Python-API: Inital commit of Python bindings for the VPP API.
See: https://wiki.fd.io/view/VPP/Python_API

Change-Id: If135fc32208c7031787e1935b399d930e0e1ea1f
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/vpp-api/python/vpp_papi/pneum_wrap.c b/vpp-api/python/vpp_papi/pneum_wrap.c
new file mode 100644
index 0000000..09d972d
--- /dev/null
+++ b/vpp-api/python/vpp_papi/pneum_wrap.c
@@ -0,0 +1,120 @@
+#include <Python.h>
+#include "pneum.h"
+
+static PyObject *pneum_callback = NULL;
+
+int
+wrap_pneum_callback (char *data, int len)
+{
+  PyGILState_STATE gstate;
+  PyObject *result;//, *arglist;
+
+  gstate = PyGILState_Ensure();
+
+  /* Time to call the callback */
+  result = PyObject_CallFunction(pneum_callback, "y#", data, len);
+  if (result)
+    Py_DECREF(result);
+  else
+    PyErr_Print();
+
+  PyGILState_Release(gstate);
+  return (0);
+}
+
+static PyObject *
+wrap_connect (PyObject *self, PyObject *args)
+{
+  char *name;
+  int rv;
+  PyObject *temp;
+
+  if (!PyArg_ParseTuple(args, "sO:set_callback", &name, &temp))
+    return (NULL);
+  
+  if (!PyCallable_Check(temp)) {
+    PyErr_SetString(PyExc_TypeError, "parameter must be callable");
+    return NULL;
+  }
+
+  Py_XINCREF(temp);         /* Add a reference to new callback */
+  Py_XDECREF(pneum_callback);  /* Dispose of previous callback */
+  pneum_callback = temp;       /* Remember new callback */
+
+  Py_BEGIN_ALLOW_THREADS
+  rv = pneum_connect(name);
+  Py_END_ALLOW_THREADS
+  return PyLong_FromLong(rv);
+}
+
+static PyObject *
+wrap_disconnect (PyObject *self, PyObject *args)
+{
+  int rv;
+  Py_BEGIN_ALLOW_THREADS
+  rv = pneum_disconnect();
+  Py_END_ALLOW_THREADS
+  return PyLong_FromLong(rv);
+}
+static PyObject *
+wrap_write (PyObject *self, PyObject *args)
+{
+  char *data;
+  int len, rv;
+
+  if (!PyArg_ParseTuple(args, "s#", &data, &len)) 
+    return NULL;     
+  Py_BEGIN_ALLOW_THREADS
+  rv = pneum_write(data, len);
+  Py_END_ALLOW_THREADS
+
+  return PyLong_FromLong(rv);
+}
+
+void vl_msg_api_free(void *);
+
+static PyObject *
+wrap_read (PyObject *self, PyObject *args)
+{
+  char *data;
+  int len, rv;
+
+  Py_BEGIN_ALLOW_THREADS
+  rv = pneum_read(&data, &len);
+  Py_END_ALLOW_THREADS
+
+  if (rv != 0) { Py_RETURN_NONE; }
+
+  PyObject *ret = Py_BuildValue("y#", data, len);
+  if (!ret) { Py_RETURN_NONE; }
+
+  vl_msg_api_free(data);
+  return ret;
+}
+
+static PyMethodDef vpp_api_Methods[] = {
+  {"connect", wrap_connect, METH_VARARGS, "Connect to the VPP API."},
+  {"disconnect", wrap_disconnect, METH_VARARGS, "Disconnect from the VPP API."},
+  {"write", wrap_write, METH_VARARGS, "Write data to the VPP API."},
+  {"read", wrap_read, METH_VARARGS, "Read data from the VPP API."},
+  {NULL, NULL, 0, NULL}        /* Sentinel */
+};
+
+static struct PyModuleDef vpp_api_module = {
+  PyModuleDef_HEAD_INIT,
+  "vpp_api",   /* name of module */
+   NULL, /* module documentation, may be NULL */
+  -1,       /* size of per-interpreter state of the module,
+	       or -1 if the module keeps state in global variables. */
+  vpp_api_Methods
+};
+
+PyMODINIT_FUNC
+PyInit_vpp_api (void)
+{
+  /* Ensure threading is initialised */
+  if (!PyEval_ThreadsInitialized()) {
+    PyEval_InitThreads();
+  }
+  return PyModule_Create(&vpp_api_module);
+}