These fixes allow libguestfs bindings to work with Python 3 (tested
with Python 3.2)
You can select which Python you compile against by doing:
PYTHON=python ./configure && make && make check
or:
PYTHON=python3 ./configure && make && make check
Release the Python global interpreter lock while running libguestfs
calls.
We don't release it around guestfs_create() because that is a short
call that just allocates memory. We do release it around
guestfs_close() since that is a potentially long-running (it can call
wait(2) amongst other things). We also release it around all the
other generated Python calls.
We don't yet support callbacks into Python code (ie. the new event
API). But when we do in future, we will need to also handle the GIL
around those callbacks.
This code is adapted from libvirt's python/typewrappers.h. Thanks to
Dan Berrange for showing us how to do this properly.
There was a lot of repeated code to map return types (eg. RErr)
to error cases (eg. -1 or NULL).
This commit introduces an error code type and two functions to
map return types to error codes and error codes to strings.
This allows generic "foo *bar" pointers to be passed to
library functions (not to daemon functions).
In the language bindings (except Perl) these are handled
as generic int64s with the assumption being that any
pointer can be converted to and from this. There is room
to add specific support for some pointer types in future
by specializing the match cases. However this is inherently
tricky because it depends on the implementation details of
other bindings (eg. to support virDomainPtr in OCaml depends
on the implementation details of the ocaml-libvirt project).
Perl is slightly different in that you have to supply a
typemap. Again this would depend on the implementation
detail of an external library unless you supplied a generic
typemap for int64.
This large commit changes the generator so that optional arguments
can be supported for functions.
The model for arguments (known as the "style") is changed from
(ret, args) to (ret, args, optargs) where optargs is a more limited
list of arguments.
One function has been added which takes optional arguments, it is
"add-drive-opts", modelled as:
(RErr, [String "filename"], #required
[Bool "readonly"; String "format"; String "iface"]) #optional
Note that this function is processed in the library (does not go over
the RPC protocol to the daemon). This has allowed us to simplify
the current implementation by omitting changes related to RPC or the
daemon, although we plan to add these at some point in the future.
From C this function can be called in 3 different ways as in these
examples:
guestfs_add_drive_opts (g, filename,
GUESTFS_ADD_DRIVE_OPTS_READONLY, 1,
GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
-1);
(the argument(s) between 'filename' and '-1' are the optional ones).
guestfs_add_drive_opts_va (g, filename, args);
where 'args' is a va_list. This works like the first version.
struct guestfs_add_drive_opts_argv optargs = {
.bitmask = GUESTFS_ADD_DRIVE_OPTS_READONLY_BITMASK,
.readonly = 1,
}
guestfs_add_drive_opts_argv (g, filename, &optargs);
This last form lets you construct lists of optional arguments, and
is used by guestfish and the language bindings.
In guestfish optional arguments are used like this:
add-drive-opts filename readonly:true
In OCaml these are mapped naturally to OCaml optional arguments, eg:
g#add_drive_opts ~readonly:true filename;
In Perl these are mapped to extra arguments, eg:
$g->add_drive_opts ($filename, readonly => 1);
In Python these are mapped to optional arguments, eg:
g.add_drive_opts ("file", readonly = 1, format = "qcow2")
In Ruby these are mapped to a final hash argument, eg:
g.add_drive_opts("file", {})
g.add_drive_opts("file", :readonly => 1)
g.add_drive_opts("file", :readonly => 1, :iface => "virtio")
In PHP these are mapped to extra parameters. This is not quite
accurate since you cannot omit arbitrary optional parameters, but
there's not much than can be done within the limitations of PHP
as a language.
Unimplemented in: Haskell, C#, Java.
'src/generator.ml' is no more. Instead the generator is logically
split up over many different source files.
Read generator/README for help and tips.
We compile the generator down to bytecode, not native code. This
means it will run more slowly, but is done for maximum portability.
