/*
   Copyright (c) 2011-2012 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 <glusterfs/common-utils.h>
#include "cli1-xdr.h"
#include "xdr-generic.h"
#include "glusterd.h"
#include "glusterd-op-sm.h"
#include "glusterd-store.h"
#include "glusterd-utils.h"
#include "glusterd-volgen.h"
#include "glusterd-messages.h"
#include <glusterfs/syscall.h>

#include <signal.h>

int
__glusterd_handle_log_rotate(rpcsvc_request_t *req)
{
    int32_t ret = -1;
    gf_cli_req cli_req = {{
        0,
    }};
    dict_t *dict = NULL;
    glusterd_op_t cli_op = GD_OP_LOG_ROTATE;
    char *volname = NULL;
    char msg[64] = {
        0,
    };
    xlator_t *this = NULL;

    GF_ASSERT(req);
    this = THIS;
    GF_ASSERT(this);

    ret = xdr_to_generic(req->msg[0], &cli_req, (xdrproc_t)xdr_gf_cli_req);
    if (ret < 0) {
        // failed to decode msg;
        req->rpc_err = GARBAGE_ARGS;
        goto out;
    }

    if (cli_req.dict.dict_len) {
        /* Unserialize the dictionary */
        dict = dict_new();

        ret = dict_unserialize(cli_req.dict.dict_val, cli_req.dict.dict_len,
                               &dict);
        if (ret < 0) {
            gf_msg(this->name, GF_LOG_ERROR, 0, GD_MSG_DICT_UNSERIALIZE_FAIL,
                   "failed to "
                   "unserialize req-buffer to dictionary");
            snprintf(msg, sizeof(msg),
                     "Unable to decode the "
                     "command");
            goto out;
        }
    }

    ret = dict_get_str(dict, "volname", &volname);
    if (ret) {
        snprintf(msg, sizeof(msg), "Failed to get volume name");
        gf_msg(this->name, GF_LOG_ERROR, 0, GD_MSG_DICT_GET_FAILED, "%s", msg);
        goto out;
    }

    gf_msg(this->name, GF_LOG_INFO, 0, GD_MSG_LOG_ROTATE_REQ_RECVD,
           "Received log rotate req "
           "for volume %s",
           volname);

    ret = dict_set_uint64(dict, "rotate-key", (uint64_t)time(NULL));
    if (ret)
        goto out;

    ret = glusterd_op_begin_synctask(req, GD_OP_LOG_ROTATE, dict);

out:
    if (ret) {
        if (msg[0] == '\0')
            snprintf(msg, sizeof(msg), "Operation failed");
        ret = glusterd_op_send_cli_response(cli_op, ret, 0, req, dict, msg);
    }

    free(cli_req.dict.dict_val);
    return ret;
}

int
glusterd_handle_log_rotate(rpcsvc_request_t *req)
{
    return glusterd_big_locked_handler(req, __glusterd_handle_log_rotate);
}

/* op-sm */
int
glusterd_op_stage_log_rotate(dict_t *dict, char **op_errstr)
{
    int ret = -1;
    char *volname = NULL;
    glusterd_volinfo_t *volinfo = NULL;
    char msg[2048] = {0};
    char *brick = NULL;

    ret = dict_get_str(dict, "volname", &volname);
    if (ret) {
        gf_msg("glusterd", GF_LOG_ERROR, 0, GD_MSG_DICT_GET_FAILED,
               "Unable to get volume name");
        goto out;
    }

    ret = glusterd_volinfo_find(volname, &volinfo);
    if (ret) {
        snprintf(msg, sizeof(msg), "Volume %s does not exist", volname);
        gf_msg("glusterd", GF_LOG_ERROR, 0, GD_MSG_VOL_NOT_FOUND, "%s", msg);
        *op_errstr = gf_strdup(msg);
        goto out;
    }

    if (_gf_false == glusterd_is_volume_started(volinfo)) {
        snprintf(msg, sizeof(msg),
                 "Volume %s needs to be started before"
                 " log rotate.",
                 volname);
        gf_msg("glusterd", GF_LOG_ERROR, 0, GD_MSG_VOL_NOT_STARTED, "%s", msg);
        *op_errstr = gf_strdup(msg);
        ret = -1;
        goto out;
    }

    ret = dict_get_str(dict, "brick", &brick);
    /* If no brick is specified, do log-rotate for
       all the bricks in the volume */
    if (ret) {
        ret = 0;
        goto out;
    }

    ret = glusterd_volume_brickinfo_get_by_brick(brick, volinfo, NULL,
                                                 _gf_false);
    if (ret) {
        snprintf(msg, sizeof(msg),
                 "Incorrect brick %s "
                 "for volume %s",
                 brick, volname);
        gf_msg("glusterd", GF_LOG_ERROR, EINVAL, GD_MSG_INVALID_ENTRY, "%s",
               msg);
        *op_errstr = gf_strdup(msg);
        goto out;
    }
out:
    gf_msg_debug("glusterd", 0, "Returning %d", ret);

    return ret;
}

int
glusterd_op_log_rotate(dict_t *dict)
{
    int ret = -1;
    glusterd_conf_t *priv = NULL;
    glusterd_volinfo_t *volinfo = NULL;
    glusterd_brickinfo_t *brickinfo = NULL;
    xlator_t *this = NULL;
    char *volname = NULL;
    char *brick = NULL;
    char logfile[PATH_MAX] = {
        0,
    };
    char pidfile[PATH_MAX] = {
        0,
    };
    FILE *file = NULL;
    pid_t pid = 0;
    uint64_t key = 0;
    int valid_brick = 0;
    glusterd_brickinfo_t *tmpbrkinfo = NULL;

    this = THIS;
    GF_ASSERT(this);
    priv = this->private;
    GF_ASSERT(priv);

    ret = dict_get_str(dict, "volname", &volname);
    if (ret) {
        gf_msg("glusterd", GF_LOG_ERROR, 0, GD_MSG_DICT_GET_FAILED,
               "volname not found");
        goto out;
    }

    ret = dict_get_uint64(dict, "rotate-key", &key);
    if (ret) {
        gf_msg("glusterd", GF_LOG_ERROR, 0, GD_MSG_DICT_GET_FAILED,
               "rotate key not found");
        goto out;
    }

    ret = dict_get_str(dict, "brick", &brick);
    /* If no brick is specified, do log-rotate for
       all the bricks in the volume */
    if (ret)
        goto cont;

    ret = glusterd_brickinfo_new_from_brick(brick, &tmpbrkinfo, _gf_false,
                                            NULL);
    if (ret) {
        gf_msg("glusterd", GF_LOG_ERROR, 0, GD_MSG_BRICK_NOT_FOUND,
               "cannot get brickinfo from brick");
        goto out;
    }

cont:
    ret = glusterd_volinfo_find(volname, &volinfo);
    if (ret)
        goto out;

    ret = -1;
    cds_list_for_each_entry(brickinfo, &volinfo->bricks, brick_list)
    {
        if (gf_uuid_compare(brickinfo->uuid, MY_UUID))
            continue;

        if (tmpbrkinfo && brick &&
            (strcmp(tmpbrkinfo->hostname, brickinfo->hostname) ||
             strcmp(tmpbrkinfo->path, brickinfo->path)))
            continue;

        valid_brick = 1;

        GLUSTERD_GET_BRICK_PIDFILE(pidfile, volinfo, brickinfo, priv);
        file = fopen(pidfile, "r+");
        if (!file) {
            gf_msg("glusterd", GF_LOG_ERROR, errno, GD_MSG_FILE_OP_FAILED,
                   "Unable to open pidfile: %s", pidfile);
            ret = -1;
            goto out;
        }

        ret = fscanf(file, "%d", &pid);
        if (ret <= 0) {
            fclose(file);
            gf_msg("glusterd", GF_LOG_ERROR, errno, GD_MSG_FILE_OP_FAILED,
                   "Unable to read pidfile: %s", pidfile);
            ret = -1;
            goto out;
        }
        fclose(file);
        file = NULL;

        snprintf(logfile, PATH_MAX, "%s.%" PRIu64, brickinfo->logfile, key);

        ret = sys_rename(brickinfo->logfile, logfile);
        if (ret)
            gf_msg("glusterd", GF_LOG_WARNING, errno, GD_MSG_FILE_OP_FAILED,
                   "rename failed");

        ret = kill(pid, SIGHUP);
        if (ret) {
            gf_msg("glusterd", GF_LOG_ERROR, errno, GD_MSG_PID_KILL_FAIL,
                   "Unable to SIGHUP to %d", pid);
            goto out;
        }
        ret = 0;

        /* If request was for brick, only one iteration is enough */
        if (brick)
            break;
    }

    if (ret && !valid_brick)
        ret = 0;

out:
    if (tmpbrkinfo)
        glusterd_brickinfo_delete(tmpbrkinfo);

    return ret;
}