1. 06 11月, 2014 1 次提交
    • S
      math: fix x86_64 and x32 asm not to use sahf instruction · a732e80d
      Szabolcs Nagy 提交于
      Some early x86_64 cpus (released before 2006) did not support sahf/lahf
      instructions so they should be avoided (intel manual says they are only
      supported if CPUID.80000001H:ECX.LAHF-SAHF[bit 0] = 1).
      
      The workaround simplifies exp2l and expm1l because fucomip can be
      used instead of the fucomp;fnstsw;sahf sequence copied from i386.
      
      In fmodl and remainderl sahf is replaced by a simple bit test.
      a732e80d
  2. 05 11月, 2014 1 次提交
    • R
      fix 64-bit syscall argument passing on or1k · de2b9c21
      Rich Felker 提交于
      the kernel syscall interface for or1k does not expect 64-bit arguments
      to be aligned to "even" register boundaries. this incorrect alignment
      broke truncate/ftruncate and as well as a few less-common syscalls.
      de2b9c21
  3. 01 11月, 2014 1 次提交
  4. 31 10月, 2014 4 次提交
    • S
      math: use the rounding idiom consistently · 0ce946cf
      Szabolcs Nagy 提交于
      the idiomatic rounding of x is
      
        n = x + toint - toint;
      
      where toint is either 1/EPSILON (x is non-negative) or 1.5/EPSILON
      (x may be negative and nearest rounding mode is assumed) and EPSILON is
      according to the evaluation precision (the type of toint is not very
      important, because single precision float can represent the 1/EPSILON of
      ieee binary128).
      
      in case of FLT_EVAL_METHOD!=0 this avoids a useless store to double or
      float precision, and the long double code became cleaner with
      1/LDBL_EPSILON instead of ifdefs for toint.
      
      __rem_pio2f and __rem_pio2 functions slightly changed semantics:
      on i386 a double-rounding is avoided so close to half-way cases may
      get evaluated differently eg. as sin(pi/4-eps) instead of cos(pi/4+eps)
      0ce946cf
    • S
      fix rint.c and rintf.c when FLT_EVAL_METHOD!=0 · 79ca8609
      Szabolcs Nagy 提交于
      The old code used the rounding idiom incorrectly:
      
        y = (double)(x + 0x1p52) - 0x1p52;
      
      the cast is useless if FLT_EVAL_METHOD==0 and causes a second rounding
      if FLT_EVAL_METHOD==2 which can give incorrect result in nearest rounding
      mode, so the correct idiom is to add/sub a power-of-2 according to the
      characteristics of double_t.
      
      This did not cause actual bug because only i386 is affected where rint
      is implemented in asm.
      
      Other rounding functions use a similar idiom, but they give correct
      results because they only rely on getting a neighboring integer result
      and the rounding direction is fixed up separately independently of the
      current rounding mode. However they should be fixed to use the idiom
      correctly too.
      79ca8609
    • R
      fix invalid access by openat to possibly-missing variadic mode argument · 2da3ab13
      Rich Felker 提交于
      the mode argument is only required to be present when the O_CREAT or
      O_TMPFILE flag is used.
      2da3ab13
    • R
      9d836ea7
  5. 20 10月, 2014 1 次提交
    • R
      manually "shrink wrap" fast path in pthread_once · dc95322e
      Rich Felker 提交于
      this change is a workaround for the inability of current compilers to
      perform "shrink wrapping" optimizations. in casual testing, it roughly
      doubled the performance of pthread_once when called on an
      already-finished once control object.
      dc95322e
  6. 15 10月, 2014 2 次提交
  7. 14 10月, 2014 2 次提交
  8. 11 10月, 2014 2 次提交
    • R
      fix missing barrier in pthread_once/call_once shortcut path · df37d396
      Rich Felker 提交于
      these functions need to be fast when the init routine has already run,
      since they may be called very often from code which depends on global
      initialization having taken place. as such, a fast path bypassing
      atomic cas on the once control object was used to avoid heavy memory
      contention. however, on archs with weakly ordered memory, the fast
      path failed to ensure that the caller actually observes the side
      effects of the init routine.
      
      preliminary performance testing showed that simply removing the fast
      path was not practical; a performance drop of roughly 85x was observed
      with 20 threads hammering the same once control on a 24-core machine.
      so the new explicit barrier operation from atomic.h is used to retain
      the fast path while ensuring memory visibility.
      
      performance may be reduced on some archs where the barrier actually
      makes a difference, but the previous behavior was unsafe and incorrect
      on these archs. future improvements to the implementation of a_barrier
      should reduce the impact.
      df37d396
    • R
      add explicit barrier operation to internal atomic.h API · 867b1822
      Rich Felker 提交于
      867b1822
  9. 10 10月, 2014 1 次提交
    • R
      fix handling of negative offsets in timezone spec strings · 08b996d1
      Rich Felker 提交于
      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.
      08b996d1
  10. 08 10月, 2014 4 次提交
    • S
      add new linux file sealing api to fcntl.h · a3763d64
      Szabolcs Nagy 提交于
      new in linux v3.17 commit 40e041a2c858b3caefc757e26cb85bfceae5062b
      sealing allows some operations to be blocked on a file which makes
      file access safer when fds are shared between processes (only
      supported for shared mem fds currently)
      
      flags:
      F_SEAL_SEAL prevents further sealing
      F_SEAL_SHRINK prevents file from shrinking
      F_SEAL_GROW prevents file from growing
      F_SEAL_WRITE prevents writes
      
      fcntl commands:
      F_GET_SEALS get the current seal flags
      F_ADD_SEALS add new seal flags
      a3763d64
    • S
      add new IPV6_AUTOFLOWLABEL socket option in netinet/in.h · a0c90b97
      Szabolcs Nagy 提交于
      added in linux v3.17 commit 753a2ad54ef45e3417a9d49537c2b42b04a2e1be
      enables automatic flow label generation on transmit
      a0c90b97
    • S
      add new syscall numbers for seccomp, getrandom, memfd_create · 4ffc39c6
      Szabolcs Nagy 提交于
      these syscalls are new in linux v3.17 and present on all supported
      archs except sh.
      
      seccomp was added in commit 48dc92b9fc3926844257316e75ba11eb5c742b2c
      it has operation, flags and pointer arguments (if flags==0 then it is
      the same as prctl(PR_SET_SECCOMP,...)), the uapi header for flag
      definitions is linux/seccomp.h
      
      getrandom was added in commit c6e9d6f38894798696f23c8084ca7edbf16ee895
      it provides an entropy source when open("/dev/urandom",..) would fail,
      the uapi header for flags is linux/random.h
      
      memfd_create was added in commit 9183df25fe7b194563db3fec6dc3202a5855839c
      it allows anon mmap to have an fd, that can be shared, sealed and needs no
      mount point, the uapi header for flags is linux/memfd.h
      4ffc39c6
    • R
      always provide __fpclassifyl and __signbitl definitions · 0539e6da
      Rich Felker 提交于
      previously the external definitions of these functions were omitted on
      archs where long double is the same as double, since the code paths in
      the math.h macros which would call them are unreachable. however, even
      if they are unreachable, the definitions are still mandatory. omitting
      them is invalid C, and in the case of a non-optimizing compiler, will
      result in a link error.
      0539e6da
  11. 07 10月, 2014 1 次提交
    • R
      ignore access mode bits of flags in mkostemps and functions that use it · 6f1c1fe9
      Rich Felker 提交于
      per the text accepted for inclusion in POSIX, behavior is unspecified
      when any of the access mode bits are set. since it's impossible to
      consistently report this usage error (O_RDONLY could not be detected
      since its value happens to be zero), the most consistent way to handle
      them is just to ignore them.
      
      previously, if a caller erroneously passed O_WRONLY, the resulting
      access mode would be O_WRONLY|O_RDWR, which has the value 3, and this
      resulted in a file descriptor which rejects both read and write
      attempts when it is subsequently used.
      6f1c1fe9
  12. 04 10月, 2014 1 次提交
    • R
      fix handling of odd lengths in swab function · dccbf4c8
      Rich Felker 提交于
      this function is specified to leave the last byte with "unspecified
      disposition" when the length is odd, so for the most part correct
      programs should not be calling swab with odd lengths. however, doing
      so is permitted, and should not write past the end of the destination
      buffer.
      dccbf4c8
  13. 23 9月, 2014 1 次提交
    • R
      fix incorrect sequence generation in *rand48 prng functions · 05cef96d
      Rich Felker 提交于
      patch by Jens Gustedt. this fixes a bug reported by Nadav Har'El. the
      underlying issue was that a left-shift by 16 bits after promotion of
      unsigned short to int caused integer overflow. while some compilers
      define this overflow case as "shifting into the sign bit", doing so
      doesn't help; the sign bit then gets extended through the upper bits
      in subsequent arithmetic as unsigned long long. this patch imposes a
      promotion to unsigned prior to the shift, so that the result is
      well-defined and matches the specified behavior.
      05cef96d
  14. 20 9月, 2014 1 次提交
    • R
      fix linked list corruption in flockfile lists · 3e936ce8
      Rich Felker 提交于
      commit 5345c9b8 added a linked list to
      track the FILE streams currently locked (via flockfile) by a thread.
      due to a failure to fully link newly added members, removal from the
      list could leave behind references which could later result in writes
      to already-freed memory and possibly other memory corruption.
      
      implicit stdio locking was unaffected; the list is only used in
      conjunction with explicit flockfile locking.
      
      this bug was not present in any releases; it was introduced and fixed
      during the same release cycle.
      
      patch by Timo Teräs, who discovered and tracked down the bug.
      3e936ce8
  15. 18 9月, 2014 1 次提交
  16. 17 9月, 2014 1 次提交
    • R
      fix overflow corner case in strtoul-family functions · e2e1bb81
      Rich Felker 提交于
      incorrect behavior occurred only in cases where the input overflows
      unsigned long long, not just the (possibly lower) range limit for the
      result type. in this case, processing of the '-' sign character was
      not suppressed, and the function returned a value of 1 despite setting
      errno to ERANGE.
      e2e1bb81
  17. 13 9月, 2014 1 次提交
    • S
      rewrite the regex pattern parser in regcomp · ec1aed0a
      Szabolcs Nagy 提交于
      The new code is a bit simpler and the generated code is about 1KB
      smaller (on i386). The basic design was kept including internal
      interfaces, TNFA generation was not touched.
      
      The old tre parser had various issues:
      
      [^aa-z]
      negated overlapping ranges in a bracket expression were handled
      incorrectly (eg [^aa-z] was handled as [^a] instead of [^a-z])
      
      a{,2}
      missing lower bound in a counted repetition should be an error,
      but it was accepted with broken semantics: a{,2} was treated as
      a{0,3}, the new parser rejects it
      
      a{999,}
      large min count was not rejected (a{5000,} failed with REG_ESPACE
      due to reaching a stack limit), the new parser enforces the
      RE_DUP_MAX limit
      
      \xff
      regcomp used to accept a pattern with illegal sequences in it
      (treated them as empty expression so p\xffq matched pq) the new
      parser rejects such patterns with REG_BADPAT or REG_ERANGE
      
      [^b-fD-H] with REG_ICASE
      old parser turned this into [^b-fB-F] because of the negated
      overlapping range issue (see above), the new parser treats it
      as [^b-hB-H], POSIX seems to require [^d-fD-F], but practical
      implementations do case-folding first and negate the character
      set later instead of the other way around. (Supporting the posix
      way efficiently would require significant changes so it was left
      as is, it is unclear if any application actually expects the
      posix behaviour, this issue is raised on the austingroup tracker:
      http://austingroupbugs.net/view.php?id=872 ).
      
      another case-insensitive matching issue is that unicode case
      folding rules can group more than two characters together while
      towupper and towlower can only work for a pair of upper and
      lower case characters, this is a limitation of POSIX so it is
      not fixed.
      
      invalid bracket and brace expressions may return different error
      codes now (REG_ERANGE instead of REG_EBRACK or REG_BADBR instead
      of REG_EBRACE) otherwise the new parser should be compatible with
      the old one.
      
      regcomp should be able to handle arbitrary pattern input if the
      pattern length is limited, the only exception is the use of large
      repetition counts (eg. (a{255}){255}) which require exp amount
      of memory and there is no easy workaround.
      ec1aed0a
  18. 11 9月, 2014 4 次提交
    • R
      fix C++ incompatibility in i386 definition of max_align_t · bd082916
      Rich Felker 提交于
      the C11 _Alignas keyword is not present in C++, and despite it being
      in the reserved namespace and thus reasonable to support even in
      non-C11 modes, compilers seem to fail to support it.
      bd082916
    • R
      add _DEFAULT_SOURCE feature profile as an alias for _BSD_SOURCE · 5edbc6fe
      Rich Felker 提交于
      as a result of commit ab8f6a6e, this
      definition is now equivalent to the actual "default profile" which
      appears immediately below in features.h, and which defines both
      _BSD_SOURCE and _XOPEN_SOURCE.
      
      the intent of providing a _DEFAULT_SOURCE, which glibc also now
      provides, is to give applications a way to "get back" the default
      feature profile when it was lost either by compiler flags that inhibit
      it (such as -std=c99) or by library-provided predefined macros (such
      as -D_POSIX_C_SOURCE=200809L) which may inhibit exposure of features
      that were otherwise visible by default and which the application may
      need. without _DEFAULT_SOURCE, the application had encode knowledge of
      a particular libc's defaults, and such knowledge was fragile and
      subject to bitrot.
      
      eventually the names _GNU_SOURCE and _BSD_SOURCE should be phased out
      in favor of the more-descriptive and more-accurate _ALL_SOURCE and
      _DEFAULT_SOURCE, leaving the old names as aliases but using the new
      ones internally. however this is a more invasive change that would
      require extensive regression testing, so it is deferred.
      5edbc6fe
    • R
      fix _ALL_SOURCE logic to avoid possible redefinition of _GNU_SOURCE · f929493c
      Rich Felker 提交于
      this could be an error if _GNU_SOURCE was already defined differently
      by the application.
      f929493c
    • R
      fix places where _BSD_SOURCE failed to yield a superset of _XOPEN_SOURCE · ab8f6a6e
      Rich Felker 提交于
      the vast majority of these failures seem to have been oversights at
      the time _BSD_SOURCE was added, or perhaps shortly afterward. the one
      which may have had some reason behind it is omission of setpgrp from
      the _BSD_SOURCE feature profile, since the standard setpgrp interface
      conflicts with a legacy (pre-POSIX) BSD interface by the same name.
      however, such omission is not aligned with our general policy in this
      area (for example, handling of similar _GNU_SOURCE cases) and should
      not be preserved.
      ab8f6a6e
  19. 08 9月, 2014 3 次提交
    • S
      fix exp10l.c to include float.h · e6403887
      Szabolcs Nagy 提交于
      the previous commit was a no op in exp10l because LDBL_* macros
      were implicitly 0 (the preprocessor does not warn about undefined
      symbols).
      e6403887
    • S
      prune math code on archs with binary64 long double · 0c32c263
      Szabolcs Nagy 提交于
      __polevll, __p1evll and exp10l were provided on archs when long double
      is the same as double. The first two were completely unused and exp10l
      can be a wrapper around exp10.
      0c32c263
    • S
      add new F_OFD_* macros to fcntl.h (open file description locks) · 976bb28f
      Szabolcs Nagy 提交于
      open file description locks are inherited across fork and only auto
      dropped after the last fd of the file description is closed, they can be
      used to synchronize between threads that open separate file descriptions
      for the same file.
      
      new in linux 3.15 commit 0d3f7a2dd2f5cf9642982515e020c1aee2cf7af6
      976bb28f
  20. 07 9月, 2014 7 次提交
    • R
      add C11 thread creation and related thread functions · 23614b0f
      Rich Felker 提交于
      based on patch by Jens Gustedt.
      
      the main difficulty here is handling the difference between start
      function signatures and thread return types for C11 threads versus
      POSIX threads. pointers to void are assumed to be able to represent
      faithfully all values of int. the function pointer for the thread
      start function is cast to an incorrect type for passing through
      pthread_create, but is cast back to its correct type before calling so
      that the behavior of the call is well-defined.
      
      changes to the existing threads implementation were kept minimal to
      reduce the risk of regressions, and duplication of code that carries
      implementation-specific assumptions was avoided for ease and safety of
      future maintenance.
      23614b0f
    • J
      add C11 condition variable functions · 14397cec
      Jens Gustedt 提交于
      Because of the clear separation for private pthread_cond_t these
      interfaces are quite simple and direct.
      14397cec
    • J
      add C11 mutex functions · 8b047293
      Jens Gustedt 提交于
      8b047293
    • J
      add C11 thread functions operating on tss_t and once_flag · e16f70f4
      Jens Gustedt 提交于
      These all have POSIX equivalents, but aside from tss_get, they all
      have minor changes to the signature or return value and thus need to
      exist as separate functions.
      e16f70f4
    • R
      add threads.h and needed per-arch types for mtx_t and cnd_t · b7cf71a1
      Rich Felker 提交于
      based on patch by Jens Gustedt.
      
      mtx_t and cnd_t are defined in such a way that they are formally
      "compatible types" with pthread_mutex_t and pthread_cond_t,
      respectively, when accessed from a different translation unit. this
      makes it possible to implement the C11 functions using the pthread
      functions (which will dereference them with the pthread types) without
      having to use the same types, which would necessitate either namespace
      violations (exposing pthread type names in threads.h) or incompatible
      changes to the C++ name mangling ABI for the pthread types.
      
      for the rest of the types, things are much simpler; using identical
      types is possible without any namespace considerations.
      b7cf71a1
    • J
      use weak symbols for the POSIX functions that will be used by C threads · df7d0dfb
      Jens Gustedt 提交于
      The intent of this is to avoid name space pollution of the C threads
      implementation.
      
      This has two sides to it. First we have to provide symbols that wouldn't
      pollute the name space for the C threads implementation. Second we have
      to clean up some internal uses of POSIX functions such that they don't
      implicitly drag in such symbols.
      df7d0dfb
    • R
      add C11 timespec_get function, with associated time.h changes for C11 · 6eb19505
      Rich Felker 提交于
      based on patch by Jens Gustedt for inclusion with C11 threads
      implementation, but committed separately since it's independent of
      threads.
      6eb19505