CheckSetvbufInvalidMode sat inside the #ifdef _WIN32 block of
CheckStandardStreamDeleteSharing while main calls it on every platform,
so the Linux build failed. It uses nothing Windows-specific: move it
above the block so the check also runs on Linux.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
GuestStandardStreams used setvbuf only with valid modes.
CheckSetvbufInvalidMode requires modes 3, -1 and INT_MAX to return EOF,
as FreeBSD's setvbuf does for any mode other than _IOFBF, _IOLBF and
_IONBF (C11 7.21.5.6: nonzero for an invalid mode). A rejected call with
a buffer must not adopt it: a character written afterwards stays out of
that buffer and the stream still writes and reads back normally.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
fputws and wprintf write a UTF-16 surrogate pair as one four-byte
UTF-8 sequence, but fgetwc decoded that sequence into a single code
point above 0xFFFF, which is not a 16-bit guest wchar_t value, and
fgetws stored it truncated: fputws(u"A\U0001F600\n") read back as
A, U+F600, newline.
fgetwc now returns the high surrogate and keeps the low one in the
stream for the next read, so fgetws stores the pair, also when the
buffer fills between the two halves. A successful seek discards it,
as FreeBSD's fseeko resets the stream's mbstate. Sequences that
decode to an overlong form or above U+10FFFF, and lead bytes F8 to
FF, fail with EILSEQ instead of returning made-up characters; the
three-byte surrogates that fputwc writes for a single unit are still
read back as that unit.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01QegaHM5QeCynUQ2ZLWHE4b
On Windows the UCRT drops a write that directly follows a read on an r+,
w+ or a+ stream: fputc and fprintf report success, fwrite returns 0 and
fputs returns EOF, all without the error indicator, and the file is left
unchanged, also after an fflush. On a stream open only for reading, fputc
after a read reports success as well.
Writes now first do what FreeBSD 11.4's __swsetup does: a stream open only
for reading fails with EBADF and sets the error indicator, and an update
stream that is reading drops its read buffer and ungetc data, clears end
of file and writes at the descriptor's offset. This covers fwrite, fputs,
fputc, putc_unlocked, fprintf, fprintf_s, fputwc, fputws, fwprintf,
fwprintf_s, puts and wprintf, and printf, vprintf and printf_s, which
write to standard output through PrintWindows and now return -1 there
instead of throwing.
Linux is unchanged: glibc writes at the stream position, which the libc
technical debt now records.
The fgetws in the libc.prx that titles ship (the same 133 bytes in the
copies of PPSA13934, PPSA07923 and PPSA05916, read from disassembly)
differs from this one in two cases:
- A size below 2 returns null at once, without writing the buffer,
errno or the stream (cmp $0x2,%esi; jge, else the null result). Here a
size of 1 stored a NUL and returned the buffer, and a size of 0 or less
set the stream error and errno 22.
- When fgetwc returns -1 after characters were stored, the console
null-terminates and returns the buffer; it returns null only when
nothing was stored, and never checks ferror. Here a read error after
some characters returned null.
The rest already matches: each fgetwc result is stored as its low 16 bits
(mov %ax,(%rbx)), and the newline test compares all 32 bits. A null buffer
or stream, which the console dereferences, keeps failing with errno 22.
guest_standard_streams now expects the console results for sizes 1, 0
and -1 and for an invalid byte after a stored character; its fgetwc error
indicator check is unchanged. The libc debt entry cites the reading and
what it leaves unverified.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
On Linux sscanf, vsscanf, fscanf and sscanf_s hand their conversions to
glibc. Since glibc 2.38, code built as GNU C++ calls the C23 entry
points (__isoc23_vsscanf, __isoc23_vfscanf, __isoc23_sscanf), whose %i
reads a 0b/0B binary prefix. On main,
sscanf("0b101 x", "%i%n%7s", &value, &end, rest) stores value 5 and
end 5 and leaves "x" for the %s; " -0B11" gives -3. TechnicalDebt
records this.
FreeBSD's %i knows only the 0 and 0x prefixes. FreeBSD 11.4
lib/libc/stdio/vfscanf.c, parseint, lines 345-353 and 371-380:
case '0':
if (base == 0) {
base = 8;
flags |= PFXOK;
}
...
/* letters ok iff hex */
case 'A': case 'B': case 'C':
case 'D': case 'E': case 'F':
case 'a': case 'b': case 'c':
case 'd': case 'e': case 'f':
/* no need to fix base here */
if (base <= 10)
break; /* not legal here */
so "0b101" stores 0, consumes the "0" and leaves "b101", as C17 does
and as the strtol family here already does.
With glibc the scanf family now calls __isoc99_vsscanf and
__isoc99_vfscanf, the entry points GNU C++ used before glibc 2.38
(exported since 2.7), which read %i without the binary prefix. Other
hosts keep std::vsscanf and std::vfscanf. The TechnicalDebt entry is
removed.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
fflush() passed every stream to glibc's fflush(). For a stream that is
reading, glibc seeks the descriptor back and drops the read buffer, and
with a pushed-back character it gets the position wrong: after fgetc()
returned 'a' from "abcdef\n" and ungetc('Z'), fflush() returned 0 and
the next fread() returned "bcdef\n\n". The pushed-back 'Z' was lost and
the last byte came back twice.
FreeBSD's fflush() writes out only a stream that is writing and leaves
every other stream as it is, lib/libc/stdio/fflush.c:
if ((fp->_flags & (__SWR | __SRW)) == 0)
retval = 0;
else
retval = __sflush(fp);
and __sflush():
t = fp->_flags;
if ((t & __SWR) == 0)
return (0);
fflush() on Linux now returns 0 without calling the host for a stream
whose last operation was not a write (__fwriting() is 0). fflush(NULL)
and streams that are writing are unchanged.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
fopen and freopen leave an "a+" stream where the host CRT puts it, at
the start of the file. On main, after fopen(file, "a+") on a 7-byte
file, ftell returns 0 and the first fgetc returns the first byte of the
file. FreeBSD seeks every append-mode stream to the end when it opens
it, so ftell returns 7 and a read before any fseek returns EOF. Code
that opens a log or save file with "a+" and tests ftell(f) == 0 to see
whether the file is new treats every existing file as empty.
FreeBSD 11.4 lib/libc/stdio/fopen.c (fopen), and the same lines in
lib/libc/stdio/freopen.c (freopen):
if (oflags & O_APPEND) {
fp->_flags2 |= __S2OAP;
(void)_sseek(fp, (fpos_t)0, SEEK_END);
}
lib/libc/stdio/flags.c sets O_APPEND for every mode that starts with 'a':
case 'a': /* open for appending */
ret = __SWR;
m = O_WRONLY;
o = O_CREAT | O_APPEND;
fopen and freopen now seek a stream opened with an 'a' mode to the end
of the file, ignoring a failed seek as FreeBSD does. Writes still go to
the end through O_APPEND.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
fdopen only took a fixed list of 15 mode strings and failed with EINVAL
for any other, so "rt", "r+t", "re", "rbe" or "rw" gave NULL. FreeBSD's
fdopen parses the mode with __sflags (lib/libc/stdio/flags.c): after
r, w or a it takes b, +, x, e and v and stops at the first other
character ("default: known = 0;"), and only a bad first character or x
on a read-only mode fail with EINVAL. fopen and freopen already parse
modes this way through ParseFileMode (#2033).
fdopen now uses ParseFileMode as well and passes the host its normalised
mode without x, which FreeBSD's fdopen ignores.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
The guest fgets handed the size straight to the host. With a size of 0
glibc and the Windows runtime return NULL without setting errno or the
stream error indicator, and a negative size goes to the Windows
invalid-parameter path. FreeBSD's fgets checks n <= 0 before reading:
it sets __SERR on the stream, sets errno to EINVAL and returns NULL,
leaving the buffer and the file position untouched.
fgets_nid_postfix now does the same before calling the host. The
FileStream flag it uses was only set for encoding errors so far and is
renamed from SetEncodingError/encodingError to SetError/guestError; it
already stays set until clearerr like __SERR.
guest_standard_streams checks sizes 0, -1 and INT_MIN (NULL, errno 22,
error indicator set and cleared by clearerr, buffer and position
untouched) and that a following read still returns the line; it fails
without the change.
Fixes#3084
AI-assisted: yes
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Porpoise PPSA99764 stops after pthread_attr_* (#3494) with the
predicted `FAIL: unresolved ELF import h05OHOMZNMw from
libSceLibcInternal.prx` (idx 311, call site 0x8EC37); RetroArch
PPSA99169 imports it at idx 448 (call site 0xA4A27). h05OHOMZNMw is
ftrylockfile by tools/nid_names.py and aerolib.csv (zecoxao/sce_symbols
2883963a); ps5-payload-dev/sdk f5d40f02 declares
`int ftrylockfile(FILE *)` in include/freebsd/stdio.h.
ftrylockfile tries the same host CRT stream lock that flockfile,
funlockfile and every locking host stdio call on the stream take, so
no second lock exists beside the one stdio uses. It returns 0 when the
lock is acquired or already owned by the caller (recursive, released by
as many funlockfile calls) and -1 when another thread holds it, as
FreeBSD 8c639945 lib/libc/stdio/_flock_stub.c:89-104 does. Linux calls
glibc ftrylockfile. UCRT has no try variant of _lock_file, so Windows
calls TryEnterCriticalSection on the CRITICAL_SECTION that _lock_file
enters (__crt_stdio_stream_data::_lock, ucrt/inc/corecrt_internal_stdio.h,
same layout in Windows SDK 10.0.19041, 10.0.22621 and 10.0.26100). A
null or closed stream throws. The UCRT layout dependency is recorded in
TechnicalDebt.
guest_standard_streams covers trylock on an unlocked stream, re-entry
by the owner, failure from another thread while held (also after one of
two unlocks and while another thread holds flockfile), stdio calls
from another thread blocking on the trylock-held lock, release order,
and null and closed streams.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
C17 7.21.6.2p16 returns EOF only if input fails before the first conversion completes, and a suppressed conversion completes. FreeBSD counts it in nconversions (vfscanf.c, releng/11.4, lines 799-805). The host scanf returned EOF there, so sscanf("12", "%*d%d", &v) reported EOF instead of 0. Each suppressed conversion now records its end with a %n and a result of EOF becomes 0 when one was recorded.
Use unlocked POSIX EOF/error queries after unlocked byte operations so status synchronization cannot reacquire the stream lock. Keep the verified UCRT status calls on Windows, and cover byte, status, error, and held-lock behavior.
Co-authored-by: MarcZX100 <[email protected]>
Adrià