Allow to specify the ExecContext in a call to run_cmd(). This
effectively makes run_cmd() an thin wrapper around ExecContext.run(),
which is what's going to be used in the future. The wrapper is for
backwards-compatibility.
Signed-off-by: Jan Lindemann <jan@janware.com>
The code below lib.distro, as left behind by the previous commit, is
geared towards being directly used as a command-line API. This commit
introduces the abstract base class Distro, a proxy for
distribution-specific interactions. The proxy abstracts distro
specifics into an API with proper method prototypes, not
argparse.Namespace contents, and can thus be more easily driven by
arbitrary code.
The Distro class is initialized with a member variable of type
ExecContext, another new class introduced by this commit. It is
designed to abstract the communication channel to the distribution
instance. Currently only one specialization exists, Local, which
interacts with the distribution and root file system it is running
in, but is planned to be subclassed to support interaction via SSH,
serial, chroot, or chains thereof.
Signed-off-by: Jan Lindemann <jan@janware.com>
