in libs/curl/lib/parsedate.c [357:571]
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;
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 */
size_t len = 0;
const char *p = date;
while(ISALPHA(*p) && (len < NAME_LEN)) {
p++;
len++;
}
if(len != NAME_LEN) {
if(wdaynum == -1) {
wdaynum = checkday(date, len);
if(wdaynum != -1)
found = TRUE;
}
if(!found && (monnum == -1)) {
monnum = checkmonth(date, len);
if(monnum != -1)
found = TRUE;
}
if(!found && (tzoff == -1)) {
/* this just must be a time zone string */
tzoff = checktz(date, len);
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) &&
match_time(date, &hournum, &minnum, &secnum, &end)) {
/* time stamp */
date = end;
}
else {
long lval;
int error;
int old_errno;
old_errno = errno;
errno = 0;
lval = strtol(date, &end, 10);
error = errno;
if(errno != old_errno)
errno = old_errno;
if(error)
return PARSEDATE_FAIL;
#if LONG_MAX != INT_MAX
if((lval > (long)INT_MAX) || (lval < (long)INT_MIN))
return PARSEDATE_FAIL;
#endif
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 their 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 < 100) {
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;
#ifdef HAVE_TIME_T_UNSIGNED
if(yearnum < 1970) {
/* only positive numbers cannot return earlier */
*output = TIME_T_MIN;
return PARSEDATE_SOONER;
}
#endif
#if (SIZEOF_TIME_T < 5)
#ifdef HAVE_TIME_T_UNSIGNED
/* an unsigned 32-bit time_t can only hold dates to 2106 */
if(yearnum > 2105) {
*output = TIME_T_MAX;
return PARSEDATE_LATER;
}
#else
/* a signed 32-bit time_t can only hold dates to the beginning of 2038 */
if(yearnum > 2037) {
*output = TIME_T_MAX;
return PARSEDATE_LATER;
}
if(yearnum < 1903) {
*output = TIME_T_MIN;
return PARSEDATE_SOONER;
}
#endif
#else
/* The Gregorian calendar was introduced 1582 */
if(yearnum < 1583)
return PARSEDATE_FAIL;
#endif
if((mdaynum > 31) || (monnum > 11) ||
(hournum > 23) || (minnum > 59) || (secnum > 60))
return PARSEDATE_FAIL; /* clearly an illegal date */
/* time2epoch() returns a time_t. time_t is often 32 bits, sometimes even on
architectures that feature a 64 bits 'long' but ultimately time_t is the
correct data type to use.
*/
t = time2epoch(secnum, minnum, hournum, mdaynum, monnum, yearnum);
/* Add the time zone diff between local time zone and GMT. */
if(tzoff == -1)
tzoff = 0;
if((tzoff > 0) && (t > TIME_T_MAX - tzoff)) {
*output = TIME_T_MAX;
return PARSEDATE_LATER; /* time_t overflow */
}
t += tzoff;
*output = t;
return PARSEDATE_OK;
}