This change introduces a new deadlock detector for Cosmo's POSIX threads
implementation. Error check mutexes will now track a DAG of nested locks
and report EDEADLK when a deadlock is theoretically possible. These will
occur rarely, but it's important for production hardening your code. You
don't even need to change your mutexes to use the POSIX error check mode
because `cosmocc -mdbg` will enable error checking on mutexes by default
globally. When cycles are found, an error message showing your demangled
symbols describing the strongly connected component are printed and then
the SIGTRAP is raised, which means you'll also get a backtrace if you're
using ShowCrashReports() too. This new error checker is so low-level and
so pure that it's able to verify the relationships of every libc runtime
lock, including those locks upon which the mutex implementation depends.
The (uppercase) B conversion specifier is specified by the C standard to
have the same behavior as the (lowercase) b conversion specifier, except
that whenever the # flag is used, the (uppercase) B conversion specifier
alters a nonzero result by prefixing it with "0B", instead of with "0b".
This commit adds this conversion specifier alongside a few tests for it.
The C standard specifies that, upon handling the a conversion specifier,
the argument is converted to a string in which "there is one hexadecimal
digit (which is nonzero [...]) before the decimal-point character", this
being a requirement which cosmopolitan does not currently always handle,
sometimes printing numbers like "0x0.1p+5", where a correct output would
have been e.g. "0x1.0p+1" (despite both representing the same value, the
first one illegally has a '0' digit before the decimal-point character).
The C standard indicates that when processing the a conversion specifier
"if the precision is zero *and* the # flag is not specified, no decimal-
point character appears.". This means that __fmt needs to ensure that it
prints the decimal-point character not only when the precision is non-0,
but also when the # flag is specified - cosmopolitan currently does not.
This patch fixes this, along with adding a few tests for this behaviour.
The a conversion specifier to printf had some issues w.r.t. rounding, in
particular in edge cases w.r.t. "to nearest, ties to even" rounding (for
instance, "%.1a" with 0x1.78p+4 outputted 0x1.7p+4 instead of 0x1.8p+4).
This patch fixes this and adds several tests w.r.t ties to even rounding
POSIX specifies the <apostrophe> flag character for printf as formatting
decimal conversions with the thousands' grouping characters specified by
the current locale. Given that cosmopolitan currently has no support for
obtaining the locale's grouping character, all that is required (when in
the C/POSIX locale) for supporting this flag is ignoring it, and as it's
already used to indicate quoting (for non-decimal conversions), all that
has to be done is to avoid having it be an alias for the <space> flag so
that decimal conversions don't accidentally behave as though the <space>
flag has also been specified whenever the <apostrophe> flag is utilized.
This patch adds this flag, as described above, along with a test for it.
Hexadecimal printing of floating-point numbers in cosmopolitan (that is,
using the the conversion specifier) is improved to have correct rounding
of results in rounding modes other than the default one (ie. FE_NEAREST)
This commit fixes that, and adds tests for the change (note that there's
still some rounding issues with the a conversion specifier in general in
relatively rare cases (that is without non-default rounding modes) where
I've left commented-out tests for anyone interested in improving it more
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.
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.
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)
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.
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.
We now have implement all of Musl's localization code, the same way that
Musl implements localization. You may need setlocale(LC_ALL, "C.UTF-8"),
just in case anything stops working as expected.
It's now possible to create thousands of thousands of sparse independent
memory mappings, without any slowdown. The memory manager is better with
tracking memory protection now, particularly on Windows in a precise way
that can be restored during fork(). You now have the highest quality mem
manager possible. It's even better than some OSes like XNU, where mmap()
is implemented as an O(n) operation which means sadly things aren't much
improved over there. With this change the llamafile HTTP server endpoint
at /tokenize with a prompt of 50 tokens is now able to handle 2.6m r/sec
This fixes a regression in mmap(MAP_FIXED) on Windows caused by a recent
revision. This change also fixes ZipOS so it no longer needs a MAP_FIXED
mapping to open files from the PKZIP store. The memory mapping mutex was
implemented incorrectly earlier which meant that ftrace and strace could
cause cause crashes. This lock and other recursive mutexes are rewritten
so that it should be provable that recursive mutexes in cosmopolitan are
asynchronous signal safe.
It hasn't been helpful enough to be justify the maintenance burden. What
actually does help is mprotect(), kprintf(), --ftrace and --strace which
can always be counted upon to work correctly. We aren't losing much with
this change. Support for ASAN on AARCH64 was never implemented. Applying
ASAN to the core libc runtimes was disabled many months ago. If there is
some way to have an ASAN runtime for user programs that is less invasive
we can potentially consider reintroducing support. But now is premature.
Actually Portable Executable now supports Android. Cosmo's old mmap code
required a 47 bit address space. The new implementation is very agnostic
and supports both smaller address spaces (e.g. embedded) and even modern
56-bit PML5T paging for x86 which finally came true on Zen4 Threadripper
Cosmopolitan no longer requires UNIX systems to observe the Windows 64kb
granularity; i.e. sysconf(_SC_PAGE_SIZE) will now report the host native
page size. This fixes a longstanding POSIX conformance issue, concerning
file mappings that overlap the end of file. Other aspects of conformance
have been improved too, such as the subtleties of address assignment and
and the various subtleties surrounding MAP_FIXED and MAP_FIXED_NOREPLACE
On Windows, mappings larger than 100 megabytes won't be broken down into
thousands of independent 64kb mappings. Support for MAP_STACK is removed
by this change; please use NewCosmoStack() instead.
Stack overflow avoidance is now being implemented using the POSIX thread
APIs. Please use GetStackBottom() and GetStackAddr(), instead of the old
error-prone GetStackAddr() and HaveStackMemory() APIs which are removed.
🚨 clang-format changes output per version!
This is with version 19.0.0. The modifications seem to be fixing the old
version’s errors - mainly involving omitted whitespace around binary ops
and inserted whitespace between goto labels and colons (if followed by a
curly brace.)
Also fixes a few mistakes made by e.g. someone (ahem) forgetting to pass
his ctl/string.h modifications through it.
We should add this to .git-blame-ignore-revs once we have its final hash
on master.
Microsoft caused some very gentle breakages for Cosmopolitan. They
removed the version information from the PEB which caused uname to
report WINDOWS 0.0.0. We should have called GetVersionExW but that
doesn't really exist anymore either. Windows policy is now to give
whatever version we used in ape/ape.S. Windows8 has been EOL since
2023-01-10 so lets avoid our modern executables being relegated to
legacy infrastructure. Requiring Windows 10+ going forward lets us
remove runtime compatibility bloat from the codebase. Further note
Cosmopolitan maintains a Windows Vista branch on GitHub, so anyone
preferring the older versions, can still have a future with Cosmo.
Another neat thing this fixes is UTF-8 support in the console. The
changes Microsoft made broke the if statement that enabled UTF8 in
terminals. This explains why bug reports had broken arrows. In the
future this should be less of an issue, since the PEB code is gone
which means we more strictly conform to only Microsoft's WIN32 API
It's now possible to safely print C++ backtraces from signal handlers.
This symbol demangler doesn't need malloc, tls, or even static memory.
Additionally, this change makes it 2x faster and adds test cases. It's
almost as performant and accurate as the libcxxabi implementation now.
Cosmopolitan now supports 104 time zones. They're embedded inside any
binary that links the localtime() function. Doing so adds about 100kb
to the binary size. This change also gets time zones working properly
on Windows for the first time. It's not needed to have /etc/localtime
exist on Windows, since we can get this information from WIN32. We're
also now updated to the latest version of Paul Eggert's TZ library.
