When adding a callback to an FD stream, we take an extra reference
on the virStreamPtr instance. We forgot to registered a free function
with the callback, so when the callback was removed, the extra
reference held on virStreamPtr was not released.
* src/fdstream.c: Use a free callback to release reference on
virStreamPtr when removing callback
If a callback being invoked from a stream issues a virStreamAbort
operation, the stream data will be free'd but the callback will
then still try to use this. Delay free'ing of the stream data when
a callback is dispatching
* src/fdstream.c: Delay stream free when callback is active
Since we virEventRegisterDefaultImpl is now a public API, callers need
a way to invoke the default registered Handle and Timeout functions. We
already have general functions for these internally, so promote
them to the public API.
v2:
Actually add APIs to libvirt.h
virFDStreamClose used a mutex after it was freed, and failed
to destroy that mutex on its last use.
* src/fdstream.c (virFDStreamFree): Inline into sole caller...
(virFDStreamClose): ...to avoid use-after-free and leak.
Reported by Matthias Bolte.
This is needed if we want to transfer a temporary file. If the
transfer is done with iohelper, we might run into a race condition,
where we unlink() file before iohelper is executed.
* src/fdstream.c, src/fdstream.h,
src/util/iohelper.c: Add new option
* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c,
src/storage/storage_driver.c, src/uml/uml_driver.c,
src/xen/xen_driver.c: Expand existing function calls
The O_NONBLOCK flag doesn't work as desired on plain files
or block devices. Introduce an I/O helper program that does
the blocking I/O operations, communicating over a pipe that
can support O_NONBLOCK
* src/fdstream.c, src/fdstream.h: Add non-blocking I/O
on plain files/block devices
* src/Makefile.am, src/util/iohelper.c: I/O helper program
* src/qemu/qemu_driver.c, src/lxc/lxc_driver.c,
src/uml/uml_driver.c, src/xen/xen_driver.c: Update for
streams API change
* src/fdstream.c (virFDStreamOpenFile, virFDStreamCreateFile):
Use VIR_FORCE_CLOSE instead of close.
* tests/commandtest.c (mymain): Likewise.
* tools/virsh.c (editFile): Use virCommand instead of system.
* src/util/util.c (__virExec): Special case preservation of std
file descriptors to child.
To avoid the need for duplicating implementations of virStream
drivers, provide a generic implementation that can handle any
FD based stream. This code is copied from the existing impl
in the QEMU driver, with the locking moved into the stream
impl, and addition of a read callback
The FD stream code will refuse to operate on regular files or
block devices, since those can't report EAGAIN properly when
they would block on I/O
* include/libvirt/virterror.h, include/libvirt/virterror.h: Add
VIR_FROM_STREAM error domain
* src/qemu/qemu_driver.c: Remove code obsoleted by the new
generic streams driver.
* src/fdstream.h, src/fdstream.c, src/fdstream.c,
src/libvirt_private.syms: Generic reusable FD based streams
