NOTIFYs fix and poll status changes

POLL_OK has been changed from 3 to 0 to let the user specify a short loop
just as "if not curs.poll()" instead of having to check for write and read
separately. For an example of this, see examples/notify.py.

4 files changed, 16 insertions, 15 deletions

diff --git a/psycopg/connection.h b/psycopg/connection.h
index c0fec18..ec8e869 100644
--- a/psycopg/connection.h
+++ b/psycopg/connection.h
@@ -53,11 +53,10 @@ extern "C" {
 #define ASYNC_READ  1
 #define ASYNC_WRITE 2
 
-/* polling result, try to keep in sync with PostgresPollingStatusType from
-   libpq-fe.h */
+/* polling result */
+#define PSYCO_POLL_OK    0
 #define PSYCO_POLL_READ  1
 #define PSYCO_POLL_WRITE 2
-#define PSYCO_POLL_OK    3
 
 /* Hard limit on the notices stored by the Python connection */
 #define CONN_NOTICES_LIMIT 50
diff --git a/psycopg/cursor.h b/psycopg/cursor.h
index bbe80ea..a0a3a82 100644
--- a/psycopg/cursor.h
+++ b/psycopg/cursor.h
@@ -62,10 +62,10 @@ typedef struct {
     PyObject   *pgstatus;  /* last message from the server after an execute */
     Oid         lastoid;   /* last oid from an insert or InvalidOid */
 
-    PyObject *casts;      /* an array (tuple) of typecast functions */
-    PyObject *caster;     /* the current typecaster object */
+    PyObject *casts;       /* an array (tuple) of typecast functions */
+    PyObject *caster;      /* the current typecaster object */
 
-    PyObject *copyfile;   /* file-like used during COPY TO/FROM ops */
+    PyObject  *copyfile;   /* file-like used during COPY TO/FROM ops */
     Py_ssize_t copysize;   /* size of the copy buffer during COPY TO/FROM ops */
 #define DEFAULT_COPYSIZE 16384
 #define DEFAULT_COPYBUFF  8132
diff --git a/psycopg/cursor_int.c b/psycopg/cursor_int.c
index 4a63f0c..1147284 100644
--- a/psycopg/cursor_int.c
+++ b/psycopg/cursor_int.c
@@ -141,9 +141,16 @@ curs_poll_fetch(cursorObject *self)
         return PyInt_FromLong(PSYCO_POLL_READ);
     }
 
-    /* data has arrived, try to fetch all of it or, if it failed, tell the
-       user to wait more */
-    last_result = curs_get_last_result(self);
+    /* try to fetch the data only if this was a poll following a read
+       request; else just return POLL_OK to the user: this is necessary
+       because of asynchronous NOTIFYs that can be sent by the backend
+       even if the user didn't asked for them */
+
+    if (self->conn->async_status == ASYNC_READ)
+        last_result = curs_get_last_result(self);
+    else
+        last_result = 0;
+
     if (last_result == 0) {
         Dprintf("cur_poll_fetch: returning %d", PSYCO_POLL_OK);
         return PyInt_FromLong(PSYCO_POLL_OK);
diff --git a/psycopg/cursor_type.c b/psycopg/cursor_type.c
index 73217c2..895b3ce 100644
--- a/psycopg/cursor_type.c
+++ b/psycopg/cursor_type.c
@@ -1485,14 +1485,9 @@ psyco_curs_poll(cursorObject *self)
     if (self->conn->async_status == ASYNC_WRITE) {
         return curs_poll_send(self);
     }
-    else if (self->conn->async_status == ASYNC_READ) {
+    else  {
         return curs_poll_fetch(self);
     }
-    else {
-        PyErr_Format(OperationalError, "unexpected execution status: %d",
-                     self->conn->async_status);
-        return NULL;
-    }
 }
 
 /* extension: closed - return true if cursor is closed*/