bin/dd/args.c

   1 /*-
   2  * Copyright (c) 1991, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Keith Muller of the University of California, San Diego and Lance
   7  * Visser of Convex Computer Corporation.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed by the University of
  20  *      California, Berkeley and its contributors.
  21  * 4. Neither the name of the University nor the names of its contributors
  22  *    may be used to endorse or promote products derived from this software
  23  *    without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  35  * SUCH DAMAGE.
  36  *
  37  * @(#)args.c   8.3 (Berkeley) 4/2/94
  38  * $FreeBSD: src/bin/dd/args.c,v 1.25.2.2 2001/01/23 14:20:03 asmodai Exp $
  39  * $DragonFly: src/bin/dd/args.c,v 1.5 2004/03/19 18:17:46 cpressey Exp $
  40  */
  41
  42 #include <sys/types.h>
  43
  44 #include <err.h>
  45 #include <errno.h>
  46 #include <limits.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49
  50 #include "dd.h"
  51 #include "extern.h"
  52
  53 static int      c_arg (const void *, const void *);
  54 static int      c_conv (const void *, const void *);
  55 static void     f_bs (char *);
  56 static void     f_cbs (char *);
  57 static void     f_conv (char *);
  58 static void     f_count (char *);
  59 static void     f_files (char *);
  60 static void     f_ibs (char *);
  61 static void     f_if (char *);
  62 static void     f_obs(char *);
  63 static void     f_of (char *);
  64 static void     f_seek (char *);
  65 static void     f_skip (char *);
  66 static quad_t   get_num (char *);
  67 static off_t    get_offset (char *);
  68
  69 static const struct arg {
  70         const char *name;
  71         void (*f) (char *);
  72         u_int set, noset;
  73 } args[] = {
  74         { "bs",         f_bs,           C_BS,    C_BS|C_IBS|C_OBS|C_OSYNC },
  75         { "cbs",        f_cbs,          C_CBS,   C_CBS },
  76         { "conv",       f_conv,         0,       0 },
  77         { "count",      f_count,        C_COUNT, C_COUNT },
  78         { "files",      f_files,        C_FILES, C_FILES },
  79         { "ibs",        f_ibs,          C_IBS,   C_BS|C_IBS },
  80         { "if",         f_if,           C_IF,    C_IF },
  81         { "iseek",      f_skip,         C_SKIP,  C_SKIP },
  82         { "obs",        f_obs,          C_OBS,   C_BS|C_OBS },
  83         { "of",         f_of,           C_OF,    C_OF },
  84         { "oseek",      f_seek,         C_SEEK,  C_SEEK },
  85         { "seek",       f_seek,         C_SEEK,  C_SEEK },
  86         { "skip",       f_skip,         C_SKIP,  C_SKIP },
  87 };
  88
  89 static char *oper;
  90
  91 /*
  92  * args -- parse JCL syntax of dd.
  93  */
  94 void
  95 jcl(char **argv)
  96 {
  97         struct arg *ap, tmp;
  98         char *arg;
  99
 100         in.dbsz = out.dbsz = 512;
 101
 102         while ((oper = *++argv) != NULL) {
 103                 if ((oper = strdup(oper)) == NULL)
 104                         errx(1, "unable to allocate space for the argument \"%s\"", *argv);
 105                 if ((arg = strchr(oper, '=')) == NULL)
 106                         errx(1, "unknown operand %s", oper);
 107                 *arg++ = '\0';
 108                 if (!*arg)
 109                         errx(1, "no value specified for %s", oper);
 110                 tmp.name = oper;
 111                 if (!(ap = (struct arg *)bsearch(&tmp, args,
 112                     sizeof(args)/sizeof(struct arg), sizeof(struct arg),
 113                     c_arg)))
 114                         errx(1, "unknown operand %s", tmp.name);
 115                 if (ddflags & ap->noset)
 116                         errx(1, "%s: illegal argument combination or already set",
 117                             tmp.name);
 118                 ddflags |= ap->set;
 119                 ap->f(arg);
 120         }
 121
 122         /* Final sanity checks. */
 123
 124         if (ddflags & C_BS) {
 125                 /*
 126                  * Bs is turned off by any conversion -- we assume the user
 127                  * just wanted to set both the input and output block sizes
 128                  * and didn't want the bs semantics, so we don't warn.
 129                  */
 130                 if (ddflags & (C_BLOCK | C_LCASE | C_SWAB | C_UCASE |
 131                     C_UNBLOCK))
 132                         ddflags &= ~C_BS;
 133
 134                 /* Bs supersedes ibs and obs. */
 135                 if (ddflags & C_BS && ddflags & (C_IBS | C_OBS))
 136                         warnx("bs supersedes ibs and obs");
 137         }
 138
 139         /*
 140          * Ascii/ebcdic and cbs implies block/unblock.
 141          * Block/unblock requires cbs and vice-versa.
 142          */
 143         if (ddflags & (C_BLOCK | C_UNBLOCK)) {
 144                 if (!(ddflags & C_CBS))
 145                         errx(1, "record operations require cbs");
 146                 if (cbsz == 0)
 147                         errx(1, "cbs cannot be zero");
 148                 cfunc = ddflags & C_BLOCK ? block : unblock;
 149         } else if (ddflags & C_CBS) {
 150                 if (ddflags & (C_ASCII | C_EBCDIC)) {
 151                         if (ddflags & C_ASCII) {
 152                                 ddflags |= C_UNBLOCK;
 153                                 cfunc = unblock;
 154                         } else {
 155                                 ddflags |= C_BLOCK;
 156                                 cfunc = block;
 157                         }
 158                 } else
 159                         errx(1, "cbs meaningless if not doing record operations");
 160         } else
 161                 cfunc = def;
 162
 163         /*
 164          * Bail out if the calculation of a file offset would overflow.
 165          */
 166         if (in.offset > QUAD_MAX / in.dbsz || out.offset > QUAD_MAX / out.dbsz)
 167                 errx(1, "seek offsets cannot be larger than %lld", QUAD_MAX);
 168 }
 169
 170 static int
 171 c_arg(const void *a, const void *b)
 172 {
 173
 174         return (strcmp(((const struct arg *)a)->name,
 175             ((const struct arg *)b)->name));
 176 }
 177
 178 static void
 179 f_bs(char *arg)
 180 {
 181         quad_t res;
 182
 183         res = get_num(arg);
 184         if (res < 1 || res > SSIZE_MAX)
 185                 errx(1, "bs must be between 1 and %d", SSIZE_MAX);
 186         in.dbsz = out.dbsz = (size_t)res;
 187 }
 188
 189 static void
 190 f_cbs(char *arg)
 191 {
 192         quad_t res;
 193
 194         res = get_num(arg);
 195         if (res < 1 || res > SSIZE_MAX)
 196                 errx(1, "cbs must be between 1 and %d", SSIZE_MAX);
 197         cbsz = (size_t)res;
 198 }
 199
 200 static void
 201 f_count(char *arg)
 202 {
 203
 204         cpy_cnt = get_num(arg);
 205         if (cpy_cnt < 0)
 206                 errx(1, "count cannot be negative");
 207         if (cpy_cnt == 0)
 208                 cpy_cnt = -1;
 209 }
 210
 211 static void
 212 f_files(char *arg)
 213 {
 214
 215         files_cnt = get_num(arg);
 216         if (files_cnt < 1)
 217                 errx(1, "files must be between 1 and %qd", QUAD_MAX);
 218 }
 219
 220 static void
 221 f_ibs(char *arg)
 222 {
 223         quad_t res;
 224
 225         if (!(ddflags & C_BS)) {
 226                 res = get_num(arg);
 227                 if (res < 1 || res > SSIZE_MAX)
 228                         errx(1, "ibs must be between 1 and %d", SSIZE_MAX);
 229                 in.dbsz = (size_t)res;
 230         }
 231 }
 232
 233 static void
 234 f_if(char *arg)
 235 {
 236
 237         in.name = arg;
 238 }
 239
 240 static void
 241 f_obs(char *arg)
 242 {
 243         quad_t res;
 244
 245         if (!(ddflags & C_BS)) {
 246                 res = get_num(arg);
 247                 if (res < 1 || res > SSIZE_MAX)
 248                         errx(1, "obs must be between 1 and %d", SSIZE_MAX);
 249                 out.dbsz = (size_t)res;
 250         }
 251 }
 252
 253 static void
 254 f_of(char *arg)
 255 {
 256
 257         out.name = arg;
 258 }
 259
 260 static void
 261 f_seek(char *arg)
 262 {
 263
 264         out.offset = get_offset(arg);
 265 }
 266
 267 static void
 268 f_skip(char *arg)
 269 {
 270
 271         in.offset = get_offset(arg);
 272 }
 273
 274 static const struct conv {
 275         const char *name;
 276         u_int set, noset;
 277         const u_char *ctab;
 278 } clist[] = {
 279         { "ascii",      C_ASCII,        C_EBCDIC,       e2a_POSIX },
 280         { "block",      C_BLOCK,        C_UNBLOCK,      NULL },
 281         { "ebcdic",     C_EBCDIC,       C_ASCII,        a2e_POSIX },
 282         { "ibm",        C_EBCDIC,       C_ASCII,        a2ibm_POSIX },
 283         { "lcase",      C_LCASE,        C_UCASE,        NULL },
 284         { "noerror",    C_NOERROR,      0,              NULL },
 285         { "notrunc",    C_NOTRUNC,      0,              NULL },
 286         { "oldascii",   C_ASCII,        C_EBCDIC,       e2a_32V },
 287         { "oldebcdic",  C_EBCDIC,       C_ASCII,        a2e_32V },
 288         { "oldibm",     C_EBCDIC,       C_ASCII,        a2ibm_32V },
 289         { "osync",      C_OSYNC,        C_BS,           NULL },
 290         { "sparse",     C_SPARSE,       0,              NULL },
 291         { "swab",       C_SWAB,         0,              NULL },
 292         { "sync",       C_SYNC,         0,              NULL },
 293         { "ucase",      C_UCASE,        C_LCASE,        NULL },
 294         { "unblock",    C_UNBLOCK,      C_BLOCK,        NULL },
 295 };
 296
 297 static void
 298 f_conv(char *arg)
 299 {
 300         struct conv *cp, tmp;
 301
 302         while (arg != NULL) {
 303                 tmp.name = strsep(&arg, ",");
 304                 cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
 305                     sizeof(struct conv), c_conv);
 306                 if (cp == NULL)
 307                         errx(1, "unknown conversion %s", tmp.name);
 308                 if (ddflags & cp->noset)
 309                         errx(1, "%s: illegal conversion combination", tmp.name);
 310                 ddflags |= cp->set;
 311                 if (cp->ctab)
 312                         ctab = cp->ctab;
 313         }
 314 }
 315
 316 static int
 317 c_conv(const void *a, const void *b)
 318 {
 319
 320         return (strcmp(((const struct conv *)a)->name,
 321             ((const struct conv *)b)->name));
 322 }
 323
 324 /*
 325  * Convert an expression of the following forms to a quad_t.
 326  *      1) A positive decimal number.
 327  *      2) A positive decimal number followed by a b (mult by 512.)
 328  *      3) A positive decimal number followed by a k (mult by 1 << 10.)
 329  *      4) A positive decimal number followed by a m (mult by 1 << 20.)
 330  *      5) A positive decimal number followed by a g (mult by 1 << 30.)
 331  *      5) A positive decimal number followed by a w (mult by sizeof int.)
 332  *      6) Two or more positive decimal numbers (with/without [bkmgw])
 333  *         separated by x (also * for backwards compatibility), specifying
 334  *         the product of the indicated values.
 335  */
 336 static quad_t
 337 get_num(char *val)
 338 {
 339         quad_t num, t;
 340         char *expr;
 341
 342         errno = 0;
 343         num = strtoll(val, &expr, 0);
 344         if (errno != 0)                         /* Overflow or underflow. */
 345                 err(1, "%s", oper);
 346
 347         if (expr == val)                        /* No valid digits. */
 348                 errx(1, "%s: illegal numeric value", oper);
 349
 350         switch (*expr) {
 351         case 'b':
 352                 t = num;
 353                 num *= 512;
 354                 if (t > num)
 355                         goto erange;
 356                 ++expr;
 357                 break;
 358         case 'k':
 359                 t = num;
 360                 num *= 1 << 10;
 361                 if (t > num)
 362                         goto erange;
 363                 ++expr;
 364                 break;
 365         case 'm':
 366                 t = num;
 367                 num *= 1 << 20;
 368                 if (t > num)
 369                         goto erange;
 370                 ++expr;
 371                 break;
 372         case 'g':
 373                 t = num;
 374                 num *= 1 << 30;
 375                 if (t > num)
 376                         goto erange;
 377                 ++expr;
 378                 break;
 379         case 'w':
 380                 t = num;
 381                 num *= sizeof(int);
 382                 if (t > num)
 383                         goto erange;
 384                 ++expr;
 385                 break;
 386         }
 387
 388         switch (*expr) {
 389                 case '\0':
 390                         break;
 391                 case '*':                       /* Backward compatible. */
 392                 case 'x':
 393                         t = num;
 394                         num *= get_num(expr + 1);
 395                         if (t <= num)
 396                                 break;
 397 erange:
 398                         errx(1, "%s: %s", oper, strerror(ERANGE));
 399                 default:
 400                         errx(1, "%s: illegal numeric value", oper);
 401         }
 402         return (num);
 403 }
 404
 405 static off_t
 406 get_offset(char *val)
 407 {
 408         quad_t num;
 409
 410         num = get_num(val);
 411         if (num > QUAD_MAX)     /* XXX can't happen && quad_t != off_t */
 412                 errx(1, "%s: illegal offset", oper);    /* Too big. */
 413         return ((off_t)num);
 414 }