1 /* $NetBSD: dd.c,v 1.46 2010/12/23 21:55:40 riz 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 1.46 2010/12/23 21:55:40 riz 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 uint64_t cbsz; /* conversion block size */ 85 u_int files_cnt = 1; /* # of files to copy */ 86 uint64_t progress = 0; /* display sign of life */ 87 const u_char *ctab; /* conversion table */ 88 sigset_t infoset; /* a set blocking SIGINFO */ 89 90 static const struct ddfops ddfops_host = { 91 .op_open = open, 92 .op_close = close, 93 .op_fcntl = fcntl, 94 .op_ioctl = ioctl, 95 .op_fstat = fstat, 96 .op_fsync = fsync, 97 .op_ftruncate = ftruncate, 98 .op_lseek = lseek, 99 .op_read = read, 100 .op_write = write, 101 }; 102 103 int 104 main(int argc, char *argv[]) 105 { 106 int ch; 107 108 setprogname(argv[0]); 109 (void)setlocale(LC_ALL, ""); 110 111 while ((ch = getopt(argc, argv, "")) != -1) { 112 switch (ch) { 113 default: 114 errx(EXIT_FAILURE, "usage: dd [operand ...]"); 115 /* NOTREACHED */ 116 } 117 } 118 argc -= (optind - 1); 119 argv += (optind - 1); 120 121 jcl(argv); 122 setup(); 123 124 (void)signal(SIGINFO, summaryx); 125 (void)signal(SIGINT, terminate); 126 (void)sigemptyset(&infoset); 127 (void)sigaddset(&infoset, SIGINFO); 128 129 (void)atexit(summary); 130 131 while (files_cnt--) 132 dd_in(); 133 134 dd_close(); 135 exit(0); 136 /* NOTREACHED */ 137 } 138 139 static void 140 setup(void) 141 { 142 143 if (in.ops == NULL) 144 in.ops = &ddfops_host; 145 if (out.ops == NULL) 146 out.ops = &ddfops_host; 147 if (in.name == NULL) { 148 in.name = "stdin"; 149 in.fd = STDIN_FILENO; 150 } else { 151 in.fd = ddop_open(in, in.name, O_RDONLY, 0); 152 if (in.fd < 0) 153 err(EXIT_FAILURE, "%s", in.name); 154 /* NOTREACHED */ 155 156 /* Ensure in.fd is outside the stdio descriptor range */ 157 redup_clean_fd(&in); 158 } 159 160 getfdtype(&in); 161 162 if (files_cnt > 1 && !(in.flags & ISTAPE)) { 163 errx(EXIT_FAILURE, "files is not supported for non-tape devices"); 164 /* NOTREACHED */ 165 } 166 167 if (out.name == NULL) { 168 /* No way to check for read access here. */ 169 out.fd = STDOUT_FILENO; 170 out.name = "stdout"; 171 } else { 172 #define OFLAGS \ 173 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 174 out.fd = ddop_open(out, out.name, O_RDWR | OFLAGS, DEFFILEMODE); 175 /* 176 * May not have read access, so try again with write only. 177 * Without read we may have a problem if output also does 178 * not support seeks. 179 */ 180 if (out.fd < 0) { 181 out.fd = ddop_open(out, out.name, O_WRONLY | OFLAGS, 182 DEFFILEMODE); 183 out.flags |= NOREAD; 184 } 185 if (out.fd < 0) { 186 err(EXIT_FAILURE, "%s", out.name); 187 /* NOTREACHED */ 188 } 189 190 /* Ensure out.fd is outside the stdio descriptor range */ 191 redup_clean_fd(&out); 192 } 193 194 getfdtype(&out); 195 196 /* 197 * Allocate space for the input and output buffers. If not doing 198 * record oriented I/O, only need a single buffer. 199 */ 200 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 201 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) { 202 err(EXIT_FAILURE, NULL); 203 /* NOTREACHED */ 204 } 205 out.db = in.db; 206 } else if ((in.db = 207 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 208 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) { 209 err(EXIT_FAILURE, NULL); 210 /* NOTREACHED */ 211 } 212 in.dbp = in.db; 213 out.dbp = out.db; 214 215 /* Position the input/output streams. */ 216 if (in.offset) 217 pos_in(); 218 if (out.offset) 219 pos_out(); 220 221 /* 222 * Truncate the output file; ignore errors because it fails on some 223 * kinds of output files, tapes, for example. 224 */ 225 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 226 (void)ddop_ftruncate(out, out.fd, (off_t)out.offset * out.dbsz); 227 228 /* 229 * If converting case at the same time as another conversion, build a 230 * table that does both at once. If just converting case, use the 231 * built-in tables. 232 */ 233 if (ddflags & (C_LCASE|C_UCASE)) { 234 #ifdef NO_CONV 235 /* Should not get here, but just in case... */ 236 errx(EXIT_FAILURE, "case conv and -DNO_CONV"); 237 /* NOTREACHED */ 238 #else /* NO_CONV */ 239 u_int cnt; 240 241 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 242 if (ddflags & C_LCASE) { 243 for (cnt = 0; cnt < 256; ++cnt) 244 casetab[cnt] = tolower(ctab[cnt]); 245 } else { 246 for (cnt = 0; cnt < 256; ++cnt) 247 casetab[cnt] = toupper(ctab[cnt]); 248 } 249 } else { 250 if (ddflags & C_LCASE) { 251 for (cnt = 0; cnt < 256; ++cnt) 252 casetab[cnt] = tolower(cnt); 253 } else { 254 for (cnt = 0; cnt < 256; ++cnt) 255 casetab[cnt] = toupper(cnt); 256 } 257 } 258 259 ctab = casetab; 260 #endif /* NO_CONV */ 261 } 262 263 (void)gettimeofday(&st.start, NULL); /* Statistics timestamp. */ 264 } 265 266 static void 267 getfdtype(IO *io) 268 { 269 struct mtget mt; 270 struct stat sb; 271 272 if (io->ops->op_fstat(io->fd, &sb)) { 273 err(EXIT_FAILURE, "%s", io->name); 274 /* NOTREACHED */ 275 } 276 if (S_ISCHR(sb.st_mode)) 277 io->flags |= io->ops->op_ioctl(io->fd, MTIOCGET, &mt) 278 ? ISCHR : ISTAPE; 279 else if (io->ops->op_lseek(io->fd, (off_t)0, SEEK_CUR) == -1 280 && errno == ESPIPE) 281 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 282 } 283 284 /* 285 * Move the parameter file descriptor to a descriptor that is outside the 286 * stdio descriptor range, if necessary. This is required to avoid 287 * accidentally outputting completion or error messages into the 288 * output file that were intended for the tty. 289 */ 290 static void 291 redup_clean_fd(IO *io) 292 { 293 int fd = io->fd; 294 int newfd; 295 296 if (fd != STDIN_FILENO && fd != STDOUT_FILENO && 297 fd != STDERR_FILENO) 298 /* File descriptor is ok, return immediately. */ 299 return; 300 301 /* 302 * 3 is the first descriptor greater than STD*_FILENO. Any 303 * free descriptor valued 3 or above is acceptable... 304 */ 305 newfd = io->ops->op_fcntl(fd, F_DUPFD, 3); 306 if (newfd < 0) { 307 err(EXIT_FAILURE, "dupfd IO"); 308 /* NOTREACHED */ 309 } 310 311 io->ops->op_close(fd); 312 io->fd = newfd; 313 } 314 315 static void 316 dd_in(void) 317 { 318 int flags; 319 int64_t n; 320 321 for (flags = ddflags;;) { 322 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 323 return; 324 325 /* 326 * Clear the buffer first if doing "sync" on input. 327 * If doing block operations use spaces. This will 328 * affect not only the C_NOERROR case, but also the 329 * last partial input block which should be padded 330 * with zero and not garbage. 331 */ 332 if (flags & C_SYNC) { 333 if (flags & (C_BLOCK|C_UNBLOCK)) 334 (void)memset(in.dbp, ' ', in.dbsz); 335 else 336 (void)memset(in.dbp, 0, in.dbsz); 337 } 338 339 n = ddop_read(in, in.fd, in.dbp, in.dbsz); 340 if (n == 0) { 341 in.dbrcnt = 0; 342 return; 343 } 344 345 /* Read error. */ 346 if (n < 0) { 347 348 /* 349 * If noerror not specified, die. POSIX requires that 350 * the warning message be followed by an I/O display. 351 */ 352 if (!(flags & C_NOERROR)) { 353 err(EXIT_FAILURE, "%s", in.name); 354 /* NOTREACHED */ 355 } 356 warn("%s", in.name); 357 summary(); 358 359 /* 360 * If it's not a tape drive or a pipe, seek past the 361 * error. If your OS doesn't do the right thing for 362 * raw disks this section should be modified to re-read 363 * in sector size chunks. 364 */ 365 if (!(in.flags & (ISPIPE|ISTAPE)) && 366 ddop_lseek(in, in.fd, (off_t)in.dbsz, SEEK_CUR)) 367 warn("%s", in.name); 368 369 /* If sync not specified, omit block and continue. */ 370 if (!(ddflags & C_SYNC)) 371 continue; 372 373 /* Read errors count as full blocks. */ 374 in.dbcnt += in.dbrcnt = in.dbsz; 375 ++st.in_full; 376 377 /* Handle full input blocks. */ 378 } else if ((uint64_t)n == in.dbsz) { 379 in.dbcnt += in.dbrcnt = n; 380 ++st.in_full; 381 382 /* Handle partial input blocks. */ 383 } else { 384 /* If sync, use the entire block. */ 385 if (ddflags & C_SYNC) 386 in.dbcnt += in.dbrcnt = in.dbsz; 387 else 388 in.dbcnt += in.dbrcnt = n; 389 ++st.in_part; 390 } 391 392 /* 393 * POSIX states that if bs is set and no other conversions 394 * than noerror, notrunc or sync are specified, the block 395 * is output without buffering as it is read. 396 */ 397 if (ddflags & C_BS) { 398 out.dbcnt = in.dbcnt; 399 dd_out(1); 400 in.dbcnt = 0; 401 continue; 402 } 403 404 if (ddflags & C_SWAB) { 405 if ((n = in.dbrcnt) & 1) { 406 ++st.swab; 407 --n; 408 } 409 swab(in.dbp, in.dbp, n); 410 } 411 412 in.dbp += in.dbrcnt; 413 (*cfunc)(); 414 } 415 } 416 417 /* 418 * Cleanup any remaining I/O and flush output. If necessary, output file 419 * is truncated. 420 */ 421 static void 422 dd_close(void) 423 { 424 425 if (cfunc == def) 426 def_close(); 427 else if (cfunc == block) 428 block_close(); 429 else if (cfunc == unblock) 430 unblock_close(); 431 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 432 (void)memset(out.dbp, 0, out.dbsz - out.dbcnt); 433 out.dbcnt = out.dbsz; 434 } 435 /* If there are pending sparse blocks, make sure 436 * to write out the final block un-sparse 437 */ 438 if ((out.dbcnt == 0) && pending) { 439 memset(out.db, 0, out.dbsz); 440 out.dbcnt = out.dbsz; 441 out.dbp = out.db + out.dbcnt; 442 pending -= out.dbsz; 443 } 444 if (out.dbcnt) 445 dd_out(1); 446 447 /* 448 * Reporting nfs write error may be deferred until next 449 * write(2) or close(2) system call. So, we need to do an 450 * extra check. If an output is stdout, the file structure 451 * may be shared with other processes and close(2) just 452 * decreases the reference count. 453 */ 454 if (out.fd == STDOUT_FILENO && ddop_fsync(out, out.fd) == -1 455 && errno != EINVAL) { 456 err(EXIT_FAILURE, "fsync stdout"); 457 /* NOTREACHED */ 458 } 459 if (ddop_close(out, out.fd) == -1) { 460 err(EXIT_FAILURE, "close"); 461 /* NOTREACHED */ 462 } 463 } 464 465 void 466 dd_out(int force) 467 { 468 static int warned; 469 int64_t cnt, n, nw; 470 u_char *outp; 471 472 /* 473 * Write one or more blocks out. The common case is writing a full 474 * output block in a single write; increment the full block stats. 475 * Otherwise, we're into partial block writes. If a partial write, 476 * and it's a character device, just warn. If a tape device, quit. 477 * 478 * The partial writes represent two cases. 1: Where the input block 479 * was less than expected so the output block was less than expected. 480 * 2: Where the input block was the right size but we were forced to 481 * write the block in multiple chunks. The original versions of dd(1) 482 * never wrote a block in more than a single write, so the latter case 483 * never happened. 484 * 485 * One special case is if we're forced to do the write -- in that case 486 * we play games with the buffer size, and it's usually a partial write. 487 */ 488 outp = out.db; 489 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 490 for (cnt = n;; cnt -= nw) { 491 492 if (!force && ddflags & C_SPARSE) { 493 int sparse, i; 494 sparse = 1; /* Is buffer sparse? */ 495 for (i = 0; i < cnt; i++) 496 if (outp[i] != 0) { 497 sparse = 0; 498 break; 499 } 500 if (sparse) { 501 pending += cnt; 502 outp += cnt; 503 nw = 0; 504 break; 505 } 506 } 507 if (pending != 0) { 508 if (ddop_lseek(out, 509 out.fd, pending, SEEK_CUR) == -1) 510 err(EXIT_FAILURE, "%s: seek error creating sparse file", 511 out.name); 512 } 513 nw = bwrite(&out, outp, cnt); 514 if (nw <= 0) { 515 if (nw == 0) 516 errx(EXIT_FAILURE, 517 "%s: end of device", out.name); 518 /* NOTREACHED */ 519 if (errno != EINTR) 520 err(EXIT_FAILURE, "%s", out.name); 521 /* NOTREACHED */ 522 nw = 0; 523 } 524 if (pending) { 525 st.bytes += pending; 526 st.sparse += pending/out.dbsz; 527 st.out_full += pending/out.dbsz; 528 pending = 0; 529 } 530 outp += nw; 531 st.bytes += nw; 532 if (nw == n) { 533 if ((uint64_t)n != out.dbsz) 534 ++st.out_part; 535 else 536 ++st.out_full; 537 break; 538 } 539 ++st.out_part; 540 if (nw == cnt) 541 break; 542 if (out.flags & ISCHR && !warned) { 543 warned = 1; 544 warnx("%s: short write on character device", out.name); 545 } 546 if (out.flags & ISTAPE) 547 errx(EXIT_FAILURE, 548 "%s: short write on tape device", out.name); 549 /* NOTREACHED */ 550 551 } 552 if ((out.dbcnt -= n) < out.dbsz) 553 break; 554 } 555 556 /* Reassemble the output block. */ 557 if (out.dbcnt) 558 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 559 out.dbp = out.db + out.dbcnt; 560 561 if (progress && (st.out_full + st.out_part) % progress == 0) 562 (void)write(STDERR_FILENO, ".", 1); 563 } 564 565 /* 566 * A protected against SIGINFO write 567 */ 568 ssize_t 569 bwrite(IO *io, const void *buf, size_t len) 570 { 571 sigset_t oset; 572 ssize_t rv; 573 int oerrno; 574 575 (void)sigprocmask(SIG_BLOCK, &infoset, &oset); 576 rv = io->ops->op_write(io->fd, buf, len); 577 oerrno = errno; 578 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 579 errno = oerrno; 580 return (rv); 581 } 582