ovsdb/row.h

   1 /* Copyright (c) 2009, 2010 Nicira Networks
   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 #ifndef OVSDB_ROW_H
  17 #define OVSDB_ROW_H 1
  18
  19 #include <stddef.h>
  20 #include <stdint.h>
  21 #include "column.h"
  22 #include "hmap.h"
  23 #include "list.h"
  24 #include "ovsdb-data.h"
  25
  26 struct ovsdb_column_set;
  27
  28 /* A weak reference.
  29  *
  30  * When a column in row A contains a weak reference to UUID of a row B this
  31  * constitutes a weak reference from A (the source) to B (the destination).
  32  *
  33  * Rows A and B may be in the same table or different tables.
  34  *
  35  * Weak references from a row to itself are allowed, but no "struct
  36  * ovsdb_weak_ref" structures are created for them.
  37  */
  38 struct ovsdb_weak_ref {
  39     struct list src_node;       /* In src->src_refs list. */
  40     struct list dst_node;       /* In destination row's dst_refs list. */
  41     struct ovsdb_row *src;      /* Source row. */
  42 };
  43
  44 /* A row in a database table. */
  45 struct ovsdb_row {
  46     struct ovsdb_table *table;     /* Table to which this belongs. */
  47     struct hmap_node hmap_node;    /* Element in ovsdb_table's 'rows' hmap. */
  48     struct ovsdb_txn_row *txn_row; /* Transaction that row is in, if any. */
  49
  50     /* Weak references. */
  51     struct list src_refs;       /* Weak references from this row. */
  52     struct list dst_refs;       /* Weak references to this row. */
  53
  54     /* Number of strong refs to this row from other rows, in this table or
  55      * other tables, through 'uuid' columns that have a 'refTable' constraint
  56      * pointing to this table and a 'refType' of "strong".  A row with nonzero
  57      * 'n_refs' cannot be deleted.  Updated and checked only at transaction
  58      * commit. */
  59     size_t n_refs;
  60
  61     struct ovsdb_datum fields[];
  62 };
  63
  64 struct ovsdb_row *ovsdb_row_create(const struct ovsdb_table *);
  65 struct ovsdb_row *ovsdb_row_clone(const struct ovsdb_row *);
  66 void ovsdb_row_destroy(struct ovsdb_row *);
  67
  68 uint32_t ovsdb_row_hash_columns(const struct ovsdb_row *,
  69                                 const struct ovsdb_column_set *,
  70                                 uint32_t basis);
  71 bool ovsdb_row_equal_columns(const struct ovsdb_row *,
  72                              const struct ovsdb_row *,
  73                              const struct ovsdb_column_set *);
  74 int ovsdb_row_compare_columns_3way(const struct ovsdb_row *,
  75                                    const struct ovsdb_row *,
  76                                    const struct ovsdb_column_set *);
  77 void ovsdb_row_update_columns(struct ovsdb_row *, const struct ovsdb_row *,
  78                               const struct ovsdb_column_set *);
  79
  80 struct ovsdb_error *ovsdb_row_from_json(struct ovsdb_row *,
  81                                         const struct json *,
  82                                         struct ovsdb_symbol_table *,
  83                                         struct ovsdb_column_set *included)
  84     WARN_UNUSED_RESULT;
  85 struct json *ovsdb_row_to_json(const struct ovsdb_row *,
  86                                const struct ovsdb_column_set *include);
  87
  88 static inline const struct uuid *
  89 ovsdb_row_get_uuid(const struct ovsdb_row *row)
  90 {
  91     return &row->fields[OVSDB_COL_UUID].keys[0].uuid;
  92 }
  93
  94 static inline struct uuid *
  95 ovsdb_row_get_uuid_rw(struct ovsdb_row *row)
  96 {
  97     return &row->fields[OVSDB_COL_UUID].keys[0].uuid;
  98 }
  99
 100 static inline const struct uuid *
 101 ovsdb_row_get_version(const struct ovsdb_row *row)
 102 {
 103     return &row->fields[OVSDB_COL_VERSION].keys[0].uuid;
 104 }
 105
 106 static inline struct uuid *
 107 ovsdb_row_get_version_rw(struct ovsdb_row *row)
 108 {
 109     return &row->fields[OVSDB_COL_VERSION].keys[0].uuid;
 110 }
 111
 112 static inline uint32_t
 113 ovsdb_row_hash(const struct ovsdb_row *row)
 114 {
 115     return uuid_hash(ovsdb_row_get_uuid(row));
 116 }
 117 \f
 118 /* An unordered collection of rows. */
 119 struct ovsdb_row_set {
 120     const struct ovsdb_row **rows;
 121     size_t n_rows, allocated_rows;
 122 };
 123
 124 #define OVSDB_ROW_SET_INITIALIZER { NULL, 0, 0 }
 125
 126 void ovsdb_row_set_init(struct ovsdb_row_set *);
 127 void ovsdb_row_set_destroy(struct ovsdb_row_set *);
 128 void ovsdb_row_set_add_row(struct ovsdb_row_set *, const struct ovsdb_row *);
 129
 130 struct json *ovsdb_row_set_to_json(const struct ovsdb_row_set *,
 131                                    const struct ovsdb_column_set *);
 132
 133 void ovsdb_row_set_sort(struct ovsdb_row_set *,
 134                         const struct ovsdb_column_set *);
 135 \f
 136 /* A hash table of rows.  A specified set of columns is used for hashing and
 137  * comparing rows.
 138  *
 139  * The row hash doesn't necessarily own its rows.  They may be owned by, for
 140  * example, an ovsdb_table. */
 141 struct ovsdb_row_hash {
 142     struct hmap rows;
 143     struct ovsdb_column_set columns;
 144 };
 145
 146 #define OVSDB_ROW_HASH_INITIALIZER(RH) \
 147     { HMAP_INITIALIZER(&(RH).rows), OVSDB_COLUMN_SET_INITIALIZER }
 148
 149 struct ovsdb_row_hash_node {
 150     struct hmap_node hmap_node;
 151     const struct ovsdb_row *row;
 152 };
 153
 154 void ovsdb_row_hash_init(struct ovsdb_row_hash *,
 155                          const struct ovsdb_column_set *);
 156 void ovsdb_row_hash_destroy(struct ovsdb_row_hash *, bool destroy_rows);
 157 size_t ovsdb_row_hash_count(const struct ovsdb_row_hash *);
 158 bool ovsdb_row_hash_contains(const struct ovsdb_row_hash *,
 159                              const struct ovsdb_row *);
 160 bool ovsdb_row_hash_contains_all(const struct ovsdb_row_hash *,
 161                                  const struct ovsdb_row_hash *);
 162 bool ovsdb_row_hash_insert(struct ovsdb_row_hash *, const struct ovsdb_row *);
 163 bool ovsdb_row_hash_contains__(const struct ovsdb_row_hash *,
 164                                const struct ovsdb_row *, size_t hash);
 165 bool ovsdb_row_hash_insert__(struct ovsdb_row_hash *,
 166                              const struct ovsdb_row *, size_t hash);
 167
 168 #endif /* ovsdb/row.h */