/*
 * 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 (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * Copyright 2019 Joyent, Inc.
 * Copyright 2025 Hans Rosenfeld
 */

#include <sys/types.h>
#include <sys/scsi/generic/commands.h>
#include <sys/scsi/impl/spc3_types.h>

#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <alloca.h>
#include <stdio.h>
#include <unistd.h>
#include <dlfcn.h>

#include <scsi/libscsi.h>
#include "libscsi_impl.h"

int
libscsi_assert(const char *expr, const char *file, int line)
{
        char *msg;
        size_t len;

        len = snprintf(NULL, 0,
            "ABORT: \"%s\", line %d: assertion failed: %s\n", file, line, expr);

        msg = alloca(len + 1);

        (void) snprintf(msg, len + 1,
            "ABORT: \"%s\", line %d: assertion failed: %s\n", file, line, expr);

        (void) write(STDERR_FILENO, msg, strlen(msg));

        abort();
        /*NOTREACHED*/
}

int
libscsi_set_errno(libscsi_hdl_t *hp, libscsi_errno_t err)
{
        hp->lsh_errno = err;
        hp->lsh_errmsg[0] = '\0';

        return (-1);
}

/*
 * Internal routine for setting both _ue_errno and _ue_errmsg.  We save
 * and restore the UNIX errno across this routing so the caller can use either
 * libscsi_set_errno(), libscsi_error(), or libscsi_verror() without this value
 * changing.
 */
int
libscsi_verror(libscsi_hdl_t *hp, libscsi_errno_t err, const char *fmt,
    va_list ap)
{
        size_t n;
        char *errmsg;

        /*
         * To allow the existing error message to itself be used in an error
         * message, we put the new error message into a buffer on the stack,
         * and then copy it into lsh_errmsg.  We also need to set the errno,
         * but because the call to libscsi_set_errno() is destructive to
         * lsh_errmsg, we do this after we print into our temporary buffer
         * (in case _libscsi_errmsg is part of the error message) and before we
         * copy the temporary buffer on to _libscsi_errmsg (to prevent our new
         * message from being nuked by the call to libscsi_set_errno()).
         */
        errmsg = alloca(sizeof (hp->lsh_errmsg));
        (void) vsnprintf(errmsg, sizeof (hp->lsh_errmsg), fmt, ap);
        (void) libscsi_set_errno(hp, err);

        n = strlen(errmsg);

        if (n != 0 && errmsg[n - 1] == '\n')
                errmsg[n - 1] = '\0';

        bcopy(errmsg, hp->lsh_errmsg, n + 1);

        return (-1);
}

/*PRINTFLIKE3*/
int
libscsi_error(libscsi_hdl_t *hp, libscsi_errno_t err, const char *fmt, ...)
{
        va_list ap;

        if (fmt == NULL)
                return (libscsi_set_errno(hp, err));

        va_start(ap, fmt);
        err = libscsi_verror(hp, err, fmt, ap);
        va_end(ap);

        return (err);
}

libscsi_errno_t
libscsi_errno(libscsi_hdl_t *hp)
{
        return (hp->lsh_errno);
}

const char *
libscsi_errmsg(libscsi_hdl_t *hp)
{
        if (hp->lsh_errmsg[0] == '\0')
                (void) strlcpy(hp->lsh_errmsg, libscsi_strerror(hp->lsh_errno),
                    sizeof (hp->lsh_errmsg));

        return (hp->lsh_errmsg);
}

void *
libscsi_alloc(libscsi_hdl_t *hp, size_t size)
{
        void *mem;

        if (size == 0) {
                (void) libscsi_set_errno(hp, ESCSI_ZERO_LENGTH);
                return (NULL);
        }

        if ((mem = malloc(size)) == NULL)
                (void) libscsi_set_errno(hp, ESCSI_NOMEM);

        return (mem);
}

void *
libscsi_zalloc(libscsi_hdl_t *hp, size_t size)
{
        void *mem;

        if ((mem = libscsi_alloc(hp, size)) == NULL)
                return (NULL);

        bzero(mem, size);

        return (mem);
}

char *
libscsi_strdup(libscsi_hdl_t *hp, const char *str)
{
        size_t len = strlen(str);
        char *dup = libscsi_alloc(hp, len + 1);

        if (dup == NULL)
                return (NULL);

        return (strcpy(dup, str));
}

/*ARGSUSED*/
void
libscsi_free(libscsi_hdl_t *hp, void *ptr)
{
        free(ptr);
}

libscsi_hdl_t *
libscsi_init(uint_t version, libscsi_errno_t *errp)
{
        libscsi_hdl_t *hp;

        if (version != LIBSCSI_VERSION) {
                if (errp != NULL)
                        *errp = ESCSI_VERSION;
                return (NULL);
        }

        if ((hp = malloc(sizeof (libscsi_hdl_t))) == NULL) {
                if (errp != NULL)
                        *errp = ESCSI_NOMEM;
                return (NULL);
        }

        bzero(hp, sizeof (libscsi_hdl_t));
        hp->lsh_version = version;

        return (hp);
}

void
libscsi_fini(libscsi_hdl_t *hp)
{
        libscsi_engine_impl_t *eip, *neip;

        if (hp == NULL)
                return;

        ASSERT(hp->lsh_targets == 0);

        for (eip = hp->lsh_engines; eip != NULL; eip = neip) {
                neip = eip->lsei_next;
                (void) dlclose(eip->lsei_dl_hdl);
                libscsi_free(hp, eip);
        }

        free(hp);
}

size_t
libscsi_cmd_cdblen(libscsi_hdl_t *hp, uint8_t cmd)
{
        size_t sz;

        switch (CDB_GROUPID(cmd)) {
        case CDB_GROUPID_0:
                sz = CDB_GROUP0;
                break;
        case CDB_GROUPID_1:
                sz = CDB_GROUP1;
                break;
        case CDB_GROUPID_2:
                sz = CDB_GROUP2;
                break;
        case CDB_GROUPID_3:
                sz = CDB_GROUP3;
                break;
        case CDB_GROUPID_4:
                sz = CDB_GROUP4;
                break;
        case CDB_GROUPID_5:
                sz = CDB_GROUP5;
                break;
        case CDB_GROUPID_6:
                sz = CDB_GROUP6;
                break;
        case CDB_GROUPID_7:
                sz = CDB_GROUP7;
                break;
        default:
                sz = 0;
        }

        if (sz == 0)
                (void) libscsi_error(hp, ESCSI_BADCMD,
                    "unknown or unsupported command %u", cmd);

        return (sz);
}

static char *
libscsi_process_inquiry_string(libscsi_hdl_t *hp, const char *raw, size_t len)
{
        char *buf;

        buf = alloca(len + 1);
        bcopy(raw, buf, len);

        for (; len > 0; len--) {
                if (buf[len - 1] != ' ')
                        break;
        }

        buf[len] = '\0';

        return (libscsi_strdup(hp, buf));
}

/*
 * As part of basic initialization, we always retrieve the INQUIRY information
 * to have the vendor/product/revision information available for all consumers.
 */
int
libscsi_get_inquiry(libscsi_hdl_t *hp, libscsi_target_t *tp)
{
        libscsi_action_t *ap;
        spc3_inquiry_cdb_t *cp;
        spc3_inquiry_data_t data;
        size_t len;

        if ((ap = libscsi_action_alloc(hp, SPC3_CMD_INQUIRY,
            LIBSCSI_AF_READ | LIBSCSI_AF_SILENT | LIBSCSI_AF_DIAGNOSE, &data,
            offsetof(spc3_inquiry_data_t, id_vs_36[0]))) == NULL)
                return (-1);

        cp = (spc3_inquiry_cdb_t *)libscsi_action_get_cdb(ap);

        SCSI_WRITE16(&cp->ic_allocation_length,
            offsetof(spc3_inquiry_data_t, id_vs_36[0]));

        if (libscsi_exec(ap, tp) != 0 ||
            libscsi_action_get_status(ap) != 0) {
                libscsi_action_free(ap);
                return (libscsi_set_errno(hp, ESCSI_INQUIRY_FAILED));
        }

        (void) libscsi_action_get_buffer(ap, NULL, NULL, &len);
        libscsi_action_free(ap);

        if (len < offsetof(spc3_inquiry_data_t, id_vs_36))
                return (libscsi_set_errno(hp, ESCSI_INQUIRY_FAILED));

        if ((tp->lst_vendor = libscsi_process_inquiry_string(hp,
            data.id_vendor_id, sizeof (data.id_vendor_id))) == NULL ||
            (tp->lst_product = libscsi_process_inquiry_string(hp,
            data.id_product_id, sizeof (data.id_product_id))) == NULL ||
            (tp->lst_revision = libscsi_process_inquiry_string(hp,
            data.id_product_revision,
            sizeof (data.id_product_revision))) == NULL) {
                return (-1);
        }

        return (0);
}

const char *
libscsi_vendor(libscsi_target_t *tp)
{
        return (tp->lst_vendor);
}

const char *
libscsi_product(libscsi_target_t *tp)
{
        return (tp->lst_product);
}

const char *
libscsi_revision(libscsi_target_t *tp)
{
        return (tp->lst_revision);
}