X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=ovsdb%2Flog.c;h=67043078f73da192f52971c771d5bcb101175042;hb=e51b8b03f936960d097fc642cb694d119829c054;hp=9c2767cb7206a05ed1efa245e925033f3efce99e;hpb=02dd3123a0e312f1d33403e744af52dd6096f12d;p=sliver-openvswitch.git diff --git a/ovsdb/log.c b/ovsdb/log.c index 9c2767cb7..67043078f 100644 --- a/ovsdb/log.c +++ b/ovsdb/log.c @@ -1,4 +1,4 @@ -/* 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. @@ -22,6 +22,7 @@ #include #include #include +#include #include #include "json.h" @@ -32,16 +33,17 @@ #include "socket-util.h" #include "transaction.h" #include "util.h" - -#define THIS_MODULE VLM_ovsdb_log #include "vlog.h" +VLOG_DEFINE_THIS_MODULE(ovsdb_log); + enum ovsdb_log_mode { OVSDB_LOG_READ, OVSDB_LOG_WRITE }; struct ovsdb_log { + off_t prev_offset; off_t offset; char *name; struct lockfile *lockfile; @@ -120,6 +122,7 @@ ovsdb_log_open(const char *name, enum ovsdb_log_open_mode open_mode, 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; @@ -283,6 +286,7 @@ ovsdb_log_read(struct ovsdb_log *file, struct json **jsonp) goto error; } + file->prev_offset = file->offset; file->offset = data_offset + data_length; *jsonp = json; return 0; @@ -293,6 +297,22 @@ error: 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) { @@ -369,3 +389,11 @@ ovsdb_log_commit(struct ovsdb_log *file) return 0; } +/* Returns the current offset into the file backing 'log', in bytes. This + * reflects the number of bytes that have been read or written in the file. If + * the whole file has been read, this is the file size. */ +off_t +ovsdb_log_get_offset(const struct ovsdb_log *log) +{ + return log->offset; +}