oweals/musl.git
13 years agofix bug whereby getopt_long allowed mismatch in last char of option name
Rich Felker [Wed, 13 Apr 2011 18:52:23 +0000 (14:52 -0400)]
fix bug whereby getopt_long allowed mismatch in last char of option name

13 years agofix typos on RLIM_NLIMITS, remove _GNU_SOURCE test for it
Rich Felker [Wed, 13 Apr 2011 17:22:19 +0000 (13:22 -0400)]
fix typos on RLIM_NLIMITS, remove _GNU_SOURCE test for it

RLIM_* is in the reserved namespace for this header

13 years agofix and cleanup suseconds_t/timeval stuff (broken on 64-bit)
Rich Felker [Wed, 13 Apr 2011 17:16:49 +0000 (13:16 -0400)]
fix and cleanup suseconds_t/timeval stuff (broken on 64-bit)

trash in the upper 32 bits was making the kernel sleep forever in
select on 64-bit systems.

13 years agoimplement getgrouplist (for initgroups), formerly dummied-out v0.7.8
Rich Felker [Wed, 13 Apr 2011 13:39:47 +0000 (09:39 -0400)]
implement getgrouplist (for initgroups), formerly dummied-out

13 years agofix prototypes/signature for setgroups, etc.
Rich Felker [Wed, 13 Apr 2011 13:03:22 +0000 (09:03 -0400)]
fix prototypes/signature for setgroups, etc.

13 years agofix incorrect GNU sighandler_t typedef
Rich Felker [Wed, 13 Apr 2011 12:45:28 +0000 (08:45 -0400)]
fix incorrect GNU sighandler_t typedef

13 years agoimplement memrchr (nonstandard) and optimize strrchr in terms of it
Rich Felker [Wed, 13 Apr 2011 12:36:29 +0000 (08:36 -0400)]
implement memrchr (nonstandard) and optimize strrchr in terms of it

13 years agoadd ptsname_r (nonstandard) and split ptsname (standard) to separate file
Rich Felker [Wed, 13 Apr 2011 12:35:32 +0000 (08:35 -0400)]
add ptsname_r (nonstandard) and split ptsname (standard) to separate file

this eliminates the ugly static buffer in programs that use ptsname_r.

13 years agospeed up threaded fork
Rich Felker [Tue, 12 Apr 2011 21:52:14 +0000 (17:52 -0400)]
speed up threaded fork

after fork, we have a new process and the pid is equal to the tid of
the new main thread. there is no need to make two separate syscalls to
obtain the same number.

13 years agomore changes for upcoming 0.7.8
Rich Felker [Tue, 12 Apr 2011 17:36:22 +0000 (13:36 -0400)]
more changes for upcoming 0.7.8

13 years agooptimize ntohl etc. in terms of bswap functions
Rich Felker [Tue, 12 Apr 2011 17:13:27 +0000 (13:13 -0400)]
optimize ntohl etc. in terms of bswap functions

we can do this without violating the namespace now that they are
macros/inline functions rather than extern functions. the motivation
is that gcc was generating giant, slow, horrible code for the old
functions, and now generates a single byte-swapping instruction.

13 years agomove bswap functions to static inline in byteswap.h
Rich Felker [Tue, 12 Apr 2011 17:04:17 +0000 (13:04 -0400)]
move bswap functions to static inline in byteswap.h

13 years agofix broken bswap_32
Rich Felker [Tue, 12 Apr 2011 16:18:11 +0000 (12:18 -0400)]
fix broken bswap_32

13 years agoutmpx.h is no longer under standards, so expose ut_exit structure
Rich Felker [Tue, 12 Apr 2011 16:03:33 +0000 (12:03 -0400)]
utmpx.h is no longer under standards, so expose ut_exit structure

13 years agoadd some traditional aliases to stat.h
Rich Felker [Tue, 12 Apr 2011 16:01:20 +0000 (12:01 -0400)]
add some traditional aliases to stat.h

13 years agofix printf("%.9g", 1.1) and similar not dropping trailing zeros
Rich Felker [Tue, 12 Apr 2011 15:50:52 +0000 (11:50 -0400)]
fix printf("%.9g", 1.1) and similar not dropping trailing zeros

13 years agoadd missing rlimit macros
Rich Felker [Tue, 12 Apr 2011 15:50:14 +0000 (11:50 -0400)]
add missing rlimit macros

13 years agomore types cleanup
Rich Felker [Mon, 11 Apr 2011 14:48:52 +0000 (10:48 -0400)]
more types cleanup

the basic idea is that the only things in alltypes.h should be types
that either vary from system to system (in practice, not just in
theoretical la-la land - this is the implementation so we choose what
constraints we want to impose on ports) or which are needed by
multiple system headers.

13 years agocleanup types stuff in headers, fix missing u_int*_t in sys/types.h
Rich Felker [Mon, 11 Apr 2011 14:38:00 +0000 (10:38 -0400)]
cleanup types stuff in headers, fix missing u_int*_t in sys/types.h

13 years agofix errno handling in scandir:
Rich Felker [Mon, 11 Apr 2011 05:58:14 +0000 (01:58 -0400)]
fix errno handling in scandir:

1. saved errno was not being restored, illegally clearing errno to 0.
2. no need to backup and save errno around free; it will not touch
except perhaps when the program has already invoked UB...

13 years agofix fputwc return value
Rich Felker [Mon, 11 Apr 2011 05:52:23 +0000 (01:52 -0400)]
fix fputwc return value

13 years agoremove ugly warning-suppression hack from crypt - this invokes UB!
Rich Felker [Mon, 11 Apr 2011 05:50:26 +0000 (01:50 -0400)]
remove ugly warning-suppression hack from crypt - this invokes UB!

13 years agoupdate README since we now DO have a mailing list
Rich Felker [Mon, 11 Apr 2011 04:10:26 +0000 (00:10 -0400)]
update README since we now DO have a mailing list

13 years agoadd some ugly legacy type names in sys/types.h (u_char etc.)
Rich Felker [Mon, 11 Apr 2011 02:47:43 +0000 (22:47 -0400)]
add some ugly legacy type names in sys/types.h (u_char etc.)

13 years agoadd legacy BSD-style timer*() macros in sys/time.h
Rich Felker [Mon, 11 Apr 2011 02:46:46 +0000 (22:46 -0400)]
add legacy BSD-style timer*() macros in sys/time.h

13 years agoadd missing UTIME_* macros in sys/stat.h
Rich Felker [Sun, 10 Apr 2011 22:32:59 +0000 (18:32 -0400)]
add missing UTIME_* macros in sys/stat.h

13 years agoadd missing float.h macros
Rich Felker [Sun, 10 Apr 2011 22:27:47 +0000 (18:27 -0400)]
add missing float.h macros

actually FLT_ROUNDS needs to expand to a static inline function that
obtains the current rounding mode and returns it, but that will be
added later with fenv.h stuff.

13 years agorun pthread tsd destructors when a timer thread pretends to exit
Rich Felker [Sat, 9 Apr 2011 06:26:55 +0000 (02:26 -0400)]
run pthread tsd destructors when a timer thread pretends to exit

13 years agogreatly improve SIGEV_THREAD timers
Rich Felker [Sat, 9 Apr 2011 06:23:33 +0000 (02:23 -0400)]
greatly improve SIGEV_THREAD timers

calling pthread_exit from, or pthread_cancel on, the timer callback
thread will no longer destroy the timer.

13 years agoprepare notes for 0.7.8 release
Rich Felker [Sat, 9 Apr 2011 05:32:38 +0000 (01:32 -0400)]
prepare notes for 0.7.8 release

13 years agowork around a nasty bug in linux readv syscall
Rich Felker [Sat, 9 Apr 2011 05:17:55 +0000 (01:17 -0400)]
work around a nasty bug in linux readv syscall

according to posix, readv "shall be equivalent to read(), except..."
that it places the data into the buffers specified by the iov array.
however on linux, when reading from a terminal, each iov element
behaves almost like a separate read. this means that if the first iov
exactly satisfied the request (e.g. a length-one read of '\n') and the
second iov is nonzero length, the syscall will block again after
getting the blank line from the terminal until another line is read.
simply put, entering a single blank line becomes impossible.

the solution, fortunately, is simple. whenever the buffer size is
nonzero, reduce the length of the requested read by one byte and let
the last byte go through the buffer. this way, readv will already be
in the second (and last) iov, and won't re-block on the second iov.

13 years agobetter fix sysconf pthread stack min
Rich Felker [Fri, 8 Apr 2011 16:16:24 +0000 (12:16 -0400)]
better fix sysconf pthread stack min

13 years agoconsistency with pthread stack min in limits.h
Rich Felker [Fri, 8 Apr 2011 16:15:37 +0000 (12:15 -0400)]
consistency with pthread stack min in limits.h

13 years agofix broken sigsetjmp on x86_64
Rich Felker [Fri, 8 Apr 2011 15:56:52 +0000 (11:56 -0400)]
fix broken sigsetjmp on x86_64

13 years agoworkaround broken msghdr struct on 64bit linux
Rich Felker [Fri, 8 Apr 2011 13:24:19 +0000 (09:24 -0400)]
workaround broken msghdr struct on 64bit linux

POSIX clearly specifies the type of msg_iovlen and msg_controllen, and
Linux ignores it and makes them both size_t instead. to work around
this we add padding (instead of just using the wrong types like glibc
does), but we also need to patch-up the struct before passing it to
the kernel in case the caller did not zero-fill it.

if i could trust the kernel to just ignore the upper 32 bits, this
would not be necessary, but i don't think it will ignore them...

13 years agofix ipv6 address printing: 2001 appeared as 201, etc.
Rich Felker [Fri, 8 Apr 2011 13:21:51 +0000 (09:21 -0400)]
fix ipv6 address printing: 2001 appeared as 201, etc.

13 years agofix broken dns response parsing code that made most ipv6 lookups fail
Rich Felker [Fri, 8 Apr 2011 12:49:28 +0000 (08:49 -0400)]
fix broken dns response parsing code that made most ipv6 lookups fail

13 years agoreturn the requested string as the "canonical name" for numeric addresses
Rich Felker [Fri, 8 Apr 2011 12:14:28 +0000 (08:14 -0400)]
return the requested string as the "canonical name" for numeric addresses

previously NULL was returned in ai_canonname, resulting in crashes in
some callers. this behavior was incorrect. note however that the new
behavior differs from glibc, which performs reverse dns lookups. POSIX
is very clear that a reverse DNS lookup must not be performed for
numeric addresses.

13 years agofix uninitialized variables in dns lookup code
Rich Felker [Fri, 8 Apr 2011 03:18:12 +0000 (23:18 -0400)]
fix uninitialized variables in dns lookup code

13 years agofix bug in TRE found by clang (typo && instead of &)
Rich Felker [Fri, 8 Apr 2011 03:13:47 +0000 (23:13 -0400)]
fix bug in TRE found by clang (typo && instead of &)

13 years agofix misplaced *'s in string functions (harmless)
Rich Felker [Thu, 7 Apr 2011 20:19:30 +0000 (16:19 -0400)]
fix misplaced *'s in string functions (harmless)

13 years agofix broken unsigned comparison in wcstoumax
Rich Felker [Thu, 7 Apr 2011 20:13:47 +0000 (16:13 -0400)]
fix broken unsigned comparison in wcstoumax

13 years agofix breakage due to converting a return type to size_t in iconv...
Rich Felker [Thu, 7 Apr 2011 20:10:44 +0000 (16:10 -0400)]
fix breakage due to converting a return type to size_t in iconv...

13 years agofixed crash in new rsyscall (failure to set sa_flags for signal handler)
Rich Felker [Thu, 7 Apr 2011 00:43:39 +0000 (20:43 -0400)]
fixed crash in new rsyscall (failure to set sa_flags for signal handler)

13 years agoconsistency: change all remaining syscalls to use SYS_ rather than __NR_ prefix
Rich Felker [Thu, 7 Apr 2011 00:32:53 +0000 (20:32 -0400)]
consistency: change all remaining syscalls to use SYS_ rather than __NR_ prefix

13 years agomove rsyscall out of pthread_create module
Rich Felker [Thu, 7 Apr 2011 00:27:07 +0000 (20:27 -0400)]
move rsyscall out of pthread_create module

this is something of a tradeoff, as now set*id() functions, rather
than pthread_create, are what pull in the code overhead for dealing
with linux's refusal to implement proper POSIX thread-vs-process
semantics. my motivations are:

1. it's cleaner this way, especially cleaner to optimize out the
rsyscall locking overhead from pthread_create when it's not needed.
2. it's expected that only a tiny number of core system programs will
ever use set*id() functions, whereas many programs may want to use
threads, and making thread overhead tiny is an incentive for "light"
programs to try threads.

13 years agopthread exit stuff: don't bother setting errno when we won't check it.
Rich Felker [Wed, 6 Apr 2011 23:47:50 +0000 (19:47 -0400)]
pthread exit stuff: don't bother setting errno when we won't check it.

13 years agofix rsyscall handler: must not clobber errno from signal context
Rich Felker [Wed, 6 Apr 2011 23:46:46 +0000 (19:46 -0400)]
fix rsyscall handler: must not clobber errno from signal context

13 years agofix typo in sys/msg.h
Rich Felker [Wed, 6 Apr 2011 21:50:38 +0000 (17:50 -0400)]
fix typo in sys/msg.h

13 years agoadd startup abi functions, dummy for now. eventually needed for c++ support.
Rich Felker [Wed, 6 Apr 2011 20:40:19 +0000 (16:40 -0400)]
add startup abi functions, dummy for now. eventually needed for c++ support.

13 years agoadd _res (__res_state()) dummy
Rich Felker [Wed, 6 Apr 2011 19:47:26 +0000 (15:47 -0400)]
add _res (__res_state()) dummy

13 years agoadd IN_LOOPBACKNET constant (nonstandard but in reserved namespace)
Rich Felker [Wed, 6 Apr 2011 19:44:39 +0000 (15:44 -0400)]
add IN_LOOPBACKNET constant (nonstandard but in reserved namespace)

13 years agodocument more changes for 0.7.7 v0.7.7
Rich Felker [Wed, 6 Apr 2011 18:46:37 +0000 (14:46 -0400)]
document more changes for 0.7.7

13 years agofix prototype for strsep
Rich Felker [Wed, 6 Apr 2011 18:28:29 +0000 (14:28 -0400)]
fix prototype for strsep

13 years agofix completely bogus loop condition in getmntent_r
Rich Felker [Wed, 6 Apr 2011 16:35:05 +0000 (12:35 -0400)]
fix completely bogus loop condition in getmntent_r

somehow this worked on my simple fstab, but horribly broke in general,
leading to use of uninitialized offset array and crashes.

13 years agomajor semaphore improvements (performance and correctness)
Rich Felker [Wed, 6 Apr 2011 16:24:34 +0000 (12:24 -0400)]
major semaphore improvements (performance and correctness)

1. make sem_[timed]wait interruptible by signals, per POSIX
2. keep a waiter count in order to avoid unnecessary futex wake syscalls

13 years agofix signal-based timers with null sigevent argument
Rich Felker [Wed, 6 Apr 2011 13:26:41 +0000 (09:26 -0400)]
fix signal-based timers with null sigevent argument

since timer_create is no longer allocating a structure for the timer_t
and simply using the kernel timer id, it was impossible to specify the
timer_t as the argument to the signal handler. the solution is to pass
the null sigevent pointer on to the kernel, rather than filling it in
userspace, so that the kernel does the right thing. however, that
precludes the clever timerid-versus-threadid encoding we were doing.

instead, just assume timerids are below 1M and thread pointers are
above 1M. (in perspective: timerids are sequentially allocated and
seem limited to 32k, and thread pointers are at roughly 3G.)

13 years agofix incorrect (and conflicting on LP64 archs) types for sysv ipc msgq functions
Rich Felker [Wed, 6 Apr 2011 04:02:20 +0000 (00:02 -0400)]
fix incorrect (and conflicting on LP64 archs) types for sysv ipc msgq functions

13 years agofix (hopefully) statvfs breakage on x86_64 that resulted from fixing i386...
Rich Felker [Wed, 6 Apr 2011 03:58:36 +0000 (23:58 -0400)]
fix (hopefully) statvfs breakage on x86_64 that resulted from fixing i386...

13 years agodocument more changes
Rich Felker [Tue, 5 Apr 2011 22:58:47 +0000 (18:58 -0400)]
document more changes

13 years agonew framework to inhibit thread cancellation when needed
Rich Felker [Tue, 5 Apr 2011 22:00:28 +0000 (18:00 -0400)]
new framework to inhibit thread cancellation when needed

with these small changes, libc functions which need to call functions
which are cancellation points, but which themselves must not be
cancellation points, can use the CANCELPT_INHIBIT and CANCELPT_RESUME
macros to temporarily inhibit all cancellation.

13 years agoadd ip6 pktinfo stuff for x86_64
Rich Felker [Tue, 5 Apr 2011 21:27:28 +0000 (17:27 -0400)]
add ip6 pktinfo stuff for x86_64

these defs should probably all be moved out of bits and unified...

13 years agoadd sysv ipc message queues (completely untested)
Rich Felker [Tue, 5 Apr 2011 20:33:55 +0000 (16:33 -0400)]
add sysv ipc message queues (completely untested)

13 years agogetopt.h is a GNU-getopt-specific header. always expose GNU functions.
Rich Felker [Tue, 5 Apr 2011 19:45:24 +0000 (15:45 -0400)]
getopt.h is a GNU-getopt-specific header. always expose GNU functions.

13 years agoadd sysexits.h legacy header
Rich Felker [Tue, 5 Apr 2011 19:40:36 +0000 (15:40 -0400)]
add sysexits.h legacy header

13 years agoimplement the adjtime and adjtimex functions (nonstandard)
Rich Felker [Tue, 5 Apr 2011 19:38:20 +0000 (15:38 -0400)]
implement the adjtime and adjtimex functions (nonstandard)

13 years agoadd getmntent_r interface (all of mntent is nonstandard anyway)
Rich Felker [Tue, 5 Apr 2011 18:11:14 +0000 (14:11 -0400)]
add getmntent_r interface (all of mntent is nonstandard anyway)

13 years agoadd some missing ipv6 stuff
Rich Felker [Tue, 5 Apr 2011 18:05:11 +0000 (14:05 -0400)]
add some missing ipv6 stuff

13 years agoimplement if_indextoname and if_nametoindex functions
Rich Felker [Tue, 5 Apr 2011 17:20:08 +0000 (13:20 -0400)]
implement if_indextoname and if_nametoindex functions

13 years agoadd (nonstandard) cfmakeraw function
Rich Felker [Tue, 5 Apr 2011 16:35:09 +0000 (12:35 -0400)]
add (nonstandard) cfmakeraw function

13 years agoadd pivot_root syscall wrapper
Rich Felker [Tue, 5 Apr 2011 16:32:10 +0000 (12:32 -0400)]
add pivot_root syscall wrapper

13 years agoadd more legacy functions: setlinebuf and setbuffer
Rich Felker [Tue, 5 Apr 2011 16:25:31 +0000 (12:25 -0400)]
add more legacy functions: setlinebuf and setbuffer

13 years agoalternate name for syslog.h
Rich Felker [Tue, 5 Apr 2011 16:13:54 +0000 (12:13 -0400)]
alternate name for syslog.h

13 years agouncomment IP_PKTINFO
Rich Felker [Tue, 5 Apr 2011 16:07:42 +0000 (12:07 -0400)]
uncomment IP_PKTINFO

this was a hack leftover from testing before the initial
check-in to git.

13 years agosupport the nonstandard err.h interfaces
Rich Felker [Tue, 5 Apr 2011 15:16:49 +0000 (11:16 -0400)]
support the nonstandard err.h interfaces

note that unlike the originals, these do not print the program
name/argv[0] because we have not saved it anywhere. this could be
changed in __libc_start_main if desired.

13 years agorelease notes for next bugfix release
Rich Felker [Tue, 5 Apr 2011 14:28:08 +0000 (10:28 -0400)]
release notes for next bugfix release

13 years agofix misaligned read on early string termination in strchr
Rich Felker [Tue, 5 Apr 2011 13:27:41 +0000 (09:27 -0400)]
fix misaligned read on early string termination in strchr

this could actually cause rare crashes in the case where a short
string is located at the end of a page and the following page is not
readable, and in fact this was seen in gcc compiling certain files.

13 years agofix overflow in printf %N$ argument handling
Rich Felker [Tue, 5 Apr 2011 13:24:03 +0000 (09:24 -0400)]
fix overflow in printf %N$ argument handling

13 years agofix various floating point rounding and formatting errors in *printf
Rich Felker [Tue, 5 Apr 2011 13:16:40 +0000 (09:16 -0400)]
fix various floating point rounding and formatting errors in *printf

13 years agorelease notes for 0.7.6 bugfix release v0.7.6
Rich Felker [Mon, 4 Apr 2011 22:00:02 +0000 (18:00 -0400)]
release notes for 0.7.6 bugfix release

13 years agofix rare but nasty under-allocation bug in malloc with large requests
Rich Felker [Mon, 4 Apr 2011 21:26:41 +0000 (17:26 -0400)]
fix rare but nasty under-allocation bug in malloc with large requests

the bug appeared only with requests roughly 2*sizeof(size_t) to
4*sizeof(size_t) bytes smaller than a multiple of the page size, and
only for requests large enough to be serviced by mmap instead of the
normal heap. it was only ever observed on 64-bit machines but
presumably could also affect 32-bit (albeit with a smaller window of
opportunity).

13 years agosimplify vdprintf implementation greatly based on recent vfprintf changes
Rich Felker [Mon, 4 Apr 2011 20:30:39 +0000 (16:30 -0400)]
simplify vdprintf implementation greatly based on recent vfprintf changes

since vfprintf will provide a temporary buffer in the case where the
target FILE has a zero buffer size, don't bother setting up a real
buffer for vdprintf. this also allows us to skip the call to fflush
since we know everything will be written out before vfprintf returns.

13 years agouse a local temp buffer for unbuffered streams in vfprintf
Rich Felker [Mon, 4 Apr 2011 20:24:49 +0000 (16:24 -0400)]
use a local temp buffer for unbuffered streams in vfprintf

this change makes it so most calls to fprintf(stderr, ...) will result
in a single writev syscall, as opposed to roughly 2*N syscalls (and
possibly more) where N is the number of format specifiers. in
principle we could use a much larger buffer, but it's best not to
increase the stack requirements too much. most messages are under 80
chars.

13 years agofix nl_langinfo to actually use the existing, correct internal version
Rich Felker [Sun, 3 Apr 2011 23:51:14 +0000 (19:51 -0400)]
fix nl_langinfo to actually use the existing, correct internal version

13 years agomake ualarm actually work (obsolete function removed from SUS)
Rich Felker [Sun, 3 Apr 2011 23:18:43 +0000 (19:18 -0400)]
make ualarm actually work (obsolete function removed from SUS)

13 years agofix various bugs in strtold:
Rich Felker [Sun, 3 Apr 2011 22:44:37 +0000 (18:44 -0400)]
fix various bugs in strtold:

0e10000000000000000000000000000000 was setting ERANGE

exponent char e/p was considered part of the match even if not
followed by a valid decimal value

"1e +10" was parsed as "1e+10"

hex digits were misinterpreted as 0..5 instead of 10..15

13 years agofix serious bug in strchr - char signedness
Rich Felker [Sun, 3 Apr 2011 22:16:11 +0000 (18:16 -0400)]
fix serious bug in strchr - char signedness

search for bytes with high bit set was giving (potentially dangerous)
wrong results. i've tested, cleaned up, and hopefully sped up this
function now.

13 years agoprototype getdtablesize (nonstandard function)
Rich Felker [Sun, 3 Apr 2011 22:15:36 +0000 (18:15 -0400)]
prototype getdtablesize (nonstandard function)

13 years agoadd setresuid/setresgid functions (nonstandard)
Rich Felker [Sun, 3 Apr 2011 20:20:57 +0000 (16:20 -0400)]
add setresuid/setresgid functions (nonstandard)

13 years agopthread_create need not set errno
Rich Felker [Sun, 3 Apr 2011 20:15:15 +0000 (16:15 -0400)]
pthread_create need not set errno

13 years agofix statvfs syscalls (missing size argument)
Rich Felker [Sun, 3 Apr 2011 19:42:31 +0000 (15:42 -0400)]
fix statvfs syscalls (missing size argument)

13 years agoblock all signals during rsyscall
Rich Felker [Sun, 3 Apr 2011 17:15:42 +0000 (13:15 -0400)]
block all signals during rsyscall

otherwise a signal handler could see an inconsistent and nonconformant
program state where different threads have different uids/gids.

13 years agofix race condition in rsyscall handler
Rich Felker [Sun, 3 Apr 2011 17:03:18 +0000 (13:03 -0400)]
fix race condition in rsyscall handler

the problem: there is a (single-instruction) race condition window
between a thread flagging itself dead and decrementing itself from the
thread count. if it receives the rsyscall signal at this exact moment,
the rsyscall caller will never succeed in signalling enough flags to
succeed, and will deadlock forever. in previous versions of musl, the
about-to-terminate thread masked all signals prior to decrementing
the thread count, but this cost a whole syscall just to account for
extremely rare races.

the solution is a huge hack: rather than blocking in the signal
handler if the thread is dead, modify the signal mask of the saved
context and return in order to prevent further signal handling by the
dead thread. this allows the dead thread to continue decrementing the
thread count (if it had not yet done so) and exiting, even while the
live part of the program blocks for rsyscall.

13 years agodon't trust siginfo in rsyscall handler
Rich Felker [Sun, 3 Apr 2011 16:20:51 +0000 (12:20 -0400)]
don't trust siginfo in rsyscall handler

for some inexplicable reason, linux allows the sender of realtime
signals to spoof its identity. permission checks for sending signals
should limit the impact to same-user processes, but just to be safe,
we avoid trusting the siginfo structure and instead simply examine the
program state to see if we're in the middle of a legitimate rsyscall.

13 years agotimer threads should sleep and stay asleep... a long time
Rich Felker [Sun, 3 Apr 2011 16:10:24 +0000 (12:10 -0400)]
timer threads should sleep and stay asleep... a long time

13 years agorevert to deleting kernel-level timer from cancellation handler
Rich Felker [Sun, 3 Apr 2011 16:08:34 +0000 (12:08 -0400)]
revert to deleting kernel-level timer from cancellation handler

this is necessary in order to avoid breaking timer_getoverrun in the
last run of the timer event handler, if it has not yet finished.

13 years agosimplify calling of timer signal handler
Rich Felker [Sun, 3 Apr 2011 16:03:58 +0000 (12:03 -0400)]
simplify calling of timer signal handler

13 years agod_fileno alias for d_ino in dirent
Rich Felker [Sun, 3 Apr 2011 14:24:59 +0000 (10:24 -0400)]
d_fileno alias for d_ino in dirent

this is nonstandard but since POSIX reserved d_ prefix in dirent.h we
might as well define it unconditionally. some programs depend on it.

13 years agosimplify pthread tsd key handling
Rich Felker [Sun, 3 Apr 2011 06:40:18 +0000 (02:40 -0400)]
simplify pthread tsd key handling

13 years agoomit pthread tsd dtor code if tsd is not used
Rich Felker [Sun, 3 Apr 2011 06:33:50 +0000 (02:33 -0400)]
omit pthread tsd dtor code if tsd is not used