ucontext implementation featuring glibc-compatible ABI
William Pitcock 4f190cc561
Merge pull request #10 from fabled/master
3 months ago
arch fix x86_64 register order for swapcontext 3 months ago
.gitignore build: add libucontext test program 8 months ago
LICENSE don't bother with glibc stuff afterall, kernel defines ABI to use 8 months ago
Makefile build: use -lucontext instead of libucontext.so in linker flags for test program 8 months ago
README.md README: we support s390x now 8 months ago
test_libucontext.c test_libucontext: explain the stack poisoning part 8 months ago

README.md

libucontext

libucontext is a library which provides the ucontext.h C API. Unlike other implementations, it faithfully follows the kernel process ABI when doing context swaps.

Notably, when combined with gcompat, it provides a fully compatible implementation of the ucontext functions that are ABI compatible with glibc.

supported architectures

Adding support for new architectures is easy, but you need to know assembly language to do it.

Right now these archs are supported and should work on bare metal:

  • x86
  • x86_64
  • armv6+ (arm)
  • aarch64
  • s390x

These archs require kernel assistance and use a syscall (the only assembly is the trampoline):

  • ppc
  • ppc64 (ELFv2 ABI spec only, ELFv1 not supported)

building

libucontext uses a simple makefile build system. You should define ARCH= at build time, otherwise the build system will attempt to guess using uname -m.

$ make ARCH=x86_64
$ make ARCH=x86_64 check
$ make ARCH=x86_64 DESTDIR=out install

support

libucontext is offered as part of the gcompat project. Accordingly, please address all questions and bug reports to gcompat@lists.adelielinux.org.