/*      $OpenBSD: args.c,v 1.31 2019/02/16 10:54:00 bluhm Exp $ */
/*      $NetBSD: args.c,v 1.7 1996/03/01 01:18:58 jtc Exp $     */

/*-
 * Copyright (c) 1991, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Keith Muller of the University of California, San Diego and Lance
 * Visser of Convex Computer Corporation.
 *
 * 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. Neither the name of the University 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 THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS 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.
 */

#include <sys/types.h>
#include <sys/time.h>

#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "dd.h"
#include "extern.h"

static int      c_arg(const void *, const void *);
static void     f_bs(char *);
static void     f_cbs(char *);
static void     f_conv(char *);
static void     f_count(char *);
static void     f_files(char *);
static void     f_ibs(char *);
static void     f_if(char *);
static void     f_obs(char *);
static void     f_of(char *);
static void     f_seek(char *);
static void     f_skip(char *);
static void     f_status(char *);
static size_t   get_bsz(char *);
static off_t    get_off(char *);

static const struct arg {
        const char *name;
        void (*f)(char *);
        u_int set, noset;
} args[] = {
        { "bs",         f_bs,           C_BS,    C_BS|C_IBS|C_OBS|C_OSYNC },
        { "cbs",        f_cbs,          C_CBS,   C_CBS },
        { "conv",       f_conv,         0,       0 },
        { "count",      f_count,        C_COUNT, C_COUNT },
        { "files",      f_files,        C_FILES, C_FILES },
        { "ibs",        f_ibs,          C_IBS,   C_BS|C_IBS },
        { "if",         f_if,           C_IF,    C_IF },
        { "obs",        f_obs,          C_OBS,   C_BS|C_OBS },
        { "of",         f_of,           C_OF,    C_OF },
        { "seek",       f_seek,         C_SEEK,  C_SEEK },
        { "skip",       f_skip,         C_SKIP,  C_SKIP },
        { "status",     f_status,       C_STATUS,C_STATUS },
};

static char *oper;

/*
 * args -- parse JCL syntax of dd.
 */
void
jcl(char **argv)
{
        struct arg *ap, tmp;
        char *arg;

        in.dbsz = out.dbsz = 512;

        while (*++argv != NULL) {
                if ((oper = strdup(*argv)) == NULL)
                        err(1, NULL);
                if ((arg = strchr(oper, '=')) == NULL)
                        errx(1, "unknown operand %s", oper);
                *arg++ = '\0';
                if (!*arg)
                        errx(1, "no value specified for %s", oper);
                tmp.name = oper;
                if (!(ap = (struct arg *)bsearch(&tmp, args,
                    sizeof(args)/sizeof(struct arg), sizeof(struct arg),
                    c_arg)))
                        errx(1, "unknown operand %s", tmp.name);
                if (ddflags & ap->noset)
                        errx(1, "%s: illegal argument combination or already set",
                            tmp.name);
                ddflags |= ap->set;
                ap->f(arg);
                free(oper);
        }

        /* Final sanity checks. */

        if (ddflags & C_BS) {
                /*
                 * Bs is turned off by any conversion -- we assume the user
                 * just wanted to set both the input and output block sizes
                 * and didn't want the bs semantics, so we don't warn.
                 */
                if (ddflags & (C_BLOCK|C_LCASE|C_SWAB|C_UCASE|C_UNBLOCK))
                        ddflags &= ~C_BS;

                /* Bs supersedes ibs and obs. */
                if (ddflags & C_BS && ddflags & (C_IBS|C_OBS))
                        warnx("bs supersedes ibs and obs");
        }

        /*
         * Ascii/ebcdic and cbs implies block/unblock.
         * Block/unblock requires cbs and vice-versa.
         */
        if (ddflags & (C_BLOCK|C_UNBLOCK)) {
                if (!(ddflags & C_CBS))
                        errx(1, "record operations require cbs");
                if (cbsz == 0)
                        errx(1, "cbs cannot be zero");
                cfunc = ddflags & C_BLOCK ? block : unblock;
        } else if (ddflags & C_CBS) {
                if (ddflags & (C_ASCII|C_EBCDIC)) {
                        if (ddflags & C_ASCII) {
                                ddflags |= C_UNBLOCK;
                                cfunc = unblock;
                        } else {
                                ddflags |= C_BLOCK;
                                cfunc = block;
                        }
                } else
                        errx(1, "cbs meaningless if not doing record operations");
                if (cbsz == 0)
                        errx(1, "cbs cannot be zero");
        } else
                cfunc = def;

        if (in.dbsz == 0 || out.dbsz == 0)
                errx(1, "buffer sizes cannot be zero");

        /*
         * Read and write take size_t's as arguments.  Lseek, however,
         * takes an off_t.
         */
        if (cbsz > SSIZE_MAX || in.dbsz > SSIZE_MAX || out.dbsz > SSIZE_MAX)
                errx(1, "buffer sizes cannot be greater than %zd",
                    (ssize_t)SSIZE_MAX);
        if (in.offset > LLONG_MAX / in.dbsz || out.offset > LLONG_MAX / out.dbsz)
                errx(1, "seek offsets cannot be larger than %lld", LLONG_MAX);
}

static int
c_arg(const void *a, const void *b)
{

        return (strcmp(((struct arg *)a)->name, ((struct arg *)b)->name));
}

static void
f_bs(char *arg)
{

        in.dbsz = out.dbsz = get_bsz(arg);
}

static void
f_cbs(char *arg)
{

        cbsz = get_bsz(arg);
}

static void
f_count(char *arg)
{

        if ((cpy_cnt = get_bsz(arg)) == 0)
                cpy_cnt = (size_t)-1;
}

static void
f_files(char *arg)
{

        files_cnt = get_bsz(arg);
}

static void
f_ibs(char *arg)
{

        if (!(ddflags & C_BS))
                in.dbsz = get_bsz(arg);
}

static void
f_if(char *arg)
{
        if ((in.name = strdup(arg)) == NULL)
                err(1, NULL);
}

static void
f_obs(char *arg)
{

        if (!(ddflags & C_BS))
                out.dbsz = get_bsz(arg);
}

static void
f_of(char *arg)
{
        if ((out.name = strdup(arg)) == NULL)
                err(1, NULL);
}

static void
f_seek(char *arg)
{

        out.offset = get_off(arg);
}

static void
f_skip(char *arg)
{

        in.offset = get_off(arg);
}

static void
f_status(char *arg)
{

        if (strcmp(arg, "none") == 0)
                ddflags |= C_NOINFO;
        else if (strcmp(arg, "noxfer") == 0)
                ddflags |= C_NOXFER;
        else
                errx(1, "unknown status %s", arg);
}


static const struct conv {
        const char *name;
        u_int set, noset;
        const u_char *ctab;
} clist[] = {
#ifndef NO_CONV
        { "ascii",      C_ASCII,        C_EBCDIC,       e2a_POSIX },
        { "block",      C_BLOCK,        C_UNBLOCK,      NULL },
        { "ebcdic",     C_EBCDIC,       C_ASCII,        a2e_POSIX },
        { "fsync",      C_FSYNC,        0,              NULL },
        { "ibm",        C_EBCDIC,       C_ASCII,        a2ibm_POSIX },
        { "lcase",      C_LCASE,        C_UCASE,        NULL },
        { "osync",      C_OSYNC,        C_BS,           NULL },
        { "swab",       C_SWAB,         0,              NULL },
        { "sync",       C_SYNC,         0,              NULL },
        { "ucase",      C_UCASE,        C_LCASE,        NULL },
        { "unblock",    C_UNBLOCK,      C_BLOCK,        NULL },
#endif
        { "noerror",    C_NOERROR,      0,              NULL },
        { "notrunc",    C_NOTRUNC,      0,              NULL },
        { NULL,         0,              0,              NULL }
};

static void
f_conv(char *arg)
{
        const struct conv *cp;
        const char *name;

        while (arg != NULL) {
                name = strsep(&arg, ",");
                for (cp = &clist[0]; cp->name; cp++)
                        if (strcmp(name, cp->name) == 0)
                                break;
                if (!cp->name)
                        errx(1, "unknown conversion %s", name);
                if (ddflags & cp->noset)
                        errx(1, "%s: illegal conversion combination", name);
                ddflags |= cp->set;
                if (cp->ctab)
                        ctab = cp->ctab;
        }
}

/*
 * Convert an expression of the following forms to a size_t
 *      1) A positive decimal number, optionally followed by
 *              b - multiply by 512.
 *              k, m or g - multiply by 1024 each.
 *              w - multiply by sizeof int
 *      2) Two or more of the above, separated by x
 *         (or * for backwards compatibility), specifying
 *         the product of the indicated values.
 */
static size_t
get_bsz(char *val)
{
        size_t num, t;
        char *expr;

        if (strchr(val, '-'))
                errx(1, "%s: illegal numeric value", oper);

        errno = 0;
        num = strtoul(val, &expr, 0);
        if (num == ULONG_MAX && errno == ERANGE)        /* Overflow. */
                err(1, "%s", oper);
        if (expr == val)                        /* No digits. */
                errx(1, "%s: illegal numeric value", oper);

        switch(*expr) {
        case 'b':
                t = num;
                num *= 512;
                if (t > num)
                        goto erange;
                ++expr;
                break;
        case 'g':
        case 'G':
                t = num;
                num *= 1024;
                if (t > num)
                        goto erange;
                /* fallthrough */
        case 'm':
        case 'M':
                t = num;
                num *= 1024;
                if (t > num)
                        goto erange;
                /* fallthrough */
        case 'k':
        case 'K':
                t = num;
                num *= 1024;
                if (t > num)
                        goto erange;
                ++expr;
                break;
        case 'w':
                t = num;
                num *= sizeof(int);
                if (t > num)
                        goto erange;
                ++expr;
                break;
        }

        switch(*expr) {
                case '\0':
                        break;
                case '*':                       /* Backward compatible. */
                case 'x':
                        t = num;
                        num *= get_bsz(expr + 1);
                        if (t > num)
                                goto erange;
                        break;
                default:
                        errx(1, "%s: illegal numeric value", oper);
        }
        return (num);
erange:
        errc(1, ERANGE, "%s", oper);
}

/*
 * Convert an expression of the following forms to an off_t
 *      1) A positive decimal number, optionally followed by
 *              b - multiply by 512.
 *              k, m or g - multiply by 1024 each.
 *              w - multiply by sizeof int
 *      2) Two or more of the above, separated by x
 *         (or * for backwards compatibility), specifying
 *         the product of the indicated values.
 */
static off_t
get_off(char *val)
{
        off_t num, t;
        char *expr;

        errno = 0;
        num = strtoll(val, &expr, 0);
        if (num == LLONG_MAX && errno == ERANGE)        /* Overflow. */
                err(1, "%s", oper);
        if (expr == val)                        /* No digits. */
                errx(1, "%s: illegal numeric value", oper);

        switch(*expr) {
        case 'b':
                t = num;
                num *= 512;
                if (t > num)
                        goto erange;
                ++expr;
                break;
        case 'g':
        case 'G':
                t = num;
                num *= 1024;
                if (t > num)
                        goto erange;
                /* fallthrough */
        case 'm':
        case 'M':
                t = num;
                num *= 1024;
                if (t > num)
                        goto erange;
                /* fallthrough */
        case 'k':
        case 'K':
                t = num;
                num *= 1024;
                if (t > num)
                        goto erange;
                ++expr;
                break;
        case 'w':
                t = num;
                num *= sizeof(int);
                if (t > num)
                        goto erange;
                ++expr;
                break;
        }

        switch(*expr) {
                case '\0':
                        break;
                case '*':                       /* Backward compatible. */
                case 'x':
                        t = num;
                        num *= get_off(expr + 1);
                        if (t > num)
                                goto erange;
                        break;
                default:
                        errx(1, "%s: illegal numeric value", oper);
        }
        return (num);
erange:
        errc(1, ERANGE, "%s", oper);
}