/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
 * Junior University
 * 
 * We are making the OpenFlow specification and associated documentation
 * (Software) available for public use and benefit with the expectation
 * that others will use, modify and enhance the Software and contribute
 * those enhancements back to the community. However, since we would
 * like to make the Software available for broadest use, with as few
 * restrictions as possible permission is hereby granted, free of
 * charge, to any person obtaining a copy of this Software to deal in
 * the Software under the copyrights without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 * 
 * The name and trademarks of copyright holder(s) may NOT be used in
 * advertising or publicity pertaining to the Software or any
 * derivatives without specific, written prior permission.
 */

#ifndef VLOG_H
#define VLOG_H 1

#include <stdbool.h>

/* Logging importance levels. */
enum vlog_level {
    VLL_EMER,
    VLL_ERR,
    VLL_WARN,
    VLL_DBG,
    VLL_N_LEVELS
};

const char *vlog_get_level_name(enum vlog_level);
enum vlog_level vlog_get_level_val(const char *name);

/* Facilities that we can log to. */
enum vlog_facility {
    VLF_SYSLOG,
    VLF_CONSOLE,
    VLF_N_FACILITIES,
    VLF_ANY_FACILITY = -1
};

const char *vlog_get_facility_name(enum vlog_facility);
enum vlog_facility vlog_get_facility_val(const char *name);

/* Modules that can emit log messages. */
#define VLOG_MODULES                            \
        VLOG_MODULE(chain)                      \
        VLOG_MODULE(controller)                 \
        VLOG_MODULE(ctlpath)                    \
        VLOG_MODULE(daemon)                     \
        VLOG_MODULE(datapath)                   \
        VLOG_MODULE(dhcp)                       \
        VLOG_MODULE(dhcp_client)                \
        VLOG_MODULE(dpif)                       \
        VLOG_MODULE(dpctl)                      \
        VLOG_MODULE(fault)                      \
        VLOG_MODULE(flow)                       \
        VLOG_MODULE(learning_switch)            \
        VLOG_MODULE(mac_learning)               \
        VLOG_MODULE(netdev)                     \
        VLOG_MODULE(netlink)                    \
        VLOG_MODULE(ofp_discover)               \
        VLOG_MODULE(poll_loop)                  \
        VLOG_MODULE(secchan)                    \
        VLOG_MODULE(rconn)                      \
        VLOG_MODULE(switch)                     \
        VLOG_MODULE(socket_util)                \
        VLOG_MODULE(vconn_netlink)              \
        VLOG_MODULE(vconn_tcp)                  \
        VLOG_MODULE(vconn_ssl)                  \
        VLOG_MODULE(vconn_stream)               \
        VLOG_MODULE(vconn_unix)                 \
        VLOG_MODULE(vconn)                      \
        VLOG_MODULE(vlog)                       \

/* VLM_ constant for each vlog module. */
enum vlog_module {
#define VLOG_MODULE(NAME) VLM_##NAME,
    VLOG_MODULES
#undef VLOG_MODULE
    VLM_N_MODULES,
    VLM_ANY_MODULE = -1
};

const char *vlog_get_module_name(enum vlog_module);
enum vlog_module vlog_get_module_val(const char *name);

/* Configuring how each module logs messages. */
enum vlog_level vlog_get_level(enum vlog_module, enum vlog_facility);
void vlog_set_levels(enum vlog_module, enum vlog_facility, enum vlog_level);
char *vlog_set_levels_from_string(const char *);
char *vlog_get_levels(void);
bool vlog_is_enabled(enum vlog_module, enum vlog_level);
void vlog_set_verbosity(const char *arg);

/* Function for actual logging. */
void vlog_init(void);
void vlog_exit(void);
void vlog(enum vlog_module, enum vlog_level, const char *format, ...)
    __attribute__((format(printf, 3, 4)));

/* Convenience macros.  To use these, define THIS_MODULE as a macro that
 * expands to the module used by the current source file, e.g.
 *      #include "vlog.h"
 *      #define THIS_MODULE VLM_netlink
 * Guaranteed to preserve errno.
 */
#define VLOG_EMER(...) vlog(THIS_MODULE, VLL_EMER, __VA_ARGS__)
#define VLOG_ERR(...) vlog(THIS_MODULE, VLL_ERR, __VA_ARGS__)
#define VLOG_WARN(...) vlog(THIS_MODULE, VLL_WARN, __VA_ARGS__)
#define VLOG_DBG(...) vlog(THIS_MODULE, VLL_DBG, __VA_ARGS__)

/* More convenience macros, for testing whether a given level is enabled in
 * THIS_MODULE.  When constructing a log message is expensive, this enables it
 * to be skipped. */
#define VLOG_IS_EMER_ENABLED() true
#define VLOG_IS_ERR_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_EMER)
#define VLOG_IS_WARN_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_WARN)
#define VLOG_IS_DBG_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_DBG)

#endif /* vlog.h */