ovsdb: refactor utility functions into separate file

Move local db access functions to a new file and make give them
global scope so they can be included in the ovsdb library and used
by other ovsdb library functions.

Signed-off-by: Lance Richardson <lrichard@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

1 files changed, 196 insertions, 0 deletions

diff --git a/ovsdb/ovsdb-util.c b/ovsdb/ovsdb-util.c
new file mode 100644
index 000000000..647f5df3e
--- /dev/null
+++ b/ovsdb/ovsdb-util.c
@@ -0,0 +1,196 @@
+/* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2016 Nicira, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+#include "row.h"
+#include "sset.h"
+#include "table.h"
+#include "ovsdb-util.h"
+#include "openvswitch/vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(ovsdb_util);
+
+struct ovsdb_datum *
+ovsdb_util_get_datum(struct ovsdb_row *row, const char *column_name,
+                    const enum ovsdb_atomic_type key_type,
+                    const enum ovsdb_atomic_type value_type,
+                    const size_t n_max)
+{
+    static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+    const struct ovsdb_table_schema *schema = row->table->schema;
+    const struct ovsdb_column *column;
+
+    column = ovsdb_table_schema_get_column(schema, column_name);
+    if (!column) {
+        VLOG_DBG_RL(&rl, "Table `%s' has no `%s' column",
+                    schema->name, column_name);
+        return NULL;
+    }
+
+    if (column->type.key.type != key_type
+        || column->type.value.type != value_type
+        || column->type.n_max != n_max) {
+        if (!VLOG_DROP_DBG(&rl)) {
+            char *type_name = ovsdb_type_to_english(&column->type);
+            VLOG_DBG("Table `%s' column `%s' has type %s, not expected "
+                     "key type %s, value type %s, max elements %"PRIuSIZE".",
+                     schema->name, column_name, type_name,
+                     ovsdb_atomic_type_to_string(key_type),
+                     ovsdb_atomic_type_to_string(value_type),
+                     n_max);
+            free(type_name);
+        }
+        return NULL;
+    }
+
+    return &row->fields[column->index];
+}
+
+/* Read string-string key-values from a map.  Returns the value associated with
+ * 'key', if found, or NULL */
+const char *
+ovsdb_util_read_map_string_column(const struct ovsdb_row *row,
+                                  const char *column_name,
+                                  const char *key)
+{
+    const struct ovsdb_datum *datum;
+    union ovsdb_atom *atom_key = NULL, *atom_value = NULL;
+    size_t i;
+
+    datum = ovsdb_util_get_datum(CONST_CAST(struct ovsdb_row *, row),
+                                 column_name, OVSDB_TYPE_STRING,
+                                 OVSDB_TYPE_STRING, UINT_MAX);
+
+    if (!datum) {
+        return NULL;
+    }
+
+    for (i = 0; i < datum->n; i++) {
+        atom_key = &datum->keys[i];
+        if (!strcmp(atom_key->string, key)) {
+            atom_value = &datum->values[i];
+            break;
+        }
+    }
+
+    return atom_value ? atom_value->string : NULL;
+}
+
+const union ovsdb_atom *
+ovsdb_util_read_column(const struct ovsdb_row *row, const char *column_name,
+                       enum ovsdb_atomic_type type)
+{
+    const struct ovsdb_datum *datum;
+
+    datum = ovsdb_util_get_datum(CONST_CAST(struct ovsdb_row *, row),
+                                 column_name, type, OVSDB_TYPE_VOID, 1);
+    return datum && datum->n ? datum->keys : NULL;
+}
+
+bool
+ovsdb_util_read_integer_column(const struct ovsdb_row *row,
+                               const char *column_name,
+                               long long int *integerp)
+{
+    const union ovsdb_atom *atom;
+
+    atom = ovsdb_util_read_column(row, column_name, OVSDB_TYPE_INTEGER);
+    *integerp = atom ? atom->integer : 0;
+    return atom != NULL;
+}
+
+bool
+ovsdb_util_read_string_column(const struct ovsdb_row *row,
+                              const char *column_name, const char **stringp)
+{
+    const union ovsdb_atom *atom;
+
+    atom = ovsdb_util_read_column(row, column_name, OVSDB_TYPE_STRING);
+    *stringp = atom ? atom->string : NULL;
+    return atom != NULL;
+}
+
+bool
+ovsdb_util_read_bool_column(const struct ovsdb_row *row,
+                            const char *column_name, bool *boolp)
+{
+    const union ovsdb_atom *atom;
+
+    atom = ovsdb_util_read_column(row, column_name, OVSDB_TYPE_BOOLEAN);
+    *boolp = atom ? atom->boolean : false;
+    return atom != NULL;
+}
+
+void
+ovsdb_util_write_bool_column(struct ovsdb_row *row, const char *column_name,
+                             bool value)
+{
+    const struct ovsdb_column *column;
+    struct ovsdb_datum *datum;
+
+    column = ovsdb_table_schema_get_column(row->table->schema, column_name);
+    datum = ovsdb_util_get_datum(row, column_name, OVSDB_TYPE_BOOLEAN,
+                                 OVSDB_TYPE_VOID, 1);
+    if (!datum) {
+        return;
+    }
+
+    if (datum->n != 1) {
+        ovsdb_datum_destroy(datum, &column->type);
+
+        datum->n = 1;
+        datum->keys = xmalloc(sizeof *datum->keys);
+        datum->values = NULL;
+    }
+
+    datum->keys[0].boolean = value;
+}
+
+void
+ovsdb_util_write_string_string_column(struct ovsdb_row *row,
+                                      const char *column_name,
+                                      char **keys, char **values, size_t n)
+{
+    const struct ovsdb_column *column;
+    struct ovsdb_datum *datum;
+    size_t i;
+
+    column = ovsdb_table_schema_get_column(row->table->schema, column_name);
+    datum = ovsdb_util_get_datum(row, column_name, OVSDB_TYPE_STRING,
+                                OVSDB_TYPE_STRING, UINT_MAX);
+    if (!datum) {
+        for (i = 0; i < n; i++) {
+            free(keys[i]);
+            free(values[i]);
+        }
+        return;
+    }
+
+    /* Free existing data. */
+    ovsdb_datum_destroy(datum, &column->type);
+
+    /* Allocate space for new values. */
+    datum->n = n;
+    datum->keys = xmalloc(n * sizeof *datum->keys);
+    datum->values = xmalloc(n * sizeof *datum->values);
+
+    for (i = 0; i < n; ++i) {
+        datum->keys[i].string = keys[i];
+        datum->values[i].string = values[i];
+    }
+
+    /* Sort and check constraints. */
+    ovsdb_datum_sort_assert(datum, column->type.key.type);
+}