Currently, in cosmopolitan, there is no handling of the current rounding
mode for long double conversions, such that round-to-nearest gets always
used, regardless of the current rounding mode. %Le also improperly calls
gdtoa with a too small precision (which led to relatively similar bugs).
This patch fixes these issues, in particular by modifying the FPI object
passed to gdtoa such that it is modifiable (so that __fmt can adjust its
rounding field to correspond to FLT_ROUNDS (note that this is not needed
for dtoa, which checks FLT_ROUNDS directly)) and ors STRTOG_Neg into the
kind field in both of the __fmt_dfpbits and __fmt_ldfpbits functions, as
the gdtoa function also depends on it to be able to accurately round any
negative arguments. The change to kind also requires a few other changes
to make sure kind's upper bits (which include STRTOG_Neg) are masked off
when attempting to only examine the lower bits' value. Furthermore, this
patch also makes exactly one change in gdtoa, which appears to be needed
to fix rounding issues with FE_TOWARDZERO (this seems like a gdtoa bug).
The patch also adds a few tests for these issues, along with also taking
the opportunity to clean up some of the previous tests to do the asserts
in the right order (i.e. with the first argument as the expected result,
and the second one being used as the value that it is compared against).
Before this commit, cosmopolitan had some issues with handling arguments
of 0 and signs, such as returning an incorrect sign when the input value
== -0.0, and incorrectly handling ndigit == 0 on fcvt (ndigit determines
the amount of digits *after* the radix character on fcvt, thus the parts
before it still must be outputted before fcvt's job is completely done).
This patch fixes these issues, and adds tests with corresponding inputs.
This change introduces comsoaudio v1. We're using a new strategy when it
comes to dynamic linking of dso files and building miniaudio device code
which I think will be fast and stable in the long run. You now have your
choice of reading/writing to the internal ring buffer abstraction or you
can specify a device-driven callback function instead. It's now possible
to not open the microphone when you don't need it since touching the mic
causes security popups to happen. The DLL is now built statically, so it
only needs to depend on kernel32. Our NES terminal emulator now uses the
cosmoaudio library and is confirmed to be working on Windows, Mac, Linux
The C Standard specifies that, when a conversion specification specifies
a conversion specifier of n, the type of the passed pointer is specified
by the length modifier (if any), i.e. that e.g. the argument for %hhn is
of type signed char *, but Cosmopolitan currently does not handle this -
instead always simply assuming that the pointer always points to an int.
This patch implements, and tests, length modifiers with the n conversion
specifier, with the tests testing all of the available length modifiers.
This change gets printvideo working on aarch64. Performance improvements
have been introduced for magikarp decimation on aarch64. The last of the
old portable x86 intrinsics library is gone, but it still lives in Blink
The worst issue I had with consts.sh for clock_gettime is how it defined
too many clocks. So I looked into these clocks all day to figure out how
how they overlap in functionality. I discovered counter-intuitive things
such as how CLOCK_MONOTONIC should be CLOCK_UPTIME on MacOS and BSD, and
that CLOCK_BOOTTIME should be CLOCK_MONOTONIC on MacOS / BSD. Windows 10
also has some incredible new APIs, that let us simplify clock_gettime().
- Linux CLOCK_REALTIME -> GetSystemTimePreciseAsFileTime()
- Linux CLOCK_MONOTONIC -> QueryUnbiasedInterruptTimePrecise()
- Linux CLOCK_MONOTONIC_RAW -> QueryUnbiasedInterruptTimePrecise()
- Linux CLOCK_REALTIME_COARSE -> GetSystemTimeAsFileTime()
- Linux CLOCK_MONOTONIC_COARSE -> QueryUnbiasedInterruptTime()
- Linux CLOCK_BOOTTIME -> QueryInterruptTimePrecise()
Documentation on the clock crew has been added to clock_gettime() in the
docstring and in redbean's documentation too. You can read that to learn
interesting facts about eight essential clocks that survived this purge.
This is original research you will not find on Google, OpenAI, or Claude
I've tested this change by porting *NSYNC to become fully clock agnostic
since it has extensive tests for spotting irregularities in time. I have
also included these tests in the default build so they no longer need to
be run manually. Both CLOCK_REALTIME and CLOCK_MONOTONIC are good across
the entire amd64 and arm64 test fleets.
POSIX specifies the C conversion specifier as being "equivalent to %lc",
i.e. printf("%C", arg) is equivalent in behaviour to printf("%lc", arg).
This patch implements this conversion specifier, and adds a test for it,
alongside another test, which ensures that va_arg uses the correct size,
even though we set signbit to 63 in the code (which one might think will
result in the wrong size of argument being va_arg-ed, but having signbit
set to 63 is in fact what __fmt_stoa expects and is a requirement for it
properly formatting the wchar_t argument - this does not result in wrong
usage of va_arg because the implementation of the c conversion specifier
(which the implementation of the C conversion specifier fallsthrough to)
always calls va_arg with an argument type of int, to avoid the very same
bug occuring with %lc, as the l length modifier also sets signbit to 63)
This is one of the few POSIX APIs that was missing. It lets you choose a
monotonic clock for your condition variables. This might improve perf on
some platforms. It might also grant more flexibility with NTP configs. I
know Qt is one project that believes it needs this. To introduce this, I
needed to change some the *NSYNC APIs, to support passing a clock param.
There's also new benchmarks, demonstrating Cosmopolitan's supremacy over
many libc implementations when it comes to mutex performance. Cygwin has
an alarmingly bad pthread_mutex_t implementation. It is so bad that they
would have been significantly better off if they'd used naive spinlocks.
On Windows file system tools like `ls` would print errors when they find
things like WSL symlinks, which can't be read by WIN32. I don't know how
they got on my hard drive but this change ensures Cosmo will handle them
more gracefully. If a reparse point can't be followed, then fstatat will
return information about the link itself. If readlink encounters reparse
points that are WIN32 symlinks, then it'll log more helpful details when
using MODE=dbg (a.k.a. cosmocc -mdbg). Speaking of which, this change is
also going to help you troubleshoot locks; when you build your app using
the cosmocc -mdbg flag your --strace logs will now show lock acquisition
While we have always licked glibc and musl libc on gnu/systemd sadly the
Apple Libc implementation of pthread_mutex_t is better than ours. It may
be due to how the XNU kernel and M2 microprocessor are in league when it
comes to scheduling processes and the NSYNC behavior is being penalized.
We can solve this by leaning more heavily on ulock using Drepper's algo.
It's kind of ironic that Linux's official mutexes work terribly on Linux
but almost as good as Apple Libc if used on MacOS.
poll() and select() now delegate to ppoll() and pselect() for assurances
that both polyfill implementations are correct and well-tested. Poll now
polyfills XNU and BSD quirks re: the hanndling of POLLNVAL and the other
similar status flags. This change resolves a misunderstanding concerning
how select(exceptfds) is intended to map to POLPRI. We now use E2BIG for
bouncing requests that exceed the 64 handle limit on Windows. With pipes
and consoles on Windows our poll impl will now report POLLHUP correctly.
Issues with Windows path generation have been fixed. For example, it was
problematic on Windows to say: posix_spawn_file_actions_addchdir_np("/")
due to the need to un-UNC paths in some additional places. Calling fstat
on UNC style volume path handles will now work. posix_spawn now supports
simulating the opening of /dev/null and other special paths on Windows.
Cosmopolitan no longer defines epoll(). I think wepoll is a nice project
for using epoll() on Windows socket handles. However we need generalized
file descriptor support to make epoll() for Windows work well enough for
inclusion in a C library. It's also not worth having epoll() if we can't
get it to work on XNU and BSD OSes which provide different abstractions.
Even epoll() on Linux isn't that great of an abstraction since it's full
of footguns. Last time I tried to get it to be useful I had little luck.
Considering how long it took to get poll() and select() to be consistent
across platforms, we really have no business claiming to have epoll too.
While it'd be nice to have fully implemented, the only software that use
epoll() are event i/o libraries used by things like nodejs. Event i/o is
not the best paradigm for handling i/o; threads make so much more sense.
This change fixes an issue with all system calls ending with *at(), when
the caller passes `dirfd != AT_FDCWD` and an absolute path. It's because
the old code was turning paths like C:\bin\ls into \\C:\bin\ls\C:\bin\ls
after being converted from paths like /C/bin/ls. I noticed this when the
Emacs dired mode stopped working. It's unclear if it's a regression with
Cosmopolitan Libc or if this was introduced by the Emacs v29 upgrade. It
also impacted posix_spawn() for which a newly minted example now exists.
Cosmopolitan's printf-family functions will currently crash if one tries
formatting a floating point number with a larger precision (large enough
that gdtoa attempts to allocate memory to format the number) while under
memory pressure (i.e. when malloc fails) because gdtoa fails to check if
malloc fails.
The added tests (which would previously crash under cosmopolitan without
this patch) show how to reproduce the issue.
This patch fixes this, and adds the aforementioned tests.
This method is supposed to give equivalence iff two shared pointers both
own the same object, even if they point to different addresses. We can't
control the exact order of the control blocks in memory, so the test can
only check that this equivalence/non-equivalence relationship holds, and
this is in fact all that it should check.
I'd previously introduced a bunch of small wrappers around the class and
functions under test to avoid excessive cpp use, but we can achieve this
more expediently with simple using-declarations. This also cuts out some
over-specified tests (e.g. there's no reason a stateful deleter wouldn't
compile.)
Cosmopolitan's printf-family functions currently very poorly handle
being passed a long double infinity.
For instance, a program such as:
```cpp
#include <stdio.h>
int main()
{
printf("%f\n", 1.0 / 0.0);
printf("%Lf\n", 1.0L / 0.0L);
printf("%e\n", 1.0 / 0.0);
printf("%Le\n", 1.0L / 0.0L);
printf("%g\n", 1.0 / 0.0);
printf("%Lg\n", 1.0L / 0.0L);
}
```
will currently output the following:
```
inf
0.000000[followed by 32763 more zeros]
inf
N.aN0000e-32769
inf
N.aNe-32769
```
when the correct expected output would be:
```
inf
inf
inf
inf
inf
inf
```
This patch fixes this, and adds tests for the behavior.
- wcsstr() is now linearly complex
- strstr16() is now linearly complex
- strstr() is now vectorized on aarch64 (10x)
- strstr() now uses KMP on pathological cases
- memmem() is now vectorized on aarch64 (10x)
- memmem() now uses KMP on pathological cases
- Disable shared_ptr::owner_before until fixed
- Make iswlower(), iswupper() consistent with glibc
- Remove figure space from iswspace() implementation
- Include line and paragraph separator in iswcntrl()
- Use Musl wcwidth(), iswalpha(), iswpunct(), towlower(), towupper()
This change switches c++ exception handling from sjlj to standard dwarf.
It's needed because clang for aarch64 doesn't support sjlj. It turns out
that libunwind had a bare-metal configuration that made this easy to do.
This change gets the new experimental cosmocc -mclang flag in a state of
working so well that it can now be used to build all of llamafile and it
goes 3x faster in terms of build latency, without trading away any perf.
The int_fast16_t and int_fast32_t types are now always defined as 32-bit
in the interest of having more abi consistency between cosmocc -mgcc and
-mclang mode.
The server was originally written before I implemented support for POSIX
thread cancelation. We now use standard pthreads APIs instead of talking
directly to *NSYNC. This means we're no longer using *NSYNC notes, which
aren't as good as the POSIX thread cancelation support I added to *NSYNC
which was only made possible by making *NSYNC part of libc. I believe it
will solve a crash we observed recently with ipv4.games, courtesy of the
individual who goes by the hacker alias Lambro.
This was suppressed recently and it's the worst possible idea when doing
greenfield software development with C. I'm so sorry it slipped through.
If the C standards committee was smart they would change the standard so
that implicit int becomes implicit long. Then problems such as this will
never occur and we could even use traditional C safely if we wanted too.
C++ code compiles very slowly with cosmocc, possibly because we're using
LLVM LIBCXX with GCC, and LLVM doesn't work as hard to make GCC go fast.
Therefore, it should be possible, to ask cosmocc to favor Clang over GCC
under the hood. On llamafile, my intention's to use this to make certain
files, e.g. llama.cpp/common.cpp, go from taking 17 seconds to 5 seconds
This new -mclang flag isn't ready for production yet since there's still
the question of how to get Clang to generate SJLJ exception code. If you
use this, then it's recommended you also pass -fno-exceptions.
The tradeoff is we're adding a 121mb binary to the cosmocc distribution.
There are no plans as of yet to fully migrate to Clang since GCC is very
good and has always treated us well.
This is believed to fix a crash, that's possible in nsync_waiter_free_()
when you call pthread_cond_timedwait(), or nsync_cv_wait_with_deadline()
where an assertion can fail. Thanks ipv4.games for helping me find this!
