cosmopolitan/libc
Justine Tunney dd53f31147
Introduce post-linker that converts ELF to PE
If you build a static ELF executable in `ld -q` mode (which leaves rela
sections inside the binary) then you can run it through the elf2pe.com
program afterwards, which will turn it into a PE executable. We have a
new trick for defining WIN32 DLL imports in C without any assembly code.
This also achieves the optimally tiny and perfect PE binary structure.

We need this because it isn't possible to have a GNU ld linker script
generate a PE file where the virtual pointer and the file pointer can
drift apart. This post-linker can do that. One cool benefit is we can
now use a smaller 512-byte alignment in the file, and an even bigger
64kb alignment for the segment virtual addresses, and the executable
ends up being smaller.

Another program introduced by this change is pecheck.com which can do
extensive linting of PE static executables to help explain why Windows
won't load it.
2023-08-09 18:46:06 -07:00
..
calls Mint APE Loader 1.6 2023-08-09 00:27:26 -07:00
crt Fix breakages in Linux-only build modes 2023-07-09 19:51:44 -07:00
dns Perform inconsequential code cleanup 2023-08-07 20:24:50 -07:00
elf Introduce post-linker that converts ELF to PE 2023-08-09 18:46:06 -07:00
fmt Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
integral Restore missing cosmopolitan documentation on website 2023-07-30 11:07:53 -07:00
intrin Fix POLLIN|POLLOUT when together on Windows 2023-08-08 10:33:52 -07:00
isystem Make more fixes and improvements 2023-07-29 18:44:15 -07:00
log Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
mem Make more fixes and improvements 2023-07-29 18:44:15 -07:00
nexgen32e Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
nt Introduce post-linker that converts ELF to PE 2023-08-09 18:46:06 -07:00
runtime Improve Windows Console I/O 2023-08-08 05:44:40 -07:00
sock Improve Windows Console I/O 2023-08-08 05:44:40 -07:00
stdio Invent systemvpe() function 2023-08-09 00:27:55 -07:00
str Perform inconsequential code cleanup 2023-08-07 20:24:50 -07:00
sysv Make more fixes and improvements 2023-07-29 18:44:15 -07:00
testlib Make more fixes and improvements 2023-07-29 18:44:15 -07:00
thread Make more fixes and improvements 2023-07-29 18:44:15 -07:00
time Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
tinymath Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
vga Make improvements 2023-07-10 04:35:14 -07:00
x Make more fixes and improvements 2023-07-29 18:44:15 -07:00
zipos Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
ar.h Rewrite Cosmopolitan Ar 2023-07-02 10:19:16 -07:00
assert.h Mint APE Loader v1.5 2023-07-26 13:54:49 -07:00
atomic.h Optimize memory layout 2022-09-12 04:26:52 -07:00
complex.h Port a lot more code to AARCH64 2023-05-14 09:37:26 -07:00
cosmo.h Invent systemvpe() function 2023-08-09 00:27:55 -07:00
dce.h Validate privileged code relationships 2023-06-08 04:38:06 -07:00
disclaimer.inc
dos.internal.h Introduce #include <cosmo.h> to toolchain users 2023-06-09 18:03:05 -07:00
empty.s Do some basic build tuning 2023-05-10 04:20:46 -07:00
errno.h Incorporate more small improvements 2023-07-23 10:57:18 -07:00
imag.internal.h Remove evil constants from cosmopolitan.h 2022-12-17 00:42:45 -08:00
inttypes.h Fix inttypes.h FAST16 macros to have a correct definition (#791) 2023-03-29 00:19:40 -07:00
iso646.internal.h Add more missing C / C++ headers 2022-09-04 04:53:52 -07:00
libc.mk Make improvements 2023-07-10 04:35:14 -07:00
limits.h Improve cosmo's conformance to libc-test 2022-10-10 17:52:41 -07:00
literal.h Improve cosmo's conformance to libc-test 2022-10-10 17:52:41 -07:00
mach.internal.h Introduce #include <cosmo.h> to toolchain users 2023-06-09 18:03:05 -07:00
macho.internal.h Fiddle around with Mach-O 2023-05-20 04:13:49 -07:00
macros.internal.h Fix bugs in cosmocc toolchain 2023-06-08 23:44:03 -07:00
math.h Make more ML improvements 2023-05-16 08:07:23 -07:00
notice.inc
notice.internal.h
paths.h Embed cocmd.com interpreter for system() / open() 2022-10-02 15:29:57 -07:00
README.md Reformat libc README.md (#437) 2022-06-21 07:50:42 -07:00
stdalign.internal.h Add more missing C / C++ headers 2022-09-04 04:53:52 -07:00
stdckdint.h Perform inconsequential code cleanup 2023-08-07 20:24:50 -07:00
type2str.h Improve new C23 checked arithmetic feature 2023-06-16 15:32:18 -07:00
zip.internal.h Support symbol tables with arch specific name 2023-07-29 23:50:15 -07:00

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.