On Windows, localtime_s moves a time outside the host range into it by
subtracting whole 400-year cycles, computed as
cycles * CALENDAR_CYCLE_SECONDS. For times within about 7.2e9 seconds of
INT64_MIN that product overflows int64, which is undefined behaviour:
built with -fsanitize=undefined -fsanitize-trap=all, guest_time_conversion
traps there on its INT64_MIN case.
Take the remainder of the time by the cycle length instead. It is the
same value for every input that did not overflow, so results do not
change, and the extreme inputs still fail the year range check.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Nested conversions such as the one closing mktime no longer re-read TZ, so
the instant and the normalised fields come from one zone. The race test now
covers mktime and strftime.
Copy the guest TZ under the guest environment lock so a concurrent setenv
cannot free it while it is read, and hold one lock across the zone switch
and the conversion so the fields of two zones are never mixed. Document the
host rejection, Windows zone name and stale tm_zone limits.
Guest setenv, putenv and unsetenv only change the guest environment, while
the time conversions read the host TZ, so a guest that set TZ and called
tzset still got host local time. Copy a changed guest TZ to the host before
each local conversion and call tzset again.
A local time before 1900 was converted 400-year cycles later, where the
zone's modern rules apply. macOS's localtime_r gives such a time the
zone's historical offset, local mean time before its first transition,
so mktime(localtime(t)) no longer returned t in a region zone: +422 s in
America/Los_Angeles (LMT -7:52:58), -392 in Europe/Berlin, +1408 in
Asia/Kolkata (-530 under its MMT offset, from 1870 through 1 January
1900), -3228 in America/Argentina/Buenos_Aires (-4608 under its CMT
offset). jotitadev found this in review.
On macOS mktime now solves a local time before 2 January 1900, where the
host's mktime no longer applies, directly: it subtracts the offset
localtime_r gives for a candidate time from the local fields and repeats
until the offset holds, at most four times. Windows and local times from
2 January 1900 on are unchanged.
macOS's mktime returns -1 for every year before 1900, so a guest mktime of
such a time failed there although localtime converts it. Windows already
moves a time outside its CRT's range a whole number of 400-year Gregorian
cycles, where weekdays and leap years repeat, converts it there and moves
the result back. macOS now does the same below 1 January 1900; each host
keeps its own range, and Windows's is unchanged.
ES-DE in RetroArch (PPSA99169) imports tzname from libSceLibcInternal and
fails to load without it; ICU's uprv_tzname reads it after localtime. It
points at the host's zone names and tzset refreshes it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
strftime handed most conversions to the host's strftime, which differs
from FreeBSD 11's for E and O modifiers on conversions glibc does not
pair with them (%Ea was printed literally), padding flags on %+ and %v,
years outside 1000 to 9999 (%Y printed 899 and -1 where FreeBSD prints
0899 and -001), and out-of-range fields (%I of hour 100, %u of weekday
8). On Windows the padding flags printed nothing. strftime now follows
FreeBSD 11 strftime.c with the C locale on every host, and asctime
follows FreeBSD 11 asctime.c, padding years to four digits and setting
longer years apart.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VZWLdTjf1S57iLgn2rcaFb
PS5MC (PPSA99420) imports wcsftime (XbVXpf5WF28, aerolib) as the last
absent libSceLibcInternal import in its registry order (index 481), so
its predicted stop is:
FAIL: unresolved ELF import XbVXpf5WF28 from libSceLibcInternal.prx
The stop is predicted from the import order, not observed in a run.
wcsftime follows FreeBSD 11.4 lib/libc/locale/wcsftime.c (8c639945):
the wide format is converted with wcsrtombs, strftime fills a buffer of
maxsize * MB_CUR_MAX bytes limited to maxsize, and mbsrtowcs converts
the result back. A format unit that the single-byte C locale of
lib/libc/locale/none.c cannot encode returns 0 with EILSEQ, a maxsize
whose product with MB_CUR_MAX overflows returns 0 with EINVAL, and an
empty or overflowing result or a null buffer returns 0 with errno
unchanged; the ERANGE or EINVAL set by the Windows CRT's strftime is
discarded. A null format or tm throws, as FreeBSD dereferences it.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
difftime and libc_difftime passed their arguments to the host CRT.
UCRT's _difftime64 returns 0 and sets errno to EINVAL when either
argument is negative (common_difftime in ucrt/time/difftime.cpp), so
on Windows difftime(0, -1) returned 0 instead of 1 and every
difference involving a time before 1970 was 0. C17 7.27.2.2 defines
the result as time1 - time0, and FreeBSD 11's difftime
(contrib/tzcode/stdtime/difftime.c) and glibc on the Linux build
compute it for any arguments.
Subtract the smaller time from the larger as uint64_t, which cannot
overflow, convert the difference to double and negate it when time1
is the smaller one, as FreeBSD and glibc's fallback path do. The
result is time1 - time0 rounded once to double on both hosts.
difftime now forwards to libc_difftime like the other aliases in the
file.
asctime passed the guest tm to the host CRT. UCRT's asctime returns
null and sets errno to EINVAL when tm_year is negative or tm_mday is
past the end of the month (common_asctime_s in ucrt/time/asctime.cpp),
so on Windows asctime of any time in the years 1000 to 1899, which
gmtime converts, or of February 29 in a common year returned null.
C17 7.27.3.1 defines the text for every year from 1000 to 9999 when
each member is in its normal range (tm_mday 1 to 31), and glibc on
the Linux build and FreeBSD 11's asctime
(contrib/tzcode/stdtime/asctime.c) print it.
Format the text with the C17 algorithm's format into a thread-local
buffer that fits any member values. As in glibc and FreeBSD, a
weekday or month outside its range is printed as ???, and the year is
computed in 64 bits.
gmtime, localtime, mktime, strftime and asctime took and returned the
host std::tm. The guest's FreeBSD tm has tm_gmtoff and tm_zone after the
nine calendar fields, so on Windows, where std::tm is 36 bytes, a title
reading those fields read past the thread-local result, and gmtime_s left
them unwritten. Windows gmtime_s also accepts only 1969-12-31 12:00 to
3001-01-19 21:59 UTC, where the guest libc converts any time.
Convert through a GuestTm with the guest layout on both hosts. Compute
the UTC fields from the day count, so every time whose year fits an int
converts, and on Windows take the local offset and zone name from the
CRT. gmtime reports the zone as UTC like the guest libc. localtime and
mktime keep the CRT's range on Windows; recorded in TechnicalDebt.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Without TZ, glibc's localtime and mktime run tzset on every call and
re-check /etc/localtime each time. PPSA28997 calls them every frame
during its intro, which then spent most of its time there. TZ is set
to :/etc/localtime when unset, so the zone is read once.
- libc: reserve guest memory in one arena below the PS5 map limit with
MEM_WRITE_WATCH (GuestArena) and a caching guest heap; the allocation
registry gains a generation counter, an invalidator callback for the
driver's page cache and a pin waiter for leased ranges. This replaces
the fault-based GuestMemoryTracking/GuestMemoryBacking layer, whose
files are removed.
- libkernel: mmap/mprotect/munmap on the arena, flexible memory budget,
real sceKernelVirtualQuery; POSIX pthread layer, rwlocks, timed locks,
TSD, event flags; 0.5 ms scheduler tick and high-resolution sleeps;
TSC/clock/time functions; file APIs return SCE errno codes; the APR
file-streaming API.
- libc: vectored crash reporter with backtraces for fatal exceptions,
SIGABRT, UCRT invalid parameters and process exit; SSE4a EXTRQ/INSERTQ
emulation for Intel hosts; %ls/%lc/%S/%C with the guest's 16-bit
wchar_t; hand-written setjmp/longjmp for the guest jmp_buf; a path
alias table for short save-data mount points; more string, stdio and
math exports.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0177gthrWEBBfBu5xJDXgBfo
