Commit graph

16 commits

Author SHA1 Message Date
Elliott Hughes
37ad959783 More missing _unlocked <stdio.h> functions.
Also simplify trivial one-liners like perror/puts/fputs, and clean up
fread/fwrite slightly.

Fix perror to match POSIX.

Add basic perror and *_unlocked tests.

Bug: N/A
Test: ran tests
Change-Id: I63f83c8e0c15c3c4096509d17421ac331b6fc23d
2017-10-31 13:23:41 -07:00
Elliott Hughes
c8a2612ffc Merge "Implement pthread_attr_getinheritsched/pthread_attr_setinheritsched." 2017-10-26 16:12:04 +00:00
Elliott Hughes
8aecba7aa6 Implement pthread_attr_getinheritsched/pthread_attr_setinheritsched.
Historically, Android defaulted to EXPLICIT but with a special case
because SCHED_NORMAL/priority 0 was awkward. Because the code couldn't
actually tell whether SCHED_NORMAL/priority 0 was a genuine attempt to
explicitly set those attributes (because the parent thread is SCHED_FIFO,
say) or just because the pthread_attr_t was left at its defaults.

Now we support INHERIT, we could call sched_getscheduler to see whether
we actually need to call sched_setscheduler, but since the major cost
is the fixed syscall overhead, we may as well just conservatively
call sched_setscheduler and let the kernel decide whether it's a
no-op. (Especially because we'd then have to add both sched_getscheduler
and sched_setscheduler to any seccomp filter.)

Platform code (or app code that only needs to support >= P) can actually
add a call to pthread_attr_setinheritsched to say that they just want
to inherit (if they know that none of their threads actually mess with
scheduler attributes at all), which will save them a sched_setscheduler
call except in the doubly-special case of SCHED_RESET_ON_FORK (which we
do handle).

An alternative would be "make pthread_attr_setschedparams and
pthread_attr_setschedprio set EXPLICIT and change the platform default
to INHERIT", but even though I can only think of weird pathological
examples where anyone would notice that change, that behavior -- of
pthread_attr_setschedparams/pthread_attr_setschedprio overriding an
earlier call to pthread_attr_setinheritsched -- isn't allowed by POSIX
(whereas defaulting to EXPLICIT is).

If we have a lot of trouble with this change in the app compatibility
testing phase, though, we'll want to reconsider this decision!

 -*-

This change also removes a comment about setting the scheduler attributes
in main_thread because we'd have to actually keep them up to date,
and it's not clear that doing so would be worth the trouble.

Also make async_safe_format_log preserve errno so we don't have to be
so careful around it.

Bug: http://b/67471710
Test: ran tests
Change-Id: Idd026c4ce78a536656adcb57aa2e7b2c616eeddf
2017-10-25 14:28:42 -07:00
Treehugger Robot
8c73809bf5 Merge "Ignore sockatmark." 2017-10-20 12:34:58 +00:00
Treehugger Robot
38bd71bab7 Merge "Update docs/status.md now fexecve is implemented." 2017-10-19 23:07:36 +00:00
Elliott Hughes
61c9c80275 Ignore sockatmark.
I was unable to find a single use of this anywhere, and the networking
folks point out https://tools.ietf.org/html/rfc6093:

    """
    5.  Advice to New Applications Employing TCP

      As a result of the issues discussed in Section 3.2 and Section 3.4,
      new applications SHOULD NOT employ the TCP urgent mechanism.
    """

Applications that think they want to do these tricksy things should be
referred to section 3.4, wherein it's noted that these semantics are
effectively dead and it's middleboxes what killed 'em:

    """
    3.4.  Interaction of Middleboxes with TCP Urgent Indications

      As a result of the publication of Network Intrusion Detection System
      (NIDS) evasion techniques based on TCP urgent indications [phrack],
      some middleboxes clear the urgent indications by clearing the URG
      flag and setting the Urgent Pointer to zero.  This causes the "urgent
      data" to become "in line" (that is, accessible by the read(2) call or
      the recv(2) call without the MSG_OOB flag) in the case of those TCP
      implementations that interpret the TCP urgent mechanism as a facility
      for delivering "out-of-band" data (as described in Section 3.1).  An
      example of such a middlebox is the Cisco PIX firewall [Cisco-PIX].
      This should discourage applications from depending on urgent
      indications for their correct operation, as urgent indications may
      not be reliable in the current Internet.
    """

Bug: N/A
Test: N/A
Change-Id: I73280db1d803bb7bd93954c13c653fa0cd3daff9
2017-10-19 15:37:54 -07:00
Treehugger Robot
ac29d9f3b9 Merge "Add POSIX swab." 2017-10-19 21:49:29 +00:00
Elliott Hughes
bdb1e89104 Update docs/status.md now fexecve is implemented.
Bug: N/A
Test: N/A
Change-Id: Id0b9179a073f56e6264774db198b9e89d5e2ff95
2017-10-19 14:35:18 -07:00
Elliott Hughes
01a57d1eb6 Call fmtmsg/getdate/getdate_err useless.
They're POSIX, and they're implemented in iOS and glibc, but they're
not actually used in any codebase I have access to. They're *defined*
in several places, and some of those places have a handful of tests,
but I couldn't find a single genuine caller.

Bug: N/A
Test: N/A
Change-Id: Id3e2c36183fcff323aa5a2e3a3dabaa8378fae56
2017-10-19 15:45:04 +00:00
Elliott Hughes
fa386e0d1e Add POSIX swab.
Surprisingly to me, there are actual uses of `swab` in the codebases
I have available to search, including one with a #ifndef __ANDROID__
around it.

Bug: N/A
Test: ran tests
Change-Id: Ic91b78ae22bb65c346cb46dd38916f48d979abe0
2017-10-18 13:34:32 -07:00
Elliott Hughes
dff08ced56 Add pthread_setschedprio.
Bug: http://b/26204555
Test: ran tests
Change-Id: Ic34062b9b6036a1ce2642a069514bab48a893338
2017-10-17 09:14:05 -07:00
Elliott Hughes
5033918092 Complete <netdb.h>.
Add all the missing <netdb.h> functions.

Also fix getservbyport to handle a null protocol correctly.

Also fix getservbyname/getservbyport to not interfere with getservent.

Also fix endservent to reset getservent iteration.

Also reduce unnecessary differences from upstream NetBSD sethostent.c.

The servent implementation is still horrific, and we should
probably support protoent too so that debugging tools can use
getprotobyname/getprotobynumber.

Bug: N/A
Test: ran tests
Change-Id: I639108c46df0a768af297cf3bbce857cb1bef9d9
2017-10-15 10:37:51 -07:00
Elliott Hughes
62446279f3 Ignore pthread_getconcurrency/pthread_setconcurrency.
They're marked obsolescent in POSIX, don't clearly mean anything, aren't
portable because the values don't mean anything, and are no-ops in other
C libraries that do "implement" them.

Bug: N/A
Test: N/A
Change-Id: I07342a0a6a5f6616a8432bfea24ed944c7971d27
2017-10-13 10:21:37 -07:00
Elliott Hughes
d036a8dd17 Ignore endutxent.
We have no utmp, and we're ignoring getutxent/setutxent, and endutxent
belongs in the same group.

Bug: N/A
Test: N/A
Change-Id: Ide032960a0f95750f3bb8f2e62a25e5e7d25c7b6
2017-10-12 20:32:22 -07:00
Elliott Hughes
14e3ff9f09 Implement <spawn.h>.
As described here:

  http://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_spawn.html

And here:

  http://man7.org/linux/man-pages/man3/posix_spawn.3.html

Bug: N/A (but mentioned in my inbox since 2013)
Test: ran tests
Change-Id: I0b27b2919b660779e3bd8a25fb429527c16dc621
2017-10-11 14:57:49 -07:00
Elliott Hughes
0bfcbaf4d0 Add new status document, based on internal wiki.
Also start breaking up the monolithic top level README.md, pulling the
32-bit ABI stuff out into its own file, and moving the remaining benchmark
documentation in with the rest of the benchmark documentation.

Bug: N/A
Test: N/A
Change-Id: Ic1b9995e27b5044199ed34883cc0b8faa894df0e
2017-08-29 11:07:36 -07:00