/*      $OpenBSD: libscsi.c,v 1.11 2016/01/28 17:26:10 gsoares Exp $    */

/* Copyright (c) 1994 HD Associates
 * (contact: dufault@hda.com)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 * This product includes software developed by HD Associates
 * 4. Neither the name of the HD Associaates nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL HD ASSOCIATES OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      $FreeBSD: scsi.c,v 1.6 1995/05/30 05:47:26 rgrimes Exp $
 */
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <sys/scsiio.h>
#include <errno.h>
#include <stdarg.h>
#include <fcntl.h>

#include "libscsi.h"

static struct {
        FILE    *db_f;
        int     db_level;
        int     db_trunc;
} behave;

/* scsireq_reset: Reset a scsireq structure.
 */
scsireq_t *
scsireq_reset(scsireq_t *scsireq)
{
        if (scsireq == 0)
                return scsireq;

        scsireq->flags = 0;             /* info about the request status and type */
        scsireq->timeout = 2000;        /* 2 seconds */
        bzero(scsireq->cmd, sizeof(scsireq->cmd));
        scsireq->cmdlen = 0;
        /* Leave scsireq->databuf alone */
        /* Leave scsireq->datalen alone */
        scsireq->datalen_used = 0;
        bzero(scsireq->sense, sizeof(scsireq->sense));
        scsireq->senselen = sizeof(scsireq->sense);
        scsireq->senselen_used = 0;
        scsireq->status = 0;
        scsireq->retsts = 0;
        scsireq->error = 0;

        return scsireq;
}

/* scsireq_new: Allocate and initialize a new scsireq.
 */
scsireq_t *
scsireq_new(void)
{
        scsireq_t *p = malloc(sizeof(scsireq_t));

        if (p)
                scsireq_reset(p);

        return p;
}

/*
 * Decode: Decode the data section of a scsireq.  This decodes
 * trivial grammar:
 *
 * fields : field fields
 *        ;
 *
 * field : field_specifier
 *       | control
 *       ;
 *
 * control : 's' seek_value
 *       | 's' '+' seek_value
 *       ;
 *
 * seek_value : DECIMAL_NUMBER
 *       | 'v'                          // For indirect seek, i.e., value from the arg list
 *       ;
 *
 * field_specifier : type_specifier field_width
 *       | '{' NAME '}' type_specifier field_width
 *       ;
 *
 * field_width : DECIMAL_NUMBER
 *       ;
 *
 * type_specifier : 'i' // Integral types (i1, i2, i3, i4)
 *       | 'b'                          // Bits
 *       | 't'                          // Bits
 *       | 'c'                          // Character arrays
 *       | 'z'                          // Character arrays with zeroed trailing spaces
 *       ;
 *
 * Notes:
 * 1. Integral types are swapped into host order.
 * 2. Bit fields are allocated MSB to LSB to match the SCSI spec documentation.
 * 3. 's' permits "seeking" in the string.  "s+DECIMAL" seeks relative to
 *    DECIMAL; "sDECIMAL" seeks absolute to decimal.
 * 4. 's' permits an indirect reference.  "sv" or "s+v" will get the
 *    next integer value from the arg array.
 * 5. Field names can be anything between the braces
 *
 * BUGS:
 * i and b types are promoted to ints.
 *
 */
static int
do_buff_decode(u_char *databuf, size_t len,
    void (*arg_put)(void *, int , void *, int, char *),
    void *puthook, char *fmt, va_list ap)
{
        int assigned = 0;
        int width;
        int suppress;
        int plus;
        int done = 0;
        static u_char mask[] = {0, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
        int value;
        u_char *base = databuf;
        char letter;
        char field_name[80];

#       define ARG_PUT(ARG) \
        do \
        { \
                if (!suppress) { \
                        if (arg_put) \
                                (*arg_put)(puthook, (letter == 't' ? 'b' : letter), \
                                    (void *)((long)(ARG)), 1, field_name); \
                        else \
                                *(va_arg(ap, int *)) = (ARG); \
                        assigned++; \
                } \
                field_name[0] = 0; \
                suppress = 0; \
        } while (0)

        u_char bits = 0;        /* For bit fields */
        int shift = 0;          /* Bits already shifted out */
        suppress = 0;
        field_name[0] = 0;

        while (!done) {
                switch (letter = *fmt) {
                case ' ':       /* White space */
                case '\t':
                case '\r':
                case '\n':
                case '\f':
                        fmt++;
                        break;

                case '#':       /* Comment */
                        while (*fmt && (*fmt != '\n'))
                                fmt++;
                        if (fmt)
                                fmt++;  /* Skip '\n' */
                        break;

                case '*':       /* Suppress assignment */
                        fmt++;
                        suppress = 1;
                        break;

                case '{':       /* Field Name */
                        {
                                int i = 0;
                                fmt++;  /* Skip '{' */
                                while (*fmt && (*fmt != '}')) {
                                        if (i < sizeof(field_name)-1)
                                                field_name[i++] = *fmt;

                                        fmt++;
                                }
                                if (fmt)
                                        fmt++;  /* Skip '}' */
                                field_name[i] = 0;
                        }
                        break;

                case 't':       /* Bit (field) */
                case 'b':       /* Bits */
                        fmt++;
                        width = strtol(fmt, &fmt, 10);
                        if (width > 8)
                                done = 1;
                        else {
                                if (shift <= 0) {
                                        bits = *databuf++;
                                        shift = 8;
                                }
                                value = (bits >> (shift - width)) & mask[width];

#if 0
                                printf("shift %2d bits %02x value %02x width %2d mask %02x\n",
                                    shift, bits, value, width, mask[width]);
#endif

                                ARG_PUT(value);

                                shift -= width;
                        }

                        break;

                case 'i':       /* Integral values */
                        shift = 0;
                        fmt++;
                        width = strtol(fmt, &fmt, 10);
                        switch (width) {
                        case 1:
                                ARG_PUT(*databuf);
                                databuf++;
                                break;

                        case 2:
                                ARG_PUT((*databuf) << 8 | *(databuf + 1));
                                databuf += 2;
                                break;

                        case 3:
                                ARG_PUT(
                                    (*databuf) << 16 |
                                    (*(databuf + 1)) << 8 |
                                    *(databuf + 2));
                                databuf += 3;
                                break;

                        case 4:
                                ARG_PUT(
                                    (*databuf) << 24 |
                                    (*(databuf + 1)) << 16 |
                                    (*(databuf + 2)) << 8 |
                                    *(databuf + 3));
                                databuf += 4;
                                break;

                                default:
                                done = 1;
                        }

                        break;

                case 'c':       /* Characters (i.e., not swapped) */
                case 'z':       /* Characters with zeroed trailing spaces  */
                        shift = 0;
                        fmt++;
                        width = strtol(fmt, &fmt, 10);
                        if (!suppress) {
                                if (arg_put)
                                        (*arg_put)(puthook, (letter == 't' ? 'b' : letter),
                                            databuf, width, field_name);
                                else {
                                        char *dest;
                                        dest = va_arg(ap, char *);
                                        bcopy(databuf, dest, width);
                                        if (letter == 'z') {
                                                char *p;
                                                for (p = dest + width - 1;
                                                (p >= (char *)dest) && (*p == ' '); p--)
                                                        *p = 0;
                                        }
                                }
                                assigned++;
                        }
                        databuf += width;
                        field_name[0] = 0;
                        suppress = 0;
                        break;

                case 's':       /* Seek */
                        shift = 0;
                        fmt++;
                        if (*fmt == '+') {
                                plus = 1;
                                fmt++;
                        } else
                                plus = 0;

                        if (tolower((unsigned char)*fmt) == 'v') {
                                /* You can't suppress a seek value.  You also
                                 * can't have a variable seek when you are using
                                 * "arg_put".
                                 */
                                width = (arg_put) ? 0 : va_arg(ap, int);
                                fmt++;
                        } else
                                width = strtol(fmt, &fmt, 10);

                        if (plus)
                                databuf += width;       /* Relative seek */
                        else
                                databuf = base + width; /* Absolute seek */

                        break;

                case 0:
                        done = 1;
                        break;

                default:
                        fprintf(stderr, "Unknown letter in format: %c\n", letter);
                        fmt++;
                }
        }

        return assigned;
}

int
scsireq_decode_visit(scsireq_t *scsireq, char *fmt,
    void (*arg_put)(void *, int , void *, int, char *), void *puthook)
{
        va_list ap;
        int ret;

        ret = do_buff_decode(scsireq->databuf, (size_t)scsireq->datalen,
            arg_put, puthook, fmt, ap);
        va_end (ap);
        return (ret);
}

int
scsireq_buff_decode_visit(u_char *buff, size_t len, char *fmt,
    void (*arg_put)(void *, int, void *, int, char *), void *puthook)
{
        va_list ap;

        /* XXX */
        return do_buff_decode(buff, len, arg_put, puthook, fmt, ap);
}

/* next_field: Return the next field in a command specifier.  This
 * builds up a SCSI command using this trivial grammar:
 *
 * fields : field fields
 *        ;
 *
 * field : value
 *       | value ':' field_width
 *       ;
 *
 * field_width : digit
 *       | 'i' digit            // i2 = 2 byte integer, i3 = 3 byte integer etc.
 *       ;
 *
 * value : HEX_NUMBER
 *       | 'v'                          // For indirection.
 *       ;
 *
 * Notes:
 *  Bit fields are specified MSB first to match the SCSI spec.
 *
 * Examples:
 *  TUR: "0 0 0 0 0 0"
 *  WRITE BUFFER: "38 v:3 0:2 0:3 v v:i3 v:i3 0", mode, buffer_id, list_length
 *
 * The function returns the value:
 *  0: For reached end, with error_p set if an error was found
 *  1: For valid stuff setup
 *  2: For "v" was entered as the value (implies use varargs)
 *
 */
static int
next_field(char **pp, char *fmt, int *width_p, int *value_p, char *name,
    int n_name, int *error_p, int *suppress_p)
{
        char *p = *pp;

        int something = 0;

        enum { BETWEEN_FIELDS, START_FIELD, GET_FIELD, DONE } state;

        int value = 0;
        int field_size;         /* Default to byte field type... */
        int field_width;        /* 1 byte wide */
        int is_error = 0;
        int suppress = 0;

        field_size = 8;         /* Default to byte field type... */
        *fmt = 'i';
        field_width = 1;        /* 1 byte wide */
        if (name)
                *name = 0;

        state = BETWEEN_FIELDS;

        while (state != DONE)
                switch (state)
                {
                case BETWEEN_FIELDS:
                        if (*p == 0)
                                state = DONE;
                        else if (isspace((unsigned char)*p))
                                p++;
                        else if (*p == '#') {
                                while (*p && *p != '\n')
                                        p++;

                                if (p)
                                        p++;
                                } else if (*p == '{') {
                                        int i = 0;

                                        p++;

                                        while (*p && *p != '}') {
                                                if (name && i < n_name) {
                                                        name[i] = *p;
                                                        i++;
                                                }
                                                p++;
                                        }

                                        if (name && i < n_name)
                                                name[i] = 0;

                                        if (*p == '}')
                                                p++;
                                } else if (*p == '*') {
                                        p++;
                                        suppress = 1;
                                } else if (isxdigit((unsigned char)*p)) {
                                        something = 1;
                                        value = strtol(p, &p, 16);
                                        state = START_FIELD;
                                } else if (tolower((unsigned char)*p) == 'v') {
                                        p++;
                                        something = 2;
                                        value = *value_p;
                                        state = START_FIELD;
                                }
                                /* try to work without the 'v' */
                                else if (tolower((unsigned char)*p) == 'i') {
                                        something = 2;
                                        value = *value_p;
                                        p++;

                                        *fmt = 'i';
                                        field_size = 8;
                                        field_width = strtol(p, &p, 10);
                                        state = DONE;
                                } else if (tolower((unsigned char)*p) == 't') {
                                        /* XXX: B can't work: Sees the 'b'
                                         * as a hex digit in "isxdigit".
                                         * try "t" for bit field.
                                         */
                                        something = 2;
                                        value = *value_p;
                                        p++;

                                        *fmt = 'b';
                                        field_size = 1;
                                        field_width = strtol(p, &p, 10);
                                        state = DONE;
                                } else if (tolower((unsigned char)*p) == 's') { /* Seek */
                                        *fmt = 's';
                                        p++;
                                        if (tolower((unsigned char)*p) == 'v') {
                                                p++;
                                                something = 2;
                                                value = *value_p;
                                        } else {
                                                something = 1;
                                                value = strtol(p, &p, 0);
                                        }
                                        state = DONE;
                                } else {
                                        fprintf(stderr, "Invalid starting character: %c\n", *p);
                                        is_error = 1;
                                        state = DONE;
                                }
                        break;

                case START_FIELD:
                        if (*p == ':') {
                                p++;
                                field_size = 1;         /* Default to bits when specified */
                                state = GET_FIELD;
                        } else
                                state = DONE;
                        break;

                case GET_FIELD:
                        if (isdigit((unsigned char)*p)) {
                                *fmt = 'b';
                                field_size = 1;
                                field_width = strtol(p, &p, 10);
                                state = DONE;
                        } else if (*p == 'i') { /* Integral (bytes) */
                                p++;

                                *fmt = 'i';
                                field_size = 8;
                                field_width = strtol(p, &p, 10);
                                state = DONE;
                        } else if (*p == 'b') { /* Bits */
                                p++;

                                *fmt = 'b';
                                field_size = 1;
                                field_width = strtol(p, &p, 10);
                                state = DONE;
                        } else {
                                fprintf(stderr, "Invalid startfield %c (%02x)\n",
                                    *p, *p);
                                is_error = 1;
                                state = DONE;
                        }
                        break;

                case DONE:
                        break;
                }

        if (is_error) {
                *error_p = 1;
                return 0;
        }

        *error_p = 0;
        *pp = p;
        *width_p = field_width * field_size;
        *value_p = value;
        *suppress_p = suppress;

        return something;
}

static int
do_encode(u_char *buff, size_t vec_max, size_t *used,
    int (*arg_get)(void *, char *),
    void *gethook, char *fmt, va_list ap)
{
        int ind;
        int shift;
        u_char val;
        int ret;
        int width, value, error, suppress;
        char c;
        int encoded = 0;
        char field_name[80];

        ind = 0;
        shift = 0;
        val = 0;

        while ((ret = next_field(&fmt, &c, &width, &value, field_name,
            sizeof(field_name), &error, &suppress)))
        {
                encoded++;

                if (ret == 2) {
                        if (suppress)
                                value = 0;
                        else
                                value = arg_get ? (*arg_get)(gethook, field_name) : va_arg(ap, int);
                }

#if 0
                printf(
                    "do_encode: ret %d fmt %c width %d value %d name \"%s\""
                    "error %d suppress %d\n",
                    ret, c, width, value, field_name, error, suppress);
#endif

                if (c == 's')   /* Absolute seek */
                {
                        ind = value;
                        continue;
                }

                if (width < 8)  /* A width of < 8 is a bit field. */
                {

                        /* This is a bit field.  We start with the high bits
                         * so it reads the same as the SCSI spec.
                         */

                        shift += width;

                        val |= (value << (8 - shift));

                        if (shift == 8) {
                                if (ind < vec_max) {
                                        buff[ind++] = val;
                                        val = 0;
                                }
                                shift = 0;
                        }
                } else {
                        if (shift) {
                                if (ind < vec_max) {
                                        buff[ind++] = val;
                                        val = 0;
                                }
                                shift = 0;
                        }
                        switch (width)
                        {
                        case 8:         /* 1 byte integer */
                                if (ind < vec_max)
                                        buff[ind++] = value;
                                break;

                        case 16:        /* 2 byte integer */
                                if (ind < vec_max - 2 + 1) {
                                        buff[ind++] = value >> 8;
                                        buff[ind++] = value;
                                }
                                break;

                        case 24:        /* 3 byte integer */
                                if (ind < vec_max - 3 + 1) {
                                        buff[ind++] = value >> 16;
                                        buff[ind++] = value >> 8;
                                        buff[ind++] = value;
                                }
                                break;

                        case 32:        /* 4 byte integer */
                                if (ind < vec_max - 4 + 1) {
                                        buff[ind++] = value >> 24;
                                        buff[ind++] = value >> 16;
                                        buff[ind++] = value >> 8;
                                        buff[ind++] = value;
                                }
                                break;

                        default:
                                fprintf(stderr, "do_encode: Illegal width\n");
                                break;
                        }
                }
        }

        /* Flush out any remaining bits */
        if (shift && ind < vec_max) {
                buff[ind++] = val;
                val = 0;
        }


        if (used)
                *used = ind;

        if (error)
                return -1;

        return encoded;
}

scsireq_t *
scsireq_build(scsireq_t *scsireq, u_long datalen, caddr_t databuf,
    u_long flags, char *cmd_spec, ...)
{
        size_t cmdlen;
        va_list ap;

        if (scsireq == 0)
                return 0;

        scsireq_reset(scsireq);

        if (databuf) {
                scsireq->databuf = databuf;
                scsireq->datalen = datalen;
                scsireq->flags = flags;
        }
        else if (datalen) {
                /* XXX: Good way to get a memory leak.  Perhaps this should be
                 * removed.
                 */
                if ( (scsireq->databuf = malloc(datalen)) == NULL)
                        return 0;

                scsireq->datalen = datalen;
                scsireq->flags = flags;
        }

        va_start(ap, cmd_spec);

        if (do_encode(scsireq->cmd, CMDBUFLEN, &cmdlen, 0, 0, cmd_spec, ap) == -1)
                return 0;
        va_end (ap);

        scsireq->cmdlen = cmdlen;
        return scsireq;
}

scsireq_t
*scsireq_build_visit(scsireq_t *scsireq, u_long datalen, caddr_t databuf,
    u_long flags, char *cmd_spec,
    int (*arg_get)(void *hook, char *field_name), void *gethook)
{
        size_t cmdlen;
        va_list ap;

        if (scsireq == 0)
                return 0;

        scsireq_reset(scsireq);

        if (databuf) {
                scsireq->databuf = databuf;
                scsireq->datalen = datalen;
                scsireq->flags = flags;
        } else if (datalen) {
                /* XXX: Good way to get a memory leak.  Perhaps this should be
                 * removed.
                 */
                if ( (scsireq->databuf = malloc(datalen)) == NULL)
                        return 0;

                scsireq->datalen = datalen;
                scsireq->flags = flags;
        }

        if (do_encode(scsireq->cmd, CMDBUFLEN, &cmdlen, arg_get, gethook,
            cmd_spec, ap) == -1)
                return 0;

        scsireq->cmdlen = cmdlen;

        return scsireq;
}

int
scsireq_buff_encode_visit(u_char *buff, size_t len, char *fmt,
        int (*arg_get)(void *hook, char *field_name), void *gethook)
{
        va_list ap;
        return do_encode(buff, len, 0, arg_get, gethook, fmt, ap);
}

int
scsireq_encode_visit(scsireq_t *scsireq, char *fmt,
    int (*arg_get)(void *hook, char *field_name), void *gethook)
{
        va_list ap;
        return do_encode(scsireq->databuf, scsireq->datalen, 0,
            arg_get, gethook, fmt, ap);
}

FILE *
scsi_debug_output(char *s)
{
        if (s == 0)
                behave.db_f = 0;
        else {
                behave.db_f = fopen(s, "w");

                if (behave.db_f == 0)
                        behave.db_f = stderr;
        }

        return behave.db_f;
}

#define SCSI_TRUNCATE -1

typedef struct scsi_assoc {
        int code;
        char *text;
} scsi_assoc_t;

static scsi_assoc_t retsts[] =
{
        { SCCMD_OK, "No error" },
        { SCCMD_TIMEOUT, "Command Timeout" },
        { SCCMD_BUSY, "Busy" },
        { SCCMD_SENSE, "Sense Returned" },
        { SCCMD_UNKNOWN, "Unknown return status" },

        { 0, 0 }
};

static char *
scsi_assoc_text(int code, scsi_assoc_t *tab)
{
        while (tab->text) {
                if (tab->code == code)
                        return tab->text;

                tab++;
        }

        return "Unknown code";
}

void
scsi_dump(FILE *f, char *text, u_char *p, int req, int got, int dump_print)
{
        int i;
        int trunc = 0;

        if (f == 0 || req == 0)
                return;

        fprintf(f, "%s (%d of %d):\n", text, got, req);

        if (behave.db_trunc != -1 && got > behave.db_trunc) {
                trunc = 1;
                got = behave.db_trunc;
        }

        for (i = 0; i < got; i++) {
                fprintf(f, "%02x", p[i]);

                putc(' ', f);

                if ((i % 16) == 15 || i == got - 1) {
                        int j;
                        if (dump_print) {
                                fprintf(f, " # ");
                                for (j = i - 15; j <= i; j++)
                                        putc((isprint(p[j]) ? p[j] : '.'), f);

                                putc('\n', f);
                        } else
                                putc('\n', f);
                }
        }

        fprintf(f, "%s", (trunc) ? "(truncated)...\n" : "\n");
}

/* XXX: sense_7x_dump and scsi_sense dump was just sort of
 * grabbed out of the old ds
 * library and not really merged in carefully.  It should use the
 * new buffer decoding stuff.
 */

/* Get unsigned long.
 */
static u_long
g_u_long(u_char *s)
{
        return (s[0] << 24) | (s[1] << 16) | (s[2] << 8) | s[3];
}

/* In the old software you could patch in a special error table:
 */
static scsi_assoc_t *error_table = 0;

static void
sense_7x_dump(FILE *f, scsireq_t *scsireq)
{
        int code;
        u_char *s = (u_char *)scsireq->sense;
        int valid = (*s) & 0x80;
        u_long val;

        static scsi_assoc_t sense[] = {
                { 0, "No sense" },
                { 1, "Recovered error" },
                { 2, "Not Ready" },
                { 3, "Medium error" },
                { 4, "Hardware error" },
                { 5, "Illegal request" },
                { 6, "Unit attention" },
                { 7, "Data protect" },
                { 8, "Blank check" },
                { 9, "Vendor specific" },
                { 0xa, "Copy aborted" },
                { 0xb, "Aborted Command" },
                { 0xc, "Equal" },
                { 0xd, "Volume overflow" },
                { 0xe, "Miscompare" },
                { 0, 0 },
        };

        static scsi_assoc_t code_tab[] = {
                {0x70, "current errors"},
                {0x71, "deferred errors"},
        };

        fprintf(f, "Error code is \"%s\"\n", scsi_assoc_text(s[0]&0x7F, code_tab));
        fprintf(f, "Segment number is %02x\n", s[1]);

        if (s[2] & 0x20)
                fprintf(f, "Incorrect Length Indicator is set.\n");

        fprintf(f, "Sense key is \"%s\"\n", scsi_assoc_text(s[2] & 0x7, sense));

        val = g_u_long(s + 3);
        fprintf(f, "The Information field is%s %08lx (%ld).\n",
            valid ? "" : " not valid but contains", (long)val, (long)val);

        val = g_u_long(s + 8);
        fprintf(f, "The Command Specific Information field is %08lx (%ld).\n",
            (long)val, (long)val);

        fprintf(f, "Additional sense code: %02x\n", s[12]);
        fprintf(f, "Additional sense code qualifier: %02x\n", s[13]);

        code = (s[12] << 8) | s[13];

        if (error_table)
                fprintf(f, "%s\n", scsi_assoc_text(code, error_table));

        if (s[15] & 0x80) {
                if ((s[2] & 0x7) == 0x05)       /* Illegal request */
                {
                        int byte;
                        u_char value, bit;
                        int bad_par = ((s[15] & 0x40) == 0);
                        fprintf(f, "Illegal value in the %s.\n",
                            (bad_par ? "parameter list" : "command descriptor block"));
                        byte = ((s[16] << 8) | s[17]);
                        value = bad_par ? (u_char)scsireq->databuf[byte] : (u_char)scsireq->cmd[byte];
                        bit = s[15] & 0x7;
                        if (s[15] & 0x08)
                                fprintf(f, "Bit %d of byte %d (value %02x) is illegal.\n",
                                    bit, byte, value);
                        else
                                fprintf(f, "Byte %d (value %02x) is illegal.\n", byte, value);
                } else  {
                        fprintf(f, "Sense Key Specific (valid but not illegal request):\n");
                        fprintf(f, "%02x %02x %02x\n", s[15] & 0x7f, s[16], s[17]);
                }
        }
}

/* scsi_sense_dump: Dump the sense portion of the scsireq structure.
 */
static void
scsi_sense_dump(FILE *f, scsireq_t *scsireq)
{
        u_char *s = (u_char *)scsireq->sense;
        int code = (*s) & 0x7f;

        if (scsireq->senselen_used == 0) {
                fprintf(f, "No sense sent.\n");
                return;
        }

#if 0
        if (!valid)
                fprintf(f, "The sense data is not valid.\n");
#endif

        switch (code) {
        case 0x70:
        case 0x71:
                sense_7x_dump(f, scsireq);
                break;

        default:
                fprintf(f, "No sense dump for error code %02x.\n", code);
        }
        scsi_dump(f, "sense", s, scsireq->senselen, scsireq->senselen_used, 0);
}

static void
scsi_retsts_dump(FILE *f, scsireq_t *scsireq)
{
        if (scsireq->retsts == 0)
                return;

        fprintf(f, "return status %d (%s)",
            scsireq->retsts, scsi_assoc_text(scsireq->retsts, retsts));

        switch (scsireq->retsts) {
        case SCCMD_TIMEOUT:
                fprintf(f, " after %ld ms", scsireq->timeout);
                break;

        default:
                break;
        }
}

int
scsi_debug(FILE *f, int ret, scsireq_t *scsireq)
{
        char *d;
        if (f == 0)
                return 0;

        fprintf(f, "SCIOCCOMMAND ioctl");

        if (ret == 0)
                fprintf(f, ": Command accepted.");
        else {
                if (ret != -1)
                        fprintf(f, ", return value %d?", ret);

                if (errno) {
                        fprintf(f, ": %s", strerror(errno));
                        errno = 0;
                }
        }

        fputc('\n', f);

        if (ret == 0 && (scsireq->status || scsireq->retsts || behave.db_level))
        {
                scsi_retsts_dump(f, scsireq);

                if (scsireq->status)
                        fprintf(f, " host adapter status %d\n", scsireq->status);

                if (scsireq->flags & SCCMD_READ)
                        d = "Data in";
                else if (scsireq->flags & SCCMD_WRITE)
                        d = "Data out";
                else
                        d = "No data transfer?";

                if (scsireq->cmdlen == 0)
                        fprintf(f, "Zero length command????\n");

                scsi_dump(f, "Command out",
                    (u_char *)scsireq->cmd, scsireq->cmdlen, scsireq->cmdlen, 0);
                scsi_dump(f, d,
                    (u_char *)scsireq->databuf, scsireq->datalen,
                scsireq->datalen_used, 1);
                scsi_sense_dump(f, scsireq);
        }

        fflush(f);

        return ret;
}

static char *debug_output;

int
scsi_open(const char *path, int flags)
{
        int fd = open(path, flags);

        if (fd != -1) {
                char *p;
                debug_output = getenv("SU_DEBUG_OUTPUT");
                (void)scsi_debug_output(debug_output);

                if ((p = getenv("SU_DEBUG_LEVEL")))
                        sscanf(p, "%d", &behave.db_level);

                if ((p = getenv("SU_DEBUG_TRUNCATE")))
                        sscanf(p, "%d", &behave.db_trunc);
                else
                        behave.db_trunc = SCSI_TRUNCATE;
        }

        return fd;
}

int
scsireq_enter(int fid, scsireq_t *scsireq)
{
        int ret;

        ret = ioctl(fid, SCIOCCOMMAND, (void *)scsireq);

        if (behave.db_f)
                scsi_debug(behave.db_f, ret, scsireq);

        return ret;
}