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2019-02-15always block signals for starting new threads, refactor start argsRich Felker-1/+0
whether signals need to be blocked at thread start, and whether unblocking is necessary in the entry point function, has historically depended on intricacies of the cancellation design and on whether there are scheduling operations to perform on the new thread before its successful creation can be committed. future changes to track an AS-safe list of live threads will require signals to be blocked whenever changes are made to the list, so ... prior to commits b8742f32602add243ee2ce74d804015463726899 and 40bae2d32fd6f3ffea437fa745ad38a1fe77b27e, a signal mask for the entry function to restore was part of the pthread structure. it was removed to trim down the size of the structure, which both saved a small amount of stack space and improved code generation on archs where small immediate displacements are less costly than arbitrary ones, by limiting the range of offsets between the base of the thread structure, its members, and the thread pointer. these commits moved the saved mask to a special structure used only when special scheduling was needed, in which case the pthread_create caller and new thread had to synchronize with each other and could use this memory to pass a mask. this commit partially reverts the above two commits, but instead of putting the mask back in the pthread structure, it moves all "start argument" members out of the pthread structure, trimming it down further, and puts them in a separate structure passed on the new thread's stack. the code path for explicit scheduling of the new thread is also changed to synchronize with the calling thread in such a way to avoid spurious futex wakes.
2019-02-15for SIGEV_THREAD timer threads, replace signal handler with sigwaitinfoRich Felker-21/+16
this eliminates some ugly hacks that were repurposing the start function and start argument fields in the pthread structure for timer use, and the need to longjmp out of a signal handler.
2019-01-21fix call to __pthread_tsd_run_dtors with too many argumentsRich Felker-1/+1
commit a6054e3c94aa0491d7366e4b05ae0d73f661bfe2 removed the argument, making it a constraint violation to pass one. caught by cparser/firm; other compilers seem to ignore it.
2018-10-22don't omit setting errno in internal __map_file functionRich Felker-2/+2
a caller needs the reason for open (or fstat, albeit unlikely) failure if it's going to make decisions about continuing a path search or similar.
2018-09-15always reset DST rules during tzsetBenjamin Peterson-1/+2
do_tzset() did't always reset the DST transition rules r0 and r1. That means the rules from older TZ settings could leak into newer ones.
2018-09-12split internal lock API out of libc.h, creating lock.hRich Felker-0/+1
this further reduces the number of source files which need to include libc.h and thereby be potentially exposed to libc global state and internals. this will also facilitate further improvements like adding an inline fast-path, if we want to do so later.
2018-09-12reduce spurious inclusion of libc.hRich Felker-8/+1
libc.h was intended to be a header for access to global libc state and related interfaces, but ended up included all over the place because it was the way to get the weak_alias macro. most of the inclusions removed here are places where weak_alias was needed. a few were recently introduced for hidden. some go all the way back to when libc.h defined CANCELPT_BEGIN and _END, and all (wrongly implemented) cancellation points had to include it. remaining spurious users are mostly callers of the LOCK/UNLOCK macros and files that use the LFS64 macro to define the awful *64 aliases. in a few places, new inclusion of libc.h is added because several internal headers no longer implicitly include libc.h. declarations for __lockfile and __unlockfile are moved from libc.h to stdio_impl.h so that the latter does not need libc.h. putting them in libc.h made no sense at all, since the macros in stdio_impl.h are needed to use them correctly anyway.
2018-09-12move declaration and apply hidden visibility to __utc stringRich Felker-4/+1
2018-09-12remove or make static various unused __-prefixed symbolsRich Felker-1/+1
2018-09-12apply hidden visibility to internal time[zone] implementation functionsRich Felker-8/+8
2018-09-12overhaul internally-public declarations using wrapper headersRich Felker-23/+1
commits leading up to this one have moved the vast majority of libc-internal interface declarations to appropriate internal headers, allowing them to be type-checked and setting the stage to limit their visibility. the ones that have not yet been moved are mostly namespace-protected aliases for standard/public interfaces, which exist to facilitate implementing plain C functions in terms of POSIX functionality, or C or POSIX functionality in terms of extensions that are not standardized. some don't quite fit this description, but are "internally public" interfacs between subsystems of libc. rather than create a number of newly-named headers to declare these functions, and having to add explicit include directives for them to every source file where they're needed, I have introduced a method of wrapping the corresponding public headers. parallel to the public headers in $(srcdir)/include, we now have wrappers in $(srcdir)/src/include that come earlier in the include path order. they include the public header they're wrapping, then add declarations for namespace-protected versions of the same interfaces and any "internally public" interfaces for the subsystem they correspond to. along these lines, the wrapper for features.h is now responsible for the definition of the hidden, weak, and weak_alias macros. this means source files will no longer need to include any special headers to access these features. over time, it is my expectation that the scope of what is "internally public" will expand, reducing the number of source files which need to include *_impl.h and related headers down to those which are actually implementing the corresponding subsystems, not just using them.
2018-09-12move declarations of tls setup/access functions to pthread_impl.hRich Felker-2/+0
it's already included in all places where these are needed, and aside from __tls_get_addr, they're all implementation internals.
2018-09-12move __strftime_fmt_1 declaration to time_impl.hRich Felker-2/+2
this is a helper function from strftime that's also used by wcsftime.
2018-09-12move __tm_to_tzname declaration to time_impl.h with related functionsRich Felker-1/+1
this function was added later for strftime use and the existence of time_impl.h as the appropriate place for it seems to have been overlooked.
2018-09-12fix type-mismatched declarations of __nl_langinfo_l in source filesRich Felker-2/+2
obviously the type "should be" const, but it inherited non-const from the standard nl_langinfo_l.
2018-09-12use idiomatic weak alias approach for defining asctime_rRich Felker-33/+28
get rid of a gratuitous translation unit and call frame between asctime_r and the actual implementation of the function. this is the way gmtime_r and localtime_r are already done.
2018-09-12move and deduplicate declarations of __vdsosym to make it checkableRich Felker-2/+0
2018-08-27time: fix incorrect DST offset when using POSIX timezones without DSTA. Wilcox-1/+1
This manifests itself in mktime if tm_isdst = 1 and the current TZ= is a POSIX timezone specification. mktime would see that tm_isdst was set to 0 by __secs_to_zone, and subtract 'oppoff' (dst_off) - gmtoff from the resultant time. This meant that mktime returned a time that was exactly double the GMT offset of the desired timezone when tm_isdst was = 1.
2018-08-07fix sign of strftime %z output with offsets <1 hour west of UTCRich Felker-3/+2
the sign character produced came from the sign of tm_gmtoff/3600 as an integer division, which is zero for negative offsets smaller in magnitude than 3600. instead of printing the hours and minutes as separate fields, print them as a single value of the form hours*100+minutes, which naturally has the correct sign.
2018-06-26strftime: fix underlying format string in %z formatDaniel Sabogal-1/+1
the expression (tm->__tm_gmtoff)/3600 has type long. use %+.2ld instead.
2018-04-07implement wcsftime padding specifier extensionsSamuel Holland-3/+5
Commit 8a6bd7307da3fc4d08dd6a9277b611ccb4971354 added support for padding specifier extensions to strftime, but did not modify wcsftime. In the process, it added a parameter to __strftime_fmt_1 in strftime.c, but failed to update the prototype in wcsftime.c. This was found by compiling musl with LTO: src/time/wcsftime.c:7:13: warning: type of '__strftime_fmt_1' does \ not match original declaration [-Wlto-type-mismatch] Fix the prototype of __strftime_fmt_1 in wcsftime.c, and generate the 'pad' argument the same way as it is done in strftime.
2018-02-06adjust strftime + modifier to match apparent intent of POSIXRich Felker-6/+12
it's unclear from the specification whether the word "consumes" in "consumes more than four bytes to represent a year" refers just to significant places or includes leading zeros due to field width padding. however the examples in the rationale indicate that the latter was the intent. in particular, the year 270 is shown being formatted by %+5Y as +0270 rather than 00270. previously '+' prefixing was implemented just by comparing the year against 10000. instead, count the number of significant digits and padding bytes to be added, and use the total to determine whether to apply the '+' prefix. based on testing by Dennis Wölfing.
2018-02-05fix strftime field widths with %F format and zero yearRich Felker-1/+2
the code to strip initial sign and leading zeros inadvertently stripped all the zeros and the subsequent '-' separating the month. instead, only strip sign characters from the very first position, and only strip zeros when they are followed by another digit. based on testing by Dennis Wölfing.
2018-01-09revise the definition of multiple basic locks in the codeJens Gustedt-1/+1
In all cases this is just a change from two volatile int to one.
2017-12-14use the name UTC instead of GMT for UTC timezoneNatanael Copa-12/+12
notes by maintainer: both C and POSIX use the term UTC to specify related functionality, despite POSIX defining it as something more like UT1 or historical (pre-UTC) GMT without leap seconds. neither specifies the associated string for %Z. old choice of "GMT" violated principle of least surprise for users and some applications/tests. use "UTC" instead.
2017-12-11implement strftime padding specifier extensionsTimo Teräs-8/+14
notes added by maintainer: the '-' specifier allows default padding to be suppressed, and '_' allows padding with spaces instead of the default (zeros). these extensions seem to be included in several other implementations including FreeBSD and derivatives, and Solaris. while portable software should not depend on them, time format strings are often exposed to the user for configurable time display. reportedly some python programs also use and depend on them.
2017-11-09fix mismatched type of __pthread_tsd_run_dtors weak definitionRich Felker-2/+2
commit a6054e3c94aa0491d7366e4b05ae0d73f661bfe2 changed this function not to take an argument, but the weak definition used by timer_create was not updated to match. reported by Pascal Cuoq.
2017-06-20handle errors from localtime_r in ctime_rRich Felker-3/+2
POSIX requires ctime_r return a null pointer on failure, which can occur if the input time_t value is not representable in broken down form. based on patch by Alexander Monakov.
2017-06-15handle localtime errors in ctimeRich Felker-1/+3
ctime passes the result from localtime directly to asctime. But in case of error, localtime returns 0. This causes an error (NULL pointer dereference) in asctime. based on patch by Omer Anson.
2017-06-14getdate: correctly specify error numberA. Wilcox-1/+2
POSIX defines getdate error #5 as: "An I/O error is encountered while reading the template file." POSIX defines getdate error #7 as: "There is no line in the template that matches the input." This change correctly disambiguates between the two error conditions.
2017-03-21fix strptime output for %C without %yJulien Ramseier-2/+3
in this case, a potentially-uninitialized or unrelated existing value in tm_year was being used. instead use 0 if %y was not present.
2017-03-21fix processing of strptime %p formatJulien Ramseier-0/+2
string pointer was not advanced after matching.
2017-03-21fix off-by-one in strptime %jJulien Ramseier-0/+1
tm_yday range is 0-365 while %j is 1-366
2017-03-15fix POSIX-format TZ dst transition times for southern hemisphereRich Felker-8/+4
the time of day at which daylight time switches over is specified in local time in the dst state prior to the transition. the code for handling this wrongly assumed it needed to switch whether dst or standard offset is applied to the transition time when the dst end date is before the dst start date (souther hemisphere summer), but in fact the end transition time should always be adjusted for dst, and the start transition time should always be adjusted for standard time.
2017-01-02fix strftime %y for negative yearsRich Felker-2/+2
commit 583ea83541dcc6481c7a1bd1a9b485526bad84a1 fixed the case where tm_year is negative but the resulting year (offset by 1900) was still positive, which is always the case for time_t values that fit in 32 bits, but not for arbitrary inputs. based on an earlier patch by Julien Ramseier which was overlooked at the time the previous fix was applied.
2016-11-07fix integer overflow of tm_year in __secs_to_tmDaniel Sabogal-4/+5
the overflow check for years+100 did not account for the extra year computed from the remaining months. instead, perform this check after obtaining the final number of years.
2016-11-07fix parsing of quoted time zone namesHannu Nyman-1/+1
Fix parsing of the < > quoted time zone names. Compare the correct character instead of repeatedly comparing the first character.
2016-10-20fix gratuitous undefined behavior in strptimeRich Felker-2/+7
accessing an object of type const char *restrict as if it had type char * is not defined.
2016-10-20fix clock_nanosleep error caseDaniel Sabogal-1/+3
posix requires that EINVAL be returned if the first parameter specifies the cpu-time clock of the calling thread (CLOCK_THREAD_CPUTIME_ID). linux returns ENOTSUP instead so we handle this.
2016-10-06fix strftime %y for negative tm_yearSzabolcs Nagy-0/+1
2016-07-07fix asctime day/month names not to vary by localeRich Felker-5/+4
the FIXME comment here was overlooked at the time locale support was added.
2016-01-27improve clock_gettime and adapt it to support slightly-broken vdsoRich Felker-22/+39
these changes are motivated by a functionally similar patch by Hauke Mehrtens to address the needs of the new mips vdso clock_gettime, which wrongly fails with ENOSYS rather than falling back to making a syscall for clock ids it cannot handle from userspace. in the process of preparing to handle that case, it was noticed that the old clock_gettime use of the vdso was actually wrong with respect to error handling -- the tail call to the vdso function failed to set errno and instead returned an error code. since tail calls to vdso are no longer possible and since the plain syscall code is now needed as a fallback path anyway, it does not make sense to use a function pointer to call the plain syscall code path. instead, it's inlined at the end of the main clock_gettime function. the new code also avoids the need to test for initialization of the vdso function pointer by statically initializing it to a self-init function, and eliminates redundant loads from the volatile pointer object. finally, the use of a_cas_p on an object of type other than void *, which is not permitted aliasing, is replaced by using an object with the correct type and casting the value.
2015-10-14fix strftime handling of out-of-range struct tm fieldsRich Felker-8/+12
strftime results are unspecified in this case, but should not invoke undefined behaviour. tm_wday, tm_yday, tm_mon and tm_year fields were used in signed int arithmetic that could overflow. based on patch by Szabolcs Nagy.
2015-10-08fix integer overflows in time_t/struct tm conversion codeRich Felker-3/+3
as found and reported by Brian Mastenbrook, the expressions 400*qc_cycles and years+100 in __secs_to_tm were both subject to integer overflow for extreme values of the input t. this patch by Szabolcs Nagy fixes the code by switching to larger types, and matches the original intent I had in mind when writing this code.
2015-09-24avoid reading uninitialized memory in __map_fileSzabolcs Nagy-2/+3
The value of *size is not relevant in case of failure, but it's better not to copy garbage from the stack into it. (The compiler cannot see through the syscall, so optimization was not affected by the unspecified value).
2015-08-14match historical behavior for tm_gmtoff member of struct tmNatanael Copa-12/+12
tm_gmtoff is a nonstandard field, but on historical systems which have this field, it stores the offset of the local time zone from GMT or UTC. this is the opposite of the POSIX extern long timezone object and the offsets used in POSIX-form TZ strings, which represent the offset from local time to UTC. previously we were storing these negated offsets in tm_gmtoff too. programs which only used this field indirectly via strftime were not affected since strftime performed the negation for presentation. however, some programs and libraries accesse tm_gmtoff directly and were obtaining negated time zone offsets.
2015-07-06treat empty TZ environment variable as GMT rather than defaultRich Felker-1/+2
this improves compatibility with the behavior of other systems and with some applications which set an empty TZ var to disable use of local time by mktime, etc.
2015-03-03make all objects used with atomic operations volatileRich Felker-2/+2
the memory model we use internally for atomics permits plain loads of values which may be subject to concurrent modification without requiring that a special load function be used. since a compiler is free to make transformations that alter the number of loads or the way in which loads are performed, the compiler is theoretically free to break this usage. the most obvious concern is with atomic cas constructs: something of the form tmp=*p;a_cas(p,tmp,f(tmp)); could be transformed to a_cas(p,*p,f(*p)); where the latter is intended to show multiple loads of *p whose resulting values might fail to be equal; this would break the atomicity of the whole operation. but even more fundamental breakage is possible. with the changes being made now, objects that may be modified by atomics are modeled as volatile, and the atomic operations performed on them by other threads are modeled as asynchronous stores by hardware which happens to be acting on the request of another thread. such modeling of course does not itself address memory synchronization between cores/cpus, but that aspect was already handled. this all seems less than ideal, but it's the best we can do without mandating a C11 compiler and using the C11 model for atomics. in the case of pthread_once_t, the ABI type of the underlying object is not volatile-qualified. so we are assuming that accessing the object through a volatile-qualified lvalue via casts yields volatile access semantics. the language of the C standard is somewhat unclear on this matter, but this is an assumption the linux kernel also makes, and seems to be the correct interpretation of the standard.
2014-10-09fix handling of negative offsets in timezone spec stringsRich Felker-10/+7
previously, the hours were considered as a signed quantity while minutes and seconds were always treated as positive offsets. however, semantically the '-' sign should negate the whole hh:mm:ss offset. this bug only affected timezones east of GMT with non-whole-hours offsets, such as those used in India and Nepal.
2014-09-06add C11 timespec_get function, with associated time.h changes for C11Rich Felker-0/+12
based on patch by Jens Gustedt for inclusion with C11 threads implementation, but committed separately since it's independent of threads.