/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Device allocation related work.
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/dkio.h>
#include <sys/wait.h>
#include <bsm/devalloc.h>

#define DEALLOCATE       "/usr/sbin/deallocate"
#define MKDEVALLOC      "/usr/sbin/mkdevalloc"

static char *_update_dev(deventry_t *, int, const char *, char *, char *);
static int _make_db();
extern int event_driven;


/*
 * _da_check_for_usb
 *      returns 1 if device pointed by 'link' is a removable hotplugged disk,
 *      else returns 0.
 */
int
_da_check_for_usb(char *link, char *root_dir)
{
        int             fd = -1;
        int             len, dstsize;
        int             removable = 0;
        int             hotpluggable = 0;
        char            *p = NULL;
        char            path[MAXPATHLEN + 4];
        char            rpath[MAXPATHLEN + 4];          /* for ",raw" */

        dstsize = sizeof (path);
        if (strcmp(root_dir, "") != 0) {
                if (strlcat(path, root_dir, dstsize) >= dstsize)
                        return (0);
                len = strlen(path);
        } else {
                len = 0;
        }
        (void) snprintf(path, dstsize - len, "%s", link);
        if ((p = realpath(path, rpath)) == NULL) {
                p = path;
        } else {
                if (strstr(link, "rdsk")) {
                        p = rpath;
                } else {
                        (void) snprintf(path, dstsize, "%s%s", rpath, ",raw");
                        p = path;
                }
        }
        if ((fd = open(p, O_RDONLY | O_NONBLOCK)) < 0)
                return (0);
        (void) ioctl(fd, DKIOCREMOVABLE, &removable);
        (void) ioctl(fd, DKIOCHOTPLUGGABLE, &hotpluggable);
        (void) close(fd);

        if (removable && hotpluggable)
                return (1);

        return (0);
}

/*
 * _reset_devalloc
 *      If device allocation is being turned on, creates device_allocate
 *      device_maps if they do not exist.
 *      Puts DEVICE_ALLOCATION=ON/OFF in device_allocate to indicate if
 *      device allocation is on/off.
 */
void
_reset_devalloc(int action)
{
        da_args dargs;

        if (action == DA_ON)
                (void) _make_db();
        else if ((action == DA_OFF) && (open(DEVALLOC, O_RDONLY) == -1))
                return;

        if (action == DA_ON)
                dargs.optflag = DA_ON;
        else if (action == DA_OFF)
                dargs.optflag = DA_OFF | DA_ALLOC_ONLY;

        dargs.rootdir = NULL;
        dargs.devnames = NULL;
        dargs.devinfo = NULL;

        (void) da_update_device(&dargs);
}

/*
 * _make_db
 *      execs /usr/sbin/mkdevalloc to create device_allocate and
 *      device_maps.
 */
static int
_make_db()
{
        int     status;
        pid_t   pid, wpid;

        pid = vfork();
        switch (pid) {
        case -1:
                return (1);
        case 0:
                if (execl(MKDEVALLOC, MKDEVALLOC, DA_IS_LABELED, NULL) == -1)
                        exit((errno == ENOENT) ? 0 : 1);
                return (1);
        default:
                for (;;) {
                        wpid = waitpid(pid, &status, 0);
                        if (wpid == (pid_t)-1) {
                                if (errno == EINTR)
                                        continue;
                                else
                                        return (1);
                        } else {
                                break;
                        }
                }
                break;
        }

        return ((WIFEXITED(status) == 0) ? 1 : WEXITSTATUS(status));
}


/*
 * _update_devalloc_db
 *      Forms allocatable device entries to be written to device_allocate and
 *      device_maps.
 *
 *      Or finds the correct entry to remove, and removes it.
 *
 *    Note: devname is a /devices link in the REMOVE case.
 */
/* ARGSUSED */
void
_update_devalloc_db(devlist_t *devlist, int devflag, int action, char *devname,
    char *root_dir)
{
        int             i;
        deventry_t      *entry = NULL, *dentry = NULL;
        char            *typestring;
        char            *nickname;  /* typestring + instance */

        if (action == DA_ADD) {
                for (i = 0; i < DA_COUNT; i++) {
                        switch (i) {
                        case 0:
                                dentry = devlist->audio;
                                break;
                        case 1:
                                dentry = devlist->cd;
                                break;
                        case 2:
                                dentry = devlist->floppy;
                                break;
                        case 3:
                                dentry = devlist->tape;
                                break;
                        case 4:
                                dentry = devlist->rmdisk;
                                break;
                        default:
                                return;
                        }
                        if (dentry)
                                (void) _update_dev(dentry, action, NULL, NULL,
                                    NULL);
                }
        } else if (action == DA_REMOVE) {
                if (devflag & DA_AUDIO) {
                        dentry = devlist->audio;
                        typestring = DA_AUDIO_TYPE;
                } else if (devflag & DA_CD) {
                        dentry = devlist->cd;
                        typestring = DA_CD_TYPE;
                } else if (devflag & DA_FLOPPY) {
                        dentry = devlist->floppy;
                        typestring = DA_FLOPPY_TYPE;
                } else if (devflag & DA_TAPE) {
                        dentry = devlist->tape;
                        typestring = DA_TAPE_TYPE;
                } else if (devflag & DA_RMDISK) {
                        dentry = devlist->rmdisk;
                        typestring = DA_RMDISK_TYPE;
                } else
                        return;

                if (event_driven) {
                        nickname = _update_dev(NULL, action, typestring, NULL,
                            devname);

                        if (nickname != NULL) {
                                (void) da_rm_list_entry(devlist, devname,
                                    devflag, nickname);
                                free(nickname);
                        }
                        return;
                }
                /*
                 * Not reached as of now, could be reached if devfsadm is
                 * enhanced to clean up devalloc database more thoroughly.
                 * Will not reliably match for event-driven removes
                 */
                for (entry = dentry; entry != NULL; entry = entry->next) {
                        if (strcmp(entry->devinfo.devname, devname) == 0)
                                break;
                }
                (void) _update_dev(entry, action, NULL, devname, NULL);
        }
}

/*
 *      _update_dev: Update device_allocate and/or device_maps files
 *
 *      If adding a device:
 *          dentry:     A linked list of allocatable devices
 *          action:     DA_ADD or DA_REMOVE
 *          devtype:    type of device linked list to update on removal
 *          devname:    short name (i.e. rmdisk5, cdrom0)  of device if known
 *          rm_link:    name of real /device from hot_cleanup
 *
 *      If the action is ADD or if the action is triggered by an event
 *      from syseventd,  read the files FIRST and treat their data as
 *      more-accurate than the dentry list, adjusting dentry contents if needed.
 *
 *      For DA_ADD, try to add each device in the list to the files.
 *
 *      If the action is DA_REMOVE and not a hotplug remove, adjust the files
 *      as indicated by the linked list.
 *
 *      RETURNS:
 *          If we successfully remove a device from the files,  returns
 *          a char * to strdup'd devname of the device removed.
 *
 *          The caller is responsible for freeing the return value.
 *
 *      NULL for all other cases, both success and failure.
 *
 */
static char *
_update_dev(deventry_t *dentry, int action, const char *devtype, char *devname,
    char *rm_link)
{
        da_args         dargs;
        deventry_t      newentry, *entry;
        int status;

        dargs.rootdir = NULL;
        dargs.devnames = NULL;

        if (event_driven)
                dargs.optflag = DA_EVENT;
        else
                dargs.optflag = 0;

        if (action == DA_ADD) {
                dargs.optflag |= DA_ADD;
                /*
                 * Add Events do not have enough information to overrride the
                 * existing file contents.
                 */

                for (entry = dentry; entry != NULL; entry = entry->next) {
                        dargs.devinfo = &(entry->devinfo);
                        (void) da_update_device(&dargs);
                }
        } else if (action == DA_REMOVE) {
                dargs.optflag |= DA_REMOVE;
                if (dentry) {
                        entry = dentry;
                } else if (dargs.optflag & DA_EVENT) {
                        if (devname == NULL)
                                newentry.devinfo.devname = NULL;
                        else
                                newentry.devinfo.devname = strdup(devname);
                        newentry.devinfo.devtype = (char *)devtype;
                        newentry.devinfo.devauths =
                            newentry.devinfo.devopts =
                            newentry.devinfo.devexec = NULL;
                        newentry.devinfo.devlist = strdup(rm_link);
                        newentry.devinfo.instance = 0;
                        newentry.next = NULL;
                        entry = &newentry;
                } else {
                        newentry.devinfo.devname = strdup(devname);
                        newentry.devinfo.devtype = (char *)devtype;
                        newentry.devinfo.devauths =
                            newentry.devinfo.devexec =
                            newentry.devinfo.devopts =
                            newentry.devinfo.devlist = NULL;
                        newentry.devinfo.instance = 0;
                        newentry.next = NULL;
                        entry = &newentry;
                }
                dargs.devinfo = &(entry->devinfo);
                /*
                 * da_update_device will fill in entry devname if
                 * event_driven is true and device is in the file
                 */
                status = da_update_device(&dargs);
                if (event_driven)
                        if (newentry.devinfo.devlist != NULL)
                                free(newentry.devinfo.devlist);
                if (status == 0)
                        return (dargs.devinfo->devname);
                else free(dargs.devinfo->devname);
        }
        return (NULL);
}