ucontext implementation featuring glibc-compatible ABI
 
 
 
 
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Bobby Bingham 8ea5f548b9 ppc64: fix makecontext with more than 8 parameters
The ELFv2 ABI used on PPC64 differs from the ELFv1 ABI used on PPC32 here.
On PPC64, once there are any parameters that need to be passed on the
stack, space needs to be reserved on the stack to pass all parameters.
Parameters 0-7 are still only passed by register, but if the callee needs
to spill them, it can use the stack space reserved for the corresponding
parameter to do so.
2019-04-05 14:18:20 -05:00
arch ppc64: fix makecontext with more than 8 parameters 2019-04-05 14:18:20 -05:00
.gitignore build: add libucontext test program 2018-01-30 03:53:04 +00:00
LICENSE don't bother with glibc stuff afterall, kernel defines ABI to use 2018-01-29 21:50:49 +00:00
Makefile build: use -lucontext instead of libucontext.so in linker flags for test program 2018-02-15 04:41:22 +00:00
README.md README: we support s390x now 2018-02-15 05:55:26 +00:00
test_libucontext.c test calls to getcontext without makecontext 2019-04-05 13:28:36 -05:00

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.