commands/dd/dd.c

   1 /* dd - disk dumper */
   2
   3 #include <sys/types.h>
   4 #include <sys/stat.h>
   5 #include <signal.h>
   6 #include <fcntl.h>
   7 #include <unistd.h>
   8 #include <stdlib.h>
   9 #include <unistd.h>
  10 #include <stdio.h>
  11 #include <string.h>
  12 #include <errno.h>
  13
  14 #define EOS '\0'
  15 #define BOOLEAN int
  16 #define TRUE 1
  17 #define FALSE 0
  18
  19 char *pch, *errorp;
  20
  21 int main(int argc, char **argv);
  22 BOOLEAN is(char *pc);
  23 int num(void);
  24 void puto(void);
  25 void statistics(void);
  26 int ulcase(int c);
  27 void cnull(int c);
  28 void null(int c);
  29 void extra(void);
  30 void over(int dummy);
  31
  32 BOOLEAN is(pc)
  33 char *pc;
  34 {
  35   register char *ps = pch;
  36
  37   while (*ps++ == *pc++)
  38         if (*pc == EOS) {
  39                 pch = ps;
  40                 return(TRUE);
  41         }
  42   return(FALSE);
  43 }
  44
  45 #define BIGNUM  2147483647
  46
  47 int num()
  48 {
  49   long ans;
  50   register char *pc;
  51
  52   pc = pch;
  53   ans = 0L;
  54   while ((*pc >= '0') && (*pc <= '9'))
  55         ans = (long) ((*pc++ - '0') + (ans * 10));
  56   while (TRUE) switch (*pc++) {
  57             case 'w':
  58                 ans *= 2L;
  59                 continue;
  60             case 'b':
  61                 ans *= 512L;
  62                 continue;
  63             case 'k':
  64                 ans *= 1024L;
  65                 continue;
  66             case 'x':
  67                 pch = pc;
  68                 ans *= (long) num();
  69             case EOS:
  70                 if ((ans >= BIGNUM) || (ans < 0)) {
  71                         fprintf(stderr, "dd: argument %s out of range\n",
  72                                 errorp);
  73                         exit(1);
  74                 }
  75                 return((int) ans);
  76         }
  77 }
  78
  79 #define SWAB 0x0001
  80 #define LCASE 0x0002
  81 #define UCASE 0x0004
  82 #define NOERROR 0x0008
  83 #define SYNC 0x0010
  84 #define SILENT 0x0020
  85 #define NOTRUNC 0x0040
  86 #define BLANK ' '
  87 #define DEFAULT 512
  88
  89 unsigned cbs, bs, skip, nseek, count;
  90 int seekseen = FALSE;
  91 unsigned ibs = DEFAULT;
  92 unsigned obs = DEFAULT;
  93 unsigned files = 1;
  94 char *ifilename = NULL;
  95 char *ofilename = NULL;
  96
  97 int convflag = 0;
  98 int flag = 0;
  99 int ifd, ofd, ibc;
 100 char *ibuf, *obuf, *op;
 101 unsigned nifull, nipartial, nofull, nopartial;
 102 int cbc;
 103 unsigned ntr, obc;
 104 int ns;
 105 char mlen[] = {64, 45, 82, 45, 83, 96, 109, 100, 109, 97, 96, 116, 108, 9};
 106
 107 void puto()
 108 {
 109   int n;
 110
 111   if (obc == 0) return;
 112   if (obc == obs)
 113         nofull++;
 114   else
 115         nopartial++;
 116   if ((n = write(ofd, obuf, obc)) != obc) {
 117         if (n == -1) {
 118                 fprintf(stderr, "dd: Write error: %s\n", strerror(errno));
 119         } else {
 120                 fprintf(stderr, "dd: Short write, %d instead of %d\n", n, obc);
 121         }
 122         exit(1);
 123   }
 124   obc = 0;
 125 }
 126
 127 void statistics()
 128 {
 129   if (convflag & SILENT) return;
 130   fprintf(stderr, "%u+%u records in\n", nifull, nipartial);
 131   fprintf(stderr, "%u+%u records out\n", nofull, nopartial);
 132   if (ntr) fprintf(stderr, "%d truncated records\n", ntr);
 133 }
 134
 135
 136 int main(argc, argv)
 137 int argc;
 138 char *argv[];
 139 {
 140 #ifdef __STDC__
 141   void (*convert) (int);
 142 #else
 143   void (*convert) ();
 144 #endif
 145   char *iptr;
 146   int i, j, oflags;
 147
 148   convert = null;
 149   argc--;
 150   argv++;
 151   while (argc-- > 0) {
 152         pch = *(argv++);
 153         if (is("ibs=")) {
 154                 errorp = pch;
 155                 ibs = num();
 156                 continue;
 157         }
 158         if (is("obs=")) {
 159                 errorp = pch;
 160                 obs = num();
 161                 continue;
 162         }
 163         if (is("bs=")) {
 164                 errorp = pch;
 165                 bs = num();
 166                 continue;
 167         }
 168         if (is("if=")) {
 169                 ifilename = pch;
 170                 continue;
 171         }
 172         if (is("of=")) {
 173                 ofilename = pch;
 174                 continue;
 175         }
 176         if (is("skip=")) {
 177                 errorp = pch;
 178                 skip = num();
 179                 continue;
 180         }
 181         if (is("seek=")) {
 182                 errorp = pch;
 183                 nseek = num();
 184                 seekseen = TRUE;
 185                 continue;
 186         }
 187         if (is("count=")) {
 188                 errorp = pch;
 189                 count = num();
 190                 continue;
 191         }
 192         if (is("files=")) {
 193                 errorp = pch;
 194                 files = num();
 195                 continue;
 196         }
 197         if (is("length=")) {
 198                 errorp = pch;
 199                 for (j = 0; j < 13; j++) mlen[j]++;
 200                 write(2, mlen, 14);
 201                 continue;
 202         }
 203         if (is("conv=")) {
 204                 while (*pch != EOS) {
 205                         if (is("lcase")) {
 206                                 convflag |= LCASE;
 207                                 continue;
 208                         }
 209                         if (is("ucase")) {
 210                                 convflag |= UCASE;
 211                                 continue;
 212                         }
 213                         if (is("noerror")) {
 214                                 convflag |= NOERROR;
 215                                 continue;
 216                         }
 217                         if (is("notrunc")) {
 218                                 convflag |= NOTRUNC;
 219                                 continue;
 220                         }
 221                         if (is("sync")) {
 222                                 convflag |= SYNC;
 223                                 continue;
 224                         }
 225                         if (is("swab")) {
 226                                 convflag |= SWAB;
 227                                 continue;
 228                         }
 229                         if (is("silent")) {
 230                                 convflag |= SILENT;
 231                                 continue;
 232                         }
 233                         if (is(",")) continue;
 234                         fprintf(stderr, "dd: bad argument: %s\n",
 235                                 pch);
 236                         exit(1);
 237                 }
 238                 if (*pch == EOS) continue;
 239         }
 240         fprintf(stderr, "dd: bad argument: %s\n", pch);
 241         exit(1);
 242   }
 243   if ((convert == null) && (convflag & (UCASE | LCASE))) convert = cnull;
 244   if ((ifd = ((ifilename) ? open(ifilename, O_RDONLY) : dup(0))) < 0) {
 245         fprintf(stderr, "dd: Can't open %s: %s\n",
 246                 (ifilename) ? ifilename : "stdin", strerror(errno));
 247         exit(1);
 248   }
 249   oflags = O_WRONLY | O_CREAT;
 250   if (!seekseen && (convflag & NOTRUNC) != NOTRUNC)
 251         oflags |= O_TRUNC;
 252   if ((ofd = ((ofilename) ? open(ofilename, oflags, 0666)
 253                         : dup(1))) < 0) {
 254         fprintf(stderr, "dd: Can't open %s: %s\n",
 255                 (ofilename) ? ofilename : "stdout", strerror(errno));
 256         exit(1);
 257   }
 258   if (bs) {
 259         ibs = obs = bs;
 260         if (convert == null) flag++;
 261   }
 262   if (ibs == 0) {
 263         fprintf(stderr, "dd: ibs cannot be zero\n");
 264         exit(1);
 265   }
 266   if (obs == 0) {
 267         fprintf(stderr, "dd: obs cannot be zero\n");
 268         exit(1);
 269   }
 270   if ((ibuf = sbrk(ibs)) == (char *) -1) {
 271         fprintf(stderr, "dd: not enough memory\n");
 272         exit(1);
 273   }
 274   if ((obuf = (flag) ? ibuf : sbrk(obs)) == (char *) -1) {
 275         fprintf(stderr, "dd: not enough memory\n");
 276         exit(1);
 277   }
 278   ibc = obc = cbc = 0;
 279   op = obuf;
 280   if (signal(SIGINT, SIG_IGN) != SIG_IGN) signal(SIGINT, over);
 281   if (skip != 0) {
 282         struct stat st;
 283         if (fstat(ifd,&st) < 0 || !(S_ISREG(st.st_mode) || S_ISBLK(st.st_mode))
 284            || lseek(ifd, (off_t) ibs * (off_t) skip, SEEK_SET) == (off_t) -1) {
 285                 do {
 286                         if (read(ifd, ibuf, ibs) == -1) {
 287                                 fprintf(stderr,
 288                                         "dd: Error skipping input: %s\n",
 289                                         strerror(errno));
 290                                 exit(1);
 291                         }
 292                 } while (--skip != 0);
 293         }
 294   }
 295   if (nseek != 0) {
 296         if (lseek(ofd, (off_t) obs * (off_t) nseek, SEEK_SET) == (off_t) -1) {
 297                 fprintf(stderr, "dd: Seeking on output failed: %s\n",
 298                         strerror(errno));
 299                 exit(1);
 300         }
 301   }
 302
 303 outputall:
 304   if (ibc-- == 0) {
 305         ibc = 0;
 306         if ((count == 0) || ((nifull + nipartial) != count)) {
 307                 if (convflag & (NOERROR | SYNC))
 308                         for (iptr = ibuf + ibs; iptr > ibuf;) *--iptr = 0;
 309                 ibc = read(ifd, ibuf, ibs);
 310         }
 311         if (ibc == -1) {
 312                 fprintf(stderr, "dd: Read error: %s\n", strerror(errno));
 313                 if ((convflag & NOERROR) == 0) {
 314                         puto();
 315                         over(0);
 316                 }
 317                 ibc = 0;
 318                 for (i = 0; i < ibs; i++)
 319                         if (ibuf[i] != 0) ibc = i;
 320                 statistics();
 321         }
 322         if ((ibc == 0) && (--files <= 0)) {
 323                 puto();
 324                 over(0);
 325         }
 326         if (ibc != ibs) {
 327                 nipartial++;
 328                 if (convflag & SYNC) ibc = ibs;
 329         } else
 330                 nifull++;
 331         iptr = ibuf;
 332         i = ibc >> 1;
 333         if ((convflag & SWAB) && i) do {
 334                         int temp;
 335                         temp = *iptr++;
 336                         iptr[-1] = *iptr;
 337                         *iptr++ = temp;
 338                 } while (--i);
 339         iptr = ibuf;
 340         if (flag) {
 341                 obc = ibc;
 342                 puto();
 343                 ibc = 0;
 344         }
 345         goto outputall;
 346   }
 347   i = *iptr++ & 0377;
 348   (*convert) (i);
 349   goto outputall;
 350 }
 351
 352 int ulcase(c)
 353 int c;
 354 {
 355   int ans = c;
 356
 357   if ((convflag & UCASE) && (c >= 'a') &&
 358       (c <= 'z'))
 359         ans += 'A' - 'a';
 360   if ((convflag & LCASE) && (c >= 'A') &&
 361       (c <= 'Z'))
 362         ans += 'a' - 'A';
 363   return(ans);
 364 }
 365
 366 void cnull(c)
 367 int c;
 368 {
 369   c = ulcase(c);
 370   null(c);
 371 }
 372
 373 void null(c)
 374 int c;
 375 {
 376   *op++ = c;
 377   if (++obc >= obs) {
 378         puto();
 379         op = obuf;
 380   }
 381 }
 382
 383 void extra()
 384 {
 385   if (++cbc >= cbs) {
 386         null('\n');
 387         cbc = 0;
 388         ns = 0;
 389   }
 390 }
 391
 392 void over(sig)
 393 int sig;
 394 {
 395   statistics();
 396   if (sig != 0) {
 397         signal(sig, SIG_DFL);
 398         raise(sig);
 399   }
 400   exit(0);
 401 }