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 * 4. 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 34 #if 0 35 #ifndef lint 36 static char const copyright[] = 37 "@(#) Copyright (c) 1991, 1993, 1994\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39 #endif /* not lint */ 40 41 #ifndef lint 42 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94"; 43 #endif /* not lint */ 44 #endif 45 #include <sys/cdefs.h> 46 __FBSDID("$FreeBSD$"); 47 48 #include <sys/param.h> 49 #include <sys/stat.h> 50 #include <sys/conf.h> 51 #include <sys/disklabel.h> 52 #include <sys/filio.h> 53 54 #include <assert.h> 55 #include <ctype.h> 56 #include <err.h> 57 #include <errno.h> 58 #include <fcntl.h> 59 #include <inttypes.h> 60 #include <locale.h> 61 #include <stdio.h> 62 #include <stdlib.h> 63 #include <string.h> 64 #include <time.h> 65 #include <unistd.h> 66 67 #include "dd.h" 68 #include "extern.h" 69 70 static void dd_close(void); 71 static void dd_in(void); 72 static void getfdtype(IO *); 73 static void setup(void); 74 75 IO in, out; /* input/output state */ 76 STAT st; /* statistics */ 77 void (*cfunc)(void); /* conversion function */ 78 uintmax_t cpy_cnt; /* # of blocks to copy */ 79 static off_t pending = 0; /* pending seek if sparse */ 80 u_int ddflags = 0; /* conversion options */ 81 size_t cbsz; /* conversion block size */ 82 uintmax_t files_cnt = 1; /* # of files to copy */ 83 const u_char *ctab; /* conversion table */ 84 char fill_char; /* Character to fill with if defined */ 85 size_t speed = 0; /* maximum speed, in bytes per second */ 86 volatile sig_atomic_t need_summary; 87 88 int 89 main(int argc __unused, char *argv[]) 90 { 91 (void)setlocale(LC_CTYPE, ""); 92 jcl(argv); 93 setup(); 94 95 (void)signal(SIGINFO, siginfo_handler); 96 (void)signal(SIGINT, terminate); 97 98 atexit(summary); 99 100 while (files_cnt--) 101 dd_in(); 102 103 dd_close(); 104 /* 105 * Some devices such as cfi(4) may perform significant amounts 106 * of work when a write descriptor is closed. Close the out 107 * descriptor explicitly so that the summary handler (called 108 * from an atexit() hook) includes this work. 109 */ 110 close(out.fd); 111 exit(0); 112 } 113 114 static int 115 parity(u_char c) 116 { 117 int i; 118 119 i = c ^ (c >> 1) ^ (c >> 2) ^ (c >> 3) ^ 120 (c >> 4) ^ (c >> 5) ^ (c >> 6) ^ (c >> 7); 121 return (i & 1); 122 } 123 124 static void 125 setup(void) 126 { 127 u_int cnt; 128 129 if (in.name == NULL) { 130 in.name = "stdin"; 131 in.fd = STDIN_FILENO; 132 } else { 133 in.fd = open(in.name, O_RDONLY, 0); 134 if (in.fd == -1) 135 err(1, "%s", in.name); 136 } 137 138 getfdtype(&in); 139 140 if (files_cnt > 1 && !(in.flags & ISTAPE)) 141 errx(1, "files is not supported for non-tape devices"); 142 143 if (out.name == NULL) { 144 /* No way to check for read access here. */ 145 out.fd = STDOUT_FILENO; 146 out.name = "stdout"; 147 } else { 148 #define OFLAGS \ 149 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 150 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 151 /* 152 * May not have read access, so try again with write only. 153 * Without read we may have a problem if output also does 154 * not support seeks. 155 */ 156 if (out.fd == -1) { 157 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 158 out.flags |= NOREAD; 159 } 160 if (out.fd == -1) 161 err(1, "%s", out.name); 162 } 163 164 getfdtype(&out); 165 166 /* 167 * Allocate space for the input and output buffers. If not doing 168 * record oriented I/O, only need a single buffer. 169 */ 170 if (!(ddflags & (C_BLOCK | C_UNBLOCK))) { 171 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 172 err(1, "input buffer"); 173 out.db = in.db; 174 } else if ((in.db = malloc(MAX(in.dbsz, cbsz) + cbsz)) == NULL || 175 (out.db = malloc(out.dbsz + cbsz)) == NULL) 176 err(1, "output buffer"); 177 178 /* dbp is the first free position in each buffer. */ 179 in.dbp = in.db; 180 out.dbp = out.db; 181 182 /* Position the input/output streams. */ 183 if (in.offset) 184 pos_in(); 185 if (out.offset) 186 pos_out(); 187 188 /* 189 * Truncate the output file. If it fails on a type of output file 190 * that it should _not_ fail on, error out. 191 */ 192 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK) && 193 out.flags & ISTRUNC) 194 if (ftruncate(out.fd, out.offset * out.dbsz) == -1) 195 err(1, "truncating %s", out.name); 196 197 if (ddflags & (C_LCASE | C_UCASE | C_ASCII | C_EBCDIC | C_PARITY)) { 198 if (ctab != NULL) { 199 for (cnt = 0; cnt <= 0377; ++cnt) 200 casetab[cnt] = ctab[cnt]; 201 } else { 202 for (cnt = 0; cnt <= 0377; ++cnt) 203 casetab[cnt] = cnt; 204 } 205 if ((ddflags & C_PARITY) && !(ddflags & C_ASCII)) { 206 /* 207 * If the input is not EBCDIC, and we do parity 208 * processing, strip input parity. 209 */ 210 for (cnt = 200; cnt <= 0377; ++cnt) 211 casetab[cnt] = casetab[cnt & 0x7f]; 212 } 213 if (ddflags & C_LCASE) { 214 for (cnt = 0; cnt <= 0377; ++cnt) 215 casetab[cnt] = tolower(casetab[cnt]); 216 } else if (ddflags & C_UCASE) { 217 for (cnt = 0; cnt <= 0377; ++cnt) 218 casetab[cnt] = toupper(casetab[cnt]); 219 } 220 if ((ddflags & C_PARITY)) { 221 /* 222 * This should strictly speaking be a no-op, but I 223 * wonder what funny LANG settings could get us. 224 */ 225 for (cnt = 0; cnt <= 0377; ++cnt) 226 casetab[cnt] = casetab[cnt] & 0x7f; 227 } 228 if ((ddflags & C_PARSET)) { 229 for (cnt = 0; cnt <= 0377; ++cnt) 230 casetab[cnt] = casetab[cnt] | 0x80; 231 } 232 if ((ddflags & C_PAREVEN)) { 233 for (cnt = 0; cnt <= 0377; ++cnt) 234 if (parity(casetab[cnt])) 235 casetab[cnt] = casetab[cnt] | 0x80; 236 } 237 if ((ddflags & C_PARODD)) { 238 for (cnt = 0; cnt <= 0377; ++cnt) 239 if (!parity(casetab[cnt])) 240 casetab[cnt] = casetab[cnt] | 0x80; 241 } 242 243 ctab = casetab; 244 } 245 246 if (clock_gettime(CLOCK_MONOTONIC, &st.start)) 247 err(1, "clock_gettime"); 248 } 249 250 static void 251 getfdtype(IO *io) 252 { 253 struct stat sb; 254 int type; 255 256 if (fstat(io->fd, &sb) == -1) 257 err(1, "%s", io->name); 258 if (S_ISREG(sb.st_mode)) 259 io->flags |= ISTRUNC; 260 if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) { 261 if (ioctl(io->fd, FIODTYPE, &type) == -1) { 262 err(1, "%s", io->name); 263 } else { 264 if (type & D_TAPE) 265 io->flags |= ISTAPE; 266 else if (type & (D_DISK | D_MEM)) 267 io->flags |= ISSEEK; 268 if (S_ISCHR(sb.st_mode) && (type & D_TAPE) == 0) 269 io->flags |= ISCHR; 270 } 271 return; 272 } 273 errno = 0; 274 if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 275 io->flags |= ISPIPE; 276 else 277 io->flags |= ISSEEK; 278 } 279 280 /* 281 * Limit the speed by adding a delay before every block read. 282 * The delay (t_usleep) is equal to the time computed from block 283 * size and the specified speed limit (t_target) minus the time 284 * spent on actual read and write operations (t_io). 285 */ 286 static void 287 speed_limit(void) 288 { 289 static double t_prev, t_usleep; 290 double t_now, t_io, t_target; 291 292 t_now = secs_elapsed(); 293 t_io = t_now - t_prev - t_usleep; 294 t_target = (double)in.dbsz / (double)speed; 295 t_usleep = t_target - t_io; 296 if (t_usleep > 0) 297 usleep(t_usleep * 1000000); 298 else 299 t_usleep = 0; 300 t_prev = t_now; 301 } 302 303 static void 304 dd_in(void) 305 { 306 ssize_t n; 307 308 for (;;) { 309 switch (cpy_cnt) { 310 case -1: /* count=0 was specified */ 311 return; 312 case 0: 313 break; 314 default: 315 if (st.in_full + st.in_part >= (uintmax_t)cpy_cnt) 316 return; 317 break; 318 } 319 320 if (speed > 0) 321 speed_limit(); 322 323 /* 324 * Zero the buffer first if sync; if doing block operations, 325 * use spaces. 326 */ 327 if (ddflags & C_SYNC) { 328 if (ddflags & C_FILL) 329 memset(in.dbp, fill_char, in.dbsz); 330 else if (ddflags & (C_BLOCK | C_UNBLOCK)) 331 memset(in.dbp, ' ', in.dbsz); 332 else 333 memset(in.dbp, 0, in.dbsz); 334 } 335 336 n = read(in.fd, in.dbp, in.dbsz); 337 if (n == 0) { 338 in.dbrcnt = 0; 339 return; 340 } 341 342 /* Read error. */ 343 if (n == -1) { 344 /* 345 * If noerror not specified, die. POSIX requires that 346 * the warning message be followed by an I/O display. 347 */ 348 if (!(ddflags & C_NOERROR)) 349 err(1, "%s", in.name); 350 warn("%s", in.name); 351 summary(); 352 353 /* 354 * If it's a seekable file descriptor, seek past the 355 * error. If your OS doesn't do the right thing for 356 * raw disks this section should be modified to re-read 357 * in sector size chunks. 358 */ 359 if (in.flags & ISSEEK && 360 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 361 warn("%s", in.name); 362 363 /* If sync not specified, omit block and continue. */ 364 if (!(ddflags & C_SYNC)) 365 continue; 366 367 /* Read errors count as full blocks. */ 368 in.dbcnt += in.dbrcnt = in.dbsz; 369 ++st.in_full; 370 371 /* Handle full input blocks. */ 372 } else if ((size_t)n == in.dbsz) { 373 in.dbcnt += in.dbrcnt = n; 374 ++st.in_full; 375 376 /* Handle partial input blocks. */ 377 } else { 378 /* If sync, use the entire block. */ 379 if (ddflags & C_SYNC) 380 in.dbcnt += in.dbrcnt = in.dbsz; 381 else 382 in.dbcnt += in.dbrcnt = n; 383 ++st.in_part; 384 } 385 386 /* 387 * POSIX states that if bs is set and no other conversions 388 * than noerror, notrunc or sync are specified, the block 389 * is output without buffering as it is read. 390 */ 391 if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) == C_BS) { 392 out.dbcnt = in.dbcnt; 393 dd_out(1); 394 in.dbcnt = 0; 395 continue; 396 } 397 398 if (ddflags & C_SWAB) { 399 if ((n = in.dbrcnt) & 1) { 400 ++st.swab; 401 --n; 402 } 403 swab(in.dbp, in.dbp, (size_t)n); 404 } 405 406 in.dbp += in.dbrcnt; 407 (*cfunc)(); 408 if (need_summary) { 409 summary(); 410 } 411 } 412 } 413 414 /* 415 * Clean up any remaining I/O and flush output. If necessary, the output file 416 * is truncated. 417 */ 418 static void 419 dd_close(void) 420 { 421 if (cfunc == def) 422 def_close(); 423 else if (cfunc == block) 424 block_close(); 425 else if (cfunc == unblock) 426 unblock_close(); 427 if (ddflags & C_OSYNC && out.dbcnt && out.dbcnt < out.dbsz) { 428 if (ddflags & C_FILL) 429 memset(out.dbp, fill_char, out.dbsz - out.dbcnt); 430 else if (ddflags & (C_BLOCK | C_UNBLOCK)) 431 memset(out.dbp, ' ', out.dbsz - out.dbcnt); 432 else 433 memset(out.dbp, 0, out.dbsz - out.dbcnt); 434 out.dbcnt = out.dbsz; 435 } 436 if (out.dbcnt || pending) 437 dd_out(1); 438 439 /* 440 * If the file ends with a hole, ftruncate it to extend its size 441 * up to the end of the hole (without having to write any data). 442 */ 443 if (out.seek_offset > 0 && (out.flags & ISTRUNC)) { 444 if (ftruncate(out.fd, out.seek_offset) == -1) 445 err(1, "truncating %s", out.name); 446 } 447 } 448 449 void 450 dd_out(int force) 451 { 452 u_char *outp; 453 size_t cnt, i, n; 454 ssize_t nw; 455 static int warned; 456 int sparse; 457 458 /* 459 * Write one or more blocks out. The common case is writing a full 460 * output block in a single write; increment the full block stats. 461 * Otherwise, we're into partial block writes. If a partial write, 462 * and it's a character device, just warn. If a tape device, quit. 463 * 464 * The partial writes represent two cases. 1: Where the input block 465 * was less than expected so the output block was less than expected. 466 * 2: Where the input block was the right size but we were forced to 467 * write the block in multiple chunks. The original versions of dd(1) 468 * never wrote a block in more than a single write, so the latter case 469 * never happened. 470 * 471 * One special case is if we're forced to do the write -- in that case 472 * we play games with the buffer size, and it's usually a partial write. 473 */ 474 outp = out.db; 475 476 /* 477 * If force, first try to write all pending data, else try to write 478 * just one block. Subsequently always write data one full block at 479 * a time at most. 480 */ 481 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 482 cnt = n; 483 do { 484 sparse = 0; 485 if (ddflags & C_SPARSE) { 486 sparse = 1; /* Is buffer sparse? */ 487 for (i = 0; i < cnt; i++) 488 if (outp[i] != 0) { 489 sparse = 0; 490 break; 491 } 492 } 493 if (sparse && !force) { 494 pending += cnt; 495 nw = cnt; 496 } else { 497 if (pending != 0) { 498 /* 499 * Seek past hole. Note that we need to record the 500 * reached offset, because we might have no more data 501 * to write, in which case we'll need to call 502 * ftruncate to extend the file size. 503 */ 504 out.seek_offset = lseek(out.fd, pending, SEEK_CUR); 505 if (out.seek_offset == -1) 506 err(2, "%s: seek error creating sparse file", 507 out.name); 508 pending = 0; 509 } 510 if (cnt) { 511 nw = write(out.fd, outp, cnt); 512 out.seek_offset = 0; 513 } else { 514 return; 515 } 516 } 517 518 if (nw <= 0) { 519 if (nw == 0) 520 errx(1, "%s: end of device", out.name); 521 if (errno != EINTR) 522 err(1, "%s", out.name); 523 nw = 0; 524 } 525 526 outp += nw; 527 st.bytes += nw; 528 529 if ((size_t)nw == n && n == out.dbsz) 530 ++st.out_full; 531 else 532 ++st.out_part; 533 534 if ((size_t) nw != cnt) { 535 if (out.flags & ISTAPE) 536 errx(1, "%s: short write on tape device", 537 out.name); 538 if (out.flags & ISCHR && !warned) { 539 warned = 1; 540 warnx("%s: short write on character device", 541 out.name); 542 } 543 } 544 545 cnt -= nw; 546 } while (cnt != 0); 547 548 if ((out.dbcnt -= n) < out.dbsz) 549 break; 550 } 551 552 /* Reassemble the output block. */ 553 if (out.dbcnt) 554 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 555 out.dbp = out.db + out.dbcnt; 556 } 557