GDP

/* vim: set ai sw=4 sts=4 ts=4 : */

/*

**  LOG-MIRROR --- mirror a log

**

**                Cheap and dirty replication.

**

**        ----- BEGIN LICENSE BLOCK -----

**        Applications for the Global Data Plane

**        From the Ubiquitous Swarm Lab, 490 Cory Hall, U.C. Berkeley.

**

**        Copyright (c) 2015-2019, Regents of the University of California.

**        All rights reserved.

**

**        Permission is hereby granted, without written agreement and without

**        license or royalty fees, to use, copy, modify, and distribute this

**        software and its documentation for any purpose, provided that the above

**        copyright notice and the following two paragraphs appear in all copies

**        of this software.

**

**        IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,

**        SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST

**        PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION,

**        EVEN IF REGENTS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

**

**        REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT

**        LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS

**        FOR A PARTICULAR PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION,

**        IF ANY, PROVIDED HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO

**        OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,

**        OR MODIFICATIONS.

**        ----- END LICENSE BLOCK -----

*/

#include <gdp/gdp.h>

#include <ep/ep_app.h>

#include <ep/ep_dbg.h>

#include <sysexits.h>

void

usage(void)

{

        fprintf(stderr,

                        "Usage: %s [-D dbg_spec] [-G router_addr] source_log target_log\n"

                        "    -D  set debugging flags\n"

                        "    -G  IP host to contact for gdp_router\n",

                        ep_app_getprogname());

        exit(EX_USAGE);

}

int

main(int argc, char **argv)

{

        int opt;

        bool show_usage = false;

        EP_STAT estat;

        gdp_gin_t *igin, *ogin;

        char *gdpd_addr = NULL;

        const char *lname, *lmode;

        gdp_recno_t nextrecno;

        gdp_name_t gdpiname;

        gdp_event_t *gev;

        while ((opt = getopt(argc, argv, "D:G:")) > 0)

        {

                switch (opt)

                {

                 case 'D':

                        ep_dbg_set(optarg);

                        break;

                 case 'G':

                        gdpd_addr = optarg;

                        break;

                 default:

                        show_usage = true;

                        break;

                }

        }

        argc -= optind;

        argv += optind;

        if (show_usage || argc != 2)

                usage();

        // initialize GDP library

        estat = gdp_init(gdpd_addr);

        if (!EP_STAT_ISOK(estat))

        {

                ep_app_error("GDP Initialization failed");

                goto fail0;

        }

        // allow thread to settle to avoid interspersed debug output

        ep_time_nanosleep(INT64_C(100000000));

        // open target GCL (must already exist)

        lname = argv[1];

        lmode = "append";

        gdp_parse_name(argv[1], gdpiname);

        estat = gdp_gin_open(gdpiname, GDP_MODE_AO, NULL, &ogin);

        EP_STAT_CHECK(estat, goto fail1);

        nextrecno = gdp_gin_getnrecs(ogin) + 1;

        // open a source GCL with the provided name

        lname = argv[0];

        lmode = "read";

        gdp_parse_name(argv[0], gdpiname);

        estat = gdp_gin_open(gdpiname, GDP_MODE_RO, NULL, &igin);

        EP_STAT_CHECK(estat, goto fail1);

        // subscribe to input starting from the first recno target does not have

        estat = gdp_gin_subscribe_by_recno(igin, nextrecno, 0, NULL, NULL, NULL);

        EP_STAT_CHECK(estat, goto fail2);

        // copy forever

        while ((gev = gdp_event_next(igin, NULL)) != NULL)

        {

                switch (gdp_event_gettype(gev))

                {

                 case GDP_EVENT_DATA:

                        // copy the record to the new log

                        estat = gdp_gin_append(ogin, gdp_event_getdatum(gev), NULL);

                        EP_STAT_CHECK(estat, goto fail3);

                        break;

                 case GDP_EVENT_DONE:

                 case GDP_EVENT_SHUTDOWN:

                        ep_app_error("unexpected end of subscription");

                        estat = EP_STAT_END_OF_FILE;

                        goto fail2;

                 default:

                        // ignore

                        break;

                }

        }

fail3:

        ep_app_error("append failed");

fail2:

        // close GCLs / release resources

        //XXX someday

        if (false)

        {

fail1:

                ep_app_error("could not open %s for %s", lname, lmode);

        }

fail0:

        ep_app_message(estat, "exiting with status");

        return EP_STAT_ISOK(estat) ? EX_OK : EX_UNAVAILABLE;

}