/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <door.h>
#include <fcntl.h>
#include <syslog.h>
#include <sys/sunddi.h>
#include <libsysevent.h>
#include <picl.h>
#include <pthread.h>
#include "piclevent.h"
#include <sys/sysevent/eventdefs.h>
#include <sys/sysevent/dr.h>

#define PICLSLM_DOOR_FAILED     gettext("PICL SLM door create failed\n")

/*
 * syseventd event handler
 */
static  int     piclslm_debug = 0;
static  int     piclslm_deliver_event(sysevent_t *ev, int flag);
static  int     door_fd = -1;

typedef struct nvlist_queue {
        char                    *nvq_item;      /* packed nvlist */
        size_t                  nvq_sz;         /* buf size */
        struct nvlist_queue     *nvq_next;
} nvlist_queue_t;

static nvlist_queue_t   *nvq_head;
static nvlist_queue_t   *nvq_tail;

static mutex_t  nvq_lock;
static cond_t   nvq_cv;
static thread_t piclslm_deliver_thr_id;
static int      cleanup;

static struct slm_mod_ops piclslm_mod_ops = {
        SE_MAJOR_VERSION, SE_MINOR_VERSION, SE_MAX_RETRY_LIMIT,
        piclslm_deliver_event};


static void
init_queue(void)
{
        nvq_head = NULL;
        nvq_tail = NULL;
}

static int
add_to_queue(char *nvl, size_t sz)
{
        nvlist_queue_t  *new_nvq;

        new_nvq = malloc(sizeof (*new_nvq));
        if (new_nvq == NULL)
                return (-1);

        new_nvq->nvq_item = nvl;
        new_nvq->nvq_sz = sz;
        new_nvq->nvq_next = NULL;

        if (nvq_head == NULL)
                nvq_head = new_nvq;
        else
                nvq_tail->nvq_next = new_nvq;
        nvq_tail = new_nvq;

        return (0);
}

static nvlist_queue_t *
remove_from_queue(void)
{
        nvlist_queue_t  *nvqp;

        if (nvq_head == NULL)
                return (NULL);

        nvqp = nvq_head;
        nvq_head = nvq_head->nvq_next;
        if (nvq_head == NULL)
                nvq_tail = NULL;
        return (nvqp);
}

static void
free_nvqueue(nvlist_queue_t *nvqp)
{
        free(nvqp->nvq_item);
        free(nvqp);
}

/*
 * deliver the event to the plugin if the door exists
 */
static void
post_piclevent(char *pack_buf, size_t nvl_size)
{
        door_arg_t              darg;

        darg.data_ptr = pack_buf;
        darg.data_size = nvl_size;
        darg.desc_ptr = NULL;
        darg.desc_num = 0;
        darg.rbuf = NULL;
        darg.rsize = 0;

        if (door_fd < 0 || door_call(door_fd, &darg) < 0) {
                if (door_fd >= 0) {
                        if (errno != EBADF) {
                                return;
                        }

                        /*
                         * It's not a valid door file descriptor.
                         * Close and reopen the door and try again
                         * as "picld" may have restarted.
                         */
                        (void) close(door_fd);
                }

                door_fd = open(PICLEVENT_DOOR, O_RDONLY);
                if (piclslm_debug)
                        syslog(LOG_INFO,
                            "picl_slm: opened door %s door_fd: %d\n",
                            PICLEVENT_DOOR, door_fd);
                if (door_fd < 0 || door_call(door_fd, &darg) < 0) {
                        return;
                }
        }
        if (piclslm_debug)
                syslog(LOG_INFO,
                    "picl_slm: sent sysevent door:%d pack_buf:%p size:0x%x\n",
                    door_fd, pack_buf, nvl_size);
}

/*ARGSUSED*/
static void *
piclslm_deliver_thr(void *args)
{
        nvlist_queue_t          *nvqp;

        for (;;) {
                (void) mutex_lock(&nvq_lock);
                while (nvq_head == NULL && cleanup == 0) {
                        (void) cond_wait(&nvq_cv, &nvq_lock);
                }
                nvqp = remove_from_queue();
                (void) mutex_unlock(&nvq_lock);
                while (nvqp) {
                        post_piclevent(nvqp->nvq_item, nvqp->nvq_sz);
                        free_nvqueue(nvqp);
                        (void) mutex_lock(&nvq_lock);
                        nvqp = remove_from_queue();
                        (void) mutex_unlock(&nvq_lock);
                }
                if (cleanup)
                        return (NULL);
        }
        /*NOTREACHED*/
}

/*
 * returns 0 if arguments successfully added to nvl, EINVAL if arguments missing
 * from ev and EAGAIN if nvlist_add_string() fails
 */
static int
piclslm_add_ec_devfs_args(nvlist_t *nvl, sysevent_t *ev)
{
        sysevent_value_t se_val;

        if (sysevent_lookup_attr(ev, DEVFS_PATHNAME, SE_DATA_TYPE_STRING,
            &se_val) != 0 || se_val.value.sv_string == NULL) {
                return (EINVAL);
        }
        if (nvlist_add_string(nvl, PICLEVENTARG_DEVFS_PATH,
            se_val.value.sv_string)) {
                return (EAGAIN);
        }
        return (0);
}

/*
 * returns 0 if arguments successfully added to nvl, EINVAL if arguments missing
 * from ev and EAGAIN if nvlist_add_string() fails
 */
static int
piclslm_add_ec_dr_args(nvlist_t *nvl, sysevent_t *ev)
{
        sysevent_value_t se_val;

        if (sysevent_lookup_attr(ev, DR_AP_ID, SE_DATA_TYPE_STRING,
            &se_val) != 0 || se_val.value.sv_string == NULL) {
                return (EINVAL);
        }
        if (nvlist_add_string(nvl, PICLEVENTARG_AP_ID,
            se_val.value.sv_string)) {
                return (EAGAIN);
        }
        if (sysevent_lookup_attr(ev, DR_HINT, SE_DATA_TYPE_STRING,
            &se_val) != 0 || se_val.value.sv_string == NULL) {
                if (nvlist_add_string(nvl, PICLEVENTARG_HINT, ""))
                        return (EAGAIN);
        } else {
                if (nvlist_add_string(nvl, PICLEVENTARG_HINT,
                    se_val.value.sv_string))
                        return (EAGAIN);
        }
        return (0);
}

/*
 * returns 0 if arguments successfully added to nvl, EINVAL if arguments missing
 * from ev and EAGAIN if nvlist_add_string() fails
 */
static int
piclslm_add_ec_dr_req_args(nvlist_t *nvl, sysevent_t *ev)
{
        nvlist_t *nvlist = NULL;
        char *ap_id = NULL;
        char *dr_req = NULL;

        if (sysevent_get_attr_list(ev, &nvlist)) {
                return (EAGAIN);
        }

        if (nvlist_lookup_string(nvlist, DR_AP_ID, &ap_id) != 0 ||
            ap_id == NULL) {
                nvlist_free(nvlist);
                return (EINVAL);
        }

        if (nvlist_add_string(nvl, PICLEVENTARG_AP_ID, ap_id)) {
                nvlist_free(nvlist);
                return (EAGAIN);
        }

        dr_req = NULL;
        if (nvlist_lookup_string(nvlist, DR_REQ_TYPE, &dr_req) != 0)
                dr_req = "";

        if (nvlist_add_string(nvl, PICLEVENTARG_DR_REQ_TYPE, dr_req)) {
                nvlist_free(nvlist);
                return (EAGAIN);
        }

        if (piclslm_debug)
                syslog(LOG_DEBUG, "piclevent: dr_req_type = %s on %s\n",
                    (dr_req ? dr_req : "Investigate"), ap_id);

        nvlist_free(nvlist);
        return (0);
}

/*
 * piclslm_deliver_event - called by syseventd to deliver an event buffer.
 *                      The event buffer is subsequently delivered to
 *                      picld.  If picld, is not responding to the
 *                      delivery attempt, we will ignore it.
 */
/*ARGSUSED*/
static int
piclslm_deliver_event(sysevent_t *ev, int flag)
{
        sysevent_t      *dupev;
        nvlist_t        *nvl;
        char            *ec;
        char            *esc;
        char            *ename;
        int             retval;
        char            *pack_buf;
        size_t          nvl_size;
        int             rval;

        /*
         * Filter out uninteresting events
         */
        ec = sysevent_get_class_name(ev);
        esc = sysevent_get_subclass_name(ev);
        if (piclslm_debug)
                syslog(LOG_INFO,
                    "picl_slm: got sysevent  ev:%p class:%s subclass:%s\n",
                    ev, (ec) ? ec : "NULL", (esc) ? esc : "NULL");
        if ((ec == NULL) || (esc == NULL)) {
                return (0);
        } else if (strcmp(ec, EC_DEVFS) == 0) {
                if (strcmp(esc, ESC_DEVFS_DEVI_ADD) == 0)
                        ename = strdup(PICLEVENT_SYSEVENT_DEVICE_ADDED);
                else if (strcmp(esc, ESC_DEVFS_DEVI_REMOVE) == 0)
                        ename = strdup(PICLEVENT_SYSEVENT_DEVICE_REMOVED);
                else
                        return (0);
        } else if (strcmp(ec, EC_DR) == 0) {
                if (strcmp(esc, ESC_DR_AP_STATE_CHANGE) == 0)
                        ename = strdup(PICLEVENT_DR_AP_STATE_CHANGE);
                else if (strcmp(esc, ESC_DR_REQ) == 0)
                        ename = strdup(PICLEVENT_DR_REQ);
                else
                        return (0);
        } else {
                return (0);
        }

        if (ename == NULL)
                return (EAGAIN);

        /*
         * Make a copy to expand attribute list
         */
        dupev = sysevent_dup(ev);
        if (dupev == NULL) {
                free(ename);
                return (EAGAIN);
        }

        if (nvlist_alloc(&nvl, NV_UNIQUE_NAME_TYPE, 0)) {
                free(ename);
                sysevent_free(dupev);
                return (EAGAIN);
        }

        if (strcmp(ec, EC_DEVFS) == 0) {
                rval = piclslm_add_ec_devfs_args(nvl, dupev);
        } else if (strcmp(ec, EC_DR) == 0) {
                if (strcmp(esc, ESC_DR_REQ) == 0) {
                        rval = piclslm_add_ec_dr_req_args(nvl, dupev);
                } else {
                        rval = piclslm_add_ec_dr_args(nvl, dupev);
                }
        }

        if (rval != 0) {
                free(ename);
                nvlist_free(nvl);
                sysevent_free(dupev);
                return ((rval == EAGAIN) ? EAGAIN : 0);
        }

        pack_buf = NULL;
        if (nvlist_add_string(nvl, PICLEVENTARG_EVENT_NAME, ename) ||
            nvlist_add_string(nvl, PICLEVENTARG_DATA_TYPE,
            PICLEVENTARG_PICLEVENT_DATA) ||
            nvlist_pack(nvl, &pack_buf, &nvl_size, NV_ENCODE_NATIVE, 0)) {
                free(ename);
                nvlist_free(nvl);
                sysevent_free(dupev);
                return (EAGAIN);
        }

        /*
         * Add nvlist_t to queue
         */
        (void) mutex_lock(&nvq_lock);
        retval = add_to_queue(pack_buf, nvl_size);
        (void) cond_signal(&nvq_cv);
        (void) mutex_unlock(&nvq_lock);

        nvlist_free(nvl);
        sysevent_free(dupev);
        free(ename);
        return (retval < 0 ? EAGAIN : 0);
}

struct slm_mod_ops *
slm_init(void)
{
        cleanup = 0;

        init_queue();

        (void) mutex_init(&nvq_lock, USYNC_THREAD, NULL);
        (void) cond_init(&nvq_cv, USYNC_THREAD, NULL);

        if (thr_create(NULL, 0, piclslm_deliver_thr,
            NULL, THR_BOUND, &piclslm_deliver_thr_id) != 0) {
                (void) mutex_destroy(&nvq_lock);
                (void) cond_destroy(&nvq_cv);
                return (NULL);
        }
        return (&piclslm_mod_ops);
}

void
slm_fini(void)
{
        /*
         * Wait for all events to be sent
         */
        (void) mutex_lock(&nvq_lock);
        cleanup = 1;
        (void) cond_signal(&nvq_cv);
        (void) mutex_unlock(&nvq_lock);

        /* Wait for delivery thread to exit */
        (void) thr_join(piclslm_deliver_thr_id, NULL, NULL);

        (void) mutex_destroy(&nvq_lock);
        (void) cond_destroy(&nvq_cv);

        if (door_fd >= 0)
                (void) close(door_fd);
        door_fd = -1;
}