Correct cause of NPE in python wrapper

[ric-plt/lib/rmr.git] / src / bindings / rmr-python / rmr / rmr.py

diff --git a/src/bindings/rmr-python/rmr/rmr.py b/src/bindings/rmr-python/rmr/rmr.py
index 9d21b88..9e45dd6 100644 (file)
--- a/src/bindings/rmr-python/rmr/rmr.py
+++ b/src/bindings/rmr-python/rmr/rmr.py
@@ -69,7 +69,7 @@ def _get_mapping_dict(cache={}):
     RMR_ERR_TIMEOUT     12  message processing call timed out
     RMR_ERR_UNSET       13  the message hasn't been populated with a transport buffer
     RMR_ERR_TRUNC       14  received message likely truncated
-    RMR_ERR_INITFAILED  15  initialisation of something (probably message) failed
+    RMR_ERR_INITFAILED  15  initialization of something (probably message) failed
 
     """
     if cache:
@@ -93,6 +93,9 @@ def _state_to_status(stateno):
     return sdict.get(stateno, "UNKNOWN STATE")
 
 
+_RCONST = _get_constants()
+
+
 ##############
 # PUBLIC API
 ##############
@@ -100,7 +103,13 @@ def _state_to_status(stateno):
 
 # These constants are directly usable by importers of this library
 # TODO: Are there others that will be useful?
-RMR_MAX_RCV_BYTES = _get_constants()["RMR_MAX_RCV_BYTES"]
+
+RMR_MAX_RCV_BYTES = _RCONST["RMR_MAX_RCV_BYTES"]
+RMRFL_MTCALL = _RCONST.get("RMRFL_MTCALL", 0x02)  # initialization flags
+RMRFL_NONE = _RCONST.get("RMRFL_NONE", 0x0)
+RMR_OK = _RCONST["RMR_OK"]  # useful state constants
+RMR_ERR_TIMEOUT = _RCONST["RMR_ERR_TIMEOUT"]
+RMR_ERR_RETRY = _RCONST["RMR_ERR_RETRY"]
 
 
 class rmr_mbuf_t(Structure):
@@ -213,6 +222,20 @@ def rmr_alloc_msg(vctx, size):
     return _rmr_alloc_msg(vctx, size)
 
 
+_rmr_free_msg = rmr_c_lib.rmr_free_msg
+_rmr_free_msg.argtypes = [c_void_p]
+_rmr_free_msg.restype = None
+
+
+def rmr_free_msg(mbuf):
+    """
+    Refer to the rmr C documentation for rmr_free_msg
+    extern void rmr_free_msg( rmr_mbuf_t* mbuf )
+    """
+    if mbuf is not None:
+        _rmr_free_msg(mbuf)
+
+
 _rmr_payload_size = rmr_c_lib.rmr_payload_size
 _rmr_payload_size.argtypes = [POINTER(rmr_mbuf_t)]
 _rmr_payload_size.restype = c_int
@@ -309,22 +332,39 @@ def rmr_bytes2meid(ptr_mbuf, src, length):
     return _rmr_bytes2meid(ptr_mbuf, src, length)
 
 
+# this is an alias to rmr_bytes2meid using familiar set/get terminoloigy
+rmr_set_meid = rmr_bytes2meid
+
 # CAUTION:  Some of the C functions expect a mutable buffer to copy the bytes into;
 #           if there is a get_* function below, use it to set up and return the
 #           buffer properly.
 
-
+# extern unsigned char*  rmr_get_meid(rmr_mbuf_t* mbuf, unsigned char* dest);
+# we don't provide direct access to this function (unless it is asked for) because it is not really useful to provide your own buffer.
+# Rather, rmr_get_meid does this for you, and just returns the string.
 _rmr_get_meid = rmr_c_lib.rmr_get_meid
 _rmr_get_meid.argtypes = [POINTER(rmr_mbuf_t), c_char_p]
 _rmr_get_meid.restype = c_char_p
 
 
-def rmr_get_meid(ptr_mbuf, dest):
+def rmr_get_meid(ptr_mbuf):
     """
-    Refer to the rmr C documentation for rmr_get_meid
-    extern unsigned char*  rmr_get_meid(rmr_mbuf_t* mbuf, unsigned char* dest);
+    Get the managed equipment ID (meid) from the message header.
+
+    Parameters
+    ----------
+    ptr_mbuf: ctypes c_void_p
+        Pointer to an rmr message buffer
+
+    Returns
+    -------
+    string:
+        meid
     """
-    return _rmr_get_meid(ptr_mbuf, dest)
+    sz = _get_constants().get("RMR_MAX_MEID", 64)  # size for buffer to fill
+    buf = create_string_buffer(sz)
+    _rmr_get_meid(ptr_mbuf, buf)
+    return buf.value.decode()  # decode turns into a string
 
 
 _rmr_get_src = rmr_c_lib.rmr_get_src
@@ -397,15 +437,8 @@ def message_summary(ptr_mbuf):
     dict:
         dict message summary
     """
-    if ptr_mbuf.contents.len > RMR_MAX_RCV_BYTES:
-        return "Malformed message: message length is greater than the maximum possible"
-
-    meid = get_meid(ptr_mbuf)
-    if meid == "\000" * _get_constants().get("RMR_MAX_MEID", 32):  # special case all nils
-        meid = None
-
     return {
-        "payload": get_payload(ptr_mbuf),
+        "payload": get_payload(ptr_mbuf) if ptr_mbuf.contents.state == RMR_OK else None,
         "payload length": ptr_mbuf.contents.len,
         "message type": ptr_mbuf.contents.mtype,
         "subscription id": ptr_mbuf.contents.sub_id,
@@ -413,7 +446,7 @@ def message_summary(ptr_mbuf):
         "message state": ptr_mbuf.contents.state,
         "message status": _state_to_status(ptr_mbuf.contents.state),
         "payload max size": rmr_payload_size(ptr_mbuf),
-        "meid": meid,
+        "meid": rmr_get_meid(ptr_mbuf),
         "message source": get_src(ptr_mbuf),
         "errno": ptr_mbuf.contents.tp_state,
     }
@@ -450,27 +483,6 @@ def generate_and_set_transaction_id(ptr_mbuf):
     memmove(ptr_mbuf.contents.xaction, uu_id, sz)
 
 
-def get_meid(ptr_mbuf):
-    """
-    | Get the managed equipment ID (meid) from the message header.
-    | This is a 32 byte field and RMr returns all 32 bytes which if the sender did not set will be garbage.
-
-    Parameters
-    ----------
-    ptr_mbuf: ctypes c_void_p
-        Pointer to an rmr message buffer
-
-    Returns
-    -------
-    string:
-        meid
-    """
-    sz = _get_constants().get("RMR_MAX_MEID", 64)  # size for buffer to fill
-    buf = create_string_buffer(sz)
-    rmr_get_meid(ptr_mbuf, buf)
-    return buf.raw.decode()
-
-
 def get_src(ptr_mbuf):
     """
     Get the message source (likely host:port)
@@ -483,7 +495,7 @@ def get_src(ptr_mbuf):
     Returns
     -------
     string:
-        meid
+        message source
     """
     sz = _get_constants().get("RMR_MAX_SRC", 64)  # size to fill
     buf = create_string_buffer(sz)