/*
  Copyright (c) 2016 Red Hat, Inc. <http://www.redhat.com>
  This file is part of GlusterFS.

  This file is licensed to you under your choice of the GNU Lesser
  General Public License, version 3 or any later version (LGPLv3 or
  later), or the GNU General Public License, version 2 (GPLv2), in all
  cases as published by the Free Software Foundation.
*/

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <stdarg.h>
#include <string.h>
#include <netinet/in.h>
#include <netdb.h>

#include "glusterfs/syscall.h"
#include "glusterfs/mem-pool.h"
#include "glusterfs/glusterfs.h"
#include "glusterfs/globals.h"
#include "glusterfs/events.h"

#define EVENT_HOST "127.0.0.1"
#define EVENT_PORT 24009

int
_gf_event(eventtypes_t event, const char *fmt, ...)
{
    int ret = 0;
    int sock = -1;
    char *eventstr = NULL;
    struct sockaddr_in server;
    va_list arguments;
    char *msg = NULL;
    glusterfs_ctx_t *ctx = NULL;
    char *host = NULL;
    struct addrinfo hints;
    struct addrinfo *result = NULL;
    xlator_t *this = THIS;
    int sin_family = AF_INET;
    char *volfile_server_transport = NULL;

    /* Global context */
    ctx = THIS->ctx;

    if (event < 0 || event >= EVENT_LAST) {
        ret = EVENT_ERROR_INVALID_INPUTS;
        goto out;
    }

    /* Initialize UDP socket */
    sock = socket(AF_INET, SOCK_DGRAM, 0);
    if (sock < 0) {
        ret = EVENT_ERROR_SOCKET;
        goto out;
    }

    memset(&hints, 0, sizeof(hints));
    hints.ai_family = AF_UNSPEC;

    if (ctx) {
        volfile_server_transport = ctx->cmd_args.volfile_server_transport;
    }

    if (!volfile_server_transport) {
        volfile_server_transport = "tcp";
    }
    /* Get Host name to send message */
    if (ctx && ctx->cmd_args.volfile_server &&
        (strcmp(volfile_server_transport, "unix"))) {
        /* If it is client code then volfile_server is set
           use that information to push the events. */
        if ((getaddrinfo(ctx->cmd_args.volfile_server, NULL, &hints,
                         &result)) != 0) {
            ret = EVENT_ERROR_RESOLVE;
            goto out;
        }

        if (get_ip_from_addrinfo(result, &host) == NULL) {
            ret = EVENT_ERROR_RESOLVE;
            goto out;
        }

        sin_family = result->ai_family;
    } else {
        /* Localhost, Use the defined IP for localhost */
        host = gf_strdup(EVENT_HOST);
    }

    /* Socket Configurations */
    server.sin_family = sin_family;
    server.sin_port = htons(EVENT_PORT);
    ret = inet_pton(server.sin_family, host, &server.sin_addr);
    if (ret <= 0) {
        gf_msg(this->name, GF_LOG_ERROR, EINVAL, LG_MSG_INVALID_ARG,
               "inet_pton failed with return code %d", ret);
        goto out;
    }
    memset(&server.sin_zero, '\0', sizeof(server.sin_zero));

    va_start(arguments, fmt);
    ret = gf_vasprintf(&msg, fmt, arguments);
    va_end(arguments);

    if (ret < 0) {
        ret = EVENT_ERROR_INVALID_INPUTS;
        goto out;
    }

    ret = gf_asprintf(&eventstr, "%u %d %s", (unsigned)time(NULL), event, msg);

    if (ret <= 0) {
        ret = EVENT_ERROR_MSG_FORMAT;
        goto out;
    }

    /* Send Message */
    if (sendto(sock, eventstr, strlen(eventstr), 0, (struct sockaddr *)&server,
               sizeof(server)) <= 0) {
        ret = EVENT_ERROR_SEND;
        goto out;
    }

    ret = EVENT_SEND_OK;

out:
    if (sock >= 0) {
        sys_close(sock);
    }

    /* Allocated by gf_vasprintf */
    if (msg)
        GF_FREE(msg);

    /* Allocated by gf_asprintf */
    if (eventstr)
        GF_FREE(eventstr);

    if (host)
        GF_FREE(host);

    if (result)
        freeaddrinfo(result);

    return ret;
}