/*
* Special for sending SET commands that change GUC variables, so they go to all
* gangs, both reader and writer
*/
void
CdbSetGucOnAllGangs(const char *strCommand,
bool cancelOnError, bool needTwoPhase)
{
volatile CdbDispatcherState ds = { NULL, NULL };
const bool withSnapshot = true;
elog((Debug_print_full_dtm ? LOG : DEBUG5),
"CdbSetGucOnAllGangs for command = '%s', needTwoPhase = %s",
strCommand, (needTwoPhase ? "true" : "false"));
dtmPreCommand("CdbSetGucOnAllGangs", strCommand, NULL, needTwoPhase,
withSnapshot, false /* inCursor */ );
PG_TRY();
{
cdbdisp_dispatchSetCommandToAllGangs(strCommand, NULL, 0, NULL, 0,
cancelOnError, needTwoPhase,
(struct CdbDispatcherState *)
&ds);
/*
* Wait for all QEs to finish. If not all of our QEs were successful,
* report the error and throw up.
*/
cdbdisp_finishCommand((struct CdbDispatcherState *) &ds, NULL, NULL);
}
PG_CATCH();
{
/*
* Something happend, clean up after ourselves
*/
CdbCheckDispatchResult((struct CdbDispatcherState *) &ds,
DISPATCH_WAIT_CANCEL);
cdbdisp_destroyDispatcherState((struct CdbDispatcherState *) &ds);
PG_RE_THROW();
}
PG_END_TRY();
}
/*
* cdbdisp_handleError
*
* When caller catches an error, the PG_CATCH handler can use this
* function instead of cdbdisp_finishCommand to wait for all QEs
* to finish, clean up, and report QE errors if appropriate.
* This function should be called only from PG_CATCH handlers.
*
* This function destroys and frees the given CdbDispatchResults objects.
* It is a no-op if both CdbDispatchResults ptrs are NULL.
*
* On return, the caller is expected to finish its own cleanup and
* exit via PG_RE_THROW().
*/
void
cdbdisp_handleError(struct CdbDispatcherState *ds)
{
int qderrcode;
bool useQeError = false;
qderrcode = elog_geterrcode();
/*
* If cdbdisp_dispatchToGang() wasn't called, don't wait.
*/
if (!ds || !ds->primaryResults)
return;
/*
* Request any remaining commands executing on qExecs to stop.
* We need to wait for the threads to finish. This allows for proper
* cleanup of the results from the async command executions.
* Cancel any QEs still running.
*/
CdbCheckDispatchResult(ds, DISPATCH_WAIT_CANCEL);
/*
* When a QE stops executing a command due to an error, as a
* consequence there can be a cascade of interconnect errors
* (usually "sender closed connection prematurely") thrown in
* downstream processes (QEs and QD). So if we are handling
* an interconnect error, and a QE hit a more interesting error,
* we'll let the QE's error report take precedence.
*/
if (qderrcode == ERRCODE_GP_INTERCONNECTION_ERROR)
{
bool qd_lost_flag = false;
char *qderrtext = elog_message();
if (qderrtext
&& strcmp(qderrtext, CDB_MOTION_LOST_CONTACT_STRING) == 0)
qd_lost_flag = true;
if (ds->primaryResults && ds->primaryResults->errcode)
{
if (qd_lost_flag
&& ds->primaryResults->errcode == ERRCODE_GP_INTERCONNECTION_ERROR)
useQeError = true;
else if (ds->primaryResults->errcode != ERRCODE_GP_INTERCONNECTION_ERROR)
useQeError = true;
}
}
if (useQeError)
{
/*
* Throw the QE's error, catch it, and fall thru to return
* normally so caller can finish cleaning up. Afterwards
* caller must exit via PG_RE_THROW().
*/
PG_TRY();
{
cdbdisp_finishCommand(ds, NULL, NULL);
}
PG_CATCH();
{
} /* nop; fall thru */
PG_END_TRY();
}
else
{
/*
* Discard any remaining results from QEs; don't confuse matters by
* throwing a new error. Any results of interest presumably should
* have been examined before raising the error that the caller is
* currently handling.
*/
cdbdisp_destroyDispatcherState(ds);
}
}
/*
* Wait for all QEs to finish, then report any errors from the given
* CdbDispatchResults objects and free them. If not all QEs in the
* associated gang(s) executed the command successfully, throws an
* error and does not return. No-op if both CdbDispatchResults ptrs are NULL.
* This is a convenience function; callers with unusual requirements may
* instead call CdbCheckDispatchResult(), etc., directly.
*/
void
cdbdisp_finishCommand(struct CdbDispatcherState *ds,
void (*handle_results_callback) (CdbDispatchResults *
primaryResults,
void *ctx), void *ctx)
{
StringInfoData buf;
int errorcode = 0;
/*
* If cdbdisp_dispatchToGang() wasn't called, don't wait.
*/
if (!ds || !ds->primaryResults)
return;
/*
* If we are called in the dying sequence, don't touch QE connections.
* Anything below could cause ERROR in which case we would miss a chance
* to clean up shared memory as this is from AbortTransaction.
* QE may stay a bit longer, but since we can consider QD as libpq
* client to QE, they will notice that we as a client do not
* appear anymore and will finish soon. Also ERROR report doesn't
* go to the client anyway since we are in proc_exit.
*/
if (proc_exit_inprogress)
return;
/*
* Wait for all QEs to finish. Don't cancel them.
*/
CdbCheckDispatchResult(ds, DISPATCH_WAIT_NONE);
/*
* If no errors, free the CdbDispatchResults objects and return.
*/
if (ds->primaryResults)
errorcode = ds->primaryResults->errcode;
if (!errorcode)
{
/*
* Call the callback function to handle the results
*/
if (handle_results_callback != NULL)
handle_results_callback(ds->primaryResults, ctx);
cdbdisp_destroyDispatcherState(ds);
return;
}
/*
* Format error messages from the primary gang.
*/
initStringInfo(&buf);
cdbdisp_dumpDispatchResults(ds->primaryResults, &buf);
cdbdisp_destroyDispatcherState(ds);
/*
* Too bad, our gang got an error.
*/
PG_TRY();
{
ereport(ERROR, (errcode(errorcode),
errOmitLocation(true), errmsg("%s", buf.data)));
}
PG_CATCH();
{
pfree(buf.data);
PG_RE_THROW();
}
PG_END_TRY();
}