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Diffstat (limited to 'lib/parsedate.c')
| -rw-r--r-- | lib/parsedate.c | 580 |
1 files changed, 580 insertions, 0 deletions
diff --git a/lib/parsedate.c b/lib/parsedate.c new file mode 100644 index 000000000..b6079bc8f --- /dev/null +++ b/lib/parsedate.c @@ -0,0 +1,580 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at http://curl.haxx.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ***************************************************************************/ +/* + A brief summary of the date string formats this parser groks: + + RFC 2616 3.3.1 + + Sun, 06 Nov 1994 08:49:37 GMT ; RFC 822, updated by RFC 1123 + Sunday, 06-Nov-94 08:49:37 GMT ; RFC 850, obsoleted by RFC 1036 + Sun Nov 6 08:49:37 1994 ; ANSI C's asctime() format + + we support dates without week day name: + + 06 Nov 1994 08:49:37 GMT + 06-Nov-94 08:49:37 GMT + Nov 6 08:49:37 1994 + + without the time zone: + + 06 Nov 1994 08:49:37 + 06-Nov-94 08:49:37 + + weird order: + + 1994 Nov 6 08:49:37 (GNU date fails) + GMT 08:49:37 06-Nov-94 Sunday + 94 6 Nov 08:49:37 (GNU date fails) + + time left out: + + 1994 Nov 6 + 06-Nov-94 + Sun Nov 6 94 + + unusual separators: + + 1994.Nov.6 + Sun/Nov/6/94/GMT + + commonly used time zone names: + + Sun, 06 Nov 1994 08:49:37 CET + 06 Nov 1994 08:49:37 EST + + time zones specified using RFC822 style: + + Sun, 12 Sep 2004 15:05:58 -0700 + Sat, 11 Sep 2004 21:32:11 +0200 + + compact numerical date strings: + + 20040912 15:05:58 -0700 + 20040911 +0200 + +*/ + +#include "setup.h" + +#ifdef HAVE_LIMITS_H +#include <limits.h> +#endif + +#include <curl/curl.h> +#include "rawstr.h" +#include "warnless.h" +#include "parsedate.h" + +const char * const Curl_wkday[] = +{"Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"}; +static const char * const weekday[] = +{ "Monday", "Tuesday", "Wednesday", "Thursday", + "Friday", "Saturday", "Sunday" }; +const char * const Curl_month[]= +{ "Jan", "Feb", "Mar", "Apr", "May", "Jun", + "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; + +struct tzinfo { + char name[5]; + int offset; /* +/- in minutes */ +}; + +/* + * parsedate() + * + * Returns: + * + * PARSEDATE_OK - a fine conversion + * PARSEDATE_FAIL - failed to convert + * PARSEDATE_LATER - time overflow at the far end of time_t + * PARSEDATE_SOONER - time underflow at the low end of time_t + */ + +static int parsedate(const char *date, time_t *output); + +#define PARSEDATE_OK 0 +#define PARSEDATE_FAIL -1 +#define PARSEDATE_LATER 1 +#define PARSEDATE_SOONER 2 + +/* Here's a bunch of frequently used time zone names. These were supported + by the old getdate parser. */ +#define tDAYZONE -60 /* offset for daylight savings time */ +static const struct tzinfo tz[]= { + {"GMT", 0}, /* Greenwich Mean */ + {"UTC", 0}, /* Universal (Coordinated) */ + {"WET", 0}, /* Western European */ + {"BST", 0 tDAYZONE}, /* British Summer */ + {"WAT", 60}, /* West Africa */ + {"AST", 240}, /* Atlantic Standard */ + {"ADT", 240 tDAYZONE}, /* Atlantic Daylight */ + {"EST", 300}, /* Eastern Standard */ + {"EDT", 300 tDAYZONE}, /* Eastern Daylight */ + {"CST", 360}, /* Central Standard */ + {"CDT", 360 tDAYZONE}, /* Central Daylight */ + {"MST", 420}, /* Mountain Standard */ + {"MDT", 420 tDAYZONE}, /* Mountain Daylight */ + {"PST", 480}, /* Pacific Standard */ + {"PDT", 480 tDAYZONE}, /* Pacific Daylight */ + {"YST", 540}, /* Yukon Standard */ + {"YDT", 540 tDAYZONE}, /* Yukon Daylight */ + {"HST", 600}, /* Hawaii Standard */ + {"HDT", 600 tDAYZONE}, /* Hawaii Daylight */ + {"CAT", 600}, /* Central Alaska */ + {"AHST", 600}, /* Alaska-Hawaii Standard */ + {"NT", 660}, /* Nome */ + {"IDLW", 720}, /* International Date Line West */ + {"CET", -60}, /* Central European */ + {"MET", -60}, /* Middle European */ + {"MEWT", -60}, /* Middle European Winter */ + {"MEST", -60 tDAYZONE}, /* Middle European Summer */ + {"CEST", -60 tDAYZONE}, /* Central European Summer */ + {"MESZ", -60 tDAYZONE}, /* Middle European Summer */ + {"FWT", -60}, /* French Winter */ + {"FST", -60 tDAYZONE}, /* French Summer */ + {"EET", -120}, /* Eastern Europe, USSR Zone 1 */ + {"WAST", -420}, /* West Australian Standard */ + {"WADT", -420 tDAYZONE}, /* West Australian Daylight */ + {"CCT", -480}, /* China Coast, USSR Zone 7 */ + {"JST", -540}, /* Japan Standard, USSR Zone 8 */ + {"EAST", -600}, /* Eastern Australian Standard */ + {"EADT", -600 tDAYZONE}, /* Eastern Australian Daylight */ + {"GST", -600}, /* Guam Standard, USSR Zone 9 */ + {"NZT", -720}, /* New Zealand */ + {"NZST", -720}, /* New Zealand Standard */ + {"NZDT", -720 tDAYZONE}, /* New Zealand Daylight */ + {"IDLE", -720}, /* International Date Line East */ + /* Next up: Military timezone names. RFC822 allowed these, but (as noted in + RFC 1123) had their signs wrong. Here we use the correct signs to match + actual military usage. + */ + {"A", +1 * 60}, /* Alpha */ + {"B", +2 * 60}, /* Bravo */ + {"C", +3 * 60}, /* Charlie */ + {"D", +4 * 60}, /* Delta */ + {"E", +5 * 60}, /* Echo */ + {"F", +6 * 60}, /* Foxtrot */ + {"G", +7 * 60}, /* Golf */ + {"H", +8 * 60}, /* Hotel */ + {"I", +9 * 60}, /* India */ + /* "J", Juliet is not used as a timezone, to indicate the observer's local + time */ + {"K", +10 * 60}, /* Kilo */ + {"L", +11 * 60}, /* Lima */ + {"M", +12 * 60}, /* Mike */ + {"N", -1 * 60}, /* November */ + {"O", -2 * 60}, /* Oscar */ + {"P", -3 * 60}, /* Papa */ + {"Q", -4 * 60}, /* Quebec */ + {"R", -5 * 60}, /* Romeo */ + {"S", -6 * 60}, /* Sierra */ + {"T", -7 * 60}, /* Tango */ + {"U", -8 * 60}, /* Uniform */ + {"V", -9 * 60}, /* Victor */ + {"W", -10 * 60}, /* Whiskey */ + {"X", -11 * 60}, /* X-ray */ + {"Y", -12 * 60}, /* Yankee */ + {"Z", 0}, /* Zulu, zero meridian, a.k.a. UTC */ +}; + +/* returns: + -1 no day + 0 monday - 6 sunday +*/ + +static int checkday(const char *check, size_t len) +{ + int i; + const char * const *what; + bool found= FALSE; + if(len > 3) + what = &weekday[0]; + else + what = &Curl_wkday[0]; + for(i=0; i<7; i++) { + if(Curl_raw_equal(check, what[0])) { + found=TRUE; + break; + } + what++; + } + return found?i:-1; +} + +static int checkmonth(const char *check) +{ + int i; + const char * const *what; + bool found= FALSE; + + what = &Curl_month[0]; + for(i=0; i<12; i++) { + if(Curl_raw_equal(check, what[0])) { + found=TRUE; + break; + } + what++; + } + return found?i:-1; /* return the offset or -1, no real offset is -1 */ +} + +/* return the time zone offset between GMT and the input one, in number + of seconds or -1 if the timezone wasn't found/legal */ + +static int checktz(const char *check) +{ + unsigned int i; + const struct tzinfo *what; + bool found= FALSE; + + what = tz; + for(i=0; i< sizeof(tz)/sizeof(tz[0]); i++) { + if(Curl_raw_equal(check, what->name)) { + found=TRUE; + break; + } + what++; + } + return found?what->offset*60:-1; +} + +static void skip(const char **date) +{ + /* skip everything that aren't letters or digits */ + while(**date && !ISALNUM(**date)) + (*date)++; +} + +enum assume { + DATE_MDAY, + DATE_YEAR, + DATE_TIME +}; + +/* this is a clone of 'struct tm' but with all fields we don't need or use + cut out */ +struct my_tm { + int tm_sec; + int tm_min; + int tm_hour; + int tm_mday; + int tm_mon; + int tm_year; +}; + +/* struct tm to time since epoch in GMT time zone. + * This is similar to the standard mktime function but for GMT only, and + * doesn't suffer from the various bugs and portability problems that + * some systems' implementations have. + */ +static time_t my_timegm(struct my_tm *tm) +{ + static const int month_days_cumulative [12] = + { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; + int month, year, leap_days; + + if(tm->tm_year < 70) + /* we don't support years before 1970 as they will cause this function + to return a negative value */ + return -1; + + year = tm->tm_year + 1900; + month = tm->tm_mon; + if(month < 0) { + year += (11 - month) / 12; + month = 11 - (11 - month) % 12; + } + else if(month >= 12) { + year -= month / 12; + month = month % 12; + } + + leap_days = year - (tm->tm_mon <= 1); + leap_days = ((leap_days / 4) - (leap_days / 100) + (leap_days / 400) + - (1969 / 4) + (1969 / 100) - (1969 / 400)); + + return ((((time_t) (year - 1970) * 365 + + leap_days + month_days_cumulative [month] + tm->tm_mday - 1) * 24 + + tm->tm_hour) * 60 + tm->tm_min) * 60 + tm->tm_sec; +} + +/* + * parsedate() + * + * Returns: + * + * PARSEDATE_OK - a fine conversion + * PARSEDATE_FAIL - failed to convert + * PARSEDATE_LATER - time overflow at the far end of time_t + * PARSEDATE_SOONER - time underflow at the low end of time_t + */ + +static int parsedate(const char *date, time_t *output) +{ + time_t t = 0; + int wdaynum=-1; /* day of the week number, 0-6 (mon-sun) */ + int monnum=-1; /* month of the year number, 0-11 */ + int mdaynum=-1; /* day of month, 1 - 31 */ + int hournum=-1; + int minnum=-1; + int secnum=-1; + int yearnum=-1; + int tzoff=-1; + struct my_tm tm; + enum assume dignext = DATE_MDAY; + const char *indate = date; /* save the original pointer */ + int part = 0; /* max 6 parts */ + + while(*date && (part < 6)) { + bool found=FALSE; + + skip(&date); + + if(ISALPHA(*date)) { + /* a name coming up */ + char buf[32]=""; + size_t len; + sscanf(date, "%31[ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz]", + buf); + len = strlen(buf); + + if(wdaynum == -1) { + wdaynum = checkday(buf, len); + if(wdaynum != -1) + found = TRUE; + } + if(!found && (monnum == -1)) { + monnum = checkmonth(buf); + if(monnum != -1) + found = TRUE; + } + + if(!found && (tzoff == -1)) { + /* this just must be a time zone string */ + tzoff = checktz(buf); + if(tzoff != -1) + found = TRUE; + } + + if(!found) + return PARSEDATE_FAIL; /* bad string */ + + date += len; + } + else if(ISDIGIT(*date)) { + /* a digit */ + int val; + char *end; + if((secnum == -1) && + (3 == sscanf(date, "%02d:%02d:%02d", &hournum, &minnum, &secnum))) { + /* time stamp! */ + date += 8; + } + else if((secnum == -1) && + (2 == sscanf(date, "%02d:%02d", &hournum, &minnum))) { + /* time stamp without seconds */ + date += 5; + secnum = 0; + } + else { + long lval; + int error; + int old_errno; + + old_errno = ERRNO; + SET_ERRNO(0); + lval = strtol(date, &end, 10); + error = ERRNO; + if(error != old_errno) + SET_ERRNO(old_errno); + + if(error) + return PARSEDATE_FAIL; + + if((lval > (long)INT_MAX) || (lval < (long)INT_MIN)) + return PARSEDATE_FAIL; + + val = curlx_sltosi(lval); + + if((tzoff == -1) && + ((end - date) == 4) && + (val <= 1400) && + (indate< date) && + ((date[-1] == '+' || date[-1] == '-'))) { + /* four digits and a value less than or equal to 1400 (to take into + account all sorts of funny time zone diffs) and it is preceded + with a plus or minus. This is a time zone indication. 1400 is + picked since +1300 is frequently used and +1400 is mentioned as + an edge number in the document "ISO C 200X Proposal: Timezone + Functions" at http://david.tribble.com/text/c0xtimezone.html If + anyone has a more authoritative source for the exact maximum time + zone offsets, please speak up! */ + found = TRUE; + tzoff = (val/100 * 60 + val%100)*60; + + /* the + and - prefix indicates the local time compared to GMT, + this we need ther reversed math to get what we want */ + tzoff = date[-1]=='+'?-tzoff:tzoff; + } + + if(((end - date) == 8) && + (yearnum == -1) && + (monnum == -1) && + (mdaynum == -1)) { + /* 8 digits, no year, month or day yet. This is YYYYMMDD */ + found = TRUE; + yearnum = val/10000; + monnum = (val%10000)/100-1; /* month is 0 - 11 */ + mdaynum = val%100; + } + + if(!found && (dignext == DATE_MDAY) && (mdaynum == -1)) { + if((val > 0) && (val<32)) { + mdaynum = val; + found = TRUE; + } + dignext = DATE_YEAR; + } + + if(!found && (dignext == DATE_YEAR) && (yearnum == -1)) { + yearnum = val; + found = TRUE; + if(yearnum < 1900) { + if(yearnum > 70) + yearnum += 1900; + else + yearnum += 2000; + } + if(mdaynum == -1) + dignext = DATE_MDAY; + } + + if(!found) + return PARSEDATE_FAIL; + + date = end; + } + } + + part++; + } + + if(-1 == secnum) + secnum = minnum = hournum = 0; /* no time, make it zero */ + + if((-1 == mdaynum) || + (-1 == monnum) || + (-1 == yearnum)) + /* lacks vital info, fail */ + return PARSEDATE_FAIL; + +#if SIZEOF_TIME_T < 5 + /* 32 bit time_t can only hold dates to the beginning of 2038 */ + if(yearnum > 2037) { + *output = 0x7fffffff; + return PARSEDATE_LATER; + } +#endif + + if(yearnum < 1970) { + *output = 0; + return PARSEDATE_SOONER; + } + + if((mdaynum > 31) || (monnum > 11) || + (hournum > 23) || (minnum > 59) || (secnum > 60)) + return PARSEDATE_FAIL; /* clearly an illegal date */ + + tm.tm_sec = secnum; + tm.tm_min = minnum; + tm.tm_hour = hournum; + tm.tm_mday = mdaynum; + tm.tm_mon = monnum; + tm.tm_year = yearnum - 1900; + + /* my_timegm() returns a time_t. time_t is often 32 bits, even on many + architectures that feature 64 bit 'long'. + + Some systems have 64 bit time_t and deal with years beyond 2038. However, + even on some of the systems with 64 bit time_t mktime() returns -1 for + dates beyond 03:14:07 UTC, January 19, 2038. (Such as AIX 5100-06) + */ + t = my_timegm(&tm); + + /* time zone adjust (cast t to int to compare to negative one) */ + if(-1 != (int)t) { + + /* Add the time zone diff between local time zone and GMT. */ + long delta = (long)(tzoff!=-1?tzoff:0); + + if((delta>0) && (t + delta < t)) + return -1; /* time_t overflow */ + + t += delta; + } + + *output = t; + + return PARSEDATE_OK; +} + +time_t curl_getdate(const char *p, const time_t *now) +{ + time_t parsed; + int rc = parsedate(p, &parsed); + (void)now; /* legacy argument from the past that we ignore */ + + switch(rc) { + case PARSEDATE_OK: + case PARSEDATE_LATER: + case PARSEDATE_SOONER: + return parsed; + } + /* everything else is fail */ + return -1; +} + +/* + * Curl_gmtime() is a gmtime() replacement for portability. Do not use the + * gmtime_r() or gmtime() functions anywhere else but here. + * + * To make sure no such function calls slip in, we define them to cause build + * errors, which is why we use the name within parentheses in this function. + * + */ + +CURLcode Curl_gmtime(time_t intime, struct tm *store) +{ + const struct tm *tm; +#ifdef HAVE_GMTIME_R + /* thread-safe version */ + tm = (struct tm *)gmtime_r(&intime, store); +#else + tm = gmtime(&intime); + if(tm) + *store = *tm; /* copy the pointed struct to the local copy */ +#endif + + if(!tm) + return CURLE_BAD_FUNCTION_ARGUMENT; + return CURLE_OK; +} |