ovsdb: Provide helper function to determine if IDL has ever connected
[sliver-openvswitch.git] / lib / ovsdb-idl.c
index 32eddb1..a4407a5 100644 (file)
@@ -1,4 +1,4 @@
-/* Copyright (c) 2009 Nicira Networks.
+/* Copyright (c) 2009, 2010 Nicira Networks.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
 
 #include <assert.h>
 #include <errno.h>
+#include <inttypes.h>
 #include <limits.h>
 #include <stdlib.h>
 
 #include "bitmap.h"
+#include "dynamic-string.h"
 #include "json.h"
 #include "jsonrpc.h"
 #include "ovsdb-data.h"
 #include "ovsdb-error.h"
 #include "ovsdb-idl-provider.h"
+#include "poll-loop.h"
 #include "shash.h"
 #include "util.h"
 
@@ -78,6 +81,15 @@ struct ovsdb_idl_txn {
     struct ovsdb_idl *idl;
     struct hmap txn_rows;
     enum ovsdb_idl_txn_status status;
+    bool dry_run;
+    struct ds comment;
+
+    /* Increments. */
+    char *inc_table;
+    char *inc_column;
+    struct json *inc_where;
+    unsigned int inc_index;
+    int64_t inc_new_value;
 };
 
 static struct vlog_rate_limit syntax_rl = VLOG_RATE_LIMIT_INIT(1, 5);
@@ -212,6 +224,7 @@ ovsdb_idl_run(struct ovsdb_idl *idl)
 {
     int i;
 
+    assert(!idl->txn);
     jsonrpc_session_run(idl->session);
     for (i = 0; jsonrpc_session_is_connected(idl->session) && i < 50; i++) {
         struct jsonrpc_msg *msg, *reply;
@@ -231,9 +244,7 @@ ovsdb_idl_run(struct ovsdb_idl *idl)
         }
 
         reply = NULL;
-        if (msg->type == JSONRPC_REQUEST && !strcmp(msg->method, "echo")) {
-            reply = jsonrpc_create_reply(json_clone(msg->params), msg->id);
-        } else if (msg->type == JSONRPC_NOTIFY
+        if (msg->type == JSONRPC_NOTIFY
                    && !strcmp(msg->method, "update")
                    && msg->params->type == JSON_ARRAY
                    && msg->params->u.array.n == 2
@@ -280,6 +291,12 @@ ovsdb_idl_get_seqno(const struct ovsdb_idl *idl)
     return idl->change_seqno;
 }
 
+bool
+ovsdb_idl_has_ever_connected(const struct ovsdb_idl *idl)
+{
+    return ovsdb_idl_get_seqno(idl) != 0;
+}
+
 void
 ovsdb_idl_force_reconnect(struct ovsdb_idl *idl)
 {
@@ -598,7 +615,7 @@ ovsdb_idl_row_reparse_backrefs(struct ovsdb_idl_row *row, bool destroy_dsts)
 static struct ovsdb_idl_row *
 ovsdb_idl_row_create__(const struct ovsdb_idl_table_class *class)
 {
-    struct ovsdb_idl_row *row = xmalloc(class->allocation_size);
+    struct ovsdb_idl_row *row = xzalloc(class->allocation_size);
     memset(row, 0, sizeof *row);
     list_init(&row->src_arcs);
     list_init(&row->dst_arcs);
@@ -765,6 +782,8 @@ const char *
 ovsdb_idl_txn_status_to_string(enum ovsdb_idl_txn_status status)
 {
     switch (status) {
+    case TXN_UNCHANGED:
+        return "unchanged";
     case TXN_INCOMPLETE:
         return "incomplete";
     case TXN_ABORTED:
@@ -789,16 +808,61 @@ ovsdb_idl_txn_create(struct ovsdb_idl *idl)
     txn->idl = idl;
     txn->status = TXN_INCOMPLETE;
     hmap_init(&txn->txn_rows);
+    txn->dry_run = false;
+    ds_init(&txn->comment);
+    txn->inc_table = NULL;
+    txn->inc_column = NULL;
+    txn->inc_where = NULL;
     return txn;
 }
 
+void
+ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *txn, const char *s)
+{
+    if (txn->comment.length) {
+        ds_put_char(&txn->comment, '\n');
+    }
+    ds_put_cstr(&txn->comment, s);
+}
+
+void
+ovsdb_idl_txn_set_dry_run(struct ovsdb_idl_txn *txn)
+{
+    txn->dry_run = true;
+}
+
+void
+ovsdb_idl_txn_increment(struct ovsdb_idl_txn *txn, const char *table,
+                        const char *column, const struct json *where)
+{
+    assert(!txn->inc_table);
+    txn->inc_table = xstrdup(table);
+    txn->inc_column = xstrdup(column);
+    txn->inc_where = where ? json_clone(where) : json_array_create_empty();
+}
+
 void
 ovsdb_idl_txn_destroy(struct ovsdb_idl_txn *txn)
 {
+    if (txn->status == TXN_INCOMPLETE) {
+        hmap_remove(&txn->idl->outstanding_txns, &txn->hmap_node);
+    }
     ovsdb_idl_txn_abort(txn);
+    ds_destroy(&txn->comment);
+    free(txn->inc_table);
+    free(txn->inc_column);
+    json_destroy(txn->inc_where);
     free(txn);
 }
 
+void
+ovsdb_idl_txn_wait(const struct ovsdb_idl_txn *txn)
+{
+    if (txn->status != TXN_INCOMPLETE) {
+        poll_immediate_wake();
+    }
+}
+
 static struct json *
 where_uuid_equals(const struct uuid *uuid)
 {
@@ -889,6 +953,11 @@ ovsdb_idl_txn_disassemble(struct ovsdb_idl_txn *txn)
 
     HMAP_FOR_EACH_SAFE (row, next, struct ovsdb_idl_row, txn_node,
                         &txn->txn_rows) {
+        if (row->old && row->written) {
+            (row->table->class->unparse)(row);
+            ovsdb_idl_row_clear_arcs(row, false);
+            (row->table->class->parse)(row);
+        }
         ovsdb_idl_row_clear_new(row);
 
         free(row->prereqs);
@@ -910,7 +979,6 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
     struct ovsdb_idl_row *row;
     struct json *operations;
     bool any_updates;
-    enum ovsdb_idl_txn_status status;
 
     if (txn != txn->idl->txn) {
         return txn->status;
@@ -963,9 +1031,6 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
     any_updates = false;
     HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) {
         const struct ovsdb_idl_table_class *class = row->table->class;
-        size_t n_columns = class->n_columns;
-        struct json *row_json;
-        size_t idx;
 
         if (row->old == row->new) {
             continue;
@@ -975,62 +1040,116 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
             json_object_put_string(op, "table", class->name);
             json_object_put(op, "where", where_uuid_equals(&row->uuid));
             json_array_add(operations, op);
+            any_updates = true;
         } else {
-            row_json = NULL;
-            BITMAP_FOR_EACH_1 (idx, n_columns, row->written) {
+            struct json *row_json;
+            struct json *op;
+            size_t idx;
+
+            op = json_object_create();
+            json_object_put_string(op, "op", row->old ? "update" : "insert");
+            json_object_put_string(op, "table", class->name);
+            if (row->old) {
+                json_object_put(op, "where", where_uuid_equals(&row->uuid));
+            } else {
+                json_object_put(op, "uuid-name",
+                                json_string_create_nocopy(
+                                    uuid_name_from_uuid(&row->uuid)));
+            }
+            row_json = json_object_create();
+            json_object_put(op, "row", row_json);
+
+            BITMAP_FOR_EACH_1 (idx, class->n_columns, row->written) {
                 const struct ovsdb_idl_column *column = &class->columns[idx];
 
-                if (row->old
-                    && ovsdb_datum_equals(&row->old[idx], &row->new[idx],
-                                          &column->type)) {
-                    continue;
-                }
-                if (!row_json) {
-                    struct json *op = json_object_create();
-                    json_array_add(operations, op);
-                    json_object_put_string(op, "op",
-                                           row->old ? "update" : "insert");
-                    json_object_put_string(op, "table", class->name);
-                    if (row->old) {
-                        json_object_put(op, "where",
-                                        where_uuid_equals(&row->uuid));
-                    } else {
-                        json_object_put(op, "uuid-name",
-                                        json_string_create_nocopy(
-                                            uuid_name_from_uuid(&row->uuid)));
-                    }
-                    row_json = json_object_create();
-                    json_object_put(op, "row", row_json);
-                    any_updates = true;
+                if (!row->old || !ovsdb_datum_equals(&row->old[idx],
+                                                     &row->new[idx],
+                                                     &column->type)) {
+                    json_object_put(row_json, column->name,
+                                    substitute_uuids(
+                                        ovsdb_datum_to_json(&row->new[idx],
+                                                            &column->type),
+                                        txn));
                 }
-                json_object_put(row_json, column->name,
-                                substitute_uuids(
-                                    ovsdb_datum_to_json(&row->new[idx],
-                                                        &column->type),
-                                    txn));
+            }
+
+            if (!row->old || !shash_is_empty(json_object(row_json))) {
+                json_array_add(operations, op);
+                any_updates = true;
+            } else {
+                json_destroy(op);
             }
         }
     }
 
-    status = (!any_updates ? TXN_SUCCESS
-              : jsonrpc_session_send(
-                  txn->idl->session,
-                  jsonrpc_create_request(
-                      "transact", operations, &txn->request_id))
-              ? TXN_TRY_AGAIN
-              : TXN_INCOMPLETE);
+    /* Add increment. */
+    if (txn->inc_table && any_updates) {
+        struct json *op;
+
+        txn->inc_index = operations->u.array.n;
+
+        op = json_object_create();
+        json_object_put_string(op, "op", "mutate");
+        json_object_put_string(op, "table", txn->inc_table);
+        json_object_put(op, "where",
+                        substitute_uuids(json_clone(txn->inc_where), txn));
+        json_object_put(op, "mutations",
+                        json_array_create_1(
+                            json_array_create_3(
+                                json_string_create(txn->inc_column),
+                                json_string_create("+="),
+                                json_integer_create(1))));
+        json_array_add(operations, op);
+
+        op = json_object_create();
+        json_object_put_string(op, "op", "select");
+        json_object_put_string(op, "table", txn->inc_table);
+        json_object_put(op, "where",
+                        substitute_uuids(json_clone(txn->inc_where), txn));
+        json_object_put(op, "columns",
+                        json_array_create_1(json_string_create(
+                                                txn->inc_column)));
+        json_array_add(operations, op);
+    }
+
+    if (txn->comment.length) {
+        struct json *op = json_object_create();
+        json_object_put_string(op, "op", "comment");
+        json_object_put_string(op, "comment", ds_cstr(&txn->comment));
+        json_array_add(operations, op);
+    }
 
-    hmap_insert(&txn->idl->outstanding_txns, &txn->hmap_node,
-                json_hash(txn->request_id, 0));
-    txn->idl->txn = NULL;
+    if (txn->dry_run) {
+        struct json *op = json_object_create();
+        json_object_put_string(op, "op", "abort");
+        json_array_add(operations, op);
+    }
 
-    ovsdb_idl_txn_disassemble(txn);
-    if (status != TXN_INCOMPLETE) {
-        ovsdb_idl_txn_complete(txn, status);
+    if (!any_updates) {
+        txn->status = TXN_UNCHANGED;
+        json_destroy(operations);
+    } else if (!jsonrpc_session_send(
+                   txn->idl->session,
+                   jsonrpc_create_request(
+                       "transact", operations, &txn->request_id))) {
+        hmap_insert(&txn->idl->outstanding_txns, &txn->hmap_node,
+                    json_hash(txn->request_id, 0));
+    } else {
+        txn->status = TXN_INCOMPLETE;
     }
+
+    txn->idl->txn = NULL;
+    ovsdb_idl_txn_disassemble(txn);
     return txn->status;
 }
 
+int64_t
+ovsdb_idl_txn_get_increment_new_value(const struct ovsdb_idl_txn *txn)
+{
+    assert(txn->status == TXN_SUCCESS);
+    return txn->inc_new_value;
+}
+
 void
 ovsdb_idl_txn_abort(struct ovsdb_idl_txn *txn)
 {
@@ -1113,11 +1232,8 @@ ovsdb_idl_txn_delete(struct ovsdb_idl_row *row)
         hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node,
                     uuid_hash(&row->uuid));
     }
-    if (row->new == row->old) {
-        row->new = NULL;
-    } else {
-        ovsdb_idl_row_clear_new(row);
-    }
+    ovsdb_idl_row_clear_new(row);
+    row->new = NULL;
 }
 
 struct ovsdb_idl_row *
@@ -1158,6 +1274,75 @@ ovsdb_idl_txn_find(struct ovsdb_idl *idl, const struct json *id)
     return NULL;
 }
 
+static bool
+check_json_type(const struct json *json, enum json_type type, const char *name)
+{
+    if (!json) {
+        VLOG_WARN_RL(&syntax_rl, "%s is missing", name);
+        return false;
+    } else if (json->type != type) {
+        VLOG_WARN_RL(&syntax_rl, "%s is %s instead of %s",
+                     name, json_type_to_string(json->type),
+                     json_type_to_string(type));
+        return false;
+    } else {
+        return true;
+    }
+}
+
+static bool
+ovsdb_idl_txn_process_inc_reply(struct ovsdb_idl_txn *txn,
+                                const struct json_array *results)
+{
+    struct json *count, *rows, *row, *column;
+    struct shash *mutate, *select;
+
+    if (txn->inc_index + 2 > results->n) {
+        VLOG_WARN_RL(&syntax_rl, "reply does not contain enough operations "
+                     "for increment (has %u, needs %u)",
+                     results->n, txn->inc_index + 2);
+        return false;
+    }
+
+    /* We know that this is a JSON objects because the loop in
+     * ovsdb_idl_txn_process_reply() checked. */
+    mutate = json_object(results->elems[txn->inc_index]);
+    count = shash_find_data(mutate, "count");
+    if (!check_json_type(count, JSON_INTEGER, "\"mutate\" reply \"count\"")) {
+        return false;
+    }
+    if (count->u.integer != 1) {
+        VLOG_WARN_RL(&syntax_rl,
+                     "\"mutate\" reply \"count\" is %"PRId64" instead of 1",
+                     count->u.integer);
+        return false;
+    }
+
+    select = json_object(results->elems[txn->inc_index + 1]);
+    rows = shash_find_data(select, "rows");
+    if (!check_json_type(rows, JSON_ARRAY, "\"select\" reply \"rows\"")) {
+        return false;
+    }
+    if (rows->u.array.n != 1) {
+        VLOG_WARN_RL(&syntax_rl, "\"select\" reply \"rows\" has %u elements "
+                     "instead of 1",
+                     rows->u.array.n);
+        return false;
+    }
+    row = rows->u.array.elems[0];
+    if (!check_json_type(row, JSON_OBJECT, "\"select\" reply row")) {
+        return false;
+    }
+    column = shash_find_data(json_object(row), txn->inc_column);
+    if (!check_json_type(column, JSON_INTEGER,
+                         "\"select\" reply inc column")) {
+        return false;
+    }
+    txn->inc_new_value = column->u.integer;
+    return true;
+}
+
+
 static bool
 ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl,
                             const struct jsonrpc_msg *msg)
@@ -1195,7 +1380,7 @@ ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl,
                     if (error->type == JSON_STRING) {
                         if (!strcmp(error->u.string, "timed out")) {
                             soft_errors++;
-                        } else {
+                        } else if (strcmp(error->u.string, "aborted")) {
                             hard_errors++;
                         }
                     } else {
@@ -1211,6 +1396,14 @@ ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl,
             }
         }
 
+        if (txn->inc_table
+            && !soft_errors
+            && !hard_errors
+            && !ovsdb_idl_txn_process_inc_reply(txn,
+                                                json_array(msg->result))) {
+            hard_errors++;
+        }
+
         status = (hard_errors ? TXN_ERROR
                   : soft_errors ? TXN_TRY_AGAIN
                   : TXN_SUCCESS);
@@ -1219,3 +1412,11 @@ ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl,
     ovsdb_idl_txn_complete(txn, status);
     return true;
 }
+
+struct ovsdb_idl_txn *
+ovsdb_idl_txn_get(const struct ovsdb_idl_row *row)
+{
+    struct ovsdb_idl_txn *txn = row->table->idl->txn;
+    assert(txn != NULL);
+    return txn;
+}