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. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#)args.c   8.3 (Berkeley) 4/2/94
  34  * $FreeBSD: src/bin/dd/args.c,v 1.25.2.2 2001/01/23 14:20:03 asmodai Exp $
  35  * $DragonFly: src/bin/dd/args.c,v 1.6 2008/01/28 16:08:02 matthias Exp $
  36  */
  37
  38 #include <sys/types.h>
  39
  40 #include <err.h>
  41 #include <errno.h>
  42 #include <limits.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45
  46 #include "dd.h"
  47 #include "extern.h"
  48
  49 static int      c_arg (const void *, const void *);
  50 static int      c_conv (const void *, const void *);
  51 static void     f_bs (char *);
  52 static void     f_cbs (char *);
  53 static void     f_conv (char *);
  54 static void     f_count (char *);
  55 static void     f_files (char *);
  56 static void     f_ibs (char *);
  57 static void     f_if (char *);
  58 static void     f_obs(char *);
  59 static void     f_of (char *);
  60 static void     f_seek (char *);
  61 static void     f_skip (char *);
  62 static quad_t   get_num (char *);
  63 static off_t    get_offset (char *);
  64
  65 static const struct arg {
  66         const char *name;
  67         void (*f) (char *);
  68         u_int set, noset;
  69 } args[] = {
  70         { "bs",         f_bs,           C_BS,    C_BS|C_IBS|C_OBS|C_OSYNC },
  71         { "cbs",        f_cbs,          C_CBS,   C_CBS },
  72         { "conv",       f_conv,         0,       0 },
  73         { "count",      f_count,        C_COUNT, C_COUNT },
  74         { "files",      f_files,        C_FILES, C_FILES },
  75         { "ibs",        f_ibs,          C_IBS,   C_BS|C_IBS },
  76         { "if",         f_if,           C_IF,    C_IF },
  77         { "iseek",      f_skip,         C_SKIP,  C_SKIP },
  78         { "obs",        f_obs,          C_OBS,   C_BS|C_OBS },
  79         { "of",         f_of,           C_OF,    C_OF },
  80         { "oseek",      f_seek,         C_SEEK,  C_SEEK },
  81         { "seek",       f_seek,         C_SEEK,  C_SEEK },
  82         { "skip",       f_skip,         C_SKIP,  C_SKIP },
  83 };
  84
  85 static char *oper;
  86
  87 /*
  88  * args -- parse JCL syntax of dd.
  89  */
  90 void
  91 jcl(char **argv)
  92 {
  93         struct arg *ap, tmp;
  94         char *arg;
  95
  96         in.dbsz = out.dbsz = 512;
  97
  98         while ((oper = *++argv) != NULL) {
  99                 if ((oper = strdup(oper)) == NULL)
 100                         errx(1, "unable to allocate space for the argument \"%s\"", *argv);
 101                 if ((arg = strchr(oper, '=')) == NULL)
 102                         errx(1, "unknown operand %s", oper);
 103                 *arg++ = '\0';
 104                 if (!*arg)
 105                         errx(1, "no value specified for %s", oper);
 106                 tmp.name = oper;
 107                 if (!(ap = (struct arg *)bsearch(&tmp, args,
 108                     sizeof(args)/sizeof(struct arg), sizeof(struct arg),
 109                     c_arg)))
 110                         errx(1, "unknown operand %s", tmp.name);
 111                 if (ddflags & ap->noset)
 112                         errx(1, "%s: illegal argument combination or already set",
 113                             tmp.name);
 114                 ddflags |= ap->set;
 115                 ap->f(arg);
 116         }
 117
 118         /* Final sanity checks. */
 119
 120         if (ddflags & C_BS) {
 121                 /*
 122                  * Bs is turned off by any conversion -- we assume the user
 123                  * just wanted to set both the input and output block sizes
 124                  * and didn't want the bs semantics, so we don't warn.
 125                  */
 126                 if (ddflags & (C_BLOCK | C_LCASE | C_SWAB | C_UCASE |
 127                     C_UNBLOCK))
 128                         ddflags &= ~C_BS;
 129
 130                 /* Bs supersedes ibs and obs. */
 131                 if (ddflags & C_BS && ddflags & (C_IBS | C_OBS))
 132                         warnx("bs supersedes ibs and obs");
 133         }
 134
 135         /*
 136          * Ascii/ebcdic and cbs implies block/unblock.
 137          * Block/unblock requires cbs and vice-versa.
 138          */
 139         if (ddflags & (C_BLOCK | C_UNBLOCK)) {
 140                 if (!(ddflags & C_CBS))
 141                         errx(1, "record operations require cbs");
 142                 if (cbsz == 0)
 143                         errx(1, "cbs cannot be zero");
 144                 cfunc = ddflags & C_BLOCK ? block : unblock;
 145         } else if (ddflags & C_CBS) {
 146                 if (ddflags & (C_ASCII | C_EBCDIC)) {
 147                         if (ddflags & C_ASCII) {
 148                                 ddflags |= C_UNBLOCK;
 149                                 cfunc = unblock;
 150                         } else {
 151                                 ddflags |= C_BLOCK;
 152                                 cfunc = block;
 153                         }
 154                 } else
 155                         errx(1, "cbs meaningless if not doing record operations");
 156         } else
 157                 cfunc = def;
 158
 159         /*
 160          * Bail out if the calculation of a file offset would overflow.
 161          */
 162         if (in.offset > QUAD_MAX / in.dbsz || out.offset > QUAD_MAX / out.dbsz)
 163                 errx(1, "seek offsets cannot be larger than %lld", QUAD_MAX);
 164 }
 165
 166 static int
 167 c_arg(const void *a, const void *b)
 168 {
 169
 170         return (strcmp(((const struct arg *)a)->name,
 171             ((const struct arg *)b)->name));
 172 }
 173
 174 static void
 175 f_bs(char *arg)
 176 {
 177         quad_t res;
 178
 179         res = get_num(arg);
 180         if (res < 1 || res > SSIZE_MAX)
 181                 errx(1, "bs must be between 1 and %d", SSIZE_MAX);
 182         in.dbsz = out.dbsz = (size_t)res;
 183 }
 184
 185 static void
 186 f_cbs(char *arg)
 187 {
 188         quad_t res;
 189
 190         res = get_num(arg);
 191         if (res < 1 || res > SSIZE_MAX)
 192                 errx(1, "cbs must be between 1 and %d", SSIZE_MAX);
 193         cbsz = (size_t)res;
 194 }
 195
 196 static void
 197 f_count(char *arg)
 198 {
 199
 200         cpy_cnt = get_num(arg);
 201         if (cpy_cnt < 0)
 202                 errx(1, "count cannot be negative");
 203         if (cpy_cnt == 0)
 204                 cpy_cnt = -1;
 205 }
 206
 207 static void
 208 f_files(char *arg)
 209 {
 210
 211         files_cnt = get_num(arg);
 212         if (files_cnt < 1)
 213                 errx(1, "files must be between 1 and %qd", QUAD_MAX);
 214 }
 215
 216 static void
 217 f_ibs(char *arg)
 218 {
 219         quad_t res;
 220
 221         if (!(ddflags & C_BS)) {
 222                 res = get_num(arg);
 223                 if (res < 1 || res > SSIZE_MAX)
 224                         errx(1, "ibs must be between 1 and %d", SSIZE_MAX);
 225                 in.dbsz = (size_t)res;
 226         }
 227 }
 228
 229 static void
 230 f_if(char *arg)
 231 {
 232
 233         in.name = arg;
 234 }
 235
 236 static void
 237 f_obs(char *arg)
 238 {
 239         quad_t res;
 240
 241         if (!(ddflags & C_BS)) {
 242                 res = get_num(arg);
 243                 if (res < 1 || res > SSIZE_MAX)
 244                         errx(1, "obs must be between 1 and %d", SSIZE_MAX);
 245                 out.dbsz = (size_t)res;
 246         }
 247 }
 248
 249 static void
 250 f_of(char *arg)
 251 {
 252
 253         out.name = arg;
 254 }
 255
 256 static void
 257 f_seek(char *arg)
 258 {
 259
 260         out.offset = get_offset(arg);
 261 }
 262
 263 static void
 264 f_skip(char *arg)
 265 {
 266
 267         in.offset = get_offset(arg);
 268 }
 269
 270 static const struct conv {
 271         const char *name;
 272         u_int set, noset;
 273         const u_char *ctab;
 274 } clist[] = {
 275         { "ascii",      C_ASCII,        C_EBCDIC,       e2a_POSIX },
 276         { "block",      C_BLOCK,        C_UNBLOCK,      NULL },
 277         { "ebcdic",     C_EBCDIC,       C_ASCII,        a2e_POSIX },
 278         { "ibm",        C_EBCDIC,       C_ASCII,        a2ibm_POSIX },
 279         { "lcase",      C_LCASE,        C_UCASE,        NULL },
 280         { "noerror",    C_NOERROR,      0,              NULL },
 281         { "notrunc",    C_NOTRUNC,      0,              NULL },
 282         { "oldascii",   C_ASCII,        C_EBCDIC,       e2a_32V },
 283         { "oldebcdic",  C_EBCDIC,       C_ASCII,        a2e_32V },
 284         { "oldibm",     C_EBCDIC,       C_ASCII,        a2ibm_32V },
 285         { "osync",      C_OSYNC,        C_BS,           NULL },
 286         { "sparse",     C_SPARSE,       0,              NULL },
 287         { "swab",       C_SWAB,         0,              NULL },
 288         { "sync",       C_SYNC,         0,              NULL },
 289         { "ucase",      C_UCASE,        C_LCASE,        NULL },
 290         { "unblock",    C_UNBLOCK,      C_BLOCK,        NULL },
 291 };
 292
 293 static void
 294 f_conv(char *arg)
 295 {
 296         struct conv *cp, tmp;
 297
 298         while (arg != NULL) {
 299                 tmp.name = strsep(&arg, ",");
 300                 cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
 301                     sizeof(struct conv), c_conv);
 302                 if (cp == NULL)
 303                         errx(1, "unknown conversion %s", tmp.name);
 304                 if (ddflags & cp->noset)
 305                         errx(1, "%s: illegal conversion combination", tmp.name);
 306                 ddflags |= cp->set;
 307                 if (cp->ctab)
 308                         ctab = cp->ctab;
 309         }
 310 }
 311
 312 static int
 313 c_conv(const void *a, const void *b)
 314 {
 315
 316         return (strcmp(((const struct conv *)a)->name,
 317             ((const struct conv *)b)->name));
 318 }
 319
 320 /*
 321  * Convert an expression of the following forms to a quad_t.
 322  *      1) A positive decimal number.
 323  *      2) A positive decimal number followed by a b (mult by 512.)
 324  *      3) A positive decimal number followed by a k (mult by 1 << 10.)
 325  *      4) A positive decimal number followed by a m (mult by 1 << 20.)
 326  *      5) A positive decimal number followed by a g (mult by 1 << 30.)
 327  *      5) A positive decimal number followed by a w (mult by sizeof int.)
 328  *      6) Two or more positive decimal numbers (with/without [bkmgw])
 329  *         separated by x (also * for backwards compatibility), specifying
 330  *         the product of the indicated values.
 331  */
 332 static quad_t
 333 get_num(char *val)
 334 {
 335         quad_t num, t;
 336         char *expr;
 337
 338         errno = 0;
 339         num = strtoll(val, &expr, 0);
 340         if (errno != 0)                         /* Overflow or underflow. */
 341                 err(1, "%s", oper);
 342
 343         if (expr == val)                        /* No valid digits. */
 344                 errx(1, "%s: illegal numeric value", oper);
 345
 346         switch (*expr) {
 347         case 'b':
 348         case 'B':
 349                 t = num;
 350                 num *= 512;
 351                 if (t > num)
 352                         goto erange;
 353                 ++expr;
 354                 break;
 355         case 'k':
 356         case 'K':
 357                 t = num;
 358                 num *= 1 << 10;
 359                 if (t > num)
 360                         goto erange;
 361                 ++expr;
 362                 break;
 363         case 'm':
 364         case 'M':
 365                 t = num;
 366                 num *= 1 << 20;
 367                 if (t > num)
 368                         goto erange;
 369                 ++expr;
 370                 break;
 371         case 'g':
 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 }