1 /* $NetBSD: dd.c,v 1.51 2016/09/05 01:00:07 sevan Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Keith Muller of the University of California, San Diego and Lance 9 * Visser of Convex Computer Corporation. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\ 39 The Regents of the University of California. All rights reserved."); 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94"; 45 #else 46 __RCSID("$NetBSD: dd.c,v 1.51 2016/09/05 01:00:07 sevan Exp $"); 47 #endif 48 #endif /* not lint */ 49 50 #include <sys/param.h> 51 #include <sys/stat.h> 52 #include <sys/ioctl.h> 53 #include <sys/mtio.h> 54 #include <sys/time.h> 55 56 #include <ctype.h> 57 #include <err.h> 58 #include <errno.h> 59 #include <fcntl.h> 60 #include <locale.h> 61 #include <signal.h> 62 #include <stdio.h> 63 #include <stdlib.h> 64 #include <string.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 redup_clean_fd(IO *); 74 static void setup(void); 75 76 IO in, out; /* input/output state */ 77 STAT st; /* statistics */ 78 void (*cfunc)(void); /* conversion function */ 79 uint64_t cpy_cnt; /* # of blocks to copy */ 80 static off_t pending = 0; /* pending seek if sparse */ 81 u_int ddflags; /* conversion options */ 82 #ifdef NO_IOFLAG 83 #define iflag O_RDONLY 84 #define oflag O_CREAT 85 #else 86 u_int iflag = O_RDONLY; /* open(2) flags for input file */ 87 u_int oflag = O_CREAT; /* open(2) flags for output file */ 88 #endif /* NO_IOFLAG */ 89 uint64_t cbsz; /* conversion block size */ 90 u_int files_cnt = 1; /* # of files to copy */ 91 uint64_t progress = 0; /* display sign of life */ 92 const u_char *ctab; /* conversion table */ 93 sigset_t infoset; /* a set blocking SIGINFO */ 94 const char *msgfmt = "posix"; /* default summary() message format */ 95 96 /* 97 * Ops for stdin/stdout and crunch'd dd. These are always host ops. 98 */ 99 static const struct ddfops ddfops_stdfd = { 100 .op_open = open, 101 .op_close = close, 102 .op_fcntl = fcntl, 103 .op_ioctl = ioctl, 104 .op_fstat = fstat, 105 .op_fsync = fsync, 106 .op_ftruncate = ftruncate, 107 .op_lseek = lseek, 108 .op_read = read, 109 .op_write = write, 110 }; 111 extern const struct ddfops ddfops_prog; 112 113 int 114 main(int argc, char *argv[]) 115 { 116 int ch; 117 118 setprogname(argv[0]); 119 (void)setlocale(LC_ALL, ""); 120 121 while ((ch = getopt(argc, argv, "")) != -1) { 122 switch (ch) { 123 default: 124 errx(EXIT_FAILURE, "usage: dd [operand ...]"); 125 /* NOTREACHED */ 126 } 127 } 128 argc -= (optind - 1); 129 argv += (optind - 1); 130 131 jcl(argv); 132 #ifndef CRUNCHOPS 133 if (ddfops_prog.op_init && ddfops_prog.op_init() == -1) 134 err(1, "prog init"); 135 #endif 136 setup(); 137 138 (void)signal(SIGINFO, summaryx); 139 (void)signal(SIGINT, terminate); 140 (void)sigemptyset(&infoset); 141 (void)sigaddset(&infoset, SIGINFO); 142 143 (void)atexit(summary); 144 145 while (files_cnt--) 146 dd_in(); 147 148 dd_close(); 149 exit(0); 150 /* NOTREACHED */ 151 } 152 153 static void 154 setup(void) 155 { 156 #ifdef CRUNCHOPS 157 const struct ddfops *prog_ops = &ddfops_stdfd; 158 #else 159 const struct ddfops *prog_ops = &ddfops_prog; 160 #endif 161 162 if (in.name == NULL) { 163 in.name = "stdin"; 164 in.fd = STDIN_FILENO; 165 in.ops = &ddfops_stdfd; 166 } else { 167 in.ops = prog_ops; 168 in.fd = ddop_open(in, in.name, iflag, 0); 169 if (in.fd < 0) 170 err(EXIT_FAILURE, "%s", in.name); 171 /* NOTREACHED */ 172 173 /* Ensure in.fd is outside the stdio descriptor range */ 174 redup_clean_fd(&in); 175 } 176 177 getfdtype(&in); 178 179 if (files_cnt > 1 && !(in.flags & ISTAPE)) { 180 errx(EXIT_FAILURE, "files is not supported for non-tape devices"); 181 /* NOTREACHED */ 182 } 183 184 if (out.name == NULL) { 185 /* No way to check for read access here. */ 186 out.fd = STDOUT_FILENO; 187 out.name = "stdout"; 188 out.ops = &ddfops_stdfd; 189 } else { 190 out.ops = prog_ops; 191 192 #ifndef NO_IOFLAG 193 if ((oflag & O_TRUNC) && (ddflags & C_SEEK)) { 194 errx(EXIT_FAILURE, "oflag=trunc is incompatible " 195 "with seek or oseek operands, giving up."); 196 /* NOTREACHED */ 197 } 198 if ((oflag & O_TRUNC) && (ddflags & C_NOTRUNC)) { 199 errx(EXIT_FAILURE, "oflag=trunc is incompatible " 200 "with conv=notrunc operand, giving up."); 201 /* NOTREACHED */ 202 } 203 #endif /* NO_IOFLAG */ 204 #define OFLAGS \ 205 (oflag | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 206 out.fd = ddop_open(out, out.name, O_RDWR | OFLAGS, DEFFILEMODE); 207 /* 208 * May not have read access, so try again with write only. 209 * Without read we may have a problem if output also does 210 * not support seeks. 211 */ 212 if (out.fd < 0) { 213 out.fd = ddop_open(out, out.name, O_WRONLY | OFLAGS, 214 DEFFILEMODE); 215 out.flags |= NOREAD; 216 } 217 if (out.fd < 0) { 218 err(EXIT_FAILURE, "%s", out.name); 219 /* NOTREACHED */ 220 } 221 222 /* Ensure out.fd is outside the stdio descriptor range */ 223 redup_clean_fd(&out); 224 } 225 226 getfdtype(&out); 227 228 /* 229 * Allocate space for the input and output buffers. If not doing 230 * record oriented I/O, only need a single buffer. 231 */ 232 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 233 size_t dbsz = out.dbsz; 234 if (!(ddflags & C_BS)) 235 dbsz += in.dbsz - 1; 236 if ((in.db = malloc(dbsz)) == NULL) { 237 err(EXIT_FAILURE, NULL); 238 /* NOTREACHED */ 239 } 240 out.db = in.db; 241 } else if ((in.db = 242 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 243 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) { 244 err(EXIT_FAILURE, NULL); 245 /* NOTREACHED */ 246 } 247 in.dbp = in.db; 248 out.dbp = out.db; 249 250 /* Position the input/output streams. */ 251 if (in.offset) 252 pos_in(); 253 if (out.offset) 254 pos_out(); 255 256 /* 257 * Truncate the output file; ignore errors because it fails on some 258 * kinds of output files, tapes, for example. 259 */ 260 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 261 (void)ddop_ftruncate(out, out.fd, (off_t)out.offset * out.dbsz); 262 263 /* 264 * If converting case at the same time as another conversion, build a 265 * table that does both at once. If just converting case, use the 266 * built-in tables. 267 */ 268 if (ddflags & (C_LCASE|C_UCASE)) { 269 #ifdef NO_CONV 270 /* Should not get here, but just in case... */ 271 errx(EXIT_FAILURE, "case conv and -DNO_CONV"); 272 /* NOTREACHED */ 273 #else /* NO_CONV */ 274 u_int cnt; 275 276 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 277 if (ddflags & C_LCASE) { 278 for (cnt = 0; cnt < 256; ++cnt) 279 casetab[cnt] = tolower(ctab[cnt]); 280 } else { 281 for (cnt = 0; cnt < 256; ++cnt) 282 casetab[cnt] = toupper(ctab[cnt]); 283 } 284 } else { 285 if (ddflags & C_LCASE) { 286 for (cnt = 0; cnt < 256; ++cnt) 287 casetab[cnt] = tolower(cnt); 288 } else { 289 for (cnt = 0; cnt < 256; ++cnt) 290 casetab[cnt] = toupper(cnt); 291 } 292 } 293 294 ctab = casetab; 295 #endif /* NO_CONV */ 296 } 297 298 (void)gettimeofday(&st.start, NULL); /* Statistics timestamp. */ 299 } 300 301 static void 302 getfdtype(IO *io) 303 { 304 struct mtget mt; 305 struct stat sb; 306 307 if (io->ops->op_fstat(io->fd, &sb)) { 308 err(EXIT_FAILURE, "%s", io->name); 309 /* NOTREACHED */ 310 } 311 if (S_ISCHR(sb.st_mode)) 312 io->flags |= io->ops->op_ioctl(io->fd, MTIOCGET, &mt) 313 ? ISCHR : ISTAPE; 314 else if (io->ops->op_lseek(io->fd, (off_t)0, SEEK_CUR) == -1 315 && errno == ESPIPE) 316 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 317 } 318 319 /* 320 * Move the parameter file descriptor to a descriptor that is outside the 321 * stdio descriptor range, if necessary. This is required to avoid 322 * accidentally outputting completion or error messages into the 323 * output file that were intended for the tty. 324 */ 325 static void 326 redup_clean_fd(IO *io) 327 { 328 int fd = io->fd; 329 int newfd; 330 331 if (fd != STDIN_FILENO && fd != STDOUT_FILENO && 332 fd != STDERR_FILENO) 333 /* File descriptor is ok, return immediately. */ 334 return; 335 336 /* 337 * 3 is the first descriptor greater than STD*_FILENO. Any 338 * free descriptor valued 3 or above is acceptable... 339 */ 340 newfd = io->ops->op_fcntl(fd, F_DUPFD, 3); 341 if (newfd < 0) { 342 err(EXIT_FAILURE, "dupfd IO"); 343 /* NOTREACHED */ 344 } 345 346 io->ops->op_close(fd); 347 io->fd = newfd; 348 } 349 350 static void 351 dd_in(void) 352 { 353 int flags; 354 int64_t n; 355 356 for (flags = ddflags;;) { 357 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 358 return; 359 360 /* 361 * Clear the buffer first if doing "sync" on input. 362 * If doing block operations use spaces. This will 363 * affect not only the C_NOERROR case, but also the 364 * last partial input block which should be padded 365 * with zero and not garbage. 366 */ 367 if (flags & C_SYNC) { 368 if (flags & (C_BLOCK|C_UNBLOCK)) 369 (void)memset(in.dbp, ' ', in.dbsz); 370 else 371 (void)memset(in.dbp, 0, in.dbsz); 372 } 373 374 n = ddop_read(in, in.fd, in.dbp, in.dbsz); 375 if (n == 0) { 376 in.dbrcnt = 0; 377 return; 378 } 379 380 /* Read error. */ 381 if (n < 0) { 382 383 /* 384 * If noerror not specified, die. POSIX requires that 385 * the warning message be followed by an I/O display. 386 */ 387 if (!(flags & C_NOERROR)) { 388 err(EXIT_FAILURE, "%s", in.name); 389 /* NOTREACHED */ 390 } 391 warn("%s", in.name); 392 summary(); 393 394 /* 395 * If it's not a tape drive or a pipe, seek past the 396 * error. If your OS doesn't do the right thing for 397 * raw disks this section should be modified to re-read 398 * in sector size chunks. 399 */ 400 if (!(in.flags & (ISPIPE|ISTAPE)) && 401 ddop_lseek(in, in.fd, (off_t)in.dbsz, SEEK_CUR)) 402 warn("%s", in.name); 403 404 /* If sync not specified, omit block and continue. */ 405 if (!(ddflags & C_SYNC)) 406 continue; 407 408 /* Read errors count as full blocks. */ 409 in.dbcnt += in.dbrcnt = in.dbsz; 410 ++st.in_full; 411 412 /* Handle full input blocks. */ 413 } else if ((uint64_t)n == in.dbsz) { 414 in.dbcnt += in.dbrcnt = n; 415 ++st.in_full; 416 417 /* Handle partial input blocks. */ 418 } else { 419 /* If sync, use the entire block. */ 420 if (ddflags & C_SYNC) 421 in.dbcnt += in.dbrcnt = in.dbsz; 422 else 423 in.dbcnt += in.dbrcnt = n; 424 ++st.in_part; 425 } 426 427 /* 428 * POSIX states that if bs is set and no other conversions 429 * than noerror, notrunc or sync are specified, the block 430 * is output without buffering as it is read. 431 */ 432 if (ddflags & C_BS) { 433 out.dbcnt = in.dbcnt; 434 dd_out(1); 435 in.dbcnt = 0; 436 continue; 437 } 438 439 if (ddflags & C_SWAB) { 440 if ((n = in.dbrcnt) & 1) { 441 ++st.swab; 442 --n; 443 } 444 swab(in.dbp, in.dbp, n); 445 } 446 447 in.dbp += in.dbrcnt; 448 (*cfunc)(); 449 } 450 } 451 452 /* 453 * Cleanup any remaining I/O and flush output. If necessary, output file 454 * is truncated. 455 */ 456 static void 457 dd_close(void) 458 { 459 460 if (cfunc == def) 461 def_close(); 462 else if (cfunc == block) 463 block_close(); 464 else if (cfunc == unblock) 465 unblock_close(); 466 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 467 (void)memset(out.dbp, 0, out.dbsz - out.dbcnt); 468 out.dbcnt = out.dbsz; 469 } 470 /* If there are pending sparse blocks, make sure 471 * to write out the final block un-sparse 472 */ 473 if ((out.dbcnt == 0) && pending) { 474 memset(out.db, 0, out.dbsz); 475 out.dbcnt = out.dbsz; 476 out.dbp = out.db + out.dbcnt; 477 pending -= out.dbsz; 478 } 479 if (out.dbcnt) 480 dd_out(1); 481 482 /* 483 * Reporting nfs write error may be deferred until next 484 * write(2) or close(2) system call. So, we need to do an 485 * extra check. If an output is stdout, the file structure 486 * may be shared with other processes and close(2) just 487 * decreases the reference count. 488 */ 489 if (out.fd == STDOUT_FILENO && ddop_fsync(out, out.fd) == -1 490 && errno != EINVAL) { 491 err(EXIT_FAILURE, "fsync stdout"); 492 /* NOTREACHED */ 493 } 494 if (ddop_close(out, out.fd) == -1) { 495 err(EXIT_FAILURE, "close"); 496 /* NOTREACHED */ 497 } 498 } 499 500 void 501 dd_out(int force) 502 { 503 static int warned; 504 int64_t cnt, n, nw; 505 u_char *outp; 506 507 /* 508 * Write one or more blocks out. The common case is writing a full 509 * output block in a single write; increment the full block stats. 510 * Otherwise, we're into partial block writes. If a partial write, 511 * and it's a character device, just warn. If a tape device, quit. 512 * 513 * The partial writes represent two cases. 1: Where the input block 514 * was less than expected so the output block was less than expected. 515 * 2: Where the input block was the right size but we were forced to 516 * write the block in multiple chunks. The original versions of dd(1) 517 * never wrote a block in more than a single write, so the latter case 518 * never happened. 519 * 520 * One special case is if we're forced to do the write -- in that case 521 * we play games with the buffer size, and it's usually a partial write. 522 */ 523 outp = out.db; 524 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 525 for (cnt = n;; cnt -= nw) { 526 527 if (!force && ddflags & C_SPARSE) { 528 int sparse, i; 529 sparse = 1; /* Is buffer sparse? */ 530 for (i = 0; i < cnt; i++) 531 if (outp[i] != 0) { 532 sparse = 0; 533 break; 534 } 535 if (sparse) { 536 pending += cnt; 537 outp += cnt; 538 nw = 0; 539 break; 540 } 541 } 542 if (pending != 0) { 543 if (ddop_lseek(out, 544 out.fd, pending, SEEK_CUR) == -1) 545 err(EXIT_FAILURE, "%s: seek error creating sparse file", 546 out.name); 547 } 548 nw = bwrite(&out, outp, cnt); 549 if (nw <= 0) { 550 if (nw == 0) 551 errx(EXIT_FAILURE, 552 "%s: end of device", out.name); 553 /* NOTREACHED */ 554 if (errno != EINTR) 555 err(EXIT_FAILURE, "%s", out.name); 556 /* NOTREACHED */ 557 nw = 0; 558 } 559 if (pending) { 560 st.bytes += pending; 561 st.sparse += pending/out.dbsz; 562 st.out_full += pending/out.dbsz; 563 pending = 0; 564 } 565 outp += nw; 566 st.bytes += nw; 567 if (nw == n) { 568 if ((uint64_t)n != out.dbsz) 569 ++st.out_part; 570 else 571 ++st.out_full; 572 break; 573 } 574 ++st.out_part; 575 if (nw == cnt) 576 break; 577 if (out.flags & ISCHR && !warned) { 578 warned = 1; 579 warnx("%s: short write on character device", out.name); 580 } 581 if (out.flags & ISTAPE) 582 errx(EXIT_FAILURE, 583 "%s: short write on tape device", out.name); 584 /* NOTREACHED */ 585 586 } 587 if ((out.dbcnt -= n) < out.dbsz) 588 break; 589 } 590 591 /* Reassemble the output block. */ 592 if (out.dbcnt) 593 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 594 out.dbp = out.db + out.dbcnt; 595 596 if (progress && (st.out_full + st.out_part) % progress == 0) 597 (void)write(STDERR_FILENO, ".", 1); 598 } 599 600 /* 601 * A protected against SIGINFO write 602 */ 603 ssize_t 604 bwrite(IO *io, const void *buf, size_t len) 605 { 606 sigset_t oset; 607 ssize_t rv; 608 int oerrno; 609 610 (void)sigprocmask(SIG_BLOCK, &infoset, &oset); 611 rv = io->ops->op_write(io->fd, buf, len); 612 oerrno = errno; 613 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 614 errno = oerrno; 615 return (rv); 616 } 617