted = 1; + } + pound_case( str_mon ); + return strlong_search( + str_mon, mon_tab, sizeof(mon_tab)/sizeof(struct strlong), tm_monP ); + } + + +static int +is_leap( int year ) + { + return year % 400? ( year % 100 ? ( year % 4 ? 0 : 1 ) : 0 ) : 1; + } + + +/* Basically the same as mktime(). */ +static time_t +tm_to_time( struct tm* tmP ) + { + time_t t; + static int monthtab[12] = { + 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; + + /* Years since epoch, converted to days. */ + t = ( tmP->tm_year - 70 ) * 365; + /* Leap days for previous years. */ + t += ( tmP->tm_year - 69 ) / 4; + /* Days for the beginning of this month. */ + t += monthtab[tmP->tm_mon]; + /* Leap day for this year. */ + if ( tmP->tm_mon >= 2 && is_leap( tmP->tm_year + 1900 ) ) + ++t; + /* Days since the beginning of this month. */ + t += tmP->tm_mday - 1; /* 1-based field */ + /* Hours, minutes, and seconds. */ + t = t * 24 + tmP->tm_hour; + t = t * 60 + tmP->tm_min; + t = t * 60 + tmP->tm_sec; + + return t; + } + + +time_t +tdate_parse( char* str ) + { + struct tm tm; + char* cp; + char str_mon[500], str_wday[500]; + int tm_sec, tm_min, tm_hour, tm_mday, tm_year; + long tm_mon, tm_wday; + time_t t; + + /* Initialize. */ + (void) memset( (char*) &tm, 0, sizeof(struct tm) ); + + /* Skip initial whitespace ourselves - sscanf is clumsy at this. */ + for ( cp = str; *cp == ' ' || *cp == '\t'; ++cp ) + continue; + + /* And do the sscanfs. WARNING: you can add more formats here, + ** but be careful! You can easily screw up the parsing of existing + ** formats when you add new ones. The order is important. + */ + + /* DD-mth-YY HH:MM:SS GMT */ + if ( sscanf( cp, "%d-%400[a-zA-Z]-%d %d:%d:%d GMT", + &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, + &tm_sec ) == 6 && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_mday = tm_mday; + tm.tm_mon = tm_mon; + tm.tm_year = tm_year; + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + } + + /* DD mth YY HH:MM:SS GMT */ + else if ( sscanf( cp, "%d %400[a-zA-Z] %d %d:%d:%d GMT", + &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, + &tm_sec) == 6 && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_mday = tm_mday; + tm.tm_mon = tm_mon; + tm.tm_year = tm_year; + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + } + + /* HH:MM:SS GMT DD-mth-YY */ + else if ( sscanf( cp, "%d:%d:%d GMT %d-%400[a-zA-Z]-%d", + &tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon, + &tm_year ) == 6 && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + tm.tm_mday = tm_mday; + tm.tm_mon = tm_mon; + tm.tm_year = tm_year; + } + + /* HH:MM:SS GMT DD mth YY */ + else if ( sscanf( cp, "%d:%d:%d GMT %d %400[a-zA-Z] %d", + &tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon, + &tm_year ) == 6 && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + tm.tm_mday = tm_mday; + tm.tm_mon = tm_mon; + tm.tm_year = tm_year; + } + + /* wdy, DD-mth-YY HH:MM:SS GMT */ + else if ( sscanf( cp, "%400[a-zA-Z], %d-%400[a-zA-Z]-%d %d:%d:%d GMT", + str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, + &tm_sec ) == 7 && + scan_wday( str_wday, &tm_wday ) && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_wday = tm_wday; + tm.tm_mday = tm_mday; + tm.tm_mon = tm_mon; + tm.tm_year = tm_year; + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + } + + /* wdy, DD mth YY HH:MM:SS GMT */ + else if ( sscanf( cp, "%400[a-zA-Z], %d %400[a-zA-Z] %d %d:%d:%d GMT", + str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, + &tm_sec ) == 7 && + scan_wday( str_wday, &tm_wday ) && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_wday = tm_wday; + tm.tm_mday = tm_mday; + tm.tm_mon = tm_mon; + tm.tm_year = tm_year; + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + } + + /* wdy mth DD HH:MM:SS GMT YY */ + else if ( sscanf( cp, "%400[a-zA-Z] %400[a-zA-Z] %d %d:%d:%d GMT %d", + str_wday, str_mon, &tm_mday, &tm_hour, &tm_min, &tm_sec, + &tm_year ) == 7 && + scan_wday( str_wday, &tm_wday ) && + scan_mon( str_mon, &tm_mon ) ) + { + tm.tm_wday = tm_wday; + tm.tm_mon = tm_mon; + tm.tm_mday = tm_mday; + tm.tm_hour = tm_hour; + tm.tm_min = tm_min; + tm.tm_sec = tm_sec; + tm.tm_year = tm_year; + } + else + return (time_t) -1; + + if ( tm.tm_year > 1900 ) + tm.tm_year -= 1900; + else if ( tm.tm_year < 70 ) + tm.tm_year += 100; + + t = tm_to_time( &tm ); + + return t; + } |