Re: [PATCH 11/18] python: Use PyBytes converter for resource acquire API

[Amit Bawer]

the original check here is for rv != 0. and cleanup code checks the same.
if we want to change the rv checks for sanlock calls we probably should to
that in a separate patch, not related to py3 changes anyway.

On Mon, Jun 10, 2019 at 3:41 PM Pavel Bar  wrote:
> On Mon, Jun 3, 2019 at 11:31 PM Nir Soffer  wrote:
> > From: Amit Bawer
> >
> > Implications:
> > Py2 : no difference
> > Py3 : if used, only accept bytes for lockspace/resource name.
> >
> > python/sanlock.c | 35 ++++++++++++++++++-----------------
> >  1 file changed, 18 insertions(+), 17 deletions(-)
> >
> > diff --git a/python/sanlock.c b/python/sanlock.c
> > index c7518c6..7bdbd69 100644
> > --- a/python/sanlock.c
> > +++ b/python/sanlock.c
> > @@ -1028,39 +1028,39 @@ mode. The version is the version of the lease
> > that must be acquired or fail.\n\
> >  The disks must be in the format: [(path, offset), ... ]\n");
> >
> > static PyObject *
> >  py_acquire(PyObject *self __unused, PyObject *args, PyObject *keywds)
> >  {
> > int rv, sanlockfd = -1, pid = -1, shared = 0;
> > const char *lockspace, *resource;
> > struct sanlk_resource *res;
> >
> > int rv = -1, sanlockfd = -1, pid = -1, shared = 0;
> >
> > PyObject *lockspace = NULL, *resource = NULL;
> >
> > struct sanlk_resource *res = NULL;
> > PyObject *disks, *version = Py_None;
> >
> > static char *kwlist[] = {"lockspace", "resource", "disks", "slkfd",
> >                             "pid", "shared", "version", NULL};
> >
> > /* parse python tuple */
> > if (!PyArg_ParseTupleAndKeywords(args, keywds, "ssO!|iiiO", kwlist,
> >    &lockspace, &resource, &PyList_Type, &disks, &sanlockfd, &pid,
> >    &shared, &version)) {
> >    return NULL;
> >
> > if (!PyArg_ParseTupleAndKeywords(args, keywds, "O&O&O!|iiiO", kwlist,
> >    convert_to_pybytes, &lockspace, convert_to_pybytes, &resource,
> >    &PyList_Type, &disks, &sanlockfd, &pid, &shared, &version)) {
> >    goto finally;
> >
> > }
> >
> > /* check if any of the slkfd or pid parameters was given */
> >    if (sanlockfd == -1 && pid == -1) {
> >        __set_exception(EINVAL, "Invalid slkfd and pid values");
> >    return NULL;
> >    goto finally;
> >
> > }
> >
> > /* parse and check sanlock resource */
> >    if (__parse_resource(disks, &res) < 0) {
> >    return NULL;
> >    goto finally;
> >
> > }
> >
> > /* prepare sanlock names */
> > strncpy(res->lockspace_name, lockspace, SANLK_NAME_LEN);
> > strncpy(res->name, resource, SANLK_NAME_LEN);
> > strncpy(res->lockspace_name, PyBytes_AsString(lockspace),
> >
> > SANLK_NAME_LEN);
> >
> > strncpy(res->name, PyBytes_AsString(resource), SANLK_NAME_LEN);
> >
> > /* prepare sanlock flags */
> > if (shared) {
> >     res->flags |= SANLK_RES_SHARED;
> > }
> >
> > @@ -1069,30 +1069,31 @@ py_acquire(PyObject *self __unused, PyObject
> > *args, PyObject *keywds)
> >      if (version != Py_None) {
> >          res->flags |= SANLK_RES_LVER;
> >          res->lver = pyinteger_as_unsigned_long_long_mask(version);
> >          if (res->lver == (uint64_t)-1) {
> >              __set_exception(EINVAL, "Unable to convert the version
> > value");
> >        goto exit_fail;
> >        goto finally;
> >    }
> >
> > }
> >
> > /* acquire sanlock resource (gil disabled) */
> >    Py_BEGIN_ALLOW_THREADS
> >    rv = sanlock_acquire(sanlockfd, pid, 0, 1, &res, 0);
> >    Py_END_ALLOW_THREADS
> >
> > if (rv != 0) {
> >        __set_exception(rv, "Sanlock resource not acquired");
> >    goto exit_fail;
> >    goto finally;
> > }
> >
> > +finally:
> > Py_XDECREF(lockspace);
> > Py_XDECREF(resource);
> > free(res);
> > if (rv != 0)
>
> Is it intentional "rv != 0" instead of "rv < 0"? I do see "rv != 0" in the
> existing code a few lines above in the method, but wasn't it a mistake? If
> the convention is that any non-negative is a success, then it should be
> changed.
> >    return NULL;
> > Py_RETURN_NONE;
> >
> > -exit_fail:
> > free(res);
> > return NULL;
> >
> > }
> >
> > /* release */
> >  PyDoc_STRVAR(pydoc_release, "\
> >  release(lockspace, resource, disks [, slkfd=fd, pid=owner])\n\
> > --
> > 2.17.2