When file offset tends to be negative due to internal and ungetc buffers
additions counted, try to discard some ungetc data first, then return EBADF.
Later one can happens if lseek(fileno(fd),...) called f.e. POSIX says that
ungetc beyond beginning of the file results are undefined, so we can just
discard some of ungetc data in that case.
Don't rely on gcc cast when checking for overflow, use OFF_MAX.
Cosmetique.
Resulting fseek() offset must fit in long, required by POSIX (pointed by bde),
so add LONG_MAX and final tests for it.
rewind.c:
1) add missing __sinit() as in fseek() it pretends to be.
2) use clearerr_unlocked() since we already lock stream before _fseeko()
3) don't zero errno at the end, it explicitely required by POSIX as the
only one method to test rewind() error condition.
4) don't clearerr() if error happens in _fseeko()
"[EINVAL] ... The resulting file-position indicator would be set to a
negative value."
Moreover, in real life negative seek in stdio cause EOF indicator cleared
and not set again forever even if EOF returned.
2) Catch few possible off_t overflows.
Reviewed by: arch discussion
It was foiled because of dynamic copy relocations that caused compile-time
space to be reserved in .bss and at run time a blob of data was copied to
that space and everything used the .bss version.. The problem is that
the space is reserved at compile time, not runtime... So we *still* could
not change the size of FILE. Sigh. :-(
Replace it with something that does actually work and really does let us
make 'FILE' extendable. It also happens to be the same as Linux does in
glibc, but has the slight cost of a pointer. Note that this is the
same cost that 'fp = fopen(), fprintf(fp, ...); fclose(fp);' has.
Fortunately, actual references to stdin/out/err are not all that common
since we have implicit stdin/out/err-using versions of functions
(printf() vs. fprintf()).
Avoid using parenthesis enclosure macros (.Pq and .Po/.Pc) with plain text.
Not only this slows down the mdoc(7) processing significantly, but it also
has an undesired (in this case) effect of disabling hyphenation within the
entire enclosed block.
instead of #pragma weak to create weak definitions. This macro is
improperly named, though, since a weak definition is not the same
thing as a weak reference.
Suggested by: bde
lock definitions to it. flockfile state is now allocated
along with the rest of FILE. This eliminates the need for a
separate allocation of flockfile state as well as eliminating
the mutex/lock used to serialize its allocation.
This is about to be replaced anyway by initialization explicitly
instead of lazily, and reducing the complexity of it. As it is
now, this will work fine, however.
while with threaded software in -CURRENT acting very "weird". It has
seemed, for example, in Mozilla that threads attempting to do host
lookups have been locking up. That's exactly the case.
There was a race condition in the implementation of the initialization
of the mutex used to protect FILE operations, first of all: multiple
instances of FLOCKFILE() in libc could occur on the same FILE at
the same time and cause strange behavior by overwriting eachothers'
creation of the mutex and the rest of the file lock.
Secondly, it's not appropriate to test the "validity" of the file
descriptor referenced by the FILE; if the code is calling FLOCKFILE()
or FUNLOCKFILE(), it wants the FILE to be locked or unlocked, not
to be locked or unlocked on the condition that _file is >= 0. This
also could quite easily cause leaks by failing to perform the lock or
unlock operation when it actually is needed.
Mozilla now works again on -CURRENT when linked to libc_r.so.5 and
libc.so.5.
ABI change. There is some serious evilness here to work around some
gcc weaknesses. We need to know the sizeof(FILE) manually until __sF
goes away in the next major bump. We have the size for Alpha and i386,
missing is ia64, ppc and sparc* (and i386 with 64 bit longs).
At some point down the track we can change the stdin etc #defines to
stop hard coding the size of FILE into application binaries.
Lots of head scratching and ideas and testing by: green, imp
causing some versions of as to dump core. This survived make
buildworld/installworld and the building gettext port afterwards.
Submitted by: <nnd@mail.nsk.ru> "N.Dudorov"
Reviewed by: "Daniel M. Eischen" <eischen@vigrid.com>
o Back out the __std* stuff. Can't figure out how to do this right now,
so we'll save it for late.
o use _up as a pointer for extra fields that we need to access.
o back out the libc major version bump.
Submitted by: green
reviewed by: peter, imp, green, obrien (to varying degrees).
We'll fix the "how do we stop encoding sizeof(FILE) in binaries" part
later.
