pgpool2.git / summary / log / commit / refs
commit fdee24870b548c7091561cdff15ea41547eeb942
Author: Tatsuo Ishii <ishii@postgresql.org>
Date: Tue Oct 02 00:28:01 2012 +0000
Fix long standing problem with do_query(). When 1) extended protocol
used and 2)unnamed portal is used and 3) no explicit transaction is
used, user's unnamed portal is removed by Sync message. This is
because Sync message closes transaction and unnamed portal is
removed. This leads to "portal "" does not exist" error.
Fix is, use "Flush" message instead of Sync. Main difference between
using Sync and Flush is, Flush does not return Ready for Query
message. So do_query() does not return until all expected responses
are returned. It seems the order of messages returned from backend is
random, and do_query() manages it by using state bits.
pool_process_query.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 52 insertions(+), 5 deletions(-)
diff --git a/pool_process_query.c b/pool_process_query.c
index 8f7fd0d34..f08e2200d 100644
--- a/pool_process_query.c
+++ b/pool_process_query.c
@@ -2301,6 +2301,23 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
{
#define DO_QUERY_ALLOC_NUM 1024 /* memory allocation unit for POOL_SELECT_RESULT */
+/*
+ * State transition control bits. We expect all following events have
+ * been occur before finish do_query() in extended protocol mode.
+ * Note that "Close Compplete" should occur twice, because two close
+ * requests(one for prepared statement and the other for portal) have
+ * been sent.
+ */
+#define PARSE_COMPLETE_RECEIVED (1 << 0)
+#define BIND_COMPLETE_RECEIVED (1 << 1)
+#define CLOSE_COMPLETE_RECEIVED (1 << 2)
+#define COMMAND_COMPLETE_RECEIVED (1 << 3)
+#define ROW_DESCRIPTION_RECEIVED (1 << 4)
+#define DATA_ROW_RECEIVED (1 << 5)
+#define STATE_COMPLETED (PARSE_COMPLETE_RECEIVED | BIND_COMPLETE_RECEIVED |\
+ CLOSE_COMPLETE_RECEIVED | COMMAND_COMPLETE_RECEIVED | \
+ ROW_DESCRIPTION_RECEIVED | DATA_ROW_RECEIVED)
+
int i;
int len;
char kind;
@@ -2318,8 +2335,12 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
int nbytes;
static char nullmap[8192];
unsigned char mask = 0;
+ bool doing_extended;
+ int num_close_complete;
+ int state;
- pool_debug("do_query: extended:%d query:%s", pool_get_session_context() && pool_is_doing_extended_query_message(), query);
+ doing_extended = pool_get_session_context() && pool_is_doing_extended_query_message();
+ pool_debug("do_query: extended:%d query:%s", doing_extended, query);
*result = NULL;
res = malloc(sizeof(*res));
@@ -2450,9 +2471,9 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
pool_write(backend, prepared_name, pname_len);
/*
- * Send sync message
+ * Send flush message
*/
- pool_write(backend, "S", 1);
+ pool_write(backend, "H", 1);
len = htonl(sizeof(len));
pool_write_and_flush(backend, &len, sizeof(len));
}
@@ -2472,6 +2493,10 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
* our internal use of SQL command (otherwise users will be
* confused).
*/
+
+ num_close_complete = 0;
+ state = 0;
+
for(;;)
{
if (pool_read(backend, &kind, sizeof(kind)) < 0)
@@ -2514,6 +2539,7 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
else
{
mask = 0;
+
if (kind == 'C' || kind == 'E' || kind == 'N' || kind == 'P')
{
if (pool_read_string(backend, &len, 0) == NULL)
@@ -2528,23 +2554,36 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
{
case 'Z': /* Ready for query */
pool_debug("do_query: Ready for query");
- return POOL_CONTINUE;
+ if (!doing_extended)
+ return POOL_CONTINUE;
break;
case 'C': /* Command Complete */
pool_debug("do_query: Command complete received");
+ state |= COMMAND_COMPLETE_RECEIVED;
break;
case '1': /* Parse complete */
+ pool_debug("do_query: Parse complete received");
+ state |= PARSE_COMPLETE_RECEIVED;
+ break;
+
case '2': /* Bind complete */
- pool_debug("do_query: %c complete received", kind);
+ pool_debug("do_query: Bind complete received");
+ state |= BIND_COMPLETE_RECEIVED;
break;
case '3': /* Close complete */
pool_debug("do_query: Close complete received");
+ num_close_complete++;
+ if (num_close_complete >= 2)
+ state |= CLOSE_COMPLETE_RECEIVED;
break;
case 'T': /* Row Description */
+ state |= ROW_DESCRIPTION_RECEIVED;
+ pool_debug("do_query: row description received");
+
if (major == PROTO_MAJOR_V3)
{
p = packet;
@@ -2640,6 +2679,9 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
break;
case 'D': /* data row */
+ state |= DATA_ROW_RECEIVED;
+ pool_debug("do_query: data row received");
+
if (major == PROTO_MAJOR_V3)
{
p = packet;
@@ -2760,6 +2802,11 @@ POOL_STATUS do_query(POOL_CONNECTION *backend, char *query, POOL_SELECT_RESULT *
break;
}
+ if (doing_extended && (state & STATE_COMPLETED) == STATE_COMPLETED)
+ {
+ pool_debug("do_qyery: all state completed");
+ break;
+ }
}
return POOL_CONTINUE;
}
[parent: 36c9d4cfe913]