1 /* $NetBSD: dd.c,v 1.50 2015/03/18 13:23:49 manu 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 1.50 2015/03/18 13:23:49 manu 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 int main(int, char *[]); 77 78 IO in, out; /* input/output state */ 79 STAT st; /* statistics */ 80 void (*cfunc)(void); /* conversion function */ 81 uint64_t cpy_cnt; /* # of blocks to copy */ 82 static off_t pending = 0; /* pending seek if sparse */ 83 u_int ddflags; /* conversion options */ 84 #ifdef NO_IOFLAG 85 #define iflag O_RDONLY 86 #define oflag O_CREAT 87 #else 88 u_int iflag = O_RDONLY; /* open(2) flags for input file */ 89 u_int oflag = O_CREAT; /* open(2) flags for output file */ 90 #endif /* NO_IOFLAG */ 91 uint64_t cbsz; /* conversion block size */ 92 u_int files_cnt = 1; /* # of files to copy */ 93 uint64_t progress = 0; /* display sign of life */ 94 const u_char *ctab; /* conversion table */ 95 sigset_t infoset; /* a set blocking SIGINFO */ 96 const char *msgfmt = "posix"; /* default summary() message format */ 97 98 /* 99 * Ops for stdin/stdout and crunch'd dd. These are always host ops. 100 */ 101 static const struct ddfops ddfops_stdfd = { 102 .op_open = open, 103 .op_close = close, 104 .op_fcntl = fcntl, 105 .op_ioctl = ioctl, 106 .op_fstat = fstat, 107 .op_fsync = fsync, 108 .op_ftruncate = ftruncate, 109 .op_lseek = lseek, 110 .op_read = read, 111 .op_write = write, 112 }; 113 extern const struct ddfops ddfops_prog; 114 115 int 116 main(int argc, char *argv[]) 117 { 118 int ch; 119 120 setprogname(argv[0]); 121 (void)setlocale(LC_ALL, ""); 122 123 while ((ch = getopt(argc, argv, "")) != -1) { 124 switch (ch) { 125 default: 126 errx(EXIT_FAILURE, "usage: dd [operand ...]"); 127 /* NOTREACHED */ 128 } 129 } 130 argc -= (optind - 1); 131 argv += (optind - 1); 132 133 jcl(argv); 134 #ifndef CRUNCHOPS 135 if (ddfops_prog.op_init && ddfops_prog.op_init() == -1) 136 err(1, "prog init"); 137 #endif 138 setup(); 139 140 (void)signal(SIGINFO, summaryx); 141 (void)signal(SIGINT, terminate); 142 (void)sigemptyset(&infoset); 143 (void)sigaddset(&infoset, SIGINFO); 144 145 (void)atexit(summary); 146 147 while (files_cnt--) 148 dd_in(); 149 150 dd_close(); 151 exit(0); 152 /* NOTREACHED */ 153 } 154 155 static void 156 setup(void) 157 { 158 #ifdef CRUNCHOPS 159 const struct ddfops *prog_ops = &ddfops_stdfd; 160 #else 161 const struct ddfops *prog_ops = &ddfops_prog; 162 #endif 163 164 if (in.name == NULL) { 165 in.name = "stdin"; 166 in.fd = STDIN_FILENO; 167 in.ops = &ddfops_stdfd; 168 } else { 169 in.ops = prog_ops; 170 in.fd = ddop_open(in, in.name, iflag, 0); 171 if (in.fd < 0) 172 err(EXIT_FAILURE, "%s", in.name); 173 /* NOTREACHED */ 174 175 /* Ensure in.fd is outside the stdio descriptor range */ 176 redup_clean_fd(&in); 177 } 178 179 getfdtype(&in); 180 181 if (files_cnt > 1 && !(in.flags & ISTAPE)) { 182 errx(EXIT_FAILURE, "files is not supported for non-tape devices"); 183 /* NOTREACHED */ 184 } 185 186 if (out.name == NULL) { 187 /* No way to check for read access here. */ 188 out.fd = STDOUT_FILENO; 189 out.name = "stdout"; 190 out.ops = &ddfops_stdfd; 191 } else { 192 out.ops = prog_ops; 193 194 #ifndef NO_IOFLAG 195 if ((oflag & O_TRUNC) && (ddflags & C_SEEK)) { 196 errx(EXIT_FAILURE, "oflag=trunc is incompatible " 197 "with seek or oseek operands, giving up."); 198 /* NOTREACHED */ 199 } 200 if ((oflag & O_TRUNC) && (ddflags & C_NOTRUNC)) { 201 errx(EXIT_FAILURE, "oflag=trunc is incompatible " 202 "with conv=notrunc operand, giving up."); 203 /* NOTREACHED */ 204 } 205 #endif /* NO_IOFLAG */ 206 #define OFLAGS \ 207 (oflag | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 208 out.fd = ddop_open(out, out.name, O_RDWR | OFLAGS, DEFFILEMODE); 209 /* 210 * May not have read access, so try again with write only. 211 * Without read we may have a problem if output also does 212 * not support seeks. 213 */ 214 if (out.fd < 0) { 215 out.fd = ddop_open(out, out.name, O_WRONLY | OFLAGS, 216 DEFFILEMODE); 217 out.flags |= NOREAD; 218 } 219 if (out.fd < 0) { 220 err(EXIT_FAILURE, "%s", out.name); 221 /* NOTREACHED */ 222 } 223 224 /* Ensure out.fd is outside the stdio descriptor range */ 225 redup_clean_fd(&out); 226 } 227 228 getfdtype(&out); 229 230 /* 231 * Allocate space for the input and output buffers. If not doing 232 * record oriented I/O, only need a single buffer. 233 */ 234 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 235 size_t dbsz = out.dbsz; 236 if (!(ddflags & C_BS)) 237 dbsz += in.dbsz - 1; 238 if ((in.db = malloc(dbsz)) == NULL) { 239 err(EXIT_FAILURE, NULL); 240 /* NOTREACHED */ 241 } 242 out.db = in.db; 243 } else if ((in.db = 244 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 245 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) { 246 err(EXIT_FAILURE, NULL); 247 /* NOTREACHED */ 248 } 249 in.dbp = in.db; 250 out.dbp = out.db; 251 252 /* Position the input/output streams. */ 253 if (in.offset) 254 pos_in(); 255 if (out.offset) 256 pos_out(); 257 258 /* 259 * Truncate the output file; ignore errors because it fails on some 260 * kinds of output files, tapes, for example. 261 */ 262 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 263 (void)ddop_ftruncate(out, out.fd, (off_t)out.offset * out.dbsz); 264 265 /* 266 * If converting case at the same time as another conversion, build a 267 * table that does both at once. If just converting case, use the 268 * built-in tables. 269 */ 270 if (ddflags & (C_LCASE|C_UCASE)) { 271 #ifdef NO_CONV 272 /* Should not get here, but just in case... */ 273 errx(EXIT_FAILURE, "case conv and -DNO_CONV"); 274 /* NOTREACHED */ 275 #else /* NO_CONV */ 276 u_int cnt; 277 278 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 279 if (ddflags & C_LCASE) { 280 for (cnt = 0; cnt < 256; ++cnt) 281 casetab[cnt] = tolower(ctab[cnt]); 282 } else { 283 for (cnt = 0; cnt < 256; ++cnt) 284 casetab[cnt] = toupper(ctab[cnt]); 285 } 286 } else { 287 if (ddflags & C_LCASE) { 288 for (cnt = 0; cnt < 256; ++cnt) 289 casetab[cnt] = tolower(cnt); 290 } else { 291 for (cnt = 0; cnt < 256; ++cnt) 292 casetab[cnt] = toupper(cnt); 293 } 294 } 295 296 ctab = casetab; 297 #endif /* NO_CONV */ 298 } 299 300 (void)gettimeofday(&st.start, NULL); /* Statistics timestamp. */ 301 } 302 303 static void 304 getfdtype(IO *io) 305 { 306 struct mtget mt; 307 struct stat sb; 308 309 if (io->ops->op_fstat(io->fd, &sb)) { 310 err(EXIT_FAILURE, "%s", io->name); 311 /* NOTREACHED */ 312 } 313 if (S_ISCHR(sb.st_mode)) 314 io->flags |= io->ops->op_ioctl(io->fd, MTIOCGET, &mt) 315 ? ISCHR : ISTAPE; 316 else if (io->ops->op_lseek(io->fd, (off_t)0, SEEK_CUR) == -1 317 && errno == ESPIPE) 318 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 319 } 320 321 /* 322 * Move the parameter file descriptor to a descriptor that is outside the 323 * stdio descriptor range, if necessary. This is required to avoid 324 * accidentally outputting completion or error messages into the 325 * output file that were intended for the tty. 326 */ 327 static void 328 redup_clean_fd(IO *io) 329 { 330 int fd = io->fd; 331 int newfd; 332 333 if (fd != STDIN_FILENO && fd != STDOUT_FILENO && 334 fd != STDERR_FILENO) 335 /* File descriptor is ok, return immediately. */ 336 return; 337 338 /* 339 * 3 is the first descriptor greater than STD*_FILENO. Any 340 * free descriptor valued 3 or above is acceptable... 341 */ 342 newfd = io->ops->op_fcntl(fd, F_DUPFD, 3); 343 if (newfd < 0) { 344 err(EXIT_FAILURE, "dupfd IO"); 345 /* NOTREACHED */ 346 } 347 348 io->ops->op_close(fd); 349 io->fd = newfd; 350 } 351 352 static void 353 dd_in(void) 354 { 355 int flags; 356 int64_t n; 357 358 for (flags = ddflags;;) { 359 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 360 return; 361 362 /* 363 * Clear the buffer first if doing "sync" on input. 364 * If doing block operations use spaces. This will 365 * affect not only the C_NOERROR case, but also the 366 * last partial input block which should be padded 367 * with zero and not garbage. 368 */ 369 if (flags & C_SYNC) { 370 if (flags & (C_BLOCK|C_UNBLOCK)) 371 (void)memset(in.dbp, ' ', in.dbsz); 372 else 373 (void)memset(in.dbp, 0, in.dbsz); 374 } 375 376 n = ddop_read(in, in.fd, in.dbp, in.dbsz); 377 if (n == 0) { 378 in.dbrcnt = 0; 379 return; 380 } 381 382 /* Read error. */ 383 if (n < 0) { 384 385 /* 386 * If noerror not specified, die. POSIX requires that 387 * the warning message be followed by an I/O display. 388 */ 389 if (!(flags & C_NOERROR)) { 390 err(EXIT_FAILURE, "%s", in.name); 391 /* NOTREACHED */ 392 } 393 warn("%s", in.name); 394 summary(); 395 396 /* 397 * If it's not a tape drive or a pipe, seek past the 398 * error. If your OS doesn't do the right thing for 399 * raw disks this section should be modified to re-read 400 * in sector size chunks. 401 */ 402 if (!(in.flags & (ISPIPE|ISTAPE)) && 403 ddop_lseek(in, in.fd, (off_t)in.dbsz, SEEK_CUR)) 404 warn("%s", in.name); 405 406 /* If sync not specified, omit block and continue. */ 407 if (!(ddflags & C_SYNC)) 408 continue; 409 410 /* Read errors count as full blocks. */ 411 in.dbcnt += in.dbrcnt = in.dbsz; 412 ++st.in_full; 413 414 /* Handle full input blocks. */ 415 } else if ((uint64_t)n == in.dbsz) { 416 in.dbcnt += in.dbrcnt = n; 417 ++st.in_full; 418 419 /* Handle partial input blocks. */ 420 } else { 421 /* If sync, use the entire block. */ 422 if (ddflags & C_SYNC) 423 in.dbcnt += in.dbrcnt = in.dbsz; 424 else 425 in.dbcnt += in.dbrcnt = n; 426 ++st.in_part; 427 } 428 429 /* 430 * POSIX states that if bs is set and no other conversions 431 * than noerror, notrunc or sync are specified, the block 432 * is output without buffering as it is read. 433 */ 434 if (ddflags & C_BS) { 435 out.dbcnt = in.dbcnt; 436 dd_out(1); 437 in.dbcnt = 0; 438 continue; 439 } 440 441 if (ddflags & C_SWAB) { 442 if ((n = in.dbrcnt) & 1) { 443 ++st.swab; 444 --n; 445 } 446 swab(in.dbp, in.dbp, n); 447 } 448 449 in.dbp += in.dbrcnt; 450 (*cfunc)(); 451 } 452 } 453 454 /* 455 * Cleanup any remaining I/O and flush output. If necessary, output file 456 * is truncated. 457 */ 458 static void 459 dd_close(void) 460 { 461 462 if (cfunc == def) 463 def_close(); 464 else if (cfunc == block) 465 block_close(); 466 else if (cfunc == unblock) 467 unblock_close(); 468 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 469 (void)memset(out.dbp, 0, out.dbsz - out.dbcnt); 470 out.dbcnt = out.dbsz; 471 } 472 /* If there are pending sparse blocks, make sure 473 * to write out the final block un-sparse 474 */ 475 if ((out.dbcnt == 0) && pending) { 476 memset(out.db, 0, out.dbsz); 477 out.dbcnt = out.dbsz; 478 out.dbp = out.db + out.dbcnt; 479 pending -= out.dbsz; 480 } 481 if (out.dbcnt) 482 dd_out(1); 483 484 /* 485 * Reporting nfs write error may be deferred until next 486 * write(2) or close(2) system call. So, we need to do an 487 * extra check. If an output is stdout, the file structure 488 * may be shared with other processes and close(2) just 489 * decreases the reference count. 490 */ 491 if (out.fd == STDOUT_FILENO && ddop_fsync(out, out.fd) == -1 492 && errno != EINVAL) { 493 err(EXIT_FAILURE, "fsync stdout"); 494 /* NOTREACHED */ 495 } 496 if (ddop_close(out, out.fd) == -1) { 497 err(EXIT_FAILURE, "close"); 498 /* NOTREACHED */ 499 } 500 } 501 502 void 503 dd_out(int force) 504 { 505 static int warned; 506 int64_t cnt, n, nw; 507 u_char *outp; 508 509 /* 510 * Write one or more blocks out. The common case is writing a full 511 * output block in a single write; increment the full block stats. 512 * Otherwise, we're into partial block writes. If a partial write, 513 * and it's a character device, just warn. If a tape device, quit. 514 * 515 * The partial writes represent two cases. 1: Where the input block 516 * was less than expected so the output block was less than expected. 517 * 2: Where the input block was the right size but we were forced to 518 * write the block in multiple chunks. The original versions of dd(1) 519 * never wrote a block in more than a single write, so the latter case 520 * never happened. 521 * 522 * One special case is if we're forced to do the write -- in that case 523 * we play games with the buffer size, and it's usually a partial write. 524 */ 525 outp = out.db; 526 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 527 for (cnt = n;; cnt -= nw) { 528 529 if (!force && ddflags & C_SPARSE) { 530 int sparse, i; 531 sparse = 1; /* Is buffer sparse? */ 532 for (i = 0; i < cnt; i++) 533 if (outp[i] != 0) { 534 sparse = 0; 535 break; 536 } 537 if (sparse) { 538 pending += cnt; 539 outp += cnt; 540 nw = 0; 541 break; 542 } 543 } 544 if (pending != 0) { 545 if (ddop_lseek(out, 546 out.fd, pending, SEEK_CUR) == -1) 547 err(EXIT_FAILURE, "%s: seek error creating sparse file", 548 out.name); 549 } 550 nw = bwrite(&out, outp, cnt); 551 if (nw <= 0) { 552 if (nw == 0) 553 errx(EXIT_FAILURE, 554 "%s: end of device", out.name); 555 /* NOTREACHED */ 556 if (errno != EINTR) 557 err(EXIT_FAILURE, "%s", out.name); 558 /* NOTREACHED */ 559 nw = 0; 560 } 561 if (pending) { 562 st.bytes += pending; 563 st.sparse += pending/out.dbsz; 564 st.out_full += pending/out.dbsz; 565 pending = 0; 566 } 567 outp += nw; 568 st.bytes += nw; 569 if (nw == n) { 570 if ((uint64_t)n != out.dbsz) 571 ++st.out_part; 572 else 573 ++st.out_full; 574 break; 575 } 576 ++st.out_part; 577 if (nw == cnt) 578 break; 579 if (out.flags & ISCHR && !warned) { 580 warned = 1; 581 warnx("%s: short write on character device", out.name); 582 } 583 if (out.flags & ISTAPE) 584 errx(EXIT_FAILURE, 585 "%s: short write on tape device", out.name); 586 /* NOTREACHED */ 587 588 } 589 if ((out.dbcnt -= n) < out.dbsz) 590 break; 591 } 592 593 /* Reassemble the output block. */ 594 if (out.dbcnt) 595 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 596 out.dbp = out.db + out.dbcnt; 597 598 if (progress && (st.out_full + st.out_part) % progress == 0) 599 (void)write(STDERR_FILENO, ".", 1); 600 } 601 602 /* 603 * A protected against SIGINFO write 604 */ 605 ssize_t 606 bwrite(IO *io, const void *buf, size_t len) 607 { 608 sigset_t oset; 609 ssize_t rv; 610 int oerrno; 611 612 (void)sigprocmask(SIG_BLOCK, &infoset, &oset); 613 rv = io->ops->op_write(io->fd, buf, len); 614 oerrno = errno; 615 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 616 errno = oerrno; 617 return (rv); 618 } 619