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
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "@(#)args.c      8.3 (Berkeley) 4/2/94";
  41 #endif
  42 static const char rcsid[] =
  43   "$FreeBSD: src/bin/dd/args.c,v 1.31 2002/02/22 20:51:00 markm Exp $";
  44 #endif /* not lint */
  45
  46 #include <sys/types.h>
  47
  48 #include <err.h>
  49 #include <errno.h>
  50 #include <limits.h>
  51 #include <stdlib.h>
  52 #include <string.h>
  53
  54 #include "dd.h"
  55 #include "extern.h"
  56
  57 static int      c_arg(const void *, const void *);
  58 static int      c_conv(const void *, const void *);
  59 static void     f_bs(char *);
  60 static void     f_cbs(char *);
  61 static void     f_conv(char *);
  62 static void     f_count(char *);
  63 static void     f_files(char *);
  64 static void     f_ibs(char *);
  65 static void     f_if(char *);
  66 static void     f_obs(char *);
  67 static void     f_of(char *);
  68 static void     f_seek(char *);
  69 static void     f_skip(char *);
  70 static quad_t   get_num(char *);
  71 static off_t    get_offset(char *);
  72
  73 static const struct arg {
  74         const char *name;
  75         void (*f)(char *);
  76         u_int set, noset;
  77 } args[] = {
  78         { "bs",         f_bs,           C_BS,    C_BS|C_IBS|C_OBS|C_OSYNC },
  79         { "cbs",        f_cbs,          C_CBS,   C_CBS },
  80         { "conv",       f_conv,         0,       0 },
  81         { "count",      f_count,        C_COUNT, C_COUNT },
  82         { "files",      f_files,        C_FILES, C_FILES },
  83         { "ibs",        f_ibs,          C_IBS,   C_BS|C_IBS },
  84         { "if",         f_if,           C_IF,    C_IF },
  85         { "iseek",      f_skip,         C_SKIP,  C_SKIP },
  86         { "obs",        f_obs,          C_OBS,   C_BS|C_OBS },
  87         { "of",         f_of,           C_OF,    C_OF },
  88         { "oseek",      f_seek,         C_SEEK,  C_SEEK },
  89         { "seek",       f_seek,         C_SEEK,  C_SEEK },
  90         { "skip",       f_skip,         C_SKIP,  C_SKIP },
  91 };
  92
  93 static char *oper;
  94
  95 /*
  96  * args -- parse JCL syntax of dd.
  97  */
  98 void
  99 jcl(char **argv)
 100 {
 101         struct arg *ap, tmp;
 102         char *arg;
 103
 104         in.dbsz = out.dbsz = 512;
 105
 106         while ((oper = *++argv) != NULL) {
 107                 if ((oper = strdup(oper)) == NULL)
 108                         errx(1, "unable to allocate space for the argument \"%s\"", *argv);
 109                 if ((arg = strchr(oper, '=')) == NULL)
 110                         errx(1, "unknown operand %s", oper);
 111                 *arg++ = '\0';
 112                 if (!*arg)
 113                         errx(1, "no value specified for %s", oper);
 114                 tmp.name = oper;
 115                 if (!(ap = (struct arg *)bsearch(&tmp, args,
 116                     sizeof(args)/sizeof(struct arg), sizeof(struct arg),
 117                     c_arg)))
 118                         errx(1, "unknown operand %s", tmp.name);
 119                 if (ddflags & ap->noset)
 120                         errx(1, "%s: illegal argument combination or already set",
 121                             tmp.name);
 122                 ddflags |= ap->set;
 123                 ap->f(arg);
 124         }
 125
 126         /* Final sanity checks. */
 127
 128         if (ddflags & C_BS) {
 129                 /*
 130                  * Bs is turned off by any conversion -- we assume the user
 131                  * just wanted to set both the input and output block sizes
 132                  * and didn't want the bs semantics, so we don't warn.
 133                  */
 134                 if (ddflags & (C_BLOCK | C_LCASE | C_SWAB | C_UCASE |
 135                     C_UNBLOCK))
 136                         ddflags &= ~C_BS;
 137
 138                 /* Bs supersedes ibs and obs. */
 139                 if (ddflags & C_BS && ddflags & (C_IBS | C_OBS))
 140                         warnx("bs supersedes ibs and obs");
 141         }
 142
 143         /*
 144          * Ascii/ebcdic and cbs implies block/unblock.
 145          * Block/unblock requires cbs and vice-versa.
 146          */
 147         if (ddflags & (C_BLOCK | C_UNBLOCK)) {
 148                 if (!(ddflags & C_CBS))
 149                         errx(1, "record operations require cbs");
 150                 if (cbsz == 0)
 151                         errx(1, "cbs cannot be zero");
 152                 cfunc = ddflags & C_BLOCK ? block : unblock;
 153         } else if (ddflags & C_CBS) {
 154                 if (ddflags & (C_ASCII | C_EBCDIC)) {
 155                         if (ddflags & C_ASCII) {
 156                                 ddflags |= C_UNBLOCK;
 157                                 cfunc = unblock;
 158                         } else {
 159                                 ddflags |= C_BLOCK;
 160                                 cfunc = block;
 161                         }
 162                 } else
 163                         errx(1, "cbs meaningless if not doing record operations");
 164         } else
 165                 cfunc = def;
 166
 167         /*
 168          * Bail out if the calculation of a file offset would overflow.
 169          */
 170         if (in.offset > QUAD_MAX / in.dbsz || out.offset > QUAD_MAX / out.dbsz)
 171                 errx(1, "seek offsets cannot be larger than %qd", QUAD_MAX);
 172 }
 173
 174 static int
 175 c_arg(const void *a, const void *b)
 176 {
 177
 178         return (strcmp(((const struct arg *)a)->name,
 179             ((const struct arg *)b)->name));
 180 }
 181
 182 static void
 183 f_bs(char *arg)
 184 {
 185         quad_t res;
 186
 187         res = get_num(arg);
 188         if (res < 1 || res > SSIZE_MAX)
 189                 errx(1, "bs must be between 1 and %d", SSIZE_MAX);
 190         in.dbsz = out.dbsz = (size_t)res;
 191 }
 192
 193 static void
 194 f_cbs(char *arg)
 195 {
 196         quad_t res;
 197
 198         res = get_num(arg);
 199         if (res < 1 || res > SSIZE_MAX)
 200                 errx(1, "cbs must be between 1 and %d", SSIZE_MAX);
 201         cbsz = (size_t)res;
 202 }
 203
 204 static void
 205 f_count(char *arg)
 206 {
 207
 208         cpy_cnt = get_num(arg);
 209         if (cpy_cnt < 0)
 210                 errx(1, "count cannot be negative");
 211         if (cpy_cnt == 0)
 212                 cpy_cnt = -1;
 213 }
 214
 215 static void
 216 f_files(char *arg)
 217 {
 218
 219         files_cnt = get_num(arg);
 220         if (files_cnt < 1)
 221                 errx(1, "files must be between 1 and %qd", QUAD_MAX);
 222 }
 223
 224 static void
 225 f_ibs(char *arg)
 226 {
 227         quad_t res;
 228
 229         if (!(ddflags & C_BS)) {
 230                 res = get_num(arg);
 231                 if (res < 1 || res > SSIZE_MAX)
 232                         errx(1, "ibs must be between 1 and %d", SSIZE_MAX);
 233                 in.dbsz = (size_t)res;
 234         }
 235 }
 236
 237 static void
 238 f_if(char *arg)
 239 {
 240
 241         in.name = arg;
 242 }
 243
 244 static void
 245 f_obs(char *arg)
 246 {
 247         quad_t res;
 248
 249         if (!(ddflags & C_BS)) {
 250                 res = get_num(arg);
 251                 if (res < 1 || res > SSIZE_MAX)
 252                         errx(1, "obs must be between 1 and %d", SSIZE_MAX);
 253                 out.dbsz = (size_t)res;
 254         }
 255 }
 256
 257 static void
 258 f_of(char *arg)
 259 {
 260
 261         out.name = arg;
 262 }
 263
 264 static void
 265 f_seek(char *arg)
 266 {
 267
 268         out.offset = get_offset(arg);
 269 }
 270
 271 static void
 272 f_skip(char *arg)
 273 {
 274
 275         in.offset = get_offset(arg);
 276 }
 277
 278 static const struct conv {
 279         const char *name;
 280         u_int set, noset;
 281         const u_char *ctab;
 282 } clist[] = {
 283         { "ascii",      C_ASCII,        C_EBCDIC,       e2a_POSIX },
 284         { "block",      C_BLOCK,        C_UNBLOCK,      NULL },
 285         { "ebcdic",     C_EBCDIC,       C_ASCII,        a2e_POSIX },
 286         { "ibm",        C_EBCDIC,       C_ASCII,        a2ibm_POSIX },
 287         { "lcase",      C_LCASE,        C_UCASE,        NULL },
 288         { "noerror",    C_NOERROR,      0,              NULL },
 289         { "notrunc",    C_NOTRUNC,      0,              NULL },
 290         { "oldascii",   C_ASCII,        C_EBCDIC,       e2a_32V },
 291         { "oldebcdic",  C_EBCDIC,       C_ASCII,        a2e_32V },
 292         { "oldibm",     C_EBCDIC,       C_ASCII,        a2ibm_32V },
 293         { "osync",      C_OSYNC,        C_BS,           NULL },
 294         { "sparse",     C_SPARSE,       0,              NULL },
 295         { "swab",       C_SWAB,         0,              NULL },
 296         { "sync",       C_SYNC,         0,              NULL },
 297         { "ucase",      C_UCASE,        C_LCASE,        NULL },
 298         { "unblock",    C_UNBLOCK,      C_BLOCK,        NULL },
 299 };
 300
 301 static void
 302 f_conv(char *arg)
 303 {
 304         struct conv *cp, tmp;
 305
 306         while (arg != NULL) {
 307                 tmp.name = strsep(&arg, ",");
 308                 cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
 309                     sizeof(struct conv), c_conv);
 310                 if (cp == NULL)
 311                         errx(1, "unknown conversion %s", tmp.name);
 312                 if (ddflags & cp->noset)
 313                         errx(1, "%s: illegal conversion combination", tmp.name);
 314                 ddflags |= cp->set;
 315                 if (cp->ctab)
 316                         ctab = cp->ctab;
 317         }
 318 }
 319
 320 static int
 321 c_conv(const void *a, const void *b)
 322 {
 323
 324         return (strcmp(((const struct conv *)a)->name,
 325             ((const struct conv *)b)->name));
 326 }
 327
 328 /*
 329  * Convert an expression of the following forms to a quad_t.
 330  *      1) A positive decimal number.
 331  *      2) A positive decimal number followed by a b (mult by 512).
 332  *      3) A positive decimal number followed by a k (mult by 1 << 10).
 333  *      4) A positive decimal number followed by a m (mult by 1 << 20).
 334  *      5) A positive decimal number followed by a g (mult by 1 << 30).
 335  *      5) A positive decimal number followed by a w (mult by sizeof int).
 336  *      6) Two or more positive decimal numbers (with/without [bkmgw])
 337  *         separated by x (also * for backwards compatibility), specifying
 338  *         the product of the indicated values.
 339  */
 340 static quad_t
 341 get_num(char *val)
 342 {
 343         quad_t num, t;
 344         char *expr;
 345
 346         errno = 0;
 347         num = strtoq(val, &expr, 0);
 348         if (errno != 0)                         /* Overflow or underflow. */
 349                 err(1, "%s", oper);
 350
 351         if (expr == val)                        /* No valid digits. */
 352                 errx(1, "%s: illegal numeric value", oper);
 353
 354         switch (*expr) {
 355         case 'b':
 356                 t = num;
 357                 num *= 512;
 358                 if (t > num)
 359                         goto erange;
 360                 ++expr;
 361                 break;
 362         case 'k':
 363                 t = num;
 364                 num *= 1 << 10;
 365                 if (t > num)
 366                         goto erange;
 367                 ++expr;
 368                 break;
 369         case 'm':
 370                 t = num;
 371                 num *= 1 << 20;
 372                 if (t > num)
 373                         goto erange;
 374                 ++expr;
 375                 break;
 376         case 'g':
 377                 t = num;
 378                 num *= 1 << 30;
 379                 if (t > num)
 380                         goto erange;
 381                 ++expr;
 382                 break;
 383         case 'w':
 384                 t = num;
 385                 num *= sizeof(int);
 386                 if (t > num)
 387                         goto erange;
 388                 ++expr;
 389                 break;
 390         }
 391
 392         switch (*expr) {
 393                 case '\0':
 394                         break;
 395                 case '*':                       /* Backward compatible. */
 396                 case 'x':
 397                         t = num;
 398                         num *= get_num(expr + 1);
 399                         if (t <= num)
 400                                 break;
 401 erange:
 402                         errx(1, "%s: %s", oper, strerror(ERANGE));
 403                 default:
 404                         errx(1, "%s: illegal numeric value", oper);
 405         }
 406         return (num);
 407 }
 408
 409 static off_t
 410 get_offset(char *val)
 411 {
 412         quad_t num;
 413
 414         num = get_num(val);
 415         if (num > QUAD_MAX)     /* XXX can't happen && quad_t != off_t */
 416                 errx(1, "%s: illegal offset", oper);    /* Too big. */
 417         return ((off_t)num);
 418 }