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2013-04-26optimize/debloat raise•••use __syscall rather than syscall when failure is not possible or not to be considered. Rich Felker1-2/+2
2013-04-26prevent code from running under a thread id which already gave ESRCHRich Felker1-1/+7
2013-04-26synccall signal handler need not handle dead threads anymore•••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. Rich Felker1-9/+0
2013-04-26fix clobbering of signal mask when creating thread with sched attributes•••this was simply a case of saving the state in the wrong place. Rich Felker1-1/+1
2013-04-26make last thread's pthread_exit give exit(0) a consistent state•••the previous few commits ended up leaving the thread count and signal mask wrong for atexit handlers and stdio cleanup. Rich Felker1-2/+12
2013-04-26use atomic decrement rather than cas in pthread_exit thread count•••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. Rich Felker1-4/+1
2013-04-26add comments on some of the pthread_exit logicRich Felker1-2/+15
2013-04-26always block signals in pthread_exit before decrementing thread count•••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. Rich Felker1-2/+2
2013-04-26remove explicit locking to prevent __synccall setuid during posix_spawn•••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. Rich Felker1-13/+0
2013-04-22remove __STDC_LIMIT_MACROS and __STDC_CONSTANT_MACROS checks in stdint.h•••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. Rich Felker1-8/+0
2013-04-22fix reversed argument order x86_64 sigsetjmp's call to sigprocmask•••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. Rich Felker1-2/+2
2013-04-20comment potentially-confusing use of struct crypt_data typeRich Felker2-1/+10
2013-04-20mention bits headers in another part of copyright fileRich Felker1-1/+1
2013-04-20update copyright yearRich Felker1-2/+2
2013-04-20clarify that bits headers are included as public headersRich Felker1-6/+6
2013-04-20make dynamic linker accept : or \n as path separator•••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. Rich Felker1-8/+8
2013-04-14release notes for 0.9.10Rich Felker1-0/+52
2013-04-10make ifaddrs.h expose sys/socket.h•••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. Rich Felker1-0/+1
2013-04-09getifaddrs: implement proper ipv6 netmasksrofl0r1-2/+11
2013-04-08mbrtowc: do not leave mbstate_t in permanent-fail state after EILSEQ•••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. Rich Felker1-1/+1
2013-04-08implement mbtowc directly, not as a wrapper for mbrtowc•••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. Rich Felker1-5/+39
2013-04-08optimize mbrtowc•••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. Rich Felker1-3/+2
2013-04-08fix out-of-bounds access in UTF-8 decoding•••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... Rich Felker1-1/+1
2013-04-07fix signalfd not to ignore flags•••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. Rich Felker1-1/+12
2013-04-06silence nonsensical warnings in timer_createRich Felker1-2/+2
2013-04-06add support for program_invocation[_short]_name•••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. Rich Felker3-2/+18
2013-04-06fix argument omission in ABI-compat weak_alias for fscanfRich Felker1-1/+1
2013-04-05Add ABI compatability aliases.•••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. Isaac Dunham13-0/+38
2013-04-06fix type error in pthread_create, introduced with pthread_getattr_npRich Felker1-1/+1
2013-04-06getifaddrs: remove unused labelrofl0r1-1/+0
2013-04-05getifaddrs: use if_nameindex to enumerate interfacesrofl0r1-23/+9
2013-04-05getifaddrs: one less indent levelrofl0r1-30/+28
2013-04-05getifaddrs: less mallocrofl0r1-55/+52
2013-04-05include/ifaddrs.h: add prototypes for get/freeifaddrsrofl0r1-0/+3
2013-04-05add getifaddrs•••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. rofl0r2-0/+222
2013-04-05net/if.h: add some missing IFF_ constantsrofl0r1-0/+5
2013-04-04add prototype for dn_skipnameRich Felker1-0/+1