/*
  Copyright (c) 2007-2011 Gluster, Inc. <http://www.gluster.com>
  This file is part of GlusterFS.

  GlusterFS is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published
  by the Free Software Foundation; either version 3 of the License,
  or (at your option) any later version.

  GlusterFS is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see
  <http://www.gnu.org/licenses/>.
*/

#include <libgen.h>
#include <unistd.h>
#include <fnmatch.h>
#include <sys/time.h>
#include <stdlib.h>
#include <signal.h>

#ifndef _CONFIG_H
#define _CONFIG_H
#include "config.h"
#endif
#include "afr-common.c"

struct volume_options options[];

int32_t
notify (xlator_t *this, int32_t event,
        void *data, ...)
{
        int ret = -1;

        ret = afr_notify (this, event, data);

        return ret;
}

int32_t
mem_acct_init (xlator_t *this)
{
        int     ret = -1;

        if (!this)
                return ret;

        ret = xlator_mem_acct_init (this, gf_afr_mt_end + 1);

        if (ret != 0) {
                gf_log(this->name, GF_LOG_ERROR, "Memory accounting init"
                       "failed");
                return ret;
        }

        return ret;
}


int
xlator_subvolume_index (xlator_t *this, xlator_t *subvol)
{
        int index = -1;
        int i = 0;
        xlator_list_t *list = NULL;

        list = this->children;

        while (list) {
                if (subvol == list->xlator ||
                    strcmp (subvol->name, list->xlator->name) == 0) {
                        index = i;
                        break;
                }
                list = list->next;
                i++;
        }

        return index;
}


int
xlator_subvolume_count (xlator_t *this)
{
        int i = 0;
        xlator_list_t *list = NULL;

        for (list = this->children; list; list = list->next)
                i++;
        return i;
}

void
fix_quorum_options (xlator_t *this, afr_private_t *priv, char *qtype)
{
        if (priv->quorum_count && strcmp(qtype,"fixed")) {
                gf_log(this->name,GF_LOG_WARNING,
                       "quorum-type %s overriding quorum-count %u",
                       qtype, priv->quorum_count);
        }
        if (!strcmp(qtype,"none")) {
                priv->quorum_count = 0;
        }
        else if (!strcmp(qtype,"auto")) {
                priv->quorum_count = AFR_QUORUM_AUTO;
        }
}

int
reconfigure (xlator_t *this, dict_t *options)
{
        afr_private_t *priv        = NULL;
        xlator_t      *read_subvol = NULL;
        int            ret         = -1;
        int            index       = -1;
        char          *qtype       = NULL;

        priv = this->private;

        GF_OPTION_RECONF ("background-self-heal-count",
                          priv->background_self_heal_count, options, uint32,
                          out);

        GF_OPTION_RECONF ("metadata-self-heal",
                          priv->metadata_self_heal, options, bool, out);

        GF_OPTION_RECONF ("data-self-heal", priv->data_self_heal, options, str,
                          out);

        GF_OPTION_RECONF ("entry-self-heal", priv->entry_self_heal, options,
                          bool, out);

        GF_OPTION_RECONF ("strict-readdir", priv->strict_readdir, options, bool,
                          out);

        GF_OPTION_RECONF ("data-self-heal-window-size",
                          priv->data_self_heal_window_size, options,
                          uint32, out);

        GF_OPTION_RECONF ("data-change-log", priv->data_change_log, options,
                          bool, out);

        GF_OPTION_RECONF ("metadata-change-log",
                          priv->metadata_change_log, options, bool, out);

        GF_OPTION_RECONF ("entry-change-log", priv->entry_change_log, options,
                          bool, out);

        GF_OPTION_RECONF ("data-self-heal-algorithm",
                          priv->data_self_heal_algorithm, options, str, out);

        GF_OPTION_RECONF ("self-heal-daemon", priv->shd.enabled, options, bool, out);

        GF_OPTION_RECONF ("read-subvolume", read_subvol, options, xlator, out);

        if (read_subvol) {
                index = xlator_subvolume_index (this, read_subvol);
                if (index == -1) {
                        gf_log (this->name, GF_LOG_ERROR, "%s not a subvolume",
                                read_subvol->name);
                        goto out;
                }
                priv->read_child = index;
        }

        GF_OPTION_RECONF ("quorum-type", qtype, options, str, out);
        GF_OPTION_RECONF ("quorum-count", priv->quorum_count, options,
                          uint32, out);
        fix_quorum_options(this,priv,qtype);

        ret = 0;
out:
        return ret;

}


static const char *favorite_child_warning_str = "You have specified subvolume '%s' "
        "as the 'favorite child'. This means that if a discrepancy in the content "
        "or attributes (ownership, permission, etc.) of a file is detected among "
        "the subvolumes, the file on '%s' will be considered the definitive "
        "version and its contents will OVERWRITE the contents of the file on other "
        "subvolumes. All versions of the file except that on '%s' "
        "WILL BE LOST.";


int32_t
init (xlator_t *this)
{
        afr_private_t *priv        = NULL;
        int            child_count = 0;
        xlator_list_t *trav        = NULL;
        int            i           = 0;
        int            ret         = -1;
        GF_UNUSED int  op_errno    = 0;
        xlator_t      *read_subvol = NULL;
        xlator_t      *fav_child   = NULL;
        char          *qtype       = NULL;

        if (!this->children) {
                gf_log (this->name, GF_LOG_ERROR,
                        "replicate translator needs more than one "
                        "subvolume defined.");
                return -1;
        }

        if (!this->parents) {
                gf_log (this->name, GF_LOG_WARNING,
                        "Volume is dangling.");
        }

        ALLOC_OR_GOTO (this->private, afr_private_t, out);

        priv = this->private;

        priv->read_child = -1;

        GF_OPTION_INIT ("read-subvolume", read_subvol, xlator, out);
        if (read_subvol) {
                priv->read_child = xlator_subvolume_index (this, read_subvol);
                if (priv->read_child == -1) {
                        gf_log (this->name, GF_LOG_ERROR, "%s not a subvolume",
                                read_subvol->name);
                        goto out;
                }
        }

        priv->favorite_child = -1;
        GF_OPTION_INIT ("favorite-child", fav_child, xlator, out);
        if (fav_child) {
                priv->favorite_child = xlator_subvolume_index (this, fav_child);
                if (priv->favorite_child == -1) {
                        gf_log (this->name, GF_LOG_ERROR, "%s not a subvolume",
                                fav_child->name);
                        goto out;
                }
                gf_log (this->name, GF_LOG_WARNING,
                        favorite_child_warning_str, fav_child->name,
                        fav_child->name, fav_child->name);
        }


        GF_OPTION_INIT ("background-self-heal-count",
                        priv->background_self_heal_count, uint32, out);

        GF_OPTION_INIT ("data-self-heal", priv->data_self_heal, str, out);

        GF_OPTION_INIT ("data-self-heal-algorithm",
                        priv->data_self_heal_algorithm, str, out);

        GF_OPTION_INIT ("data-self-heal-window-size",
                        priv->data_self_heal_window_size, uint32, out);

        GF_OPTION_INIT ("metadata-self-heal", priv->metadata_self_heal, bool,
                        out);

        GF_OPTION_INIT ("entry-self-heal", priv->entry_self_heal, bool, out);

        GF_OPTION_INIT ("self-heal-daemon", priv->shd.enabled, bool, out);

        GF_OPTION_INIT ("data-change-log", priv->data_change_log, bool, out);

        GF_OPTION_INIT ("metadata-change-log", priv->metadata_change_log, bool,
                        out);

        GF_OPTION_INIT ("entry-change-log", priv->entry_change_log, bool, out);

        GF_OPTION_INIT ("optimistic-change-log", priv->optimistic_change_log,
                        bool, out);

        GF_OPTION_INIT ("inodelk-trace", priv->inodelk_trace, bool, out);

        GF_OPTION_INIT ("entrylk-trace", priv->entrylk_trace, bool, out);

        GF_OPTION_INIT ("strict-readdir", priv->strict_readdir, bool, out);

        GF_OPTION_INIT ("quorum-type", qtype, str, out);
        GF_OPTION_INIT ("quorum-count", priv->quorum_count, uint32, out);
        fix_quorum_options(this,priv,qtype);

        priv->wait_count = 1;

        child_count = xlator_subvolume_count (this);

        priv->child_count = child_count;

        LOCK_INIT (&priv->lock);
        LOCK_INIT (&priv->read_child_lock);

        priv->child_up = GF_CALLOC (sizeof (unsigned char), child_count,
                                    gf_afr_mt_char);
        if (!priv->child_up) {
                ret = -ENOMEM;
                goto out;
        }

        for (i = 0; i < child_count; i++)
                priv->child_up[i] = -1; /* start with unknown state.
                                           this initialization needed
                                           for afr_notify() to work
                                           reliably
                                        */

        priv->children = GF_CALLOC (sizeof (xlator_t *), child_count,
                                    gf_afr_mt_xlator_t);
        if (!priv->children) {
                ret = -ENOMEM;
                goto out;
        }

        priv->pending_key = GF_CALLOC (sizeof (*priv->pending_key),
                                       child_count,
                                       gf_afr_mt_char);
        if (!priv->pending_key) {
                ret = -ENOMEM;
                goto out;
        }

        trav = this->children;
        i = 0;
        while (i < child_count) {
                priv->children[i] = trav->xlator;

                ret = gf_asprintf (&priv->pending_key[i], "%s.%s",
                                   AFR_XATTR_PREFIX,
                                   trav->xlator->name);
                if (-1 == ret) {
                        gf_log (this->name, GF_LOG_ERROR,
                                "asprintf failed to set pending key");
                        ret = -ENOMEM;
                        goto out;
                }

                trav = trav->next;
                i++;
        }

        priv->last_event = GF_CALLOC (child_count, sizeof (*priv->last_event),
                                      gf_afr_mt_int32_t);
        if (!priv->last_event) {
                ret = -ENOMEM;
                goto out;
        }

        priv->shd.pos = GF_CALLOC (sizeof (*priv->shd.pos), child_count,
                                   gf_afr_mt_afr_brick_pos_t);
        if (!priv->shd.pos) {
                ret = -ENOMEM;
                goto out;
        }

        LOCK_INIT (&priv->root_inode_lk);
        priv->first_lookup = 1;
        priv->root_inode = NULL;

        pthread_mutex_init (&priv->mutex, NULL);
        INIT_LIST_HEAD (&priv->saved_fds);

        ret = 0;
out:
        return ret;
}


int
fini (xlator_t *this)
{
        return 0;
}


struct xlator_fops fops = {
        .lookup      = afr_lookup,
        .open        = afr_open,
        .lk          = afr_lk,
        .flush       = afr_flush,
        .statfs      = afr_statfs,
        .fsync       = afr_fsync,
        .fsyncdir    = afr_fsyncdir,
        .xattrop     = afr_xattrop,
        .fxattrop    = afr_fxattrop,
        .inodelk     = afr_inodelk,
        .finodelk    = afr_finodelk,
        .entrylk     = afr_entrylk,
        .fentrylk    = afr_fentrylk,

        /* inode read */
        .access      = afr_access,
        .stat        = afr_stat,
        .fstat       = afr_fstat,
        .readlink    = afr_readlink,
        .getxattr    = afr_getxattr,
        .readv       = afr_readv,

        /* inode write */
        .writev      = afr_writev,
        .truncate    = afr_truncate,
        .ftruncate   = afr_ftruncate,
        .setxattr    = afr_setxattr,
        .setattr     = afr_setattr,
        .fsetattr    = afr_fsetattr,
        .removexattr = afr_removexattr,

        /* dir read */
        .opendir     = afr_opendir,
        .readdir     = afr_readdir,
        .readdirp    = afr_readdirp,

        /* dir write */
        .create      = afr_create,
        .mknod       = afr_mknod,
        .mkdir       = afr_mkdir,
        .unlink      = afr_unlink,
        .rmdir       = afr_rmdir,
        .link        = afr_link,
        .symlink     = afr_symlink,
        .rename      = afr_rename,
};


struct xlator_dumpops dumpops = {
        .priv       = afr_priv_dump,
};


struct xlator_cbks cbks = {
        .release     = afr_release,
        .releasedir  = afr_releasedir,
        .forget      = afr_forget,
};


struct volume_options options[] = {
        { .key  = {"read-subvolume" },
          .type = GF_OPTION_TYPE_XLATOR
        },
        { .key  = {"favorite-child"},
          .type = GF_OPTION_TYPE_XLATOR
        },
        { .key  = {"background-self-heal-count"},
          .type = GF_OPTION_TYPE_INT,
          .min  = 0,
          .default_value = "16",
        },
        { .key  = {"data-self-heal"},
          .type = GF_OPTION_TYPE_STR,
          .default_value = "",
          .value = {"1", "on", "yes", "true", "enable",
                    "0", "off", "no", "false", "disable",
                    "open"},
          .default_value = "on",
        },
        { .key  = {"data-self-heal-algorithm"},
          .type = GF_OPTION_TYPE_STR,
          .default_value = "",
          .description   = "Select between \"full\", \"diff\". The "
                           "\"full\" algorithm copies the entire file from "
                           "source to sink. The \"diff\" algorithm copies to "
                           "sink only those blocks whose checksums don't match "
                           "with those of source.",
          .value = { "diff", "full", "" }
        },
        { .key  = {"data-self-heal-window-size"},
          .type = GF_OPTION_TYPE_INT,
          .min  = 1,
          .max  = 1024,
          .default_value = "1",
          .description = "Maximum number blocks per file for which self-heal "
                         "process would be applied simultaneously."
        },
        { .key  = {"metadata-self-heal"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "on",
        },
        { .key  = {"entry-self-heal"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "on",
        },
        { .key  = {"data-change-log"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "on",
        },
        { .key  = {"metadata-change-log"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "on",
        },
        { .key  = {"entry-change-log"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "on",
        },
        { .key  = {"optimistic-change-log"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "on",
        },
        { .key  = {"strict-readdir"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "off",
        },
        { .key = {"inodelk-trace"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "off",
        },
        { .key = {"entrylk-trace"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "off",
        },
        { .key = {"self-heal-daemon"},
          .type = GF_OPTION_TYPE_BOOL,
          .default_value = "off",
        },
        { .key = {"quorum-type"},
          .type = GF_OPTION_TYPE_STR,
          .value = { "none", "auto", "fixed", "" },
          .default_value = "none",
          .description = "If value is \"fixed\" only allow writes if "
                         "quorum-count bricks are present.  If value is "
                         "\"auto\" only allow writes if more than half of "
                         "bricks, or exactly half including the first, are "
                         "present.",
        },
        { .key = {"quorum-count"},
          .type = GF_OPTION_TYPE_INT,
          .min = 1,
          .max = INT_MAX,
          .default_value = 0,
          .description = "If quorum-type is \"fixed\" only allow writes if "
                         "this many bricks or present.  Other quorum types "
                         "will OVERWRITE this value.",
        },
        { .key  = {NULL} },
};