Commit graph

45 commits

Author SHA1 Message Date
Justine Tunney
ee8a861635
Fix semaphore deadlock on Apple Silicon 2023-10-03 09:26:46 -07:00
Justine Tunney
ff77f2a6af
Make improvements
- This change fixes a bug that allowed unbuffered printf() output (to
  streams like stderr) to be truncated. This regression was introduced
  some time between now and the last release.

- POSIX specifies all functions as thread safe by default. This change
  works towards cleaning up our use of the @threadsafe / @threadunsafe
  documentation annotations to reflect that. The goal is (1) to use
  @threadunsafe to document functions which POSIX say needn't be thread
  safe, and (2) use @threadsafe to document functions that we chose to
  implement as thread safe even though POSIX didn't mandate it.

- Tidy up the clock_gettime() implementation. We're now trying out a
  cleaner approach to system call support that aims to maintain the
  Linux errno convention as long as possible. This also fixes bugs that
  existed previously, where the vDSO errno wasn't being translated
  properly. The gettimeofday() system call is now a wrapper for
  clock_gettime(), which reduces bloat in apps that use both.

- The recently-introduced improvements to the execute bit on Windows has
  had bugs fixed. access(X_OK) on a directory on Windows now succeeds.
  fstat() will now perform the MZ/#! ReadFile() operation correctly.

- Windows.h is no longer included in libc/isystem/, because it confused
  PCRE's build system into thinking Cosmopolitan is a WIN32 platform.
  Cosmo's Windows.h polyfill was never even really that good, since it
  only defines a subset of the subset of WIN32 APIs that Cosmo defines.

- The setlongerjmp() / longerjmp() APIs are removed. While they're nice
  APIs that are superior to the standardized setjmp / longjmp functions,
  they weren't superior enough to not be dead code in the monorepo. If
  you use these APIs, please file an issue and they'll be restored.

- The .com appending magic has now been removed from APE Loader.
2023-10-03 06:17:16 -07:00
Justine Tunney
ec480f5aa0
Make improvements
- Every unit test now passes on Apple Silicon. The final piece of this
  puzzle was porting our POSIX threads cancelation support, since that
  works differently on ARM64 XNU vs. AMD64. Our semaphore support on
  Apple Silicon is also superior now compared to AMD64, thanks to the
  grand central dispatch library which lets *NSYNC locks go faster.

- The Cosmopolitan runtime is now more stable, particularly on Windows.
  To do this, thread local storage is mandatory at all runtime levels,
  and the innermost packages of the C library is no longer being built
  using ASAN. TLS is being bootstrapped with a 128-byte TIB during the
  process startup phase, and then later on the runtime re-allocates it
  either statically or dynamically to support code using _Thread_local.
  fork() and execve() now do a better job cooperating with threads. We
  can now check how much stack memory is left in the process or thread
  when functions like kprintf() / execve() etc. call alloca(), so that
  ENOMEM can be raised, reduce a buffer size, or just print a warning.

- POSIX signal emulation is now implemented the same way kernels do it
  with pthread_kill() and raise(). Any thread can interrupt any other
  thread, regardless of what it's doing. If it's blocked on read/write
  then the killer thread will cancel its i/o operation so that EINTR can
  be returned in the mark thread immediately. If it's doing a tight CPU
  bound operation, then that's also interrupted by the signal delivery.
  Signal delivery works now by suspending a thread and pushing context
  data structures onto its stack, and redirecting its execution to a
  trampoline function, which calls SetThreadContext(GetCurrentThread())
  when it's done.

- We're now doing a better job managing locks and handles. On NetBSD we
  now close semaphore file descriptors in forked children. Semaphores on
  Windows can now be canceled immediately, which means mutexes/condition
  variables will now go faster. Apple Silicon semaphores can be canceled
  too. We're now using Apple's pthread_yield() funciton. Apple _nocancel
  syscalls are now used on XNU when appropriate to ensure pthread_cancel
  requests aren't lost. The MbedTLS library has been updated to support
  POSIX thread cancelations. See tool/build/runitd.c for an example of
  how it can be used for production multi-threaded tls servers. Handles
  on Windows now leak less often across processes. All i/o operations on
  Windows are now overlapped, which means file pointers can no longer be
  inherited across dup() and fork() for the time being.

- We now spawn a thread on Windows to deliver SIGCHLD and wakeup wait4()
  which means, for example, that posix_spawn() now goes 3x faster. POSIX
  spawn is also now more correct. Like Musl, it's now able to report the
  failure code of execve() via a pipe although our approach favors using
  shared memory to do that on systems that have a true vfork() function.

- We now spawn a thread to deliver SIGALRM to threads when setitimer()
  is used. This enables the most precise wakeups the OS makes possible.

- The Cosmopolitan runtime now uses less memory. On NetBSD for example,
  it turned out the kernel would actually commit the PT_GNU_STACK size
  which caused RSS to be 6mb for every process. Now it's down to ~4kb.
  On Apple Silicon, we reduce the mandatory upstream thread size to the
  smallest possible size to reduce the memory overhead of Cosmo threads.
  The examples directory has a program called greenbean which can spawn
  a web server on Linux with 10,000 worker threads and have the memory
  usage of the process be ~77mb. The 1024 byte overhead of POSIX-style
  thread-local storage is now optional; it won't be allocated until the
  pthread_setspecific/getspecific functions are called. On Windows, the
  threads that get spawned which are internal to the libc implementation
  use reserve rather than commit memory, which shaves a few hundred kb.

- sigaltstack() is now supported on Windows, however it's currently not
  able to be used to handle stack overflows, since crash signals are
  still generated by WIN32. However the crash handler will still switch
  to the alt stack, which is helpful in environments with tiny threads.

- Test binaries are now smaller. Many of the mandatory dependencies of
  the test runner have been removed. This ensures many programs can do a
  better job only linking the the thing they're testing. This caused the
  test binaries for LIBC_FMT for example, to decrease from 200kb to 50kb

- long double is no longer used in the implementation details of libc,
  except in the APIs that define it. The old code that used long double
  for time (instead of struct timespec) has now been thoroughly removed.

- ShowCrashReports() is now much tinier in MODE=tiny. Instead of doing
  backtraces itself, it'll just print a command you can run on the shell
  using our new `cosmoaddr2line` program to view the backtrace.

- Crash report signal handling now works in a much better way. Instead
  of terminating the process, it now relies on SA_RESETHAND so that the
  default SIG_IGN behavior can terminate the process if necessary.

- Our pledge() functionality has now been fully ported to AARCH64 Linux.
2023-09-18 21:04:47 -07:00
Justine Tunney
a359de7893
Get rid of kmalloc()
This changes *NSYNC to allocate waiters on the stack so our locks don't
need to depend on dynamic memory. This make our runtiem simpler, and it
also fixes bugs with thread cancellation support.
2023-09-11 21:56:00 -07:00
Justine Tunney
f531acc8f9
Make improvements
- Invent openatemp() API
- Invent O_UNLINK open flag
- Introduce getenv_secure() API
- Remove `git pull` from cosmocc
- Fix utimes() when path is NULL
- Fix mktemp() to never return NULL
- Fix utimensat() UTIME_OMIT on XNU
- Improve utimensat() code for RHEL5
- Turn `argv[0]` C:/ to /C/ on Windows
- Introduce tmpnam() and tmpnam_r() APIs
- Fix more const issues with internal APIs
- Permit utimes() on WIN32 in O_RDONLY mode
- Fix fdopendir() to check fd is a directory
- Fix recent crash regression in landlock make
- Fix futimens(AT_FDCWD, NULL) to return EBADF
- Use workaround so `make -j` doesn't fork bomb
- Rename dontdiscard to __wur (just like glibc)
- Fix st_size for WIN32 symlinks containing UTF-8
- Introduce stdio ext APIs needed by GNU coreutils
- Fix lstat() on WIN32 for symlinks to directories
- Move some constants from normalize.inc to limits.h
- Fix segv with memchr() and memcmp() overlapping page
- Implement POSIX fflush() behavior for reader streams
- Implement AT_SYMLINK_NOFOLLOW for utimensat() on WIN32
- Don't change read-only status of existing files on WIN32
- Correctly handle `0x[^[:xdigit:]]` case in strtol() functions
2023-09-06 12:34:59 -07:00
Justine Tunney
0d748ad58e
Fix warnings
This change fixes Cosmopolitan so it has fewer opinions about compiler
warnings. The whole repository had to be cleaned up to be buildable in
-Werror -Wall mode. This lets us benefit from things like strict const
checking. Some actual bugs might have been caught too.
2023-09-01 20:50:18 -07:00
Justine Tunney
965516e313
Make improvements for Actually Portable Emacs
- Get SIGWINCH working again on the New Technology
- Correctly handle O_NOFOLLOW in open() on Windows
- Implement synthetic umask() functionality on Windows
- Do a better job managing file execute access on Windows
- Fill in `st_uid` and `st_gid` with username hash on Windows
- Munge UNICODE control pictures into control codes on Windows
- Do a better job ensuring Windows console settings are restored
- Introduce KPRINTF_LOG environment variable to log kprintf to a file
2023-08-19 06:44:58 -07:00
Justine Tunney
58352df0a4
Make forking off threads reliable on Windows
This change makes posix_spawn_test no longer flaky on Windows, by (1)
fixing a race condition in wait(), and (2) removing a misguided vfork
implementation which was letting Windows bypass pthread_atfork().
2023-07-30 09:32:41 -07:00
Justine Tunney
18bb5888e1
Make more fixes and improvements
- Remove PAGESIZE constant
- Fix realloc() documentation
- Fix ttyname_r() error reporting
- Make forking more reliable on Windows
- Make execvp() a few microseconds faster
- Make system() a few microseconds faster
- Tighten up the socket-related magic numbers
- Loosen restrictions on mmap() offset alignment
- Improve GetProgramExecutableName() with getenv("_")
- Use mkstemp() as basis for mktemp(), tmpfile(), tmpfd()
- Fix flakes in pthread_cancel_test, unix_test, fork_test
- Fix recently introduced futex stack overflow regression
- Let sockets be passed as stdio to subprocesses on Windows
- Improve security of bind() on Windows w/ SO_EXCLUSIVEADDRUSE
2023-07-29 18:44:15 -07:00
Justine Tunney
7e0a09feec
Mint APE Loader v1.5
This change ports APE Loader to Linux AARCH64, so that Raspberry Pi
users can run programs like redbean, without the executable needing
to modify itself. Progress has also slipped into this change on the
issue of making progress better conforming to user expectations and
industry standards regarding which symbols we're allowed to declare
2023-07-26 13:54:49 -07:00
Justine Tunney
0a24b4fc3c
Clean up more code
The *NSYNC linked list API is good enough that it deserves to be part of
the C libray, so this change writes an improved version of it which uses
that offsetof() trick from the Linux Kernel. We vendor all of the *NSYNC
tests in third_party which helped confirm the needed refactoring is safe

This change also deletes more old code that didn't pan out. My goal here
is to work towards a vision where the Cosmopolitan core libraries become
less experimental and more focused on curation. This better reflects the
current level of quality we've managed to achieve.
2023-07-06 08:03:24 -07:00
Justine Tunney
73c0faa1b5
Remove some dead code 2023-07-03 02:48:29 -07:00
Justine Tunney
d7c79f43ef
Clean up more code
- Found some bugs in LLVM compiler-rt library
- The useless LIBC_STUBS package is now deleted
- Improve the overflow checking story even further
- Get chibicc tests working in MODE=dbg mode again
- The libc/isystem/ headers now have correctly named guards
2023-06-18 01:00:05 -07:00
Justine Tunney
c3440d040c
Make improvements
- More timspec_*() and timeval_*() APIs have been introduced.
- The copyfd() function is now simplified thanks to POSIX rules.
- More Cosmo-specific APIs have been moved behind the COSMO define.
- The setitimer() polyfill for Windows NT is now much higher quality.
- Fixed build error for MODE=aarch64 due to -mstringop-strategy=loop.
- This change introduces `make MODE=nox87 toolchain` which makes it
  possible to build programs using your cosmocc toolchain that don't
  have legacy fpu instructions. This is useful, for example, if you
  want to have a ~22kb tinier blink virtual machine.
2023-06-15 14:50:53 -07:00
Justine Tunney
daf4454a06
Validate privileged code relationships
- Work towards improving non-optimized build support
- Introduce MODE=zero which is -O0 without ASAN/UBSAN
- Use system GCC when ~/.cosmo.mk has USE_SYSTEM_TOOLCHAIN=1
- Have package.com check .privileged code doesn't call non-privileged
2023-06-08 04:38:06 -07:00
Justine Tunney
eb40cb371d
Get --ftrace working on aarch64
This change implements a new approach to function call logging, that's
based on the GCC flag: -fpatchable-function-entry. Read the commentary
in build/config.mk to learn how it works.
2023-06-05 23:35:31 -07:00
Justine Tunney
39f20dbb13
Upgrade to Cosmopolitan GCC 11.2.0 for x86_64 2023-06-05 02:06:18 -07:00
Justine Tunney
bcf9af94bf
Get threads working well on MacOS Arm64
- Now using 10x better GCD semaphores
- We now generate Linux-like thread ids
- We now use fast system clock / sleep libraries
- The APE M1 loader now generates Linux-like stacks
2023-06-04 01:57:10 -07:00
Justine Tunney
210187cf77
Perform some code cleanup 2023-05-15 16:32:10 -07:00
Justine Tunney
86d9323a43
Remove sys_getrandom() on NetBSD
This fixes an apparent regression caused by
3f0bcdc3ef where getrandom() on NetBSD 9.2
doesn't appear to work; ktrace oddly reports:

    1446      1 .ape     CALL  #91 (unimplemented getdopt)
    1446      1 .ape     RET   #91 (unimplemented getdopt) -1 errno 78
    Function not implemented
    1446      1 .ape     PSIG  SIGSYS SIG_DFL: code=SI_NOINFO
2023-05-10 04:20:47 -07:00
Justine Tunney
3da887c58f
Introduce CPUID detection for Blink 2022-12-17 00:38:07 -08:00
Justine Tunney
f2af97711b
Make improvements
- Improve compatibility with Blink virtual machine
- Add non-POSIX APIs for joining threads and signal masks
- Never ever use anything except 32-bit integers for atomics
- Add some `#undef` statements to workaround `ctags` problems
2022-11-10 21:52:47 -08:00
Justine Tunney
b407327972
Make fixes and improvements
- clock_nanosleep() is now much faster on OpenBSD and NetBSD
- Thread joining is now much faster on NetBSD
- FreeBSD timestamps are now more accurate
- Thread spawning now goes faster on XNU
- Clean up the clone() code
2022-11-08 10:11:46 -08:00
Justine Tunney
c995838e5c
Make improvements
- Clean up sigaction() code
- Add a port scanner example
- Introduce a ParseCidr() API
- Clean up our futex abstraction code
- Fix a harmless integer overflow in ParseIp()
- Use kernel semaphores on NetBSD to make threads much faster
2022-11-07 02:26:06 -08:00
Justine Tunney
3f0bcdc3ef
Improve cancellations, randomness, and time
- Exhaustively document cancellation points
- Rename SIGCANCEL to SIGTHR just like BSDs
- Further improve POSIX thread cancellations
- Ensure asynchronous cancellations work correctly
- Elevate the quality of getrandom() and getentropy()
- Make futexes cancel correctly on OpenBSD 6.x and 7.x
- Add reboot.com and shutdown.com to examples directory
- Remove underscore prefix from awesome timespec_*() APIs
- Create assertions that help verify our cancellation points
- Remove bad timespec APIs (cmp generalizes eq/ne/gt/gte/lt/lte)
2022-11-05 23:45:32 -07:00
Justine Tunney
022536cab6
Make futexes cancellable by pthreads 2022-11-04 18:36:34 -07:00
Justine Tunney
2278327eba
Implement support for POSIX thread cancellations
This change makes some miracle modifications to the System Five system
call support, which lets us have safe, correct, and atomic handling of
thread cancellations. It all turned out to be cheaper than anticipated
because it wasn't necessary to modify the system call veneers. We were
able to encode the cancellability of each system call into the magnums
found in libc/sysv/syscalls.sh. Since cancellations are so waq, we are
also supporting a lovely Musl Libc mask feature for raising ECANCELED.
2022-11-04 01:04:43 -07:00
Justine Tunney
60cb435cb4
Implement pthread_atfork()
If threads are being used, then fork() will now acquire and release and
runtime locks so that fork() may be safely used from threads. This also
makes vfork() thread safe, because pthread mutexes will do nothing when
the process is a child of vfork(). More torture tests have been written
to confirm this all works like a charm. Additionally:

- Invent hexpcpy() api
- Rename nsync_malloc_() to kmalloc()
- Complete posix named semaphore implementation
- Make pthread_create() asynchronous signal safe
- Add rm, rmdir, and touch to command interpreter builtins
- Invent sigisprecious() and modify sigset functions to use it
- Add unit tests for posix_spawn() attributes and fix its bugs

One unresolved problem is the reclaiming of *NSYNC waiter memory in the
forked child processes, within apps which have threads waiting on locks
2022-10-16 12:25:13 -07:00
Justine Tunney
8111462789
Add posix semaphores support
There's still some bugs to work out on Windows and OpenBSD.
2022-10-14 09:21:02 -07:00
Justine Tunney
997ce29ddc
Elevate Windows production worthiness
- SQLite file locking now works on Windows
- SQLite will now use fdatasync() on non-Apple platforms
- Fix Ctrl-C handler on Windows to not crash with TLS
- Signals now work in multithreaded apps on Windows
- fcntl() will now accurately report EINVAL errors
- fcntl() now has excellent --strace logging
- Token bucket replenish now go 100x faster
- *NSYNC cancellations now work on Windows
- Support closefrom() on NetBSD
2022-10-13 13:44:41 -07:00
Justine Tunney
9b7c8db846
Perform some code maintenance
- Change IDT code so kprintf() isn't mandatory dependency
- Document current intentions around pthread_cancel()
- Make _npassert() an _unassert() in MODE=tiny
2022-10-09 13:00:46 -07:00
Justine Tunney
672ccda37c
Clean up some sleep code 2022-10-08 03:00:48 -07:00
Justine Tunney
9849b4c7ba
Add *NSYNC unit test suite
This change also fixes the clock_nanosleep() api and polyfills futexes
on Windows, Mac, and NetBSD using exponential backoff.
2022-10-07 21:34:15 -07:00
Justine Tunney
59ac141e49
Improve the affinity system calls 2022-10-06 15:08:29 -07:00
Justine Tunney
7822917fc2
Add shared memory apis to redbean
You can now do things like implement mutexes using futexes in your
redbean lua code. This provides the fastest possible inter-process
communication for your production systems when SQLite alone as ipc
or things like pipes aren't sufficient.
2022-10-06 04:55:26 -07:00
Justine Tunney
b75a4654cf
Introduce clock_nanosleep() 2022-10-05 06:37:15 -07:00
Justine Tunney
91e167caaf
Rewrite IPv4 Turf War backend
It can now handle 240k SQLite write QPS at 3ms 99 percentile latency.
We're still working out the kinks since it's brand new. But we've got
this running in production already!
2022-10-03 08:23:54 -07:00
Justine Tunney
7549a5755e
Support futexes on FreeBSD 2022-10-02 11:57:13 -07:00
Justine Tunney
134ffee519
Change support vector to Windows 8+
Doing this makes binaries tinier, since we don't need to have all the
extra code for supporting a 32-bit address space. It also benefits us
because we're able to use WIN32 futexes, which makes locking simpler.

b69f3d2488 is what officially ended our
Windows 7 support. This change is merely a formalization. You can use
old versions of Cosmo now and forevermore if you need Windows 7 since
our repository is hermetic and vendors all its dependencies.

Won't fix #617
2022-09-15 03:55:05 -07:00
Justine Tunney
654ceaba7d
Clean up threading code some more 2022-09-13 20:17:34 -07:00
Justine Tunney
22b63d0b98
Add *NSYNC to libc/isystem 2022-09-13 01:47:12 -07:00
Justine Tunney
6f7d0cb1c3
Pay off more technical debt
This makes breaking changes to add underscores to many non-standard
function names provided by the c library. MODE=tiny is now tinier and
we now use smaller locks that are better for tiny apps in this mode.
Some headers have been renamed to be in the same folder as the build
package, so it'll be easier to know which build dependency is needed.
Certain old misguided interfaces have been removed. Intel intrinsics
headers are now listed in libc/isystem (but not in the amalgamation)
to help further improve open source compatibility. Header complexity
has also been reduced. Lastly, more shell scripts are now available.
2022-09-12 23:36:56 -07:00
Justine Tunney
b69f3d2488
Optimize memory layout 2022-09-12 04:26:52 -07:00
Justine Tunney
9b89a7c51d
Add *NSYNC mu_test 2022-09-11 18:56:29 -07:00
Justine Tunney
b5cb71ab84
Use *NSYNC for POSIX threads locking APIs
Condition variables, barriers, and r/w locks now work very well.
2022-09-11 11:04:50 -07:00