| Commit message (Expand) | Author | Files | Lines |
|---|
| 2013-08-09 | block all signals, even implementation-internal ones, in faccessat child•••the child process's stack may be insufficient size to support a signal
frame, and there is no reason these signal handlers should run in the
child anyway.
| Rich Felker | 1 | -1/+1 |
| 2013-08-08 | block signals during fork•••there are several reasons for this. some of them are related to race
conditions that arise since fork is required to be async-signal-safe:
if fork or pthread_create is called from a signal handler after the
fork syscall has returned but before the subsequent userspace code has
finished, inconsistent state could result. also, there seem to be
kernel and/or strace bugs related to arrival of signals during fork,
at least on some versions, and simply blocking signals eliminates the
possibility of such bugs.
| Rich Felker | 1 | -0/+3 |
| 2013-08-08 | work around libraries with versioned symbols in dynamic linker•••this commit does not add versioning support; it merely fixes incorrect
lookups of symbols in libraries that contain versioned symbols.
previously, the version information was completely ignored, and
empirically this seems to have resulted in the oldest version being
chosen, but I am uncertain if that behavior was even reliable.
the new behavior being introduced is to completely ignore symbols
which are marked "hidden" (this seems to be the confusing nomenclature
for non-current-version) when versioning is present. this should solve
all problems related to libraries with symbol versioning as long as
all binaries involved are up-to-date (compatible with the
latest-version symbols), and it's the needed behavior for dlsym under
all circumstances.
| Rich Felker | 1 | -11/+14 |
| 2013-08-08 | sys/personality.h: add missing C++ compat | rofl0r | 1 | -0/+7 |
| 2013-08-08 | sys/personality.h: add missing macros | rofl0r | 1 | -0/+33 |
| 2013-08-07 | add Big5 charset support to iconv•••at this point, it is just the common base charset equivalent to
Windows CP 950, with no further extensions. HKSCS and possibly other
supersets will be added later. other aliases may need to be added too.
| Rich Felker | 2 | -0/+1066 |
| 2013-08-07 | make fcvt decimal point location for zero make more sense•••the (obsolete) standard allows either 0 or 1 for the decimal point
location in this case, but since the number of zero digits returned in
the output string (in this implementation) is one more than the number
of digits the caller requested, it makes sense for the decimal point
to be logically "after" the first digit. in a sense, this change goes
with the previous commit which fixed the value of the decimal point
location for non-zero inputs.
| Rich Felker | 1 | -1/+1 |
| 2013-08-07 | fix ecvt/fcvt decimal point position output•••these functions are obsolete and have no modern standard. the text in
SUSv2 is highly ambiguous, specifying that "negative means to the left
of the returned digits", which suggested to me that 0 would mean to
the right of the first digit. however, this does not agree with
historic practice, and the Linux man pages are more clear, specifying
that a negative value means "that the decimal point is to the left of
the start of the string" (in which case, 0 would mean the start of the
string, in accordance with historic practice).
| Rich Felker | 1 | -1/+1 |
| 2013-08-05 | iconv support for legacy Korean encodings•••like for other character sets, stateful iso-2022 form is not supported
yet but everything else should work. all charset aliases are treated
the same, as Windows codepage 949, because reportedly the EUC-KR
charset name is in widespread (mis?)usage in email and on the web for
data which actually uses the extended characters outside the standard
93x94 grid. this could easily be changed if desired.
the principle of this converter for handling the giant bulk of rare
Hangul syllables outside of the standard KS X 1001 93x94 grid is the
same as the GB18030 converter's treatment of non-explicitly-coded
Unicode codepoints: sequences in the extension range are mapped to an
integer index N, and the converter explicitly computes the Nth Hangul
syllable not explicitly encoded in the character map. empirically,
this requires at most 7 passes over the grid. this approach reduces
the table size required for Korean legacy encodings from roughly 44k
to 17k and should have minimal performance impact on real-world text
conversions since the "slow" characters are rare. where it does have
impact, the cost is merely a large constant time factor.
| Rich Felker | 2 | -0/+678 |
| 2013-08-03 | have new timer threads unblock their own SIGTIMER•••unblocking it in the pthread_once init function is not sufficient,
since multiple threads, some of them with the signal blocked, could
already exist before this is called; timers started from such threads
would be non-functional.
| Rich Felker | 1 | -2/+2 |
| 2013-08-03 | add system for resetting TLS to initial values•••this is needed for reused threads in the SIGEV_THREAD timer
notification system, and could be reused elsewhere in the future if
needed, though it should be refactored for such use.
for static linking, __init_tls.c is simply modified to export the TLS
info in a structure with external linkage, rather than using statics.
this perhaps makes the code more clear, since the statics were poorly
named for statics. the new __reset_tls.c is only linked if it is used.
for dynamic linking, the code is in dynlink.c. sharing code with
__copy_tls is not practical since __reset_tls must also re-zero
thread-local bss.
| Rich Felker | 4 | -14/+56 |
| 2013-08-03 | fix multiple bugs in SIGEV_THREAD timers•••1. the thread result field was reused for storing a kernel timer id,
but would be overwritten if the application code exited or cancelled
the thread.
2. low pointer values were used as the indicator that the timer id is
a kernel timer id rather than a thread id. this is not portable, as
mmap may return low pointers on some conditions. instead, use the fact
that pointers must be aligned and kernel timer ids must be
non-negative to map pointers into the negative integer space.
3. signals were not blocked until after the timer thread started, so a
race condition could allow a signal handler to run in the timer thread
when it's not supposed to exist. this is mainly problematic if the
calling thread was the only thread where the signal was unblocked and
the signal handler assumes it runs in that thread.
| Rich Felker | 6 | -22/+36 |
| 2013-08-03 | add some new linux AT_* flags | Rich Felker | 1 | -0/+2 |
| 2013-08-03 | fix faccessat to support AT_EACCESS flag•••this is another case of the kernel syscall failing to support flags
where it needs to, leading to horrible workarounds in userspace. this
time the workaround requires changing uid/gid, and that's not safe to
do in the current process. in the worst case, kernel resource limits
might prevent recovering the original values, and then there would be
no way to safely return. so, use the safe but horribly inefficient
alternative: forking. clone is used instead of fork to suppress
signals from the child.
fortunately this worst-case code is only needed when effective and
real ids mismatch, which mainly happens in suid programs.
| Rich Felker | 1 | -1/+46 |
| 2013-08-03 | collapse euidaccess to a call to faccessat•••it turns out Linux is buggy for faccessat, just like fchmodat: the
kernel does not actually take a flags argument. so we're going to have
to emulate it there.
| Rich Felker | 1 | -9/+1 |
| 2013-08-03 | add prototypes for euidaccess/eaccess | Rich Felker | 1 | -0/+2 |
