source: MondoRescue/branches/3.2/mindi-busybox/miscutils/mt.c@ 3232

/* vi: set sw=4 ts=4: */
/*
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

//usage:#define mt_trivial_usage
//usage:       "[-f device] opcode value"
//usage:#define mt_full_usage "\n\n"
//usage:       "Control magnetic tape drive operation\n"
//usage:       "\n"
//usage:       "Available Opcodes:\n"
//usage:       "\n"
//usage:       "bsf bsfm bsr bss datacompression drvbuffer eof eom erase\n"
//usage:       "fsf fsfm fsr fss load lock mkpart nop offline ras1 ras2\n"
//usage:       "ras3 reset retension rewind rewoffline seek setblk setdensity\n"
//usage:       "setpart tell unload unlock weof wset"

#include "libbb.h"
#include <sys/mtio.h>

/* missing: eod/seod, stoptions, stwrthreshold, densities */
static const short opcode_value[] = {
    MTBSF,
    MTBSFM,
    MTBSR,
    MTBSS,
    MTCOMPRESSION,
    MTEOM,
    MTERASE,
    MTFSF,
    MTFSFM,
    MTFSR,
    MTFSS,
    MTLOAD,
    MTLOCK,
    MTMKPART,
    MTNOP,
    MTOFFL,
    MTOFFL,
    MTRAS1,
    MTRAS2,
    MTRAS3,
    MTRESET,
    MTRETEN,
    MTREW,
    MTSEEK,
    MTSETBLK,
    MTSETDENSITY,
    MTSETDRVBUFFER,
    MTSETPART,
    MTTELL,
    MTWSM,
    MTUNLOAD,
    MTUNLOCK,
    MTWEOF,
    MTWEOF
};

static const char opcode_name[] ALIGN1 =
    "bsf"             "\0"
    "bsfm"            "\0"
    "bsr"             "\0"
    "bss"             "\0"
    "datacompression" "\0"
    "eom"             "\0"
    "erase"           "\0"
    "fsf"             "\0"
    "fsfm"            "\0"
    "fsr"             "\0"
    "fss"             "\0"
    "load"            "\0"
    "lock"            "\0"
    "mkpart"          "\0"
    "nop"             "\0"
    "offline"         "\0"
    "rewoffline"      "\0"
    "ras1"            "\0"
    "ras2"            "\0"
    "ras3"            "\0"
    "reset"           "\0"
    "retension"       "\0"
    "rewind"          "\0"
    "seek"            "\0"
    "setblk"          "\0"
    "setdensity"      "\0"
    "drvbuffer"       "\0"
    "setpart"         "\0"
    "tell"            "\0"
    "wset"            "\0"
    "unload"          "\0"
    "unlock"          "\0"
    "eof"             "\0"
    "weof"            "\0";

int mt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mt_main(int argc UNUSED_PARAM, char **argv)
{
    const char *file = "/dev/tape";
    struct mtop op;
    struct mtpos position;
    int fd, mode, idx;

    if (!argv[1]) {
        bb_show_usage();
    }

    if (strcmp(argv[1], "-f") == 0) {
        if (!argv[2] || !argv[3])
            bb_show_usage();
        file = argv[2];
        argv += 2;
    }

    idx = index_in_strings(opcode_name, argv[1]);

    if (idx < 0)
        bb_error_msg_and_die("unrecognized opcode %s", argv[1]);

    op.mt_op = opcode_value[idx];
    if (argv[2])
        op.mt_count = xatoi_positive(argv[2]);
    else
        op.mt_count = 1;  /* One, not zero, right? */

    switch (opcode_value[idx]) {
        case MTWEOF:
        case MTERASE:
        case MTWSM:
        case MTSETDRVBUFFER:
            mode = O_WRONLY;
            break;

        default:
            mode = O_RDONLY;
            break;
    }

    fd = xopen(file, mode);

    switch (opcode_value[idx]) {
        case MTTELL:
            ioctl_or_perror_and_die(fd, MTIOCPOS, &position, "%s", file);
            printf("At block %d\n", (int) position.mt_blkno);
            break;

        default:
            ioctl_or_perror_and_die(fd, MTIOCTOP, &op, "%s", file);
            break;
    }

    return EXIT_SUCCESS;
}