-/* Copyright (c) 2009, 2010 Nicira Networks
+/* Copyright (c) 2009, 2010, 2011 Nicira Networks
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
};
struct ovsdb_log {
+ off_t prev_offset;
off_t offset;
char *name;
struct lockfile *lockfile;
file->name = xstrdup(name);
file->lockfile = lockfile;
file->stream = stream;
+ file->prev_offset = 0;
file->offset = 0;
file->read_error = NULL;
file->write_error = NULL;
goto error;
}
+ file->prev_offset = file->offset;
file->offset = data_offset + data_length;
*jsonp = json;
return 0;
return error;
}
+/* Causes the log record read by the previous call to ovsdb_log_read() to be
+ * effectively discarded. The next call to ovsdb_log_write() will overwrite
+ * that previously read record.
+ *
+ * Calling this function more than once has no additional effect.
+ *
+ * This function is useful when ovsdb_log_read() successfully reads a record
+ * but that record does not make sense at a higher level (e.g. it specifies an
+ * invalid transaction). */
+void
+ovsdb_log_unread(struct ovsdb_log *file)
+{
+ assert(file->mode == OVSDB_LOG_READ);
+ file->offset = file->prev_offset;
+}
+
struct ovsdb_error *
ovsdb_log_write(struct ovsdb_log *file, struct json *json)
{