database/postgres
database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-05-02 11:44:50 +03:00
Code

libpq: Fix another bug in 721f7bd3cbccaf8c07cad2707826b83f84694832.

Browse Source 
If we failed to connect to one or more hosts, and then afterwards we
find one that fails to be read-write, the latter error message was
clobbering any earlier ones.  Repair.

Mithun Cy, slightly revised by me.
This commit is contained in:
Robert Haas 2016-12-05 14:09:54 -05:00
parent 2f4193c350
commit a0ae54df9b
1 changed files with 66 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
src/interfaces/libpq/fe-connect.c
View File

@ -1762,6 +1762,39 @@ connectDBComplete(PGconn *conn)
}
}
/*
* This subroutine saves conn->errorMessage, which will be restored back by
* restoreErrorMessage subroutine.
*/
static bool
saveErrorMessage(PGconn *conn, PQExpBuffer savedMessage)
{
initPQExpBuffer(savedMessage);
if (PQExpBufferBroken(savedMessage))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
appendPQExpBufferStr(savedMessage,
conn->errorMessage.data);
resetPQExpBuffer(&conn->errorMessage);
return true;
}
/*
* Restores saved error messages back to conn->errorMessage.
*/
static void
restoreErrorMessage(PGconn *conn, PQExpBuffer savedMessage)
{
appendPQExpBufferStr(savedMessage, conn->errorMessage.data);
resetPQExpBuffer(&conn->errorMessage);
appendPQExpBufferStr(&conn->errorMessage, savedMessage->data);
termPQExpBuffer(savedMessage);
}
/* ----------------
* PQconnectPoll
*
@ -1795,6 +1828,7 @@ PQconnectPoll(PGconn *conn)
PGresult *res;
char sebuf[256];
int optval;
PQExpBufferData savedMessage;
if (conn == NULL)
return PGRES_POLLING_FAILED;
@ -2792,11 +2826,26 @@ keep_going: /* We will come back to here until there is
if (conn->target_session_attrs != NULL &&
strcmp(conn->target_session_attrs, "read-write") == 0)
{
/*
* We are yet to make a connection. Save all existing error
* messages until we make a successful connection state.
* This is important because PQsendQuery is going to reset
* conn->errorMessage and we will loose error messages
* related to previous hosts we have tried to connect and
* failed.
*/
if (!saveErrorMessage(conn, &savedMessage))
goto error_return;
conn->status = CONNECTION_OK;
if (!PQsendQuery(conn,
"show transaction_read_only"))
{
restoreErrorMessage(conn, &savedMessage);
goto error_return;
}
conn->status = CONNECTION_CHECK_WRITABLE;
restoreErrorMessage(conn, &savedMessage);
return PGRES_POLLING_READING;
}
@ -2841,11 +2890,18 @@ keep_going: /* We will come back to here until there is
if (conn->target_session_attrs != NULL &&
strcmp(conn->target_session_attrs, "read-write") == 0)
{
if (!saveErrorMessage(conn, &savedMessage))
goto error_return;
conn->status = CONNECTION_OK;
if (!PQsendQuery(conn,
"show transaction_read_only"))
{
restoreErrorMessage(conn, &savedMessage);
goto error_return;
}
conn->status = CONNECTION_CHECK_WRITABLE;
restoreErrorMessage(conn, &savedMessage);
return PGRES_POLLING_READING;
}
@ -2858,13 +2914,20 @@ keep_going: /* We will come back to here until there is
case CONNECTION_CHECK_WRITABLE:
{
if (!saveErrorMessage(conn, &savedMessage))
goto error_return;
conn->status = CONNECTION_OK;
if (!PQconsumeInput(conn))
{
restoreErrorMessage(conn, &savedMessage);
goto error_return;
}
if (PQisBusy(conn))
{
conn->status = CONNECTION_CHECK_WRITABLE;
restoreErrorMessage(conn, &savedMessage);
return PGRES_POLLING_READING;
}
@ -2878,6 +2941,7 @@ keep_going: /* We will come back to here until there is
if (strncmp(val, "on", 2) == 0)
{
PQclear(res);
restoreErrorMessage(conn, &savedMessage);
/* Not writable; close connection. */
appendPQExpBuffer(&conn->errorMessage,
@ -2902,6 +2966,7 @@ keep_going: /* We will come back to here until there is
goto error_return;
}
PQclear(res);
termPQExpBuffer(&savedMessage);
/* We can release the address lists now. */
release_all_addrinfo(conn);
@ -2917,6 +2982,7 @@ keep_going: /* We will come back to here until there is
*/
if (res)
PQclear(res);
restoreErrorMessage(conn, &savedMessage);
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("test \"show transaction_read_only\" failed "
" on \"%s:%s\" \n"),