Re: [Xen-devel] [PATCH 3/3] python: Add binding for non-blocking xs_check_watch()

[Wei Liu]

On Fri, Sep 15, 2017 at 05:35:36PM +0100, Euan Harris wrote:
> xs_check_watch() checks for watch notifications without blocking.
> Together with the binding for xs_fileno(), this makes it possible
> to write event-driven clients in Python.
> 
> Signed-off-by: Euan Harris 

Reviewed-by: Wei Liu 

___
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel

[Xen-devel] [PATCH 3/3] python: Add binding for non-blocking xs_check_watch()

[Euan Harris]

xs_check_watch() checks for watch notifications without blocking.
Together with the binding for xs_fileno(), this makes it possible
to write event-driven clients in Python.

Signed-off-by: Euan Harris 
---
 tools/python/xen/lowlevel/xs/xs.c | 28 
 1 file changed, 28 insertions(+)

diff --git a/tools/python/xen/lowlevel/xs/xs.c 
b/tools/python/xen/lowlevel/xs/xs.c
index a4b50a0..c9a9259 100644
--- a/tools/python/xen/lowlevel/xs/xs.c
+++ b/tools/python/xen/lowlevel/xs/xs.c
@@ -474,6 +474,33 @@ static PyObject *xspy_fileno(XsHandle *self)
 }
 
 
+#define xspy_check_watch_doc "\n"  \
+   "Check for watch notifications without blocking.\n" \
+   "\n"\
+   "Returns: [tuple] (path, token).\n" \
+   " None if no watches have fired.\n" \
+   "Raises xen.lowlevel.xs.Error on error.\n"  \
+   "\n"
+
+static PyObject *xspy_check_watch(XsHandle *self, PyObject *args)
+{
+struct xs_handle *xh = xshandle(self);
+PyObject *val = NULL;
+char **xsval;
+
+if (!xh)
+return NULL;
+
+xsval = xs_check_watch(xh);
+if (!xsval) {
+return none(errno == EAGAIN);
+}
+
+val = match_watch_by_token(self, xsval);
+free(xsval);
+return val;
+}
+
 #define xspy_read_watch_doc "\n"   \
"Read a watch notification.\n"  \
"\n"\
@@ -912,6 +939,7 @@ static PyMethodDef xshandle_methods[] = {
 XSPY_METH(set_permissions,   METH_VARARGS),
 XSPY_METH(watch, METH_VARARGS),
 XSPY_METH(read_watch,METH_NOARGS),
+XSPY_METH(check_watch,   METH_NOARGS),
 XSPY_METH(unwatch,   METH_VARARGS),
 XSPY_METH(transaction_start, METH_NOARGS),
 XSPY_METH(transaction_end,   METH_VARARGS | METH_KEYWORDS),
-- 
1.8.3.1


___
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel