ovsdb/trigger.c

   1 /* Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
   2  *
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 #include <config.h>
  17
  18 #include "trigger.h"
  19
  20 #include <limits.h>
  21
  22 #include "openvswitch/json.h"
  23 #include "jsonrpc.h"
  24 #include "ovsdb.h"
  25 #include "poll-loop.h"
  26 #include "server.h"
  27
  28 static bool ovsdb_trigger_try(struct ovsdb_trigger *, long long int now);
  29 static void ovsdb_trigger_complete(struct ovsdb_trigger *);
  30
  31 void
  32 ovsdb_trigger_init(struct ovsdb_session *session, struct ovsdb *db,
  33                    struct ovsdb_trigger *trigger,
  34                    struct json *request, long long int now,
  35                    bool read_only, const char *role,
  36                    const char *id)
  37 {
  38     trigger->session = session;
  39     trigger->db = db;
  40     ovs_list_push_back(&trigger->db->triggers, &trigger->node);
  41     trigger->request = request;
  42     trigger->result = NULL;
  43     trigger->created = now;
  44     trigger->timeout_msec = LLONG_MAX;
  45     trigger->read_only = read_only;
  46     trigger->role = nullable_xstrdup(role);
  47     trigger->id = nullable_xstrdup(id);
  48     ovsdb_trigger_try(trigger, now);
  49 }
  50
  51 void
  52 ovsdb_trigger_destroy(struct ovsdb_trigger *trigger)
  53 {
  54     ovs_list_remove(&trigger->node);
  55     json_destroy(trigger->request);
  56     json_destroy(trigger->result);
  57     free(trigger->role);
  58     free(trigger->id);
  59 }
  60
  61 bool
  62 ovsdb_trigger_is_complete(const struct ovsdb_trigger *trigger)
  63 {
  64     return trigger->result != NULL;
  65 }
  66
  67 struct json *
  68 ovsdb_trigger_steal_result(struct ovsdb_trigger *trigger)
  69 {
  70     struct json *result = trigger->result;
  71     trigger->result = NULL;
  72     return result;
  73 }
  74
  75 void
  76 ovsdb_trigger_run(struct ovsdb *db, long long int now)
  77 {
  78     struct ovsdb_trigger *t, *next;
  79     bool run_triggers;
  80
  81     run_triggers = db->run_triggers;
  82     db->run_triggers = false;
  83     LIST_FOR_EACH_SAFE (t, next, node, &db->triggers) {
  84         if (run_triggers || now - t->created >= t->timeout_msec) {
  85             ovsdb_trigger_try(t, now);
  86         }
  87     }
  88 }
  89
  90 void
  91 ovsdb_trigger_wait(struct ovsdb *db, long long int now)
  92 {
  93     if (db->run_triggers) {
  94         poll_immediate_wake();
  95     } else {
  96         long long int deadline = LLONG_MAX;
  97         struct ovsdb_trigger *t;
  98
  99         LIST_FOR_EACH (t, node, &db->triggers) {
 100             if (t->created < LLONG_MAX - t->timeout_msec) {
 101                 long long int t_deadline = t->created + t->timeout_msec;
 102                 if (deadline > t_deadline) {
 103                     deadline = t_deadline;
 104                     if (now >= deadline) {
 105                         break;
 106                     }
 107                 }
 108             }
 109         }
 110
 111         if (deadline < LLONG_MAX) {
 112             poll_timer_wait_until(deadline);
 113         }
 114     }
 115 }
 116
 117 static bool
 118 ovsdb_trigger_try(struct ovsdb_trigger *t, long long int now)
 119 {
 120     t->result = ovsdb_execute(t->db, t->session,
 121                               t->request, t->read_only,
 122                               t->role, t->id,
 123                               now - t->created, &t->timeout_msec);
 124     if (t->result) {
 125         ovsdb_trigger_complete(t);
 126         return true;
 127     } else {
 128         return false;
 129     }
 130 }
 131
 132 static void
 133 ovsdb_trigger_complete(struct ovsdb_trigger *t)
 134 {
 135     ovs_assert(t->result != NULL);
 136     ovs_list_remove(&t->node);
 137     ovs_list_push_back(&t->session->completions, &t->node);
 138 }