/*
* closeGTM_Conn
* - properly close a connection to the backend
*
* This should reset or release all transient state, but NOT the connection
* parameters. On exit, the GTM_Conn should be in condition to start a fresh
* connection with the same parameters (see PQreset()).
*/
static void
closeGTM_Conn(GTM_Conn *conn)
{
/*
* Note that the protocol doesn't allow us to send Terminate messages
* during the startup phase.
*/
if (conn->sock >= 0 && conn->status == CONNECTION_OK)
{
/*
* Try to send "close connection" message to backend. Ignore any
* error.
*
* Force length word for backends may try to read that in a generic
* code
*/
gtmpqPutMsgStart('X', true, conn);
gtmpqPutMsgEnd(conn);
gtmpqFlush(conn);
}
/*
* Close the connection, reset all transient state, flush I/O buffers.
*/
if (conn->sock >= 0)
close(conn->sock);
conn->sock = -1;
conn->status = CONNECTION_BAD; /* Well, not really _bad_ - just
* absent */
gtm_freeaddrinfo_all(conn->addrlist_family, conn->addrlist);
conn->addrlist = NULL;
conn->addr_cur = NULL;
conn->inStart = conn->inCursor = conn->inEnd = 0;
conn->outCount = 0;
}
GTM_Result *
GTMPQgetResult(GTM_Conn *conn)
{
GTM_Result *res;
if (!conn)
return NULL;
/* Parse any available data, if our state permits. */
while ((res = pqParseInput(conn)) == NULL)
{
int flushResult;
/*
* If data remains unsent, send it. Else we might be waiting for the
* result of a command the backend hasn't even got yet.
*/
while ((flushResult = gtmpqFlush(conn)) > 0)
{
if (gtmpqWait(false, true, conn))
{
flushResult = -1;
break;
}
}
/* Wait for some more data, and load it. */
if (flushResult ||
gtmpqWait(true, false, conn) ||
gtmpqReadData(conn) < 0)
{
/*
* conn->errorMessage has been set by gtmpqWait or gtmpqReadData.
*/
return NULL;
}
}
return res;
}
/*
* pqPacketSend() -- convenience routine to send a message to server.
*
* pack_type: the single-byte message type code. (Pass zero for startup
* packets, which have no message type code.)
*
* buf, buf_len: contents of message. The given length includes only what
* is in buf; the message type and message length fields are added here.
*
* RETURNS: STATUS_ERROR if the write fails, STATUS_OK otherwise.
* SIDE_EFFECTS: may block.
*
* Note: all messages sent with this routine have a length word, whether
* it's protocol 2.0 or 3.0.
*/
static int
pqPacketSend(GTM_Conn *conn, char pack_type,
const void *buf, size_t buf_len)
{
/* Start the message. */
if (gtmpqPutMsgStart(pack_type, true, conn))
return STATUS_ERROR;
/* Send the message body. */
if (gtmpqPutnchar(buf, buf_len, conn))
return STATUS_ERROR;
/* Finish the message. */
if (gtmpqPutMsgEnd(conn))
return STATUS_ERROR;
/* Flush to ensure backend gets it. */
if (gtmpqFlush(conn))
return STATUS_ERROR;
return STATUS_OK;
}