* Allow clone where both the child function and stack are null. It's
obviously wrong to ask to call a function without a stack, but it's not
necessarily wrong to supply no stack if you're also not supplying a
function.
* Reimplement fork in terms of the clone function, rather than using the
clone system call directly.
This is intended as a step towards enabling use of pid namespaces.
Change-Id: I03c89bd1dc540d8b4ed1c8fdf6644290744b9e91
The clone syscall accepts NULL child stacks, interpreting this to mean
the child gets a copy of the parent's stack with copy-on-write
semantics. However clone(2) is explicitly documented to treat this an
an error.
"Fortunately" every architecture's __bionic_clone implementation pushes
something onto the child stack before making the clone syscall. So we
know fixing this won't break legacy apps, because any app that tried
using a NULL child stack would have died with SIGSEGV.
This change fixes the LTP clone04 testcase.
Change-Id: I663b34f34bc8dad2aa405c46e4eed4418cccca0d
Signed-off-by: Greg Hackmann <ghackmann@google.com>
I've also switched some tests to be positive rather than negative,
because !defined is slightly harder to reason about and there are
only two cases: bionic and glibc.
Change-Id: I8d3ac40420ca5aead3e88c69cf293f267273c8ef
clone(2) is the public symbol.
Also switch a test from __bionic_clone to clone; testing public API
means the test now works on glibc too.
Change-Id: If59def26a00c3afadb8a6cf9442094c35a59ffde
There is a known bug running clone with the CLONE_VM flag, so for host
create an empty test.
Change the expected output of the stdio test for a glibc difference.
Change the pause test to use ScopedSignalHandler to setup/restore the SIGALRM
handler.
After this, running bionic-unit-tests-glibc passes for all tests.
Bug: 11389824
Change-Id: Ib304eae4164115835a54991dfdca5821ecc3db5e
