summaryrefslogtreecommitdiff
AgeCommit message (Collapse)AuthorLines
2013-04-26transition to using functions for internal signal blocking/restoringRich Felker-12/+57
there are several reasons for this change. one is getting rid of the repetition of the syscall signature all over the place. another is sharing the constant masks without costly GOT accesses in PIC. the main motivation, however, is accurately representing whether we want to block signals that might be handled by the application, or all signals.
2013-04-26optimize/debloat raiseRich Felker-2/+2
use __syscall rather than syscall when failure is not possible or not to be considered.
2013-04-26prevent code from running under a thread id which already gave ESRCHRich Felker-1/+7
2013-04-26synccall signal handler need not handle dead threads anymoreRich Felker-9/+0
they have already blocked signals before decrementing the thread count, so the code being removed is unreachable in the case where the thread is no longer counted.
2013-04-26fix clobbering of signal mask when creating thread with sched attributesRich Felker-1/+1
this was simply a case of saving the state in the wrong place.
2013-04-26make last thread's pthread_exit give exit(0) a consistent stateRich Felker-3/+13
the previous few commits ended up leaving the thread count and signal mask wrong for atexit handlers and stdio cleanup.
2013-04-26use atomic decrement rather than cas in pthread_exit thread countRich Felker-4/+1
now that blocking signals prevents any application code from running while the last thread is exiting, the cas logic is no longer needed to prevent decrementing below zero.
2013-04-26add comments on some of the pthread_exit logicRich Felker-2/+15
2013-04-26always block signals in pthread_exit before decrementing thread countRich Felker-2/+2
the thread count (1+libc.threads_minus_1) must always be greater than or equal to the number of threads which could have application code running, even in an async-signal-safe sense. there is at least one dangerous race condition if this invariant fails to hold: dlopen could allocate too little TLS for existing threads, and a signal handler running in the exiting thread could claim the allocated TLS for itself (via __tls_get_addr), leaving too little for the other threads it was allocated for and thereby causing out-of-bounds access. there may be other situations where it's dangerous for the thread count to be too low, particularly in the case where only one thread should be left, in which case locking may be omitted. however, all such code paths seem to arise from undefined behavior, since async-signal-unsafe functions are not permitted to be called from a signal handler that interrupts pthread_exit (which is itself async-signal-unsafe). this change may also simplify logic in __synccall and improve the chances of making __synccall async-signal-safe.
2013-04-26remove explicit locking to prevent __synccall setuid during posix_spawnRich Felker-13/+0
for the duration of the vm-sharing clone used by posix_spawn, all signals are blocked in the parent process, including implementation-internal signals. since __synccall cannot do anything until successfully signaling all threads, the fact that signals are blocked automatically yields the necessary safety. aside from debloating and general simplification, part of the motivation for removing the explicit lock is to simplify the synchronization logic of __synccall in hopes that it can be made async-signal-safe, which is needed to make setuid and setgid, which depend on __synccall, conform to the standard. whether this will be possible remains to be seen.
2013-04-22remove __STDC_LIMIT_MACROS and __STDC_CONSTANT_MACROS checks in stdint.hRich Felker-8/+0
C++11, the first C++ with stdint.h, requires the previously protected macros to be exposed unconditionally by stdint.h. apparently these checks were an early attempt by the C committee to guess what the C++ committee would want, and they guessed wrong.
2013-04-22fix reversed argument order x86_64 sigsetjmp's call to sigprocmaskRich Felker-2/+2
this caused sigsetjmp not to save the signal mask but instead to clobber it with whatever happened to be in the sigjmb_buf prior to the call.
2013-04-20comment potentially-confusing use of struct crypt_data typeRich Felker-1/+10
2013-04-20mention bits headers in another part of copyright fileRich Felker-1/+1
2013-04-20update copyright yearRich Felker-2/+2
2013-04-20clarify that bits headers are included as public headersRich Felker-6/+6
2013-04-20make dynamic linker accept : or \n as path separatorRich Felker-8/+8
this allows /etc/ld-musl-$(ARCH).path to contain one path per line, which is much more convenient for users than the :-delimited format, which was a source of repeated and unnecessary confusion. for simplicity, \n is also accepted in environment variables, though it should probably not be used there. at the same time, issues with overly long paths invoking UB or getting truncated have been fixed. such issues should not have arisen with the environment (which is size-limited) but could have been generated by a path file larger than 2**31 bytes in length.
2013-04-14release notes for 0.9.10v0.9.10Rich Felker-0/+52
2013-04-10make ifaddrs.h expose sys/socket.hRich Felker-0/+1
the getifaddrs interface seems to have been invented by glibc, and they expose socket.h, so for us not to do so is just gratuitous incompatibility with the interface we're mimicing.
2013-04-09getifaddrs: implement proper ipv6 netmasksrofl0r-2/+11
2013-04-08mbrtowc: do not leave mbstate_t in permanent-fail state after EILSEQRich Felker-1/+1
the standard is clear that the old behavior is conforming: "In this case, [EILSEQ] shall be stored in errno and the conversion state is undefined." however, the specification of mbrtowc has one peculiarity when the source argument is a null pointer: in this case, it's required to behave as mbrtowc(NULL, "", 1, ps). no motivation is provided for this requirement, but the natural one that comes to mind is that the intent is to reset the mbstate_t object. for stateful encodings, such behavior is actually specified: "If the corresponding wide character is the null wide character, the resulting state described shall be the initial conversion state." but in the case of UTF-8 where the mbstate_t object contains a partially-decoded character rather than a shift state, a subsequent '\0' byte indicates that the previous partial character is incomplete and thus an illegal sequence. naturally, applications using their own mbstate_t object should clear it themselves after an error, but the standard presently provides no way to clear the builtin mbstate_t object used when the ps argument is a null pointer. I suspect this issue may be addressed in the future by specifying that a null source argument resets the state, as this seems to have been the intent all along. for what it's worth, this change also slightly reduces code size.
2013-04-08implement mbtowc directly, not as a wrapper for mbrtowcRich Felker-5/+39
the interface contract for mbtowc admits a much faster implementation than mbrtowc can achieve; wrapping mbrtowc with an extra call frame only made the situation worse. since the regex implementation uses mbtowc already, this change should improve regex performance too. it may be possible to improve performance in other places internally by switching from mbrtowc to mbtowc.
2013-04-08optimize mbrtowcRich Felker-3/+2
this simple change, in my measurements, makes about a 7% performance improvement. at first glance this change would seem like a compiler-specific hack, since the modified code is not even used. however, I suspect the reason is that I'm eliminating a second path into the main body of the code, allowing the compiler more flexibility to optimize the normal (hot) path into the main body. so even if it weren't for the measurable (and quite notable) difference in performance, I think the change makes sense.
2013-04-08fix out-of-bounds access in UTF-8 decodingRich Felker-1/+1
SA and SB are used as the lowest and highest valid starter bytes, but the value of SB was one-past the last valid starter. this caused access past the end of the state table when the illegal byte '\xf5' was encountered in a starter position. the error did not show up in full-character decoding tests, since the bogus state read from just past the table was unlikely to admit any continuation bytes as valid, but would have shown up had we tested feeding '\xf5' to the byte-at-a-time decoding in mbrtowc: it would cause the funtion to wrongly return -2 rather than -1. I may eventually go back and remove all references to SA and SB, replacing them with the values; this would make the code more transparent, I think. the original motivation for using macros was to allow misguided users of the code to redefine them for the purpose of enlarging the set of accepted sequences past the end of Unicode...
2013-04-07fix signalfd not to ignore flagsRich Felker-1/+12
also include fallback code for broken kernels that don't support the flags. as usual, the fallback has a race condition that can leak file descriptors.
2013-04-06silence nonsensical warnings in timer_createRich Felker-2/+2
2013-04-06add support for program_invocation[_short]_nameRich Felker-2/+18
this is a bit ugly, and the motivation for supporting it is questionable. however the main factors were: 1. it will be useful to have this for certain internal purposes anyway -- things like syslog. 2. applications can just save argv[0] in main, but it's hard to fix non-portable library code that's depending on being able to get the invocation name without the main application's help.
2013-04-06fix argument omission in ABI-compat weak_alias for fscanfRich Felker-1/+1
2013-04-05Add ABI compatability aliases.Isaac Dunham-0/+38
GNU used several extensions that were incompatible with C99 and POSIX, so they used alternate names for the standard functions. The result is that we need these to run standards-conformant programs that were linked with glibc.
2013-04-06fix type error in pthread_create, introduced with pthread_getattr_npRich Felker-1/+1
2013-04-06getifaddrs: remove unused labelrofl0r-1/+0
2013-04-05getifaddrs: use if_nameindex to enumerate interfacesrofl0r-23/+9
2013-04-05getifaddrs: one less indent levelrofl0r-30/+28
2013-04-05getifaddrs: less mallocrofl0r-55/+52
2013-04-05include/ifaddrs.h: add prototypes for get/freeifaddrsrofl0r-0/+3
2013-04-05add getifaddrsrofl0r-0/+222
supports ipv4 and ipv6, but not the "extended" usage where usage statistics and other info are assigned to ifa_data members of duplicate entries with AF_PACKET family.
2013-04-05net/if.h: add some missing IFF_ constantsrofl0r-0/+5
2013-04-04add prototype for dn_skipnameRich Felker-0/+1
2013-04-04implement dn_skipname (legacy resolver function)Rich Felker-0/+12
2013-04-05add arpa/tftp.hrofl0r-0/+31
2013-04-04fix type issues in stdint.h so underlying types of 64-bit types match ABIRich Felker-8/+33
2013-04-04eliminate bits/wchar.hRich Felker-26/+15
the preprocessor can reliably determine the signedness of wchar_t. L'\0' is used for 0 in the expressions so that, if the underlying type of wchar_t is long rather than int, the promoted type of the expression will match the type of wchar_t.
2013-04-04eliminate gcc dependency for testing char signedness in limits.hRich Felker-1/+1
2013-04-04add put*ent functions for passwd/group files and similar for shadowRich Felker-0/+36
since shadow does not yet support enumeration (getspent), the corresponding FILE-based get and put versions are also subbed out for now. this is partly out of laziness and partly because it's not clear how they should work in the presence of TCB shadow files. the stubs should make it possible to compile some software that expects them to exist, but such software still may not work properly.
2013-04-04cleanup wcstombsRich Felker-12/+1
remove redundant headers and comments; this file is completely trivial now. also, avoid temp var.
2013-04-04cleanup mbstowcs wrapperRich Felker-10/+0
remove unneeded headers. this file is utterly trivial now and there's no sense in having a comment to state that it's in the public domain.
2013-04-04minor optimization to mbstowcsRich Felker-2/+1
there is no need to zero-fill an mbstate_t object in the caller; mbsrtowcs will automatically treat a null pointer as the initial state.
2013-04-04fix incorrect range checks in wcsrtombsRich Felker-3/+3
negative values of wchar_t need to be treated in the non-ASCII case so that they can properly generate EILSEQ rather than getting truncated to 8bit values and stored in the output.
2013-04-04overhaul mbsrtowcsRich Felker-69/+64
these changes fix at least two bugs: - misaligned access to the input as uint32_t for vectorized ASCII test - incorrect src pointer after stopping on EILSEQ in addition, the text of the standard makes it unclear whether the mbstate_t object is to be modified when the destination pointer is null; previously it was cleared either way; now, it's only cleared when the destination is non-null. this change may need revisiting, but it should not affect most applications, since calling mbsrtowcs with non-zero state can only happen when the head of the string was already processed with mbrtowc. finally, these changes shave about 20% size off the function and seem to improve performance by 1-5%.
2013-04-02re-add useconds_trofl0r-0/+8
this type was removed back in 5243e5f1606a9c6fcf01414e , because it was removed from the XSI specs. however some apps use it. since it's in the POSIX reserved namespace, we can expose it unconditionally.