From 85fdf7cb252264609d39c3440142e1bb31694fd3 Mon Sep 17 00:00:00 2001
From: Evgeniy Khramtsov <xramtsov@gmail.com>
Date: Mon, 29 Dec 2008 04:21:27 +0000
Subject: [PATCH] * src/odbc/ejabberd_odbc.erl: Print meaningful error message
when an SQL transaction exceeds number of restarts. Also rollbacks this
transaction to prevent deadlocks.
SVN Revision: 1761
---
ChangeLog | 6 ++++++
src/odbc/ejabberd_odbc.erl | 34 ++++++++++++++++++++++------------
2 files changed, 28 insertions(+), 12 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index baee8cf50..ed9ef0f4d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2008-12-29 Evgeniy Khramtsov <ekhramtsov@process-one.net>
+
+ * src/odbc/ejabberd_odbc.erl: Print meaningful error message when
+ an SQL transaction exceeds number of restarts. Also rollbacks
+ this transaction to prevent deadlocks.
+
2008-12-28 Mickael Remond <mremond@process-one.net>
* src/ejabberd_c2s.erl: We should allow use of bare resource in from by
diff --git a/src/odbc/ejabberd_odbc.erl b/src/odbc/ejabberd_odbc.erl
index c675c61c0..3a75b8a6e 100644
--- a/src/odbc/ejabberd_odbc.erl
+++ b/src/odbc/ejabberd_odbc.erl
@@ -55,6 +55,8 @@
-define(PGSQL_PORT, 5432).
-define(MYSQL_PORT, 3306).
+-define(TRANSACTION_TIMEOUT, 60000).
+-define(KEEPALIVE_TIMEOUT, 60000).
-define(KEEPALIVE_QUERY, "SELECT 1;").
%%%----------------------------------------------------------------------
@@ -68,7 +70,7 @@ start_link(Host, StartInterval) ->
sql_query(Host, Query) ->
gen_server:call(ejabberd_odbc_sup:get_random_pid(Host),
- {sql_query, Query}, 60000).
+ {sql_query, Query}, ?TRANSACTION_TIMEOUT).
%% SQL transaction based on a list of queries
%% This function automatically
@@ -83,7 +85,7 @@ sql_transaction(Host, Queries) when is_list(Queries) ->
%% SQL transaction, based on a erlang anonymous function (F = fun)
sql_transaction(Host, F) ->
gen_server:call(ejabberd_odbc_sup:get_random_pid(Host),
- {sql_transaction, F}, 60000).
+ {sql_transaction, F}, ?TRANSACTION_TIMEOUT).
%% This function is intended to be used from inside an sql_transaction:
sql_query_t(Query) ->
@@ -93,12 +95,12 @@ sql_query_t(Query) ->
{error, "No SQL-driver information available."} ->
% workaround for odbc bug
{updated, 0};
- {error, _} = Err ->
- exit(Err);
+ {error, Reason} ->
+ throw({aborted, Reason});
Rs when is_list(Rs) ->
case lists:keysearch(error, 1, Rs) of
- {value, Err} ->
- exit(Err);
+ {value, {error, Reason}} ->
+ throw({aborted, Reason});
_ ->
QRes
end;
@@ -177,7 +179,7 @@ handle_call({sql_query, Query}, _From, State) ->
{reply, Reply, State}
end;
handle_call({sql_transaction, F}, _From, State) ->
- case execute_transaction(State, F, ?MAX_TRANSACTION_RESTARTS) of
+ case execute_transaction(State, F, ?MAX_TRANSACTION_RESTARTS, "") of
% error returned by MySQL driver
{error, "query timed out"} ->
{stop, timeout, State};
@@ -247,14 +249,22 @@ sql_query_internal(State, Query) ->
mysql_to_odbc(mysql_conn:fetch(State#state.db_ref, Query, self()))
end.
-execute_transaction(_State, _F, 0) ->
+execute_transaction(State, _F, 0, Reason) ->
+ ?ERROR_MSG("SQL transaction restarts exceeded~n"
+ "** Restarts: ~p~n"
+ "** Last abort reason: ~p~n"
+ "** Stacktrace: ~p~n"
+ "** When State == ~p",
+ [?MAX_TRANSACTION_RESTARTS, Reason,
+ erlang:get_stacktrace(), State]),
+ sql_query_internal(State, "rollback;"),
{aborted, restarts_exceeded};
-execute_transaction(State, F, NRestarts) ->
+execute_transaction(State, F, NRestarts, _Reason) ->
put(?STATE_KEY, State),
sql_query_internal(State, "begin;"),
case catch F() of
- aborted ->
- execute_transaction(State, F, NRestarts - 1);
+ {aborted, Reason} ->
+ execute_transaction(State, F, NRestarts - 1, Reason);
{'EXIT', Reason} ->
sql_query_internal(State, "rollback;"),
{aborted, Reason};
@@ -360,7 +370,7 @@ mysql_item_to_odbc(Columns, Recs) ->
% perform a harmless query on all opened connexions to avoid connexion close.
keep_alive(PID) ->
- gen_server:call(PID, {sql_query, ?KEEPALIVE_QUERY}, 60000).
+ gen_server:call(PID, {sql_query, ?KEEPALIVE_QUERY}, ?KEEPALIVE_TIMEOUT).
% log function used by MySQL driver
log(Level, Format, Args) ->
--
2.40.0