This is to better merge with a future version of glibc. This merges a glibc patch by Florian Weimer in: https://sourceware.org/pipermail/libc-alpha/2024-October/160308.html * lib/mktime.c (convert_time): Accept a boolean flag instead of a function pointer. All callers changed. --- ChangeLog | 9 ++++++ lib/mktime-internal.h | 9 +++--- lib/mktime.c | 71 ++++++++++++++++++++++--------------------- lib/timegm.c | 2 +- 4 files changed, 50 insertions(+), 41 deletions(-)
diff --git a/ChangeLog b/ChangeLog index 22a40c3d58..08a452130d 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,12 @@ +2024-10-03 Paul Eggert <egg...@cs.ucla.edu> + + mktime: refactor convert_time + This is to better merge with a future version of glibc. + This merges a glibc patch by Florian Weimer in: + https://sourceware.org/pipermail/libc-alpha/2024-October/160308.html + * lib/mktime.c (convert_time): Accept a boolean flag instead + of a function pointer. All callers changed. + 2024-10-03 Bruno Haible <br...@clisp.org> bcp47: Add tests. diff --git a/lib/mktime-internal.h b/lib/mktime-internal.h index 0693aaf140..3e2848c121 100644 --- a/lib/mktime-internal.h +++ b/lib/mktime-internal.h @@ -71,9 +71,8 @@ typedef int mktime_offset_t; #endif /* Subroutine of mktime. Return the time_t representation of TP and - normalize TP, given that a struct tm * maps to a time_t as performed - by FUNC. Record next guess for localtime-gmtime offset in *OFFSET. */ -extern __time64_t __mktime_internal (struct tm *tp, - struct tm *(*func) (__time64_t const *, - struct tm *), + normalize TP, given that a struct tm * maps to a time_t. If + LOCAL, the mapping is performed by localtime_r, otherwise by gmtime_r. + Record next guess for localtime-gmtime offset in *OFFSET. */ +extern __time64_t __mktime_internal (struct tm *tp, bool local, mktime_offset_t *offset) attribute_hidden; diff --git a/lib/mktime.c b/lib/mktime.c index 744a7277bb..92ac9735b0 100644 --- a/lib/mktime.c +++ b/lib/mktime.c @@ -251,29 +251,31 @@ tm_diff (long_int year, long_int yday, int hour, int min, int sec, tp->tm_hour, tp->tm_min, tp->tm_sec); } -/* Use CONVERT to convert T to a struct tm value in *TM. T must be in - range for __time64_t. Return TM if successful, NULL (setting errno) on - failure. */ +/* Convert T to a struct tm value in *TM. Use localtime64_r if LOCAL, + otherwise gmtime64_r. T must be in range for __time64_t. Return + TM if successful, NULL (setting errno) on failure. */ static struct tm * -convert_time (struct tm *(*convert) (const __time64_t *, struct tm *), - long_int t, struct tm *tm) +convert_time (bool local, long_int t, struct tm *tm) { __time64_t x = t; - return convert (&x, tm); + if (local) + return __localtime64_r (&x, tm); + else + return __gmtime64_r (&x, tm); } -/* Use CONVERT to convert *T to a broken down time in *TP. - If *T is out of range for conversion, adjust it so that - it is the nearest in-range value and then convert that. - A value is in range if it fits in both __time64_t and long_int. - Return TP on success, NULL (setting errno) on failure. */ +/* Convert *T to a broken down time in *TP (as if by localtime if + LOCAL, otherwise as if by gmtime). If *T is out of range for + conversion, adjust it so that it is the nearest in-range value and + then convert that. A value is in range if it fits in both + __time64_t and long_int. Return TP on success, NULL (setting + errno) on failure. */ static struct tm * -ranged_convert (struct tm *(*convert) (const __time64_t *, struct tm *), - long_int *t, struct tm *tp) +ranged_convert (bool local, long_int *t, struct tm *tp) { long_int t1 = (*t < mktime_min ? mktime_min : *t <= mktime_max ? *t : mktime_max); - struct tm *r = convert_time (convert, t1, tp); + struct tm *r = convert_time (local, t1, tp); if (r) { *t = t1; @@ -294,7 +296,7 @@ ranged_convert (struct tm *(*convert) (const __time64_t *, struct tm *), long_int mid = long_int_avg (ok, bad); if (mid == ok || mid == bad) break; - if (convert_time (convert, mid, tp)) + if (convert_time (local, mid, tp)) ok = mid, oktm = *tp; else if (errno != EOVERFLOW) return NULL; @@ -310,29 +312,28 @@ ranged_convert (struct tm *(*convert) (const __time64_t *, struct tm *), } -/* Convert *TP to a __time64_t value, inverting - the monotonic and mostly-unit-linear conversion function CONVERT. - Use *OFFSET to keep track of a guess at the offset of the result, +/* Convert *TP to a __time64_t value. If LOCAL, the reverse mapping + is performed as if localtime, otherwise as if by gmtime. Use + *OFFSET to keep track of a guess at the offset of the result, compared to what the result would be for UTC without leap seconds. - If *OFFSET's guess is correct, only one CONVERT call is needed. - If successful, set *TP to the canonicalized struct tm; + If *OFFSET's guess is correct, only one reverse mapping call is + needed. If successful, set *TP to the canonicalized struct tm; otherwise leave *TP alone, return ((time_t) -1) and set errno. This function is external because it is used also by timegm.c. */ __time64_t -__mktime_internal (struct tm *tp, - struct tm *(*convert) (const __time64_t *, struct tm *), - mktime_offset_t *offset) +__mktime_internal (struct tm *tp, bool local, mktime_offset_t *offset) { struct tm tm; - /* The maximum number of probes (calls to CONVERT) should be enough - to handle any combinations of time zone rule changes, solar time, - leap seconds, and oscillations around a spring-forward gap. - POSIX.1 prohibits leap seconds, but some hosts have them anyway. */ + /* The maximum number of probes should be enough to handle any + combinations of time zone rule changes, solar time, leap seconds, + and oscillations around a spring-forward gap. POSIX.1 prohibits + leap seconds, but some hosts have them anyway. */ int remaining_probes = 6; - /* Time requested. Copy it in case CONVERT modifies *TP; this can - occur if TP is localtime's returned value and CONVERT is localtime. */ + /* Time requested. Copy it in case gmtime/localtime modify *TP; + this can occur if TP is localtime's returned value and CONVERT is + localtime. */ int sec = tp->tm_sec; int min = tp->tm_min; int hour = tp->tm_hour; @@ -390,7 +391,7 @@ __mktime_internal (struct tm *tp, while (true) { - if (! ranged_convert (convert, &t, &tm)) + if (! ranged_convert (local, &t, &tm)) return -1; long_int dt = tm_diff (year, yday, hour, min, sec, &tm); if (dt == 0) @@ -469,7 +470,7 @@ __mktime_internal (struct tm *tp, if (! ckd_add (&ot, t, delta * direction)) { struct tm otm; - if (! ranged_convert (convert, &ot, &otm)) + if (! ranged_convert (local, &ot, &otm)) return -1; if (! isdst_differ (isdst, otm.tm_isdst)) { @@ -479,7 +480,7 @@ __mktime_internal (struct tm *tp, &otm); if (mktime_min <= gt && gt <= mktime_max) { - if (convert_time (convert, gt, &tm)) + if (convert_time (local, gt, &tm)) { t = gt; goto offset_found; @@ -493,7 +494,7 @@ __mktime_internal (struct tm *tp, /* No unusual DST offset was found nearby. Assume one-hour DST. */ t += 60 * 60 * dst_difference; - if (mktime_min <= t && t <= mktime_max && convert_time (convert, t, &tm)) + if (mktime_min <= t && t <= mktime_max && convert_time (local, t, &tm)) goto offset_found; __set_errno (EOVERFLOW); @@ -520,7 +521,7 @@ __mktime_internal (struct tm *tp, __set_errno (EOVERFLOW); return -1; } - if (! convert_time (convert, t, &tm)) + if (! convert_time (local, t, &tm)) return -1; } @@ -542,7 +543,7 @@ __mktime64 (struct tm *tp) # if defined _LIBC || NEED_MKTIME_WORKING static mktime_offset_t localtime_offset; - return __mktime_internal (tp, __localtime64_r, &localtime_offset); + return __mktime_internal (tp, true, &localtime_offset); # else # undef mktime return mktime (tp); diff --git a/lib/timegm.c b/lib/timegm.c index e5cf30c019..1f1f66c61b 100644 --- a/lib/timegm.c +++ b/lib/timegm.c @@ -31,7 +31,7 @@ __timegm64 (struct tm *tmp) { static mktime_offset_t gmtime_offset; tmp->tm_isdst = 0; - return __mktime_internal (tmp, __gmtime64_r, &gmtime_offset); + return __mktime_internal (tmp, false, &gmtime_offset); } #if defined _LIBC && __TIMESIZE != 64 -- 2.43.0
