/*
  Copyright (c) 2006-2009 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/>.
*/

#ifndef _CONFIG_H
#define _CONFIG_H
#include "config.h"
#endif

#include "server-protocol.h"
#include "server-helpers.h"



void
server_loc_wipe (loc_t *loc)
{
        if (loc->parent) {
                inode_unref (loc->parent);
                loc->parent = NULL;
        }

        if (loc->inode) {
                inode_unref (loc->inode);
                loc->inode = NULL;
        }

	if (loc->path)
		GF_FREE ((char *)loc->path);
}


void
server_resolve_wipe (server_resolve_t *resolve)
{
        struct resolve_comp *comp = NULL;
        int                  i = 0;

        if (resolve->path)
                GF_FREE (resolve->path);

        if (resolve->bname)
                GF_FREE (resolve->bname);

        if (resolve->resolved)
                GF_FREE (resolve->resolved);

        loc_wipe (&resolve->deep_loc);

        comp = resolve->components;
        if (comp) {
                for (i = 0; comp[i].basename; i++) {
                        if (comp[i].inode)
                                inode_unref (comp[i].inode);
                }
                GF_FREE (resolve->components);
        }
}


void
free_server_state (server_state_t *state)
{
        if (state->trans) {
                transport_unref (state->trans);
                state->trans = NULL;
        }

        if (state->fd) {
                fd_unref (state->fd);
                state->fd = NULL;
        }

        if (state->iobref) {
                iobref_unref (state->iobref);
                state->iobref = NULL;
        }

        if (state->iobuf) {
                iobuf_unref (state->iobuf);
                state->iobuf = NULL;
        }

        if (state->dict) {
                dict_unref (state->dict);
                state->dict = NULL;
        }

        if (state->volume)
                GF_FREE ((char *)state->volume);

        if (state->name)
                GF_FREE (state->name);

        server_loc_wipe (&state->loc);
        server_loc_wipe (&state->loc2);

        server_resolve_wipe (&state->resolve);
        server_resolve_wipe (&state->resolve2);

	GF_FREE (state);
}

static struct _lock_table *
gf_lock_table_new (void)
{
        struct _lock_table *new = NULL;

	new = GF_CALLOC (1, sizeof (struct _lock_table),
                         gf_server_mt_lock_table);
        if (new == NULL) {
                gf_log ("server-protocol", GF_LOG_CRITICAL,
                        "failed to allocate memory for new lock table");
                goto out;
        }
        INIT_LIST_HEAD (&new->dir_lockers);
        INIT_LIST_HEAD (&new->file_lockers);
        LOCK_INIT (&new->lock);
out:
        return new;
}


static int
gf_server_nop_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                   int32_t op_ret, int32_t op_errno)
{
        server_state_t *state = NULL;

        state = CALL_STATE(frame);

        if (state)
                free_state (state);
        STACK_DESTROY (frame->root);
        return 0;
}


static int
do_lock_table_cleanup (xlator_t *this, server_connection_t *conn,
                       call_frame_t *frame, struct _lock_table *ltable)
{
        struct list_head  file_lockers, dir_lockers;
        call_frame_t     *tmp_frame = NULL;
        struct flock      flock = {0, };
        xlator_t         *bound_xl = NULL;
        struct _locker   *locker = NULL, *tmp = NULL;
        int               ret = -1;

        bound_xl = conn->bound_xl;
        INIT_LIST_HEAD (&file_lockers);
        INIT_LIST_HEAD (&dir_lockers);

        LOCK (&ltable->lock);
        {
                list_splice_init (&ltable->file_lockers,
                                  &file_lockers);

                list_splice_init (&ltable->dir_lockers, &dir_lockers);
        }
        UNLOCK (&ltable->lock);

        GF_FREE (ltable);

        flock.l_type  = F_UNLCK;
        flock.l_start = 0;
        flock.l_len   = 0;
        list_for_each_entry_safe (locker,
                                  tmp, &file_lockers, lockers) {
                tmp_frame = copy_frame (frame);
                if (tmp_frame == NULL) {
                        gf_log (this->name, GF_LOG_ERROR,
                                "out of memory");
                        goto out;
                }
                /*
                   pid = 0 is a special case that tells posix-locks
                   to release all locks from this transport
                */
                tmp_frame->root->pid = 0;
                tmp_frame->root->trans = conn;

                if (locker->fd) {
                        STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                    bound_xl,
                                    bound_xl->fops->finodelk,
                                    locker->volume,
                                    locker->fd, F_SETLK, &flock);
                        fd_unref (locker->fd);
                } else {
                        STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                    bound_xl,
                                    bound_xl->fops->inodelk,
                                    locker->volume,
                                    &(locker->loc), F_SETLK, &flock);
                        loc_wipe (&locker->loc);
                }

                GF_FREE (locker->volume);
                
                list_del_init (&locker->lockers);
                GF_FREE (locker);
        }

        tmp = NULL;
        locker = NULL;
        list_for_each_entry_safe (locker, tmp, &dir_lockers, lockers) {
                tmp_frame = copy_frame (frame);

                tmp_frame->root->pid = 0;
                tmp_frame->root->trans = conn;

                if (locker->fd) {
                        STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                    bound_xl,
                                    bound_xl->fops->fentrylk,
                                    locker->volume,
                                    locker->fd, NULL,
                                    ENTRYLK_UNLOCK, ENTRYLK_WRLCK);
                        fd_unref (locker->fd);
                } else {
                        STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                    bound_xl,
                                    bound_xl->fops->entrylk,
                                    locker->volume,
                                    &(locker->loc), NULL,
                                    ENTRYLK_UNLOCK, ENTRYLK_WRLCK);
                        loc_wipe (&locker->loc);
                }

                GF_FREE (locker->volume);
                
                list_del_init (&locker->lockers);
                GF_FREE (locker);
        }
        ret = 0;

out:
        return ret;
}


static int
server_connection_cleanup_flush_cbk (call_frame_t *frame, void *cookie,
                                     xlator_t *this, int32_t op_ret,
                                     int32_t op_errno)
{
        fd_t *fd = NULL;

        fd = frame->local;

        fd_unref (fd);
        frame->local = NULL;

        STACK_DESTROY (frame->root);
        return 0;
}


static int
do_fd_cleanup (xlator_t *this, server_connection_t *conn, call_frame_t *frame,
               fdentry_t *fdentries, int fd_count)
{
        fd_t               *fd = NULL;
        int                 i = 0, ret = -1;
        call_frame_t       *tmp_frame = NULL;
        xlator_t           *bound_xl = NULL;

        bound_xl = conn->bound_xl;
        for (i = 0;i < fd_count; i++) {
                fd = fdentries[i].fd;

                if (fd != NULL) {
                        tmp_frame = copy_frame (frame);
                        if (tmp_frame == NULL) {
                                gf_log (this->name, GF_LOG_ERROR,
                                        "out of memory");
                                goto out;
                        }
                        tmp_frame->local = fd;

                        tmp_frame->root->pid = 0;
                        tmp_frame->root->trans = conn;
                        tmp_frame->root->lk_owner = 0;
                        STACK_WIND (tmp_frame,
                                    server_connection_cleanup_flush_cbk,
                                    bound_xl, bound_xl->fops->flush, fd);
                }
        }

        GF_FREE (fdentries);
        ret = 0;

out:
        return ret;
}

static int
do_connection_cleanup (xlator_t *this, server_connection_t *conn,
                       struct _lock_table *ltable, fdentry_t *fdentries, int fd_count)
{
        int             ret = 0;
        int             saved_ret = 0;
        call_frame_t   *frame = NULL;
        server_state_t *state = NULL;

        frame = create_frame (this, this->ctx->pool);
        if (frame == NULL) {
                gf_log (this->name, GF_LOG_ERROR, "out of memory");
                goto out;
        }

        saved_ret = do_lock_table_cleanup (this, conn, frame, ltable);

        if (fdentries != NULL) {
                ret = do_fd_cleanup (this, conn, frame, fdentries, fd_count);
        }

        state = CALL_STATE (frame);
        if (state)
                GF_FREE (state);

        STACK_DESTROY (frame->root);

        if (saved_ret || ret) {
                ret = -1;
        }

out:
        return ret;
}


int
gf_server_connection_cleanup (xlator_t *this, server_connection_t *conn)
{
        char                do_cleanup = 0;
        struct _lock_table *ltable = NULL;
        fdentry_t          *fdentries = NULL;
        uint32_t            fd_count = 0;
        int                 ret = 0; 

        if (conn == NULL) {
                goto out;
        }

        pthread_mutex_lock (&conn->lock);
        {
                conn->active_transports--;
                if (conn->active_transports == 0) {
                        if (conn->ltable) {
                                ltable = conn->ltable;
                                conn->ltable = gf_lock_table_new ();
                        }

                        if (conn->fdtable) {
                                fdentries = gf_fd_fdtable_get_all_fds (conn->fdtable,
                                                                       &fd_count);
                        }
                        do_cleanup = 1;
                }
        }
        pthread_mutex_unlock (&conn->lock);

        if (do_cleanup && conn->bound_xl)
                ret = do_connection_cleanup (this, conn, ltable, fdentries, fd_count);

out:
        return ret;
}


static int
server_connection_destroy (xlator_t *this, server_connection_t *conn)
{
        call_frame_t       *frame = NULL, *tmp_frame = NULL;
        xlator_t           *bound_xl = NULL;
        int32_t             ret = -1;
        server_state_t     *state = NULL;
        struct list_head    file_lockers;
        struct list_head    dir_lockers;
        struct _lock_table *ltable = NULL;
        struct _locker     *locker = NULL, *tmp = NULL;
        struct flock        flock = {0,};
        fd_t               *fd = NULL;
        int32_t             i = 0;
        fdentry_t          *fdentries = NULL;
        uint32_t             fd_count = 0;

        if (conn == NULL) {
                ret = 0;
                goto out;
        }

        bound_xl = (xlator_t *) (conn->bound_xl);

        if (bound_xl) {
                /* trans will have ref_count = 1 after this call, but its
                   ok since this function is called in
                   GF_EVENT_TRANSPORT_CLEANUP */
                frame = create_frame (this, this->ctx->pool);

                pthread_mutex_lock (&(conn->lock));
                {
                        if (conn->ltable) {
                                ltable = conn->ltable;
                                conn->ltable = NULL;
                        }
                }
                pthread_mutex_unlock (&conn->lock);

                INIT_LIST_HEAD (&file_lockers);
                INIT_LIST_HEAD (&dir_lockers);

                LOCK (&ltable->lock);
                {
                        list_splice_init (&ltable->file_lockers,
                                          &file_lockers);

                        list_splice_init (&ltable->dir_lockers, &dir_lockers);
                }
                UNLOCK (&ltable->lock);
                GF_FREE (ltable);

                flock.l_type  = F_UNLCK;
                flock.l_start = 0;
                flock.l_len   = 0;
                list_for_each_entry_safe (locker,
                                          tmp, &file_lockers, lockers) {
                        tmp_frame = copy_frame (frame);
                        /*
                           pid = 0 is a special case that tells posix-locks
                           to release all locks from this transport
                        */
                        tmp_frame->root->pid = 0;
                        tmp_frame->root->trans = conn;

                        if (locker->fd) {
                                STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                            bound_xl,
                                            bound_xl->fops->finodelk,
                                            locker->volume,
                                            locker->fd, F_SETLK, &flock);
                                fd_unref (locker->fd);
                        } else {
                                STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                            bound_xl,
                                            bound_xl->fops->inodelk,
                                            locker->volume,
                                            &(locker->loc), F_SETLK, &flock);
                                loc_wipe (&locker->loc);
                        }

                        GF_FREE (locker->volume);

			list_del_init (&locker->lockers);
			GF_FREE (locker);
		}

                tmp = NULL;
                locker = NULL;
                list_for_each_entry_safe (locker, tmp, &dir_lockers, lockers) {
                        tmp_frame = copy_frame (frame);

                        tmp_frame->root->pid = 0;
                        tmp_frame->root->trans = conn;

                        if (locker->fd) {
                                STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                            bound_xl,
                                            bound_xl->fops->fentrylk,
                                            locker->volume,
                                            locker->fd, NULL,
                                            ENTRYLK_UNLOCK, ENTRYLK_WRLCK);
                                fd_unref (locker->fd);
                        } else {
                                STACK_WIND (tmp_frame, gf_server_nop_cbk,
                                            bound_xl,
                                            bound_xl->fops->entrylk,
                                            locker->volume,
                                            &(locker->loc), NULL,
                                            ENTRYLK_UNLOCK, ENTRYLK_WRLCK);
                                loc_wipe (&locker->loc);
                        }

                        GF_FREE (locker->volume);


			list_del_init (&locker->lockers);
			GF_FREE (locker);
		}

                pthread_mutex_lock (&(conn->lock));
                {
                        if (conn->fdtable) {
                                fdentries = gf_fd_fdtable_get_all_fds (conn->fdtable,
                                                                       &fd_count);
                                gf_fd_fdtable_destroy (conn->fdtable);
                                conn->fdtable = NULL;
                        }
                }
                pthread_mutex_unlock (&conn->lock);

                if (fdentries != NULL) {
                        for (i = 0; i < fd_count; i++) {
                                fd = fdentries[i].fd;
                                if (fd != NULL) {
                                        tmp_frame = copy_frame (frame);
                                        tmp_frame->local = fd;

                                        STACK_WIND (tmp_frame,
                                                    server_connection_cleanup_flush_cbk,
                                                    bound_xl,
                                                    bound_xl->fops->flush,
                                                    fd);
                                }
                        }
                        GF_FREE (fdentries);
                }
        }

        if (frame) {
                state = CALL_STATE (frame);
                if (state)
                        GF_FREE (state);
                STACK_DESTROY (frame->root);
        }

        gf_log (this->name, GF_LOG_INFO, "destroyed connection of %s",
                conn->id);

	GF_FREE (conn->id);
	GF_FREE (conn);

out:
        return ret;
}


server_connection_t *
gf_server_connection_get (xlator_t *this, const char *id)
{
	server_connection_t *conn = NULL;
	server_connection_t *trav = NULL;
	server_conf_t       *conf = NULL;

        conf = this->private;

        pthread_mutex_lock (&conf->mutex);
        {
                list_for_each_entry (trav, &conf->conns, list) {
                        if (!strcmp (id, trav->id)) {
                                conn = trav;
                                break;
                        }
                }

		if (!conn) {
			conn = (void *) GF_CALLOC (1, sizeof (*conn),
                                        gf_server_mt_server_connection_t);

			conn->id = gf_strdup (id);
			conn->fdtable = gf_fd_fdtable_alloc ();
			conn->ltable  = gf_lock_table_new ();

                        pthread_mutex_init (&conn->lock, NULL);

			list_add (&conn->list, &conf->conns);
		}

                conn->ref++;
                conn->active_transports++;
	}
	pthread_mutex_unlock (&conf->mutex);

        return conn;
}


void
gf_server_connection_put (xlator_t *this, server_connection_t *conn)
{
        server_conf_t       *conf = NULL;
        server_connection_t *todel = NULL;

        if (conn == NULL) {
                goto out;
        }

        conf = this->private;

        pthread_mutex_lock (&conf->mutex);
        {
                conn->ref--;

                if (!conn->ref) {
                        list_del_init (&conn->list);
                        todel = conn;
                }
        }
        pthread_mutex_unlock (&conf->mutex);

        if (todel) {
                server_connection_destroy (this, todel);
        }

out:
        return;
}