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) |
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.. | ||
calls | ||
crt | ||
dlopen | ||
elf | ||
fmt | ||
integral | ||
intrin | ||
irq | ||
isystem | ||
log | ||
mem | ||
nexgen32e | ||
nt | ||
proc | ||
runtime | ||
sock | ||
stdio | ||
str | ||
sysv | ||
testlib | ||
thread | ||
tinymath | ||
vga | ||
x | ||
ar.h | ||
assert.h | ||
atomic.h | ||
BUILD.mk | ||
complex.h | ||
cosmo.h | ||
ctype.h | ||
cxxabi.h | ||
dce.h | ||
dos.h | ||
empty.s | ||
errno.h | ||
imag.h | ||
inttypes.h | ||
iso646.h | ||
limits.h | ||
literal.h | ||
mach.h | ||
macho.h | ||
macros.h | ||
math.h | ||
paths.h | ||
README.md | ||
serialize.h | ||
stdalign.h | ||
stdbool.h | ||
stdckdint.h | ||
stdlib.h | ||
temp.h | ||
testlib-test.txt | ||
time.h | ||
unistd.h | ||
utime.h | ||
wctype.h | ||
zip.h |
Cosmopolitan Standard Library
This directory defines static archives defining functions, like
printf()
, mmap()
, win32, etc. Please note that the Cosmopolitan
build configuration doesn't link any C/C++ library dependencies
by default, so you still have the flexibility to choose the one
provided by your system. If you'd prefer Cosmopolitan, just add
$(LIBC)
and $(CRT)
to your linker arguments.
Your library is compromised of many bite-sized static archives. We use the checkdeps tool to guarantee that the contents of the archives are organized in a logical way that's easy to use with or without our makefile infrastructure, since there's no cyclic dependencies.
The Cosmopolitan Library exports only the most stable canonical
system calls for all supported operating systems, regardless of
which platform is used for compilation. We polyfill many of the
APIs, e.g. read()
, write()
so they work consistently everywhere
while other apis, e.g. CreateWindowEx()
, might only work on one
platform, in which case they become no-op functions on others.
Cosmopolitan polyfill wrappers will usually use the dollar sign naming convention, so they may be bypassed when necessary. This same convention is used when multiple implementations of string library and other performance-critical function are provided to allow Cosmopolitan to go fast on both old and newer computers.
We take an approach to configuration that relies heavily on the
compiler's dead code elimination pass (libc/dce.h
). Most of the
code is written so that, for example, folks not wanting support
for OpenBSD can flip a bit in SUPPORT_VECTOR
and that code will
be omitted from the build. The same is true for builds that are
tuned using -march=native
which effectively asks the library to
not include runtime support hooks for x86 processors older than
what you use.
Please note that, unlike Cygwin or MinGW, Cosmopolitan does not achieve broad support by bolting on a POSIX emulation layer. We do nothing more than (in most cases) stateless API translations that get you 90% of the way there in a fast lightweight manner. We therefore can't address some of the subtle differences, such as the nuances of absolute paths on Windows. Our approach could be compared to something more along the lines of, "the Russians just used a pencil to write in space", versus spending millions researching a pen like NASA.