X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=ovsdb%2Ffile.c;h=c41872535d7b4f2612e02e2d18fe2ee396a7ebcc;hb=afe20d5c7092f31943e32ff2b9d99526fbfbc6cd;hp=377ca280f5bb57a8966421ba9d9b8fdd8ed35571;hpb=bd06962ad334fa4631b67905fc9f43f96a908915;p=openvswitch

diff --git a/ovsdb/file.c b/ovsdb/file.c
index 377ca280..c4187253 100644
--- a/ovsdb/file.c
+++ b/ovsdb/file.c
@@ -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.
@@ -20,6 +20,7 @@
 #include <assert.h>
 #include <fcntl.h>
 
+#include "bitmap.h"
 #include "column.h"
 #include "log.h"
 #include "json.h"
@@ -27,6 +28,7 @@
 #include "ovsdb-error.h"
 #include "row.h"
 #include "table.h"
+#include "timeval.h"
 #include "transaction.h"
 #include "uuid.h"
 #include "util.h"
@@ -34,21 +36,84 @@
 #define THIS_MODULE VLM_ovsdb_file
 #include "vlog.h"
 
+/* A transaction being converted to JSON for writing to a file. */
+struct ovsdb_file_txn {
+    struct json *json;          /* JSON for the whole transaction. */
+    struct json *table_json;    /* JSON for 'table''s transaction. */
+    struct ovsdb_table *table;  /* Table described in 'table_json'.  */
+};
+
+static void ovsdb_file_txn_init(struct ovsdb_file_txn *);
+static void ovsdb_file_txn_add_row(struct ovsdb_file_txn *,
+                                   const struct ovsdb_row *old,
+                                   const struct ovsdb_row *new,
+                                   const unsigned long int *changed);
+static struct ovsdb_error *ovsdb_file_txn_commit(struct json *,
+                                                 const char *comment,
+                                                 bool durable,
+                                                 struct ovsdb_log *);
+
+static struct ovsdb_error *ovsdb_file_open__(const char *file_name,
+                                             const struct ovsdb_schema *,
+                                             bool read_only, struct ovsdb **);
 static struct ovsdb_error *ovsdb_file_txn_from_json(struct ovsdb *,
                                                     const struct json *,
+                                                    bool converting,
                                                     struct ovsdb_txn **);
-static void ovsdb_file_replica_create(struct ovsdb *, struct ovsdb_log *);
+static void ovsdb_file_create(struct ovsdb *, struct ovsdb_log *);
 
+/* Opens database 'file_name' and stores a pointer to the new database in
+ * '*dbp'.  If 'read_only' is false, then the database will be locked and
+ * changes to the database will be written to disk.  If 'read_only' is true,
+ * the database will not be locked and changes to the database will persist
+ * only as long as the "struct ovsdb".
+ *
+ * On success, returns NULL.  On failure, returns an ovsdb_error (which the
+ * caller must destroy) and sets '*dbp' to NULL. */
 struct ovsdb_error *
 ovsdb_file_open(const char *file_name, bool read_only, struct ovsdb **dbp)
 {
+    return ovsdb_file_open__(file_name, NULL, read_only, dbp);
+}
+
+/* Opens database 'file_name' with an alternate schema.  The specified 'schema'
+ * is used to interpret the data in 'file_name', ignoring the schema actually
+ * stored in the file.  Data in the file for tables or columns that do not
+ * exist in 'schema' are ignored, but the ovsdb file format must otherwise be
+ * observed, including column constraints.
+ *
+ * This function can be useful for upgrading or downgrading databases to
+ * "almost-compatible" formats.
+ *
+ * The database will not be locked.  Changes to the database will persist only
+ * as long as the "struct ovsdb".
+ *
+ * On success, stores a pointer to the new database in '*dbp' and returns a
+ * null pointer.  On failure, returns an ovsdb_error (which the caller must
+ * destroy) and sets '*dbp' to NULL. */
+struct ovsdb_error *
+ovsdb_file_open_as_schema(const char *file_name,
+                          const struct ovsdb_schema *schema,
+                          struct ovsdb **dbp)
+{
+    return ovsdb_file_open__(file_name, schema, true, dbp);
+}
+
+static struct ovsdb_error *
+ovsdb_file_open__(const char *file_name,
+                  const struct ovsdb_schema *alternate_schema,
+                  bool read_only, struct ovsdb **dbp)
+{
+    enum ovsdb_log_open_mode open_mode;
     struct ovsdb_schema *schema;
     struct ovsdb_error *error;
     struct ovsdb_log *log;
     struct json *json;
     struct ovsdb *db;
 
-    error = ovsdb_log_open(file_name, read_only ? O_RDONLY : O_RDWR, &log);
+    *dbp = NULL;
+    open_mode = read_only ? OVSDB_LOG_READ_ONLY : OVSDB_LOG_READ_WRITE;
+    error = ovsdb_log_open(file_name, open_mode, -1, &log);
     if (error) {
         return error;
     }
@@ -61,12 +126,16 @@ ovsdb_file_open(const char *file_name, bool read_only, struct ovsdb **dbp)
                               file_name);
     }
 
-    error = ovsdb_schema_from_json(json, &schema);
-    if (error) {
-        json_destroy(json);
-        return ovsdb_wrap_error(error,
-                                "failed to parse \"%s\" as ovsdb schema",
-                                file_name);
+    if (alternate_schema) {
+        schema = ovsdb_schema_clone(alternate_schema);
+    } else {
+        error = ovsdb_schema_from_json(json, &schema);
+        if (error) {
+            json_destroy(json);
+            return ovsdb_wrap_error(error,
+                                    "failed to parse \"%s\" as ovsdb schema",
+                                    file_name);
+        }
     }
     json_destroy(json);
 
@@ -74,7 +143,8 @@ ovsdb_file_open(const char *file_name, bool read_only, struct ovsdb **dbp)
     while ((error = ovsdb_log_read(log, &json)) == NULL && json) {
         struct ovsdb_txn *txn;
 
-        error = ovsdb_file_txn_from_json(db, json, &txn);
+        error = ovsdb_file_txn_from_json(db, json, alternate_schema != NULL,
+                                         &txn);
         json_destroy(json);
         if (error) {
             break;
@@ -91,7 +161,7 @@ ovsdb_file_open(const char *file_name, bool read_only, struct ovsdb **dbp)
     }
 
     if (!read_only) {
-        ovsdb_file_replica_create(db, log);
+        ovsdb_file_create(db, log);
     } else {
         ovsdb_log_close(log);
     }
@@ -100,8 +170,47 @@ ovsdb_file_open(const char *file_name, bool read_only, struct ovsdb **dbp)
     return NULL;
 }
 
+static struct ovsdb_error *
+ovsdb_file_update_row_from_json(struct ovsdb_row *row, bool converting,
+                                const struct json *json)
+{
+    struct ovsdb_table_schema *schema = row->table->schema;
+    struct ovsdb_error *error;
+    struct shash_node *node;
+
+    if (json->type != JSON_OBJECT) {
+        return ovsdb_syntax_error(json, NULL, "row must be JSON object");
+    }
+
+    SHASH_FOR_EACH (node, json_object(json)) {
+        const char *column_name = node->name;
+        const struct ovsdb_column *column;
+        struct ovsdb_datum datum;
+
+        column = ovsdb_table_schema_get_column(schema, column_name);
+        if (!column) {
+            if (converting) {
+                continue;
+            }
+            return ovsdb_syntax_error(json, "unknown column",
+                                      "No column %s in table %s.",
+                                      column_name, schema->name);
+        }
+
+        error = ovsdb_datum_from_json(&datum, &column->type, node->data, NULL);
+        if (error) {
+            return error;
+        }
+        ovsdb_datum_swap(&row->fields[column->index], &datum);
+        ovsdb_datum_destroy(&datum, &column->type);
+    }
+
+    return NULL;
+}
+
 static struct ovsdb_error *
 ovsdb_file_txn_row_from_json(struct ovsdb_txn *txn, struct ovsdb_table *table,
+                             bool converting,
                              const struct uuid *row_uuid, struct json *json)
 {
     const struct ovsdb_row *row = ovsdb_table_get_row(table, row_uuid);
@@ -114,15 +223,15 @@ ovsdb_file_txn_row_from_json(struct ovsdb_txn *txn, struct ovsdb_table *table,
         ovsdb_txn_row_delete(txn, row);
         return NULL;
     } else if (row) {
-        return ovsdb_row_from_json(ovsdb_txn_row_modify(txn, row),
-                                   json, NULL, NULL);
+        return ovsdb_file_update_row_from_json(ovsdb_txn_row_modify(txn, row),
+                                               converting, json);
     } else {
         struct ovsdb_error *error;
         struct ovsdb_row *new;
 
         new = ovsdb_row_create(table);
         *ovsdb_row_get_uuid_rw(new) = *row_uuid;
-        error = ovsdb_row_from_json(new, json, NULL, NULL);
+        error = ovsdb_file_update_row_from_json(new, converting, json);
         if (error) {
             ovsdb_row_destroy(new);
         }
@@ -135,7 +244,8 @@ ovsdb_file_txn_row_from_json(struct ovsdb_txn *txn, struct ovsdb_table *table,
 
 static struct ovsdb_error *
 ovsdb_file_txn_table_from_json(struct ovsdb_txn *txn,
-                               struct ovsdb_table *table, struct json *json)
+                               struct ovsdb_table *table,
+                               bool converting, struct json *json)
 {
     struct shash_node *node;
 
@@ -154,8 +264,8 @@ ovsdb_file_txn_table_from_json(struct ovsdb_txn *txn,
                                       uuid_string);
         }
 
-        error = ovsdb_file_txn_row_from_json(txn, table, &row_uuid,
-                                             txn_row_json);
+        error = ovsdb_file_txn_row_from_json(txn, table, converting,
+                                             &row_uuid, txn_row_json);
         if (error) {
             return error;
         }
@@ -166,7 +276,7 @@ ovsdb_file_txn_table_from_json(struct ovsdb_txn *txn,
 
 static struct ovsdb_error *
 ovsdb_file_txn_from_json(struct ovsdb *db, const struct json *json,
-                         struct ovsdb_txn **txnp)
+                         bool converting, struct ovsdb_txn **txnp)
 {
     struct ovsdb_error *error;
     struct shash_node *node;
@@ -185,12 +295,19 @@ ovsdb_file_txn_from_json(struct ovsdb *db, const struct json *json,
 
         table = shash_find_data(&db->tables, table_name);
         if (!table) {
+            if (!strcmp(table_name, "_date")
+                || !strcmp(table_name, "_comment")
+                || converting) {
+                continue;
+            }
+
             error = ovsdb_syntax_error(json, "unknown table",
                                        "No table named %s.", table_name);
             goto error;
         }
 
-        error = ovsdb_file_txn_table_from_json(txn, table, txn_table_json);
+        error = ovsdb_file_txn_table_from_json(txn, table, converting,
+                                               txn_table_json);
         if (error) {
             goto error;
         }
@@ -202,45 +319,137 @@ error:
     ovsdb_txn_abort(txn);
     return error;
 }
+
+/* Saves a snapshot of 'db''s current contents as 'file_name'.  If 'comment' is
+ * nonnull, then it is added along with the data contents and can be viewed
+ * with "ovsdb-tool show-log".
+ *
+ * 'locking' is passed along to ovsdb_log_open() untouched. */
+struct ovsdb_error *
+ovsdb_file_save_copy(const char *file_name, int locking,
+                     const char *comment, const struct ovsdb *db)
+{
+    const struct shash_node *node;
+    struct ovsdb_file_txn ftxn;
+    struct ovsdb_error *error;
+    struct ovsdb_log *log;
+    struct json *json;
+
+    error = ovsdb_log_open(file_name, OVSDB_LOG_CREATE, locking, &log);
+    if (error) {
+        return error;
+    }
+
+    /* Write schema. */
+    json = ovsdb_schema_to_json(db->schema);
+    error = ovsdb_log_write(log, json);
+    json_destroy(json);
+    if (error) {
+        goto exit;
+    }
+
+    /* Write data. */
+    ovsdb_file_txn_init(&ftxn);
+    SHASH_FOR_EACH (node, &db->tables) {
+        const struct ovsdb_table *table = node->data;
+        const struct ovsdb_row *row;
+
+        HMAP_FOR_EACH (row, struct ovsdb_row, hmap_node, &table->rows) {
+            ovsdb_file_txn_add_row(&ftxn, NULL, row, NULL);
+        }
+    }
+    error = ovsdb_file_txn_commit(ftxn.json, comment, true, log);
+
+exit:
+    ovsdb_log_close(log);
+    if (error) {
+        remove(file_name);
+    }
+    return error;
+}
 
 /* Replica implementation. */
 
-struct ovsdb_file_replica {
+struct ovsdb_file {
     struct ovsdb_replica replica;
     struct ovsdb_log *log;
 };
 
-static const struct ovsdb_replica_class ovsdb_file_replica_class;
+static const struct ovsdb_replica_class ovsdb_file_class;
 
 static void
-ovsdb_file_replica_create(struct ovsdb *db, struct ovsdb_log *log)
+ovsdb_file_create(struct ovsdb *db, struct ovsdb_log *log)
 {
-    struct ovsdb_file_replica *r = xmalloc(sizeof *r);
-    ovsdb_replica_init(&r->replica, &ovsdb_file_replica_class);
-    r->log = log;
-    ovsdb_add_replica(db, &r->replica);
+    struct ovsdb_file *file = xmalloc(sizeof *file);
+    ovsdb_replica_init(&file->replica, &ovsdb_file_class);
+    file->log = log;
+    ovsdb_add_replica(db, &file->replica);
+}
 
+static struct ovsdb_file *
+ovsdb_file_cast(struct ovsdb_replica *replica)
+{
+    assert(replica->class == &ovsdb_file_class);
+    return CONTAINER_OF(replica, struct ovsdb_file, replica);
 }
 
-static struct ovsdb_file_replica *
-ovsdb_file_replica_cast(struct ovsdb_replica *replica)
+static bool
+ovsdb_file_change_cb(const struct ovsdb_row *old,
+                     const struct ovsdb_row *new,
+                     const unsigned long int *changed,
+                     void *ftxn_)
 {
-    assert(replica->class == &ovsdb_file_replica_class);
-    return CONTAINER_OF(replica, struct ovsdb_file_replica, replica);
+    struct ovsdb_file_txn *ftxn = ftxn_;
+    ovsdb_file_txn_add_row(ftxn, old, new, changed);
+    return true;
 }
 
-struct ovsdb_file_replica_aux {
-    struct json *json;          /* JSON for the whole transaction. */
-    struct json *table_json;    /* JSON for 'table''s transaction. */
-    struct ovsdb_table *table;  /* Table described in 'table_json'.  */
+static struct ovsdb_error *
+ovsdb_file_commit(struct ovsdb_replica *replica,
+                  const struct ovsdb_txn *txn, bool durable)
+{
+    struct ovsdb_file *file = ovsdb_file_cast(replica);
+    struct ovsdb_file_txn ftxn;
+
+    ovsdb_file_txn_init(&ftxn);
+    ovsdb_txn_for_each_change(txn, ovsdb_file_change_cb, &ftxn);
+    if (!ftxn.json) {
+        /* Nothing to commit. */
+        return NULL;
+    }
+
+    return ovsdb_file_txn_commit(ftxn.json, ovsdb_txn_get_comment(txn),
+                                 durable, file->log);
+}
+
+static void
+ovsdb_file_destroy(struct ovsdb_replica *replica)
+{
+    struct ovsdb_file *file = ovsdb_file_cast(replica);
+
+    ovsdb_log_close(file->log);
+    free(file);
+}
+
+static const struct ovsdb_replica_class ovsdb_file_class = {
+    ovsdb_file_commit,
+    ovsdb_file_destroy
 };
+
+static void
+ovsdb_file_txn_init(struct ovsdb_file_txn *ftxn)
+{
+    ftxn->json = NULL;
+    ftxn->table_json = NULL;
+    ftxn->table = NULL;
+}
 
-static bool
-ovsdb_file_replica_change_cb(const struct ovsdb_row *old,
-                             const struct ovsdb_row *new,
-                             void *aux_)
+static void
+ovsdb_file_txn_add_row(struct ovsdb_file_txn *ftxn,
+                       const struct ovsdb_row *old,
+                       const struct ovsdb_row *new,
+                       const unsigned long int *changed)
 {
-    struct ovsdb_file_replica_aux *aux = aux_;
     struct json *row;
 
     if (!new) {
@@ -248,15 +457,16 @@ ovsdb_file_replica_change_cb(const struct ovsdb_row *old,
     } else {
         struct shash_node *node;
 
-        row = NULL;
+        row = old ? NULL : json_object_create();
         SHASH_FOR_EACH (node, &new->table->schema->columns) {
             const struct ovsdb_column *column = node->data;
             const struct ovsdb_type *type = &column->type;
             unsigned int idx = column->index;
 
             if (idx != OVSDB_COL_UUID && column->persistent
-                && (!old || !ovsdb_datum_equals(&old->fields[idx],
-                                                &new->fields[idx], type)))
+                && (old
+                    ? bitmap_is_set(changed, idx)
+                    : !ovsdb_datum_is_default(&new->fields[idx], type)))
             {
                 if (!row) {
                     row = json_object_create();
@@ -271,53 +481,47 @@ ovsdb_file_replica_change_cb(const struct ovsdb_row *old,
         struct ovsdb_table *table = new ? new->table : old->table;
         char uuid[UUID_LEN + 1];
 
-        if (table != aux->table) {
+        if (table != ftxn->table) {
             /* Create JSON object for transaction overall. */
-            if (!aux->json) {
-                aux->json = json_object_create();
+            if (!ftxn->json) {
+                ftxn->json = json_object_create();
             }
 
             /* Create JSON object for transaction on this table. */
-            aux->table_json = json_object_create();
-            aux->table = table;
-            json_object_put(aux->json, table->schema->name, aux->table_json);
+            ftxn->table_json = json_object_create();
+            ftxn->table = table;
+            json_object_put(ftxn->json, table->schema->name, ftxn->table_json);
         }
 
         /* Add row to transaction for this table. */
         snprintf(uuid, sizeof uuid,
                  UUID_FMT, UUID_ARGS(ovsdb_row_get_uuid(new ? new : old)));
-        json_object_put(aux->table_json, uuid, row);
+        json_object_put(ftxn->table_json, uuid, row);
     }
-
-    return true;
 }
 
 static struct ovsdb_error *
-ovsdb_file_replica_commit(struct ovsdb_replica *r_,
-                          const struct ovsdb_txn *txn, bool durable)
+ovsdb_file_txn_commit(struct json *json, const char *comment,
+                      bool durable, struct ovsdb_log *log)
 {
-    struct ovsdb_file_replica *r = ovsdb_file_replica_cast(r_);
-    struct ovsdb_file_replica_aux aux;
     struct ovsdb_error *error;
 
-    aux.json = NULL;
-    aux.table_json = NULL;
-    aux.table = NULL;
-    ovsdb_txn_for_each_change(txn, ovsdb_file_replica_change_cb, &aux);
-
-    if (!aux.json) {
-        /* Nothing to commit. */
-        return NULL;
+    if (!json) {
+        json = json_object_create();
     }
+    if (comment) {
+        json_object_put_string(json, "_comment", comment);
+    }
+    json_object_put(json, "_date", json_integer_create(time_now()));
 
-    error = ovsdb_log_write(r->log, aux.json);
-    json_destroy(aux.json);
+    error = ovsdb_log_write(log, json);
+    json_destroy(json);
     if (error) {
         return ovsdb_wrap_error(error, "writing transaction failed");
     }
 
     if (durable) {
-        error = ovsdb_log_commit(r->log);
+        error = ovsdb_log_commit(log);
         if (error) {
             return ovsdb_wrap_error(error, "committing transaction failed");
         }
@@ -325,17 +529,3 @@ ovsdb_file_replica_commit(struct ovsdb_replica *r_,
 
     return NULL;
 }
-
-static void
-ovsdb_file_replica_destroy(struct ovsdb_replica *r_)
-{
-    struct ovsdb_file_replica *r = ovsdb_file_replica_cast(r_);
-
-    ovsdb_log_close(r->log);
-    free(r);
-}
-
-static const struct ovsdb_replica_class ovsdb_file_replica_class = {
-    ovsdb_file_replica_commit,
-    ovsdb_file_replica_destroy
-};