lib/ovsdb-data.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_DATA_H
  17 #define OVSDB_DATA_H 1
  18
  19 #include <stdlib.h>
  20 #include "compiler.h"
  21 #include "ovsdb-types.h"
  22
  23 struct ds;
  24 struct ovsdb_symbol_table;
  25
  26 /* One value of an atomic type (given by enum ovs_atomic_type). */
  27 union ovsdb_atom {
  28     int64_t integer;
  29     double real;
  30     bool boolean;
  31     char *string;
  32     struct uuid uuid;
  33 };
  34
  35 void ovsdb_atom_init_default(union ovsdb_atom *, enum ovsdb_atomic_type);
  36 bool ovsdb_atom_is_default(const union ovsdb_atom *, enum ovsdb_atomic_type);
  37 void ovsdb_atom_clone(union ovsdb_atom *, const union ovsdb_atom *,
  38                       enum ovsdb_atomic_type);
  39 void ovsdb_atom_swap(union ovsdb_atom *, union ovsdb_atom *);
  40
  41 static inline bool
  42 ovsdb_atom_needs_destruction(enum ovsdb_atomic_type type)
  43 {
  44     return type == OVSDB_TYPE_STRING;
  45 }
  46
  47 static inline void
  48 ovsdb_atom_destroy(union ovsdb_atom *atom, enum ovsdb_atomic_type type)
  49 {
  50     if (type == OVSDB_TYPE_STRING) {
  51         free(atom->string);
  52     }
  53 }
  54
  55 uint32_t ovsdb_atom_hash(const union ovsdb_atom *, enum ovsdb_atomic_type,
  56                          uint32_t basis);
  57
  58 int ovsdb_atom_compare_3way(const union ovsdb_atom *,
  59                             const union ovsdb_atom *,
  60                             enum ovsdb_atomic_type);
  61
  62 static inline bool ovsdb_atom_equals(const union ovsdb_atom *a,
  63                                      const union ovsdb_atom *b,
  64                                      enum ovsdb_atomic_type type)
  65 {
  66     return !ovsdb_atom_compare_3way(a, b, type);
  67 }
  68
  69 struct ovsdb_error *ovsdb_atom_from_json(union ovsdb_atom *,
  70                                          const struct ovsdb_base_type *,
  71                                          const struct json *,
  72                                          struct ovsdb_symbol_table *)
  73     WARN_UNUSED_RESULT;
  74 struct json *ovsdb_atom_to_json(const union ovsdb_atom *,
  75                                 enum ovsdb_atomic_type);
  76
  77 char *ovsdb_atom_from_string(union ovsdb_atom *,
  78                              const struct ovsdb_base_type *, const char *)
  79     WARN_UNUSED_RESULT;
  80 void ovsdb_atom_to_string(const union ovsdb_atom *, enum ovsdb_atomic_type,
  81                           struct ds *);
  82
  83 struct ovsdb_error *ovsdb_atom_check_constraints(
  84     const union ovsdb_atom *, const struct ovsdb_base_type *)
  85     WARN_UNUSED_RESULT;
  86 \f
  87 /* An instance of an OVSDB type (given by struct ovsdb_type).
  88  *
  89  * - The 'keys' must be unique and in sorted order.  Most functions that modify
  90  *   an ovsdb_datum maintain these invariants.  Functions that don't maintain
  91  *   the invariants have names that end in "_unsafe".  Use ovsdb_datum_sort()
  92  *   to check and restore these invariants.
  93  *
  94  * - 'n' is constrained by the ovsdb_type's 'n_min' and 'n_max'.
  95  *
  96  *   If 'n' is nonzero, then 'keys' points to an array of 'n' atoms of the type
  97  *   specified by the ovsdb_type's 'key_type'.  (Otherwise, 'keys' should be
  98  *   null.)
  99  *
 100  *   If 'n' is nonzero and the ovsdb_type's 'value_type' is not
 101  *   OVSDB_TYPE_VOID, then 'values' points to an array of 'n' atoms of the type
 102  *   specified by the 'value_type'.  (Otherwise, 'values' should be null.)
 103  *
 104  *   Thus, for 'n' > 0, 'keys' will always be nonnull and 'values' will be
 105  *   nonnull only for "map" types.
 106  */
 107 struct ovsdb_datum {
 108     unsigned int n;             /* Number of 'keys' and 'values'. */
 109     union ovsdb_atom *keys;     /* Each of the ovsdb_type's 'key_type'. */
 110     union ovsdb_atom *values;   /* Each of the ovsdb_type's 'value_type'. */
 111 };
 112
 113 /* Basics. */
 114 void ovsdb_datum_init_empty(struct ovsdb_datum *);
 115 void ovsdb_datum_init_default(struct ovsdb_datum *, const struct ovsdb_type *);
 116 bool ovsdb_datum_is_default(const struct ovsdb_datum *,
 117                             const struct ovsdb_type *);
 118 void ovsdb_datum_clone(struct ovsdb_datum *, const struct ovsdb_datum *,
 119                        const struct ovsdb_type *);
 120 void ovsdb_datum_destroy(struct ovsdb_datum *, const struct ovsdb_type *);
 121 void ovsdb_datum_swap(struct ovsdb_datum *, struct ovsdb_datum *);
 122
 123 /* Checking and maintaining invariants. */
 124 struct ovsdb_error *ovsdb_datum_sort(struct ovsdb_datum *,
 125                                      const struct ovsdb_type *);
 126 struct ovsdb_error *ovsdb_datum_check_constraints(
 127     const struct ovsdb_datum *, const struct ovsdb_type *)
 128     WARN_UNUSED_RESULT;
 129
 130 /* Type conversion. */
 131 struct ovsdb_error *ovsdb_datum_from_json(struct ovsdb_datum *,
 132                                           const struct ovsdb_type *,
 133                                           const struct json *,
 134                                           struct ovsdb_symbol_table *)
 135     WARN_UNUSED_RESULT;
 136 struct json *ovsdb_datum_to_json(const struct ovsdb_datum *,
 137                                  const struct ovsdb_type *);
 138
 139 char *ovsdb_datum_from_string(struct ovsdb_datum *,
 140                              const struct ovsdb_type *, const char *)
 141     WARN_UNUSED_RESULT;
 142 void ovsdb_datum_to_string(const struct ovsdb_datum *,
 143                            const struct ovsdb_type *, struct ds *);
 144
 145 /* Comparison. */
 146 uint32_t ovsdb_datum_hash(const struct ovsdb_datum *,
 147                           const struct ovsdb_type *, uint32_t basis);
 148 int ovsdb_datum_compare_3way(const struct ovsdb_datum *,
 149                              const struct ovsdb_datum *,
 150                              const struct ovsdb_type *);
 151 bool ovsdb_datum_equals(const struct ovsdb_datum *,
 152                         const struct ovsdb_datum *,
 153                         const struct ovsdb_type *);
 154
 155 /* Search. */
 156 unsigned int ovsdb_datum_find_key(const struct ovsdb_datum *,
 157                                   const union ovsdb_atom *key,
 158                                   enum ovsdb_atomic_type key_type);
 159 unsigned int ovsdb_datum_find_key_value(const struct ovsdb_datum *,
 160                                         const union ovsdb_atom *key,
 161                                         enum ovsdb_atomic_type key_type,
 162                                         const union ovsdb_atom *value,
 163                                         enum ovsdb_atomic_type value_type);
 164
 165 /* Set operations. */
 166 bool ovsdb_datum_includes_all(const struct ovsdb_datum *,
 167                               const struct ovsdb_datum *,
 168                               const struct ovsdb_type *);
 169 bool ovsdb_datum_excludes_all(const struct ovsdb_datum *,
 170                               const struct ovsdb_datum *,
 171                               const struct ovsdb_type *);
 172 void ovsdb_datum_union(struct ovsdb_datum *,
 173                        const struct ovsdb_datum *,
 174                        const struct ovsdb_type *,
 175                        bool replace);
 176 void ovsdb_datum_subtract(struct ovsdb_datum *a,
 177                           const struct ovsdb_type *a_type,
 178                           const struct ovsdb_datum *b,
 179                           const struct ovsdb_type *b_type);
 180
 181 /* Raw operations that may not maintain the invariants. */
 182 void ovsdb_datum_remove_unsafe(struct ovsdb_datum *, size_t idx,
 183                                const struct ovsdb_type *);
 184 void ovsdb_datum_add_unsafe(struct ovsdb_datum *,
 185                             const union ovsdb_atom *key,
 186                             const union ovsdb_atom *value,
 187                             const struct ovsdb_type *);
 188
 189 /* Type checking. */
 190 static inline bool
 191 ovsdb_datum_conforms_to_type(const struct ovsdb_datum *datum,
 192                              const struct ovsdb_type *type)
 193 {
 194     return datum->n >= type->n_min && datum->n <= type->n_max;
 195 }
 196 \f
 197 /* A table mapping from names to data items.  Currently the data items are
 198  * always UUIDs; perhaps this will be expanded in the future. */
 199
 200 struct ovsdb_symbol {
 201     struct uuid uuid;           /* The UUID that the symbol represents. */
 202     bool used;                  /* Already used as row UUID? */
 203 };
 204
 205 struct ovsdb_symbol_table *ovsdb_symbol_table_create(void);
 206 void ovsdb_symbol_table_destroy(struct ovsdb_symbol_table *);
 207 struct ovsdb_symbol *ovsdb_symbol_table_get(const struct ovsdb_symbol_table *,
 208                                             const char *name);
 209 struct ovsdb_symbol *ovsdb_symbol_table_put(struct ovsdb_symbol_table *,
 210                                             const char *name,
 211                                             const struct uuid *, bool used);
 212 struct ovsdb_symbol *ovsdb_symbol_table_insert(struct ovsdb_symbol_table *,
 213                                                const char *name);
 214 \f
 215 /* Tokenization
 216  *
 217  * Used by ovsdb_atom_from_string() and ovsdb_datum_from_string(). */
 218
 219 char *ovsdb_token_parse(const char **, char **outp) WARN_UNUSED_RESULT;
 220 bool ovsdb_token_is_delim(unsigned char);
 221
 222 #endif /* ovsdb-data.h */