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+/***************************************************************************
+ * _ _ ____ _
+ * 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;
+}