diff options
| -rw-r--r-- | ChangeLog | 8 | ||||
| -rw-r--r-- | time/mktime.c | 30 |
2 files changed, 26 insertions, 12 deletions
@@ -1,5 +1,13 @@ 2012-05-23 Paul Eggert <eggert@cs.ucla.edu> + mktime: do not assume 'long' is wide enough + * time/mktime.c (verify): Move decl up. + (long_int): New type. + (leapyear, ydhms_diff, guess_time_tm, __mktime_internal): Use it, + to remove assumption in the code that 'long' is wide enough to + store year values. This assumption is not true on x32 and on + some non-glibc platforms. + mktime: merge wrapv change from gnulib * time/mktime.c (WRAPV): New macro. (time_t_avg, time_t_add_ok, time_t_int_add_ok): New static functions. diff --git a/time/mktime.c b/time/mktime.c index 8a2b228..6d4db69 100644 --- a/time/mktime.c +++ b/time/mktime.c @@ -68,6 +68,17 @@ # endif #endif +/* Verify a requirement at compile-time (unlike assert, which is runtime). */ +#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; } + +/* A signed type that is at least one bit wider than int. */ +#if INT_MAX <= LONG_MAX / 2 +typedef long int long_int; +#else +typedef long long int long_int; +#endif +verify (long_int_is_wide_enough, INT_MAX == INT_MAX * (long_int) 2 / 2); + /* Shift A right by B bits portably, by dividing A by 2**B and truncating towards minus infinity. A and B should be free of side effects, and B should be in the range 0 <= B <= INT_BITS - 2, where @@ -124,9 +135,6 @@ #endif #define TIME_T_MIDPOINT (SHR (TIME_T_MIN + TIME_T_MAX, 1) + 1) -/* Verify a requirement at compile-time (unlike assert, which is runtime). */ -#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; } - verify (time_t_is_integer, TYPE_IS_INTEGER (time_t)); verify (twos_complement_arithmetic, TYPE_TWOS_COMPLEMENT (int)); @@ -136,7 +144,7 @@ verify (base_year_is_a_multiple_of_100, TM_YEAR_BASE % 100 == 0); /* Return 1 if YEAR + TM_YEAR_BASE is a leap year. */ static inline int -leapyear (long int year) +leapyear (long_int year) { /* Don't add YEAR to TM_YEAR_BASE, as that might overflow. Also, work even if YEAR is negative. */ @@ -182,12 +190,10 @@ const unsigned short int __mon_yday[2][13] = detect overflow. */ static inline time_t -ydhms_diff (long int year1, long int yday1, int hour1, int min1, int sec1, +ydhms_diff (long_int year1, long_int yday1, int hour1, int min1, int sec1, int year0, int yday0, int hour0, int min0, int sec0) { verify (C99_integer_division, -1 / 2 == 0); - verify (long_int_year_and_yday_are_wide_enough, - INT_MAX <= LONG_MAX / 2 || TIME_T_MAX <= UINT_MAX); /* Compute intervening leap days correctly even if year is negative. Take care to avoid integer overflow here. */ @@ -265,7 +271,7 @@ time_t_int_add_ok (time_t a, int b) If overflow occurs, yield the minimal or maximal value, except do not yield a value equal to *T. */ static time_t -guess_time_tm (long int year, long int yday, int hour, int min, int sec, +guess_time_tm (long_int year, long_int yday, int hour, int min, int sec, const time_t *t, const struct tm *tp) { if (tp) @@ -368,8 +374,8 @@ __mktime_internal (struct tm *tp, int mon_remainder = mon % 12; int negative_mon_remainder = mon_remainder < 0; int mon_years = mon / 12 - negative_mon_remainder; - long int lyear_requested = year_requested; - long int year = lyear_requested + mon_years; + long_int lyear_requested = year_requested; + long_int year = lyear_requested + mon_years; /* The other values need not be in range: the remaining code handles minor overflows correctly, @@ -381,8 +387,8 @@ __mktime_internal (struct tm *tp, int mon_yday = ((__mon_yday[leapyear (year)] [mon_remainder + 12 * negative_mon_remainder]) - 1); - long int lmday = mday; - long int yday = mon_yday + lmday; + long_int lmday = mday; + long_int yday = mon_yday + lmday; time_t guessed_offset = *offset; |